Thursday, 16 June 2016

Clansman Manpack Collection - Almost Complete

Many thanks to a chap by the name of Andrew in Glasgow, who has supplied me with the remaining transceivers for my collection of Clansman manpack radios.

These are the PRC-349s that also arrived for me at work yesterday. Now, these have no practical amateur purpose, but in a collection of 1980s British Army Manpack CNR, it wouldnt be complete without them. Described as handheld (if you have hands like shovels) these would be seen strapped to almost every lance jack or full screw you saw on the news from Belfast or Crossmaglen.

The pair obtained from Andrew are ex- ACF, and are complete to CES. Both are physically and aesthetically in excellent condition, as are the ancillaries  which in this kit are single earpiece and throat mic, pouch, and flexible whip antenna. It was for these that I was carrying out the battery cassette mods last night.

Modifying the battery cassettes for these radios to use 8x primary AA cells instead of 10x secondary NiCd or NiMH required just the shorting across of two of the battery spaces, as can be seen above. This is a good use for off-cut resistor legs!

Im glad I did this mod, as otherwise I might not have noticed that one of them needed its fuse holder resoldering! In order to show which battery positions are to be left unloaded, ive marked them with a red dot

Eventually, after he evaded me for several hours, I managed to collar my lad Sam, strap one of these on him, and get him to air test them with me! Earlier today I popped into Wilko's and bought a load of alkaline AAs for them.

The other new to me radio is the PRC-350, already mentioned. Now, a quick check of this for the 'confidence' noise with it hooked up to a bench PSU showed promise, but putting ten C cells into the battery cassette (modified like the '349s for alkaline cells) failed to power up. Much scrubbing and scraping of terminals later, even using washers and foil to make better contacts, and I eventually managed to get a 15v reading from the terminals (breaking one of them in half in the process!). But on connecting to the radio, it still wouldnt power up, and measuring the terminal voltage showed a staggering drop to 7v!

Inside the PRC-350. Flexi in abundance
 A check on the bench PSU showed that the radio takes 150mA on receive. This really shouldnt be enough to hurt a bank of C cells, even el cheapo zinc chloride 'JCB' brand from Home Bargains! (where I also bagged another head torch for 30 bob). I started to have a suspicion that what I was seeing was some spurious resistance somewhere. So, I checked the terminal voltage of the ten C cells just laid end to end - 16.7V. Then I put them back in the cassette and measured its terminal voltage - 16.44V. Doesnt sound much does it? But its enough to show that somewhere there was more resistance than is healthy in a DC supply! And it turned out to be a badly corroded crinkle washer and screw holding the negative terminal! Some careful scraping later (yes I will replace these with nice shiny new ones eventually) and the resistance was eliminated, and the radio now powers up on battery

Electrically, it seems ok. Physically, apart from the very bashed paint, missing audio socket dust caps and worn labels, the only issue the set had was that the battle antenna socket was so badly worn that putting the antenna on caused it to turn and the antenna fall over! Luckily, when I replaced the socket on the PRC-351, I ordered several, and so that was quickly changed and now the antenna stays where its put.

I could do with the proper carry straps for this radio, but they are not essential.

In terms of man portable Clansman equipment, my collection now includes 2x PRC-349, PRC-350, PRC351/352, and PRC-320. That only leaves the PRC-316 (A16), PRC-344, and PRC-319. Of these, the 344 is a UHF air to ground radio of no use whatsoever. The 319 is a 10ch HF voice and burst data transceiver that sells for stupid prices, and the 316 isnt really a Clansman, just a very late Larkspur set. I think I have all the actual radios I want now. Just a few remaining ancillaries to collect!

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