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Welcome to my DEF CON Ham Radio Village talk on my rover van.

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My name is Pete Koback and my call sign is Kilo Zero.

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Bravo Alpha Kilo.

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I want to say first that I'm really happy to be here at DEF CON, even virtually, because I spent 17 years in web application security, and although I attended quite a few security conferences in that time, I never did get to DEF CON, so I'm glad I'm here now,

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and I'm glad you're here with me.

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I first got licensed relatively recently, after waiting 40 years when I first had an interest in ham radio as a teenager, but didn't have money, and then didn't have time with a family and career.

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And I had been fascinated by reading about the activity of roving, either activating counties and state QSO parties, or grids and VHF contests.

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And my first effort was in 2014 in the Pennsylvania QSO party, my home state, and I won the category, mostly because there wasn't much competition in the category, but still, I had a lot of fun doing it, and it wasn't bad to win either.

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So, a kind of a career was started there in roving and contests.

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When I first started, I used the family minivan, and on the left here you can see four low VHF bands on a rotator in the back of the van.

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And here is the HF antenna I started with, which was an elevated ground plane.

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I since replaced that with a screwdriver antenna, because although this antenna works well, it takes too long to set up.

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Although I had fun operating the family minivan, it was a pain in the neck to have to tear it down each time after I'm done, and then build it out the next time.

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Also, I couldn't drill holes, so I was thinking, gee, it sure would be nice to have a dedicated vehicle.

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The ultimate such vehicle would be electronic news gathering.

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It would have a pneumatic mask, power, and racks, and it would be a perfect base for a VHF ham rover.

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I looked every so often, not really very seriously.

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They always seemed to be offered far away, and I wasn't really looking in any kind of systematic way.

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However, in the summer of 2016, my buddy Rob found the TV van that was only two hours away.

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So we went up there.

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Since he's a gearhead, he gave it a mechanical thumbs up.

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We saw that the generated pneumatic mask worked, and after going away for a couple weeks and thinking about it, I purchased it and paid for it, in effect, by delaying my retirement.

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Here's a list of the features in the van.

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I won't go through these step-by-step, but a pneumatic mask, power generators, a powerful engine because it's quite a heavy vehicle, and a flat roof with a ladder.

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That was meant for TV reporting.

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That would make it easier to climb up there and install antennas that I needed.

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Here's what the van looked like when it was on offer at the dealer.

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You can see some pretty heavy antennas on the roof of the van that would have to be removed for my own antennas to be installed.

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And here's a look at the interior production area, where you can see that they removed all their expensive equipment and left the cables behind.

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I bought the van at the end of October of 2016, registered it, replaced the batteries, and something I didn't even think about was garaging it.

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So I didn't have a garage tall enough for it, so I threw a tarp over it, which didn't work all that well, then certainly didn't look very good, and didn't have any build progress that winter.

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In the spring, I took down the antennas I could by disassembling it and walking the antennas down the ladder, but the front antenna for satellite was too heavy, and another buddy of mine from a VHF club, Phil K3TOF, helped me by taking it off with a pulley at his pole barn.

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Ironically, the first radio that I had installed in the van was not a ham radio, but was a combination radio, backup camera, and navigation device.

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Also, I had a Bluetooth player for long drives, which is not a small thing when you're doing a long drive by yourself.

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One of my first bad surprises was in the spring after I bought it, I found that the generator, the motor part started right up, which is good, but there was no voltage I could find.

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I was surprised by this, because we saw the meters on at the dealer, and it ran the pneumatic mass, at least I thought so.

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I finally discovered that the AC we saw at the dealer had come from the van engine, and I'm kind of embarrassed to admit that I didn't even know it had that feature.

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I guess it's good to have the feature, but bad that I didn't know about it.

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So, the generator part of that gasoline gen set had to be rebuilt expensively, and it took quite a while.

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At the same time, 2017 is my first year of retirement, and I did a lot of operating because I had the freedom to do so, and because I was operating, I didn't make much progress on the van.

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Finally, at near the end of the year, I deconstructed the minivan Rover in the hopes that I would have more time, or force myself at least to have more time, to outfit the TV van.

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The next winter, I found a garage for it that was relatively new, and the problem was it was one hour drive each way, but at least I had a place to keep it over the winter, and could do some work inside during the winter months.

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The first big project in the winter was to remove the cables that were left behind.

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I did so by not cutting them, but removing them and putting them aside, or wrapping them up here on the side and cleaning the whole van, which had not seen much cleaning since it was built in 2001.

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The first thing I ever built for the van was a shore power connection.

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Here's a little cable with an adapter that was kind of unusual.

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You would have thought it would be standard in the RV world.

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It was not, so it was hard to find and surprisingly expensive, but at least my first build was successful.

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The first of many things I built for the van down the years.

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Now in 2018, unfortunately, most progress halted because of a major series of basement floods we had at home.

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It took out my home station and forced me to spend a lot of time fixing it up or preparing it to be fixed up and renewed again.

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So very little progress was made on the TV van because of that.

