Monday, 15 February 2016

Clansman PRC-351 Antenna Connector

The Clansman PRC-351 VHF manpack is designed to be used with a 1.2m whip antenna, for which it has a special multi-angle antenna connector. Unfortunately, on my set, this is badly worn, such that the antenna will not stay up in position, but can overcome the position indents under its own weight and fall down.

It occurred to me that it might be possible to repair this internally, so today I removed it from the radio to open it up and take a look.

The above photo shows the dismantled antenna connector. The main boss uses a pair of plastic inserts that are pressed into the notches on the body by a semicircular spring clip. These inserts were worn almost flat on the face towards the body.

Turning them around and reinserting them, at first glance it looks like it will be a good repair. Next job was to brush out all the dirt, dust and powdered plastic insert!

With the connector cleaned, I reassembled it, and replaced it in position on the radio. A further task for the future will be to either replace or repair the antenna contact in the radio which is rather loose.  Reassembling the connector was a simple reversal process, making sure not to loose the little O ring or the two washers. If I was going for a full CES rebuild, then I would have followed the old soldiers adage of 'always grease your ring' when replacing the two O ring seals.

Sadly, after refitting the connector to the radio, it was found that the antenna will still drop from position if knocked or shaken too much. It is tighter than it was, but not sufficient to use the whip antenna with the radio on the back. Luckily, PTSNorfolk stock these connectors, so ive ordered a couple of replacements.

Two packages have just arrived, which despite their small size seemed to give the postman trouble getting through the letter box! One is the PCB for the EPE Theremin, which im building on behalf of a work colleague. The other is an Arduino Uno board, and a 'getting started' book, courtesy of Steve G7TAO, for Sam to use to learn more programming techniques. As Sam has a friend over to play today, im going to have a bit of a read!

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