help me design a radio shelter

Be warned, computers can be RF noisy. They can also be affected by noisy RF. I used to be able to reboot one of the office computers with my handheld. Consider carefully your wiring plan. As far as ruggedizing any computer look into semiconductor ( hard ) drives. Not exactly cheap but fairly vibration resistant. Finally for a do-it-everything radio receiver, consider an older AOR3000 scanner. Not quite DC to x-rays but it works just fine. Very compact and can be computer controlled.

Thanks for the input...

In place of the sink, I think a good addition would be a dehumidifier, to keep the inside of the shelter nice and dry at all times, when it's in its travels or at home as well. With all the radio and electronic gear I plan to install, keeping the rigs dampness-free would be good not just to prevent shock, but to prevent corrosion.

Update, just so you guys don't think that this is not on my radar anymore.

It is very much in the planning and parts acquisition phase. I can afford the shelter here soon, the truck to carry it is another matter, but it is still ongoing. Last several years have SUCKED income-wise. This year looks a little better, so I am investing some time and energy looking for cheap sources of parts and material for this build.

Case in point: I just hit the first ham radio fest of the year yesterday, not much in the way of good radios there, some old boat anchor civilian stuff but the rest of the show was parts and accessories. I did get out of there with two vintage microphones, a rack mount for my Collins military KWM-2A transceiver, another rack mount project case, 4 large meters in good order, and a military multimeter (AN/USM-223, otherwise known as an ME-297). Also, building this project entail not just hardware, but printed material like reference books and how-tos, so I picked up a handful of good radio/antenna books.

In storage: started getting together stuff I need for the build, or I think I MIGHT need. Note the large radio racks in the back. They are standard 19" racks, made of aluminum, and donated thoughtfully for this project by SCSG-G4. When the S-280 shelter is finally here, and I'm laying things out, I'll get a better idea of how I can make good use of these racks. The rest of the boxes and crates you see are packed full of parts: electrical, hardware, radio, antenna, computer, manuals, and misc. So while I haven't been very forthcoming with build pics, as that phase hasn't happened yet, the search for the rest of the setup is well under way.

Forgot to mention, if you have some stuff available that you think might be worth saving for this build, please send me a PM. Let me know what you have, what you are asking, etc. Thanks.

Too bad you could not make this past GA rally. The Morgans had some good dehumidifiers for $20 each. With the outlet hose hooked into the floor drain the inside of the shelter would stay bone dry in a monsoon!

SCSG-G4 said:

Too bad you could not make this past GA rally. The Morgans had some good dehumidifiers for $20 each. With the outlet hose hooked into the floor drain the inside of the shelter would stay bone dry in a monsoon!

Click to expand...

$20 each is a steal - were they military surplus units or just used Kenmores? Any pics of what they were?

Whirlpool, 24 high, 13 deep, 12.5 wide. I bought two for some reason, they are still in the garage with some other stuff. Color is 'off white' and may be lighter if cleaned up. I was going to run one in the basement but have too many other things going on.

I'd say it was probably the biggest single hit of the rally sales wise. It certainly would have worked in a small shelter. Probably suck the moisture out of a human too.

Did you ever check back with OPCOM?
If you find a good AM2060 in your search for parts, let me know, please.

I recommend a PRC-515. 2-30Mhz TX and RX coverage. Available with frame, bag and harness. Slightly heavier than the PRC-104 but worth it. Comes with autotuner. The PRC-515 is from Canada but the GRC-220 is from the US. Both radios are the same. Manufactured by Rockwell Collins.

Went to Colemans Surplus on Friday, out in the 17 degree weather walking on crusty ice over 4" of loose snow. Very cold.

Worth the trip though, in addition to some other things, I found these lonely panels that came out of a telegraph relay shelter there, that had been attacked by a bulldozer. These were the only 19" rack items still in the shelter, the rest was either missing or crushed. One looks like it was a power distribution panel, the other a power relay bank, made by Stelma Inc.

Part of the interest in this project is using what parts I find to make new things, stuff that would be useful in this shelter build. For example, I saved two GIANT vacuum tubes, each over 14" long, at a recent show. They were bad, one lost it's vacuum and one has no filament voltage, however someone referred me to an article in an old ham radio magazine of how to turn a bad tube into a low-voltage lamp. So guess what are going to become rack-mounted safety lamps in this build? I also saw a recent article in QST magazine of how to salvage an old microwave and all it's components and build an RF amplifier out of them. Pretty neat stuff!

