[1000mp] SB-220 with Mark V

[Pete Smith]

At 08:44 PM 2/2/03 -0800, you wrote:
> > By the way I would use a KD9SV front end saver with the larger relay for
> > keying the