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2019, though, had quite a bit of progress in the van.

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I won't go through this entire list, but one of the big features of that year was operating in the Canadian National Parks on the Air program, installing radios, the power systems I used during that operation, and a microwave power shelf.

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So in contrast to the previous year, I did make a lot of progress two years ago.

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In this calendar year, though, the major theme, including the very end of last year, was mechanical problems with the engine, in particular the serpentine belt in the engine.

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So the van was out of commission for many weeks in two different events, not allowing me to make progress in building or operating the van.

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In between the events, I did go on what I called Corona Roads to local parks and operated from parks, since I could still be isolated from other people while operating inside the van.

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And right at the moment, the station is down for upgrades, but that's a good thing, and it'll be back on the air shortly.

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Now I'd like to talk about power, which was most of my effort of building the interior of the van so far.

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So I started with surveying the capabilities of the van as is.

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The van has three 5 kilowatt AC sources, a generator set that I talked about, an origin that was power from the vehicle, and the plug-in shore power.

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So the problem with the generator set was that it was very loud inside.

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Audio-wise, it was really loud and shaky, and not only was it loud inside the van, if I was anywhere where the public would be, like a park, it would be really distracting and not a nice thing to subject other people to.

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The origin is relatively quiet because just the van engine is running, but RF-wise, it was horribly, horribly noisy, so that was out.

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Lastly, there's RF noise just from the van engine even when the origin system wasn't on, so my overall conclusion was that I needed batteries for doing weak signal radio.

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I couldn't rely on any of the internal generating sources.

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The DC power system included two batteries wired in parallel permanently, which was a shame because it would have been nice if the auxiliary battery was switched in.

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I noticed there was no protection for high current circuits, which made some additions to the DC power system dangerous.

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I did have available 320 amp radio DC circuits, but that's really not enough power to even have barefoot power, no less amplifiers.

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The battery charger that they left behind that I started trying to use was actually burned out, which is probably why they left it behind.

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So my overall conclusion was that I also needed a separate radio station DC power system.

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I couldn't take much advantage of anything that was existing in the van for DC power.

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So what were my power assumptions when I started?

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I was going to use my home station Flex 5000 SDR.

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The thing about that series of Flex radios was that the radio processing was done on a PC via firewire.

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The laptop was out of the question because of using less reliable connections.

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So I needed to use a rock-mounted desktop class PC, and that meant I needed AC power for that PC.

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So going through this line of assumptions led me to the conclusion that the station would be based on AC power and DC would come from conventional power supplies just like you'd use at home.

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And I'd use batteries and an inverter for AC power because, as I said before, I couldn't rely on the internal generators.

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I decided that the AC power would be up to 3 kilowatts so I could eventually accommodate the limit amplifiers.

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And I wanted to make that decision once because it was heavy and hard to wire.

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So I wanted to make sure I was future-proof even if I wasn't going out with the limit amplifiers at first.

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I would use direct battery power for the station DC and I would use dual batteries for flexibility.

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I could use the AC inverter from one battery with the DC supply from another or maybe I could use one while charging the other.

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I knew I would get good flexibility by having two batteries.

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And lastly, I would need a charger maintainer for the van batteries because the van would be in storage a lot of the time and, like any vehicle, you need to maintain those lead-acid batteries.

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Here's a diagram of the overall power design context.

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I first have to apologize because my writing is so terrible.

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It seems like I learned to print and to draw and then just stopped learning when I was at the age of 7.

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So my drawings are awful and I don't have the time or patience to draw them in a drawing program.

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I hope you'll forgive me for these awful looking diagrams.

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The overall context diagram includes the old systems and the new systems.

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It includes both AC and DC.

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And we're going to be going over many of these systems one at a time.

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We went over the requirements, the context diagram, and now we'll spend some time on the implementation of those power systems.

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Here's a picture of the key power components.

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Here's that 3 kW inverter, charger, switch that I mentioned.

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And here are two 200 Ah each.

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Nominally 12 volt batteries.

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These are 115 pounds each, so they are quite beefy.

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Batteries actually deliver an enormous amount of current.

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Even just mounting the batteries required skills I didn't have before.

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And that's one theme I wanted to bring out.

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This entire project taught me quite a few really basic mechanical real world skills I didn't have before.

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Many people learn how to do things like a cut with a table saw when they're in their teenage years.

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I didn't know any of that.

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I had a virtual life on computers almost my entire career.

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This was new to me.

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And it was scary making my first cut on my first table saw.

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So this is just one especially dangerous example of things that I learned to do just for the sake of the van.

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So using that table saw and my newfound skills, I cut boards to constrain those 115 pound batteries horizontally.

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I used straps that you can just barely see here and here to constrain the batteries vertically.

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And here is a binding post to tie together all the negative side of the system.

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So let me describe the A.C.

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part of the system build.

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Over here is the native A.C.

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system that was already in the van and here is my new A.C.

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system.

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The inverter charger switch can supply

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current to the A.C.

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system in a back feed arrangement and the power is supplied from the shore power into the new A.C.

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system, into that big blue box I showed.