Anyways, how do these things relate to the theme of salvaged goodness? Well, unfortunately, these spent too much time outside in the moisture, most of the electronic components are either visibly bad, or suspect. So most of these can't be reused. But the rack panels themselves will live on, for the price I snagged these for, a low-value dead president, it sure beats buying a new panel for an inflated price elsewhere. Not sure what these will become, but suffice to say, more salvaged parts for custom projects.

Subscribed, love this thread - I want to build an S-250 shelter to put in the XM1027 when it's done, then build a camp support trailer for more, err - stuff. One project at a time though .

Any consideration for a DC generator rather than an AC generator plus a UPS? If you are hurting for cash, this may be easier on your wallet than a new Honda inverter generator. The make-up is pretty simple, think of it as a vehicle with an inverter attached to the battery, but no working drive train.

Engine-->Alternator-->Battery-->Inverter

Another hint from the Bus-Conversion/RV world: size your inverter to the loads you plan to use frequently, you can save some power by using multiple small/cheap inverters and running them when they are needed. If you have a fridge (mini-or otherwise), you can take a cheap true sine inverter sized only for the compressor on that fridge - then re-wire the fridge to run 100% of the time when plugged in, and wire the thermostat that normally runs the compressor into the power switch for the inverter. This way the inverter draws 0Amps when there is no refrigeration needed.

You can look at the loads you run during the day and over-night - size your battery bank to run the overnight loads and half of the day with a 50% discharge or less (your budget allowing), then size your alternator and engine to charge the battery bank and run your day-time loads with only a 4-6 hour run time required (or less if your budget allows). Vent your battery bank to the outside (important). You can put an electric start generator on an auto-start controller (cheap can be found if you are willing to go Chinese), and hook the auto-start contact closure into a cheap sprinkler timer - most electronic sprinkler timers use a 9V battery to run the timer and the internal relay will switch 24V, one cheap 4-6 zone controller can do all your timed lights, timed devices, and your generator. You can use a low voltage alarm relay in series with a sprinker-timer-relay to run your engine during day time hours only if the batteries are low enough to need a run.


As for computers, check out www.mini-box.com, this is a company that I buy parts from (not paid endorsement, my own opinion). These guys have a 275Watt capable DC-to-DC ATX power supply that runs from 6-34VDC and will continuously run up to a 220Watt PC platform. This way you can run a full Commercial-Off-The-Shelf desktop computer (or build your own compact Mini-ITX type). I like the flexibility of Linux, but I know that not everyone has the desire (courage?) to break from Microsoft... I like the boot from CD or USB drive option that Linux allows for - this means you don't need a hard drive at all.

There is a cool HAM voice compression codec (Codec2) and software digital voice modem that uses it (FDMDV) - I've always wanted to try it, but I need to take my tests first...

If you are going all-out on communications, the newer VIC intercoms (Vic-3/Vic-5) use Session-Initialization-Protocol (SIP) which is a Voice over IP (VoIP) network protocol. An SIP phone plus a Linux based Asterisk VoIP server with some sort of data connection (2G/3G/4G) would be sweet. If you wanted to do tent-to-tent intercoms and calls at camps/gatherings/conventions, you'd just need to drop Power-Over-Ethernet VoIP phones in the tents and drag Cat-5 back to your shelter and flip the switch on the server (no internet connection needed). This is the way the currently deployed stuff is moving. You could spend money and do a PSTN IO card and let people plug their 2-wire field phones in too.

Hey Tim,

Thanks for all the great tech info! However, some of that gear I haven't really thought of incorporating into this build. I see no need for VIC-1/3/4/5 communications in this rig, if this were a crew setup where there was a driver up front and someone in the back, maybe. But this is only going to be used by me, when the tow vehicle is stationary. For local comms with tents/other shelters/etc., like at a rally where I want to communicate without leaving the shelter, I am more familiar with the TA-312 field phones and SB-22 switchboards, run some WD-1 field wire to where you have to go, and your network is done.

As for inverters, once again, this setup will only be used when stationary. Most of the gear inside will require 120VAC, so an AC generator makes more sense. Yes, I know a lot of civvy gear requires 12 VDC, and the wall-wart converts 120 VAC to the 12 VDC, but that's why there are wall-warts. However, one thing I wish to incorporate is a battery back-up system, where the AC genset charges a bank of 12 VDC deep-cycle batteries, and if the genset runs out of gas, or is off, I can still run some of the gear inside. Not all, but at least a small radio or the computer, things that won't draw too much amperage.

