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This is all basically correct: in military use, (back in the days of predictable, known frequencies for a particular job), a dipole would be pre-adjusted to work a distant station, and would be used on the BNC output before the ATU.? This used to work, with whatever power the 320 allowed up the antenna, which probably was'nt a lot, overall.
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Where the antenna was going to be less than ideal, or lower than it should be, it could then be rigged across the ATU output, as described, and some sort of peak achieved.?
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Although not part of the CES, there used to be locally made up 39pF, and 100pF HV "door-knob" capacitors, with well insulated croc-clips either end.? These were not specifically to improve the matching (although they got used for that purpose), but were intended for coupling the 320 into unknown lengths of wire, such as fences, telephone and power lines, operationally, as a field expedient means of getting a good length of wire up in the air and achieving fairly discreet sky-wave.
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There was a more professional looking gadget with the 319 CES (possibly made in local workshops, or adapted from foreign kit), which had a similar hefty HV door-knob capacitor, but was mounted on a ground-spike, and had a choke shunting the antenna to ground, in DC terms.? This had a really hefty croc-clip on the output, similar to that found on car jump-leads, which allowed connection to disconnected lightning conductors, and quite large diameter pipes, etc.
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This was for operational "field expedient" use only, and a very long way from Elf and Safety, but would be in places where it was know that there was no power anywhere, just dead wiring (if it had'nt been removed and sold by locals!)
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73
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Al
G8LIT/W4
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? From: "Military1944@..." To: Racal-manpacks@... Sent: Thu, September 23, 2010 3:51:48 AM Subject: Re: [Racal-manpacks] PRC320 and dipole? ?
In a message dated 22/09/2010 19:58:42 GMT Daylight Time, iain@... writes:
Feeding the dipole with coax from the transmitter output BNC is the correct : The trouble there Iain is that there no way of knowing the match as the metering is not in circuit,the manual states using the BNC and I guess they (the mil) must have just accepted the slight mismatch etc, after all, even a diploe cut for say 14.200 will be off at 14.250 so I think we just need to accept it.
There was a thread on the clansman_larkspur group a : Thats interesting as the mnual makes no mention of adding a cap, and none is carried in the kit, unlike the Ws19 cap unit.
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Anyway, out portable next week, will have a play, hi.
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cheers, Ben.
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