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I would have 15 amp outlets that are existing in the racks and I would also build 25 amp outlets that were brand new.

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And to run off of battery power there would also be a very large 200 amp capacity connection to the battery system.

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So here is a diagram of the A.C.

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power circuit.

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What I did was to connect into, rather than replace, I connected into existing A.C.

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circuits in the van.

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So here is a supply that I pulled off of these original circuits that are no longer used in the van to supply A.C.

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power into the inverter, say from shore power when I'm, for instance, charging the batteries.

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And then the output of the inverter would go through a new 30 amp circuit breaker and then branch off into two of the racks for an existing 15 amp circuit and another existing 15 amp circuit for the other two racks.

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And lastly, I installed two new sockets for higher current A.C.

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supply.

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And here is what the new A.C.

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power panel looked like.

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This is the main circuit breaker.

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Here are the two 15 amp circuit breakers in a double arrangement.

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And here are two higher current sockets for someday for legal limit amplifiers that require this amount of A.C.

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current.

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Here are the two multi-wired cables going back to the electrical panel.

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We'll take a look at the electrical panel shortly.

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And here's that same system mounted onto the back of rack number one.

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Now these two multi-wired cables go to the A.C.

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distribution in the back driver's side of the van.

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Which looks like this.

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This is a before picture and this is an after picture.

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And you can see those same two multi-wired cables coming up into the panel on this side and being wired into existing circuits.

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And you can see that I was lucky that this terminal block had a lot of unused circuits.

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So that made it a lot easier than it would otherwise have been to wire in my own connections into the A.C.

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panel.

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Now I added some labels to the native power panel to tell me how the switches should be laid out, at least in ordinary operating conditions.

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So this is the input power into that big blue box, the inverter charger switch.

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And these, even though they're off in this picture, these would normally always be on.

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And in contrast, I am connecting the output of that inverter to these two circuits.

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So normally these would be off because I already have current on them.

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But this does allow me to do a back feed into the rest of the A.C.

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system if I had some emergency that would require me to supply A.C.

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to other parts of the van besides the rack circuits that were intended.

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Now here's both D.C.

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power panels, and we'll be going into this in detail.

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This is a picture at the bottom of rack number two, in other words, the middle of the three racks.

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So I'm first going to be talking about the battery system that's really at the core of the entire system that supplies power to both the A.C.

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system that we just talked about and to the station power.

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The battery circuit is relatively simple electrically, but it was hard to build because of the size of the cables that I had to deal with.

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So you can see that here are the two batteries I showed in the picture earlier.

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Each battery has two fuses mounted right on the terminal, which I didn't even know existed before I started this project.

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So that's a nice safety feature to have a fuse right on the terminal of the battery.

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200 amp coming off of each battery for the inverter charger to give it enough power to supply three kilowatts of A.C.

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power.

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And then the 80 amp circuit coming off of each battery goes to this switch and then to the station power system here.

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Here's more of a close -up of the battery switch panel.

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So here are the two switches that I showed in that circuit diagram.

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They can select either battery or both together or both off.

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These two green panel meters alternately show voltage and current, but only when their respective switch is on.

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And this always shows voltage to the batteries no matter the switch position.

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All these meters are only on when the meter switch is on.

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And that allows me to not drain the battery unnecessarily when, say, the van is in storage.

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Here's the back of that same panel.

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You can see how large some of these cables are.

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This is a quad-zero gauge wire.

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It's very big and very expensive and really hard to work with, as you might imagine.

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These are two double-zero cables that go to each battery.

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And this is the 200 amp side of the circuit.

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And, of course, this is the 80 amp side of the circuit with 4-gauge wire being used for that wiring.

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Here's a top view of the installed batteries with the two fuses that I mentioned earlier here connecting to the panel.

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And you can just barely see down here the common connection point for all the negative leads.

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In between the two batteries is a, which I'll be talking about shortly, an 80 amp boost regulator.

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It just happened to fit very well between the batteries just by chance.

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So it's a nice spot for it.

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It's nice and cozy in there without having to take up, say, a rack space.

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So that was a lucky thing.

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Now let's talk about the two-way charging system.

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And here are the controls for that two-way charging system.

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On the right is another instance of that volt-amp meter.

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In this case, this is showing the voltage and current from or to the van battery system.

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This is a meter switch, like I talked before, so I can turn this meter off when the van is in storage.

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And here's a double-throw switch that allows me to put current in either direction into the batteries from or to the native vehicle battery.

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So in the up position, I can charge the station from the van alternator while the van is in operation.

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In the down position, I can charge the van batteries when the van is stationary.

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I can charge the van batteries while AC power is supplied.

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Here's a circuit of that two-way charging system.

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So the key part of the system is these two 65-amp solenoids that connect the station battery to the vehicle battery when necessary.

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These are in turn energized by this smaller capacity relay that fires six seconds after the ignition signal is set.

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I have this six-second delay in order to allow the van engine to stabilize before I connect the large station batteries to the van batteries.

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And down here is something called a battery tender, or in other words, a battery maintainer charger.

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And this can be switched in or out by that double-throw toggle switch that I showed in the panel before.

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And this supplies current into the van DC system with the solenoids off in that position so I can charge into the van DC system.

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Next I'm going to talk about the station power system.

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And that is fed from the battery system with up to 80 amps and then moves as a regulated 80 amps into station equipment or into the computer.

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And here's the station power control panel on the left-hand side of that same rack panel I showed before.

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One controls the input into the 80 amp booster, and the other controls whether I am supplying power to HF components, VHF components, or both.

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The station battery switch output, that 80 amp switch I showed in the lower panel, first goes to a MIDI fuse block to supply current to the unregulated battery output binding post.

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It supplies current in from the two-way charging system I showed earlier.

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And the main circuit is an 80 amp fuse that protects the rest of the system for all the other station components.

216
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There's a panel switch that I showed in the previous picture that can turn this circuit on or off and also can have a supply instead of from the station batteries from some power supply if I ever wanted to run the station on AC instead of DC.

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That goes into that 80 amp boost regulator that was between the two batteries that I showed earlier.

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I have a shunt resistor and an analog meter to measure the instantaneous current being used by the entire system.

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And the output of the boost regulator goes to binding posts for further distribution.

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And here is that further distribution.

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This is the connection point from the left-hand side of the previous diagram.

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One side goes to an unswitched power pole distribution for things like radios that I'm going to use for both HF and VHF.

223
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The rest of the distribution goes through a panel switch to select either the HF or VHF equipment.

224
00:28:56,780 --> 00:29:13,180
And the HF cable goes into a MIDI fuse box on another rack shelf into the amplifier and a power pole distribution for HF-only components like the screwdriver antenna and the remote SWR meter.

225
00:29:13,280 --> 00:29:18,560
In the VHF position, we have a high current and a low current connection.

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The high current goes through a MIDI fuse box that I used in my old minivan Rover to go to for medium power amplifiers for the low VHF bands.

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And another branch goes to a power pole distribution system for low current components like a small flex radio amplifier fans, transverters, and an SWR power meter power system.

228
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One little branch circuit from the previous diagram goes through a fuse box that can distribute unregulated battery power.

229
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And the only component using that so far is the computer.

230
00:30:03,560 --> 00:30:05,720
And we'll talk about that a little bit later.

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00:30:11,330 --> 00:30:16,630
Here's a picture of the station power distribution shelf.

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So this is the connector I showed before that was scary to put on because it was a live hot DC that would have welded my tools if I wasn't careful.

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The two fuses for the input DC from the van.

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00:30:31,730 --> 00:30:42,390
Here's the solenoid relays and the relay timer for the delay of connecting the station batteries to the van alternator.

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Here's a first fuse box for the distribution of battery power to three different destinations, the most important of which is the booster.

236
00:30:57,570 --> 00:31:08,170
And that cable goes here to the front panel switch that selects either the battery or a power supply for the input to the booster.

237
00:31:08,170 --> 00:31:15,830
The booster is underneath this panel and comes out here on the hot side and on the ground side.

238
00:31:15,830 --> 00:31:19,050
So this is where the regulated voltage comes out from the booster.

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00:31:19,050 --> 00:31:35,910
That can be connected to directly or another circuit goes to another panel switch that allows me to switch to either VHF distribution over here or to HF distribution over here.

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Above that station distribution shelf is an accessories rack shelf that includes a system to power laptops that I no longer use in the van, but that this was a big help when I was transitioning off of laptops into a permanently installed computer.

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On this side are the three connection blocks that I talked about in the previous circuit diagram.

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This is the direct station battery unregulated, 12 volts from the station batteries that go to the PC.

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This power pole distribution block is the unswitched power that goes to things like radios that I need for both HF and VHF and here as you can see on the label is the power pole distribution for VHF only components like transverters.

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Now I'd like to talk about the build out of HF and 6 meter amplifiers.

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There's a series of photographs that show the build process just as an example of how I built these things out for better or worse.

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00:32:55,240 --> 00:33:02,800
The HF amplifier is an Amaritron 500N amplifier which produces about 400 RF watts.

247
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This is the side of the distribution that supplies HF only power poles for other lower current devices and we're going to see a series of construction pictures next.

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Here's the amplifier mounted using a piece of angled aluminum where I screwed in the screwed in the aluminum into existing screw holes for the cover of the amplifier and then the vertical bolts bolt down into the rack shelf.

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After the amplifier I put in wood in the other spaces in order to mount the rest of the system here and use for future items here which turned out to be the 6 meter amplifier that I'll talk about.

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Here's just mounting the main components in the back and here we are wired.

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Here's the high current connections to the amplifier through these MIDI fuses and one more branch goes to this small power pole distribution and you can see this unusual connection of just the positive side.

252
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This is the bias voltage which is a separate wire that goes into the Ameritron amplifier.

253
00:34:28,820 --> 00:34:37,420
And finally this is the system actually mounted in the van with all the connections.

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Here is a remote probe for SWR and RF power that I connected to the output of the amplifier.

255
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Here's several of the HF only components including this screwdriver and that probe.

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Here's a PTT line from the amplifier to hit the relay during transmission for the amplifier.

257
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And finally here's the power input into this shelf from the station booster shelf, the picture of which I showed earlier, with two 4 gauge cables that go down to that other shelf.

258
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Now just this week I installed a 6 meter amplifier that I had for a long time and a 50 volt power system.

259
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So the amplifier needed 50 volts and I decided to supply that with my first big lithium battery and also built a switching monitoring and inrush board that I'll show later.

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Here's the mount board for the 6 meter amplifier that I used to help tie down that amplifier.

261
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The legs go into these glued down PVC caps.

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I have four eyelets for small bungee cords to constrain the amplifier vertically and these are four countersunk holes so I can put wood screws into the piece of wood that's below this mounting board.

263
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And here's the amplifier mounted next to the HF amplifier.

264
00:36:13,520 --> 00:36:16,060
Now there's two years between these two things.

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I built this shelf with the HF amplifier two years ago and this was just this week that I put the 6 meter amplifier in.

266
00:36:28,150 --> 00:36:37,230
Here's a picture of that large 50 volt 50 amp battery with some of the tools I used for the connections.

267
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And here's what the battery looked like.

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Before I put the restraining boards in I put the battery in with the connector to make sure everything fit as I expected before starting to make cuts.

269
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And as you can see this is that AC distribution I talked about early in my presentation.

270
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And here is the box for the generator.

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So this little kind of cubby hole is otherwise wasted space.

272
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So although I had to turn the battery on its side it was a nice fit, a nice use for otherwise wasted space.

273
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That cable from the battery is mounted on a board and the board is mounted on the side of the van and this represents a connection point for the battery.

274
00:37:26,900 --> 00:37:32,700
This allows me to connect or disconnect the battery as necessary for my different operations.

275
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Here's the 50 volt power shelf that I built recently.

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This is a box that contains a shunt resistor for the metering system and a bolted down midi battery.

277
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And this is the cable for supplying the voltages to the battery monitor here in the front.

278
00:38:00,090 --> 00:38:08,110
This is all in a treasure box, a wooden treasure box from a hobby store, kind of hillbilly engineering I call it.

279
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But I can close this lid to protect all these different connection points.

280
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I'm kind of paranoid now that I'm 50 volts versus 14 volts.

281
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That can supply quite a shock.

282
00:38:18,750 --> 00:38:28,450
Over here, maybe the most unusual looking part of this system is these resistors connected in parallel, also mounted in a hobby box.

283
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This is for inrush current protection.

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What I saw when I used this amplifier several years ago was that there was quite a spark of very high current as the capacitors got charged up from the capacitors, the amplifiers got charged up from the battery.

285
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And that kind of big inrush of current is not good for the battery and it's not good for the connectors.

286
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So a feature that I included was an inrush current protection by forcing the initial current to go through a total of 16 ohms that limits the current to less than 4 amps.

287
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And then that rapidly degrades to allow me to give it full power.

288
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Two switches on the front, one to charge the battery through this conventional power pole connection.

289
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So the charger gets connected here and I have one position for the charge.

290
00:39:25,170 --> 00:39:36,230
The other position goes to this other switch, one position of which forces the current through the 16 ohm resistor for inrush current limitation.

291
00:39:36,230 --> 00:39:43,310
And the other position, number 2 position, is a straight connection into the amplifier without the resistors for normal operation.

292
00:39:43,590 --> 00:40:00,930
And here, this is a meter that I had removed to make room for this shelf and this was just simply a convenient place to put this meter that monitors the voltage for my booster and my battery for the 14 volt system.

293
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So this has nothing to do with the 50 volt system, it was just a convenient place because I have a limited amount of rack space.

294
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And lastly, here's the whole system configured for test.

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You can barely see maybe the numbers on the meter that shows instantaneous voltage amperage and shows overall amp hours and watt hours.

296
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So that's this meter glowing here.

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You can see the lights on over here at the amplifier.

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This is actually an HF dummy load that's supposed to go up to, as you can see, it goes up to 30 MHz, but I used it because I didn't have any other dummy load that could take that much power.

299
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It was a 1.6 to 1 SWR at low power, so I didn't want to fire this 6 meter amplifier up all the way.

300
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But I did verify that it puts out 20 times the power that's put into it.

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00:41:02,120 --> 00:41:06,640
I tested it up to 600 watts with a FM carrier, so I'm satisfied.

302
00:41:06,640 --> 00:41:13,200
It basically works and nothing smoked, so it was nice to have that first test go well.

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I have not yet installed VHF equipment, although my VHF equipment is battle-tested.

304
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I haven't installed the shelves, but when I do, each band will be on one shelf.

305
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Each one will include a medium power amplifier, which I kind of referred to earlier in a power distribution schematic.

306
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I'll have a digital SWR meter for probes for each band, so I can see the power going out of each amplifier.

307
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And, as I mentioned, all the VHF equipment is already contest-proven, so I have confidence that the equipment I have will work.

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It's just a matter of mounting it.

309
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The 10 meter or 28 MHz IF that goes into the transverter port will come from the milliwatt output of the FlexRadio 6500.

310
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And I'll probably have a manual switch for selecting which band gets that IF initially, but I do want to install an automatic switch so I can select the band from the radio and have the IF switch through a relay.

311
00:42:32,040 --> 00:42:36,240
And I have those components, but I want to do one step at a time.

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It was good to talk about the power first, but next I want to talk about the radio and computers in the van.

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When I first started, and I made major assumptions about power systems, I originally aimed to use the Flex5000, which was my first 100-watt radio that I used at home.

314
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It's well-suited because it has transverter outputs and multiple RF and PTT outputs that you'd expect from a flagship radio.

315
00:43:11,280 --> 00:43:21,400
And the need for a good, powerful PC for this SVR drove the decision originally to use AC power for the van.

316
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Now what happened after I installed the entire AC system, one of my VHF club members offered a new generation Flex6500 for a surprisingly low price.

317
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That latest series from Flex radio includes self-contained computing power, so you don't need a big PC.

318
00:43:42,540 --> 00:43:53,880
Got fantastic programmable interface for driving relays, that makes some downstream work a lot easier than it would be with any other radio that I know of.

319
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It also has the same transverter and multiple programmable PTT outputs as my 5000, and lastly, not a big thing, but it's nice that it directly supports rack mounting.

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So I did buy that even though I made a lot of expensive decisions that were the foundation of which were the assumption I was going to use the Flex5000.

321
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So I now have a Flex6500 in the van.

322
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And here it is, mounted.

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Here's the front of the radio, which currently most of that is obscured by my monitor, but I do have access to the power button, that's the most important thing.

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And here's the connections to the headphones and the foot switch.

325
00:44:38,920 --> 00:44:41,360
And here's a view of the rear of the radio.

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It's not the flagship of the line, but it has enough connections to make things worthwhile, and you'll see the most unusual connection for most radios is this Ethernet connection, and that connects to my PC in order to have a GUI for this radio, because you can see on the front panel there are no conventional controls like a VFO knob.

327
00:45:10,480 --> 00:45:14,160
Another radio I installed was the ICOM IC7100.

328
00:45:14,160 --> 00:45:19,320
That was my first mobile radio for both HF and VHF rover contesting.

329
00:45:19,320 --> 00:45:31,420
So it has HF , it has two VHF, well I guess three if you count six meters, three VHF or UHF bands.

330
00:45:31,420 --> 00:45:47,100
So it's a really nice, tremendous value radio and used as a backup radio, maybe an IF for the microwaves, maybe as a FM radio for just making contacts to the local repeater.

331
00:45:47,100 --> 00:46:07,300
Anyway, it's a jack-of-all-trades radio that turned out to be vital because an older radio broke when I was on a major rove in Canada and I was able to use that IC7100 in the rove, preventing a major disaster for that long trip.

332
00:46:11,280 --> 00:46:23,680
And this just shows that IC7100 under test and various components of that rack shelf where the main unit of the IC7100 is tied down here.

333
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This is PTT connections because it's a small radio so everything comes out of this multi-pin connection that allows me access to this.

334
00:46:33,940 --> 00:46:43,000
And this is an automatic screwdriver antenna tuner, which I really don't use that much, but I had it so I mounted it with the radio that it operates with.

335
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Now again, another decision that was based on originally wanting to use the Flex 5000 that needs a big PC was to get a desktop-class rack-mounted PC.

336
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I had this built by a specialist vendor who built PCs especially for that series of Flex radios.

337
00:47:05,630 --> 00:47:10,110
Now, with the new generation, the Flex 6500, it's overkill.

338
00:47:10,110 --> 00:47:15,130
I don't need anywhere near that amount of CPU power, but I already have it so that's what I'm using.

339
00:47:16,430 --> 00:47:22,510
Later on, I replaced the original AC power supply from the vendor with a DC supply.

340
00:47:22,630 --> 00:47:30,430
In other words, what I mean by DC supply is that it's a computer power supply, but instead of the input being AC, it's DC.

341
00:47:30,470 --> 00:47:36,310
That thing was expensive, but it eliminated the original need for the AC base station.

342
00:47:36,310 --> 00:47:44,110
And again, boy, I wish I made that decision a year before, because I spent a lot of time and money getting an AC base station built.

343
00:47:46,550 --> 00:47:58,070
That power supply accepts a wide voltage input, and that voltage accepted is within the range of the raw battery, so I don't have to regulate that voltage.

344
00:47:58,070 --> 00:48:05,350
I can just connect it to my batteries as is through, of course, a distribution system that I showed you earlier.

345
00:48:07,550 --> 00:48:17,910
This PC works great with the new Flex 6500, and also works with the older 3000 or 5000 lines, because it has a good firewire connection.

346
00:48:18,990 --> 00:48:36,830
Now, what I did was brought out the 5V and 12V from inside the PC to a connector outside for use of low current logic like Arduino boards or relay boards, rather than having a separate DC power supply for those components.

347
00:48:36,830 --> 00:48:44,630
So, I haven't actually used that yet, but that's going to save some rack space and possibly save some additional source of RF noise.

348
00:48:44,790 --> 00:49:02,690
And lastly, at least I have a video adapter in there that supports a UHD 4K monitor, not all built-in video systems of a PC without a separate adapter would support a high -def monitor, and that is a big deal to me.

349
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That's a big help.

350
00:49:09,620 --> 00:49:13,820
So , here's a rack-mount PC, the back of the PC anyway.

351
00:49:13,820 --> 00:49:19,040
Nothing very remarkable, except it does take a lot of room in the rack, and it's kind of heavy.

352
00:49:19,040 --> 00:49:30,840
And actually, one of my projects that I'm going to do shortly is to reinforce this, because I really should have some weight support in the back of this PC, rather than just laying it hanging from the front.

353
00:49:32,660 --> 00:49:48,820
And just to emphasize again, this is the power input to the PC, and that DC input power supply is supplied through these input terminals, where normally the modular AC connector would be.

354
00:49:53,670 --> 00:49:57,110
My computer monitor is a 4K monitor.

355
00:49:57,470 --> 00:50:01,550
It's kind of mounted kind of floppy, but I'm working on an improved mount.

356
00:50:01,910 --> 00:50:10,370
There's enough room for an SDR interface and many windows, and man, screen real estate is really vital in today's ham contest.

357
00:50:10,570 --> 00:50:18,130
You have chat pages, you have monitoring systems, you have your logger, you have a rotator control.

358
00:50:18,130 --> 00:50:28,150
So, all these controls are soft controls , so it takes a lot of monitor real estate space.

359
00:50:28,310 --> 00:50:30,110
Now, I use Samsung monitors.

360
00:50:30,110 --> 00:50:34,890
I used a smaller one before, and what at least they used to.

361
00:50:35,030 --> 00:50:44,290
I don't know what the situation is today, but many of the mid-range and above Samsung monitors use a separate AC to 14 volt adapter.

362
00:50:44,290 --> 00:51:00,990
I don't know of any other manufacturer that has a 14 volt input, so what's nice there is, I can replace the power brick that takes AC with a power pole connector, so I can directly supply DC voltage from my station supply as the input into the monitor.

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So , just a recommendation, if you want to run your monitor from station power, look into the Samsung monitors, and you'll have a little bit of simplicity in one less brick, one less source of RF interference.

364
00:51:22,170 --> 00:51:31,910
And here's a picture of the operating position, showing that monitor and the nice amount of screen real estate.

365
00:51:31,910 --> 00:51:34,030
This is an old radio they used to use.

366
00:51:34,030 --> 00:51:35,510
They used to use a Flex 3000.

367
00:51:35,510 --> 00:51:36,870
That's been replaced.

368
00:51:36,990 --> 00:51:42,850
And here's one of the most important things I ever bought, which was a battery -operated fan.

369
00:51:42,850 --> 00:51:49,190
And this is blowing right at my face, and it is the difference between operating in 90 degree weather or not operating in 90 degree weather.

370
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Remember, the van is off.

371
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There's no air conditioning in the van when I'm operating, so having that fan be able to blow on me is a huge help on hot summer days.

372
00:52:03,790 --> 00:52:11,730
Next, I'm going to go quickly through the progress I've made on microwaves so far in the van.

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Now, I was just starting to buy used microwave equipment, even in my minivan days.

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00:52:20,370 --> 00:52:32,150
That's kind of my normal pattern, where if I know I'm going to go someplace down the road, if I see an inexpensive piece of equipment being offered, I'll just buy it up knowing I would use it for the future.

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00:52:32,990 --> 00:52:52,490
Now, then a successful pack rat that's my VHF club's name, retired from roving, and he sold me his complete set of working microwave bands from 33 centimeters or 903 megahertz all the way up to 24 gig.

376
00:52:53,370 --> 00:52:57,070
They were put aside until I could work on them.

377
00:52:59,450 --> 00:53:05,950
I concentrated first on the lower five microwave bands, because they were interior mounted.

378
00:53:06,250 --> 00:53:22,410
Physically, the 33 and 23 centimeter bands were separate on two-tier wood mounts, and the next three bands were all on one long plywood board, so I had a project to separate all the equipment and mount them each on a rack shelf.

379
00:53:25,250 --> 00:53:29,750
Now here's those three bands on one big plywood board I talked about.

380
00:53:29,750 --> 00:53:52,550
What I did was, believe it or not, and I can't believe it myself sometimes, I put that big board on the... I did do a little bit of separation first, but here, because they're so close together, but I actually ran the table saw I showed you earlier, I ran that table saw to physically disconnect each of these bands,

381
00:53:52,550 --> 00:53:56,750
and then mount each band on a separate rack shelf.

382
00:53:58,550 --> 00:54:05,050
It's hard to see, but you can just barely see the outline of each shelf in this bottom row of pictures.

383
00:54:08,280 --> 00:54:14,400
And here are the first five microwave bands mounted in the fourth rack .

384
00:54:14,400 --> 00:54:20,760
This is the rack that you can see directly in when you first enter the side door of the van.

385
00:54:20,760 --> 00:54:23,620
So it goes 903 up to 5 gig.

386
00:54:25,040 --> 00:54:35,260
Down the bottom here are two 12-volt batteries about the size of a normal car battery, although they're deep-cycle AGM batteries, and their charger.

387
00:54:35,260 --> 00:54:40,040
So this is the basic supply for the power for the microwaves.

388
00:54:42,760 --> 00:54:44,640
And here's a picture of the rear.

389
00:54:44,660 --> 00:54:56,160
Not terribly interesting, and a lot of the mess of wires, those green wires and blue wires, are actually left over from the old van, so I'll probably be taking those out before making the connections on the back.

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00:54:59,080 --> 00:55:17,840
Power requirements of the micros included high current 26.5 volts, high current 12.6 volts for the four low bands, and of course all the bands require nominal 12 volts for transverters, etc., like most radio equipment does.

391
00:55:17,840 --> 00:55:23,480
And I had a requirement for 5 volts for TTL logic and USB.

392
00:55:24,640 --> 00:55:28,780
My peak power estimate was 250 watts total.

393
00:55:28,780 --> 00:55:38,900
Now one unusual problem was that these are, most of them anyway, are Class A amplifiers, so there's a large current draw whether or not there's RF applied.

394
00:55:38,900 --> 00:55:44,180
So one of my requirements is that I would supply power only when the particular band was selected.

395
00:55:44,180 --> 00:55:57,840
And the relays on my distribution board should energize with grounding of the 24 volt system, because that's the same procedure that's used for the IF relays I had.

396
00:55:59,120 --> 00:56:08,240
The control power supplies would be separate and I'd want to monitor the current and voltages in the system.

397
00:56:09,920 --> 00:56:13,740
So here's the board I built to meet all those requirements.

398
00:56:13,800 --> 00:56:33,340
Central to it, of course, are these two power supplies that have the two voltage outputs I need, 12.6 and 26.5, and they are powered from nominally 24 volts from the two batteries that are on the bottom, the two 12 volt batteries are in series.

399
00:56:33,340 --> 00:56:47,800
And the only reason I made that decision versus a 12 volt supply at higher current was that I couldn't find power supplies with these outputs at these currents at anything less than a 24 volt supply.

400
00:56:47,800 --> 00:56:49,460
Here are my meters in the front.

401
00:56:49,460 --> 00:56:51,900
I'll have a better view of that later.

402
00:56:51,900 --> 00:57:06,260
Yet another shunt resistor to measure instantaneous current and the distribution of voltage to the various components in the power supplies.

403
00:57:06,260 --> 00:57:17,460
Here are two relays that I used to switch in from the front panel, and here's my much smaller 5 volt power supply.

404
00:57:17,500 --> 00:57:24,400
Here is a self -contained, I bought this as one unit, self-contained relay board with four relays.

405
00:57:24,400 --> 00:57:32,680
This meets my requirements of only supplying power to the high current amplifiers when their particular band is selected.

406
00:57:32,680 --> 00:57:50,920
So you can see that there's two connections for 26 and two connections for 12 volts that are controlled by the relays, and then the triggers here that are 24 volts, the triggers are brought out in this smaller terminal strip.

407
00:57:50,920 --> 00:57:59,820
And over here, this is meeting my requirement for the distribution of plain old 12 volts to the various components like transverters.

408
00:57:59,820 --> 00:58:04,460
And these are all powered from, of course, the 12 volt power supply side.

409
00:58:04,460 --> 00:58:13,560
So, quite a lot going on in this board, and this took me quite a long time to lay out all the components, no less build it all out.

410
00:58:18,480 --> 00:58:21,200
Here's the front power panel.

411
00:58:21,420 --> 00:58:24,960
The analog amp meter is here.

412
00:58:24,960 --> 00:58:36,320
This is the battery monitor, the battery voltage monitor that has a little graphic that shows how much power is left, which is possible because they're AGM batteries rather than lithium batteries.

413
00:58:36,500 --> 00:58:49,180
Here are three switches for turning on the power supplies individually, and these are meters, digital meters that monitor the three different available voltages.

414
00:58:49,180 --> 00:59:00,040
The reason I went to all the trouble of having separate switches for the power supplies was to limit inrush current, so I could switch each power supply on in turns.

415
00:59:00,120 --> 00:59:13,120
I mean, I could have done it, I guess, in a more sophisticated way, but this was a simple solution to just flip, flip, flip, and limit the total inrush current to the system.

416
00:59:14,200 --> 00:59:15,360
And that's it.

417
00:59:15,360 --> 00:59:23,160
If you're watching this video live at DEF CON, I think we're going to have a live Q&A after this.

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00:59:23,160 --> 00:59:30,160
If not, if you're watching this video offline, you are welcome to write me at my QRZ email address.