So, so far we've talked about which of the Clansman series manpack radios are suitable for amateur use, what you'd need to get one powered, and how to actually listen and talk on it if you have one (I offer no guarentee that theres anyone listening!), so all thats left is to discuss the basics of antennas for them.
Now, as these are the man portable radios, the antennas i'll mention are also man portable. The general operational doctrine in the field was usually that, with the exception of inter-section comms, the manpack would be talking to either a vehicle mounted system, or either a fixed or field commcen (communications center) which could be a couple of 12m masts and tents, an RN ship, or something a little bigger like DHFS Forrest Moor with its huge HF log periodics. The onus often, especially for HF, being on the more capable station taking the brunt of the link.
I'll start with the PRC350, and move on 'up the chain' as it were
PRC-350 Antennas
The PRC-350 has a bayonet fitting antenna socket for what are termed 'battle whips'. There are two common types, with corresponding differences in performance. The first is a 'rubber duck' type flexible 60cm helical antenna. This has an advantage of being pretty much indestructable, but of course not a great range! More useful is the 1.2m sectional whip. More rigid, but with a sprung ball and socket mounting, this comprises four tubular sections attached with an elastic cord.
0.6m flexible battle whip |
1.2m sectional whip |
Both of these are ok if your actually carrying your PRC-350 on your back or hip. Often available for very little money, but probably of very limited use, is the 'trailing wire' antenna. This is a 1.2m long length of braided antenna wire and a bayonet connector. Its tactical use can be appreciated, but for amateur purposes its little more than a curiosity.
Trailing wire antenna |
So those are your usual antenna options for the PRC-350. Doesnt give you much leeway for your 2W does it? But, you may have noticed your radio has a dinky mini-BNC socket on it. We'll see why shortly,
PRC-351 and -352
The higher powered PRC-351, with its thobbing 4W, also has the same bayonet fitting antenna connector as the -350, and so can use any of the above antennas. But, it also has a BNC connector. This BNC is to allow you to use it with the big brother antenna, the GSA (Ground Spike Antenna)
GSA Kit |
The GSA antenna is essential if you have a PRC-352, as this cannot be used with the battle whips.
Have you discovered the odd 40cm coax lead that came with the kit? Yep, thats the adaptor for the mini-BNC on the PRC-350!
The GSA is not too bad an antenna, but its still rather low down. VHF likes height, so another kit is available, the EKGSA (Elevation Kit, Ground Spike Antenna). Supplied, hopefully, in its own carrying satchel, this kit comprises all you need to mount the GSA on top of the 5.4m mast (of which more later), or to hang it from a tree or other suitable support. The key to it is the set of measured coax cables and the mast mounting inductor unit. These between them provide an artificial ground for the GSA.
EKGSA kit |
To use the EKGSA at height, if you dont have a nice tall tree with spreading boughs, you'll need a mast. The EKGSA (and many other antennas for the HF side of things) are designed to be used with the 5.4m Fibreglass mast kit.
5.4m Mast Kit |
Im going to put HF antennas in their own post, as theres more options there than with the VHF kit.
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