I mentioned the VIC systems since they to are using SIP now, it would be compatible with a SIP VoIP server like Asterisk (think of Asterisk as a drop in replacement for the SB-22). The TA-312 phones are also compatible with the Asterisk server as-is with the inclusion of the analog card(s), but there is even a TA-955 touch-tone adapter for the TA-312 (I see a few of those available right now on e-place) which would make a field phone as handy and functional as a line-man's handset. The biggest draw-back in my mind about the SB-22 is that it requires an operator, and one who is awake when you want to call in. You can configure Asterisk to give you a voice directory (text-to-speech, and speech-recognition), or to "hotline". I put this out there since you have your HAM ID in your signature, there is a way to configure Asterisk to connect you to a radio rather than a phone extension, so in theory you could pick up your phone, punch in the number for the radio, punch in your frequency once you've connected, and you can QSO using a phone (analog, digital, VoIP, etc...) to operate your radio as a remote console.

I understand your interest in using this while stationary, my recommendations come from the point of view of total installed cost, ease of inter-connection, energy efficiency, and after-the-fact functional flexibility.

One thing to keep in mind with the energy efficiency aspect, is that every conversion costs you some waste - going from gas/diesel to rotational energy (~30-45% efficient), from rotational to 120VAC (~85-95% efficient), going from 120VAC to 14.4VDC (~85-98% efficient), charging a lead-acid/AGM battery (~80%), going from 12VDC to 120VAC (~80-90% efficient). Assuming you were powering a 500Watt load through that whole chain of conversions means you are demanding about 750Watts of energy from the output shaft of that engine (assuming the highest efficiencies I quoted), and it's actually going to be worse than that if you can't afford the super expensive high-efficiency gear. And if a device adds another step to go back down to 12VDC, you're just wasting more battery life heating a wall-wart up .

The 12VDC or 24VDC (I personally advocate for the NATO-24V route) system means that you only need to power those devices that require 120VAC by design with an inverter. Everything else skips that conversion. It also makes it easier to mix an match power sources and supplies - if your system ran on 24VDC primarily, you'd just need to put a NATO slave plug on the outside of your enclosure - power it from your truck, or someone else's truck in a pinch (I'll bet you can find one of those at any rally or gathering ). Put solar panels on the roof of the shelter, hook up a 24VDC solar charger direct to your slave port, and charge batteries without a sound (both the enclosure and your truck by the way). What you save in weight and cost for the generator and fuel that way can go directly into bigger batteries.

These are just ideas and ways to think about this - not intended to discourage, but rather to ignite imagination.

Can't wait to see this done, any way to do it .

Any updates????

Not recently, don't you worry - when I have some more development on this end, I'll be happy to post pics and more info when it happens. For now, it's on hold while I am working as much as I can this summer, once the weather cools, my work will slow and I'll have more free time to build toys.

Thanks. I want to build a radio shack in a S280 or a M1010 ambulance.
Subscribed

I'm working on a shelter as well. Im incorporating a 40' pneumatic mast and pumps from an old TV remote truck and 2 25' Hurry Up masts to support antennas. Have most of the parts, just need money and time for final assembly.

Just a small update to this thread - went to Gilbert PA show last weekend and had a great time. While my funds were low, I still was able to manage to find something for the shelter project. One seller had this rack mounted storage cabinet, built for Tobyhanna Army Depot, CY(7181)/G. It latches, but is not "locking" per se, I'm not sure if that might be an option if I modify it a little bit. The storage cabinet fits standard 19-inch racks, and is in good physical condition, cost only $10. Would be great for the shelter, to hold manuals, headsets, etc.

The only official information I can find on the original use of the storage cabinet, states it was for Data Analysis Center, AN/TYK-10, basically an S-250 shelter with a radio/signal intercept package.

Mike,
Sounds like a cool project, as net control for the West Coast Military radio group for many years, and an interest
in fairly current radios, I own and have operated most of the recent HF radios used by the military in the last 30 years.
One of my favorites is the GRC-193 series radios, 2-30 Mc, 100 or 400 watts,USB/LSB and has RTTY capability. This system is designed to be used with the AT-1011 antenna system (vertical) in both a mobile or stationary situation, only requires about 45amps at 24v, it really likes 26.4v, but that should not be a problem for you. I have many cross country contacts with this radio on the AT-1011 with a good ground radial system. This is an 1980's system used up to the early 2000's
Big plus is that it does not cost an arm and a leg like the RF 5020-22 Harris equipment, and has been very dependable
in the last 6 years that I have used it. Check it out on the net and or contact me I am good on QRZ.

73's
Jim Beeler KE6ZIQ aka halftrack-m-3