Aboard USN ships RX and TX antennas were often parallel and only 30-60'
apart. This was with WW2 and earlier technology. Transmitters were usually
in the 500 to 2KW input range. TBK, TBM, TBL, FRT were some of the series
designators.
Shore stations running 5-25+ KW used seperate facilities.
OT's will recognize the RAK/RAL and RBA, RBB, RBC series as especially
bullet proof.
In the mid 60's transceivers such as the AN/URC-32 began to take over ship
communication.
Carl
KM1H
----- Original Message -----
From: "Bill Fuqua" <wlfuqu00@uky.edu>
To: <g3rzp@g3rzp.wanadoo.co.uk>; <amps@contesting.com>
Sent: Friday, September 07, 2007 9:40 AM
Subject: Re: [Amps] crossmodulation in PA
> In the old days military sites had the receiving equipment and antennas a
> few miles away from the transmitting site to avoid a number of problems.
> Naturally receivers those days were easily overloaded by off frequency
> signals.
>
> 73
> Bill wa4lav
>
>
> At 04:46 AM 9/7/2007 -0400, Peter Chadwick wrote:
>>Over the years, this has been a well known problem on ships at HF,
>>especially where they run full duplex telephony. Not that many do these
>>days in the commercial field, but the military have a lot of experience of
>>these effects. Somewhere I've a conference paper given some 20 odd years
>>ago from the UK MoD people on the subject, which told how they traced it
>>on anumber of ships. I remember them having a problem because in some
>>cases, below a certain power level it disappeared abruptly.. Fortunately,
>>the characteristics of tetrodes generally make the transmitter a
>>negligible contributor, but the external environment is another matter.
>>Worse at sea, of course because you've got continuous corrosion!
>>
>>73
>>Peter G3RZP
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>
> _______________________________________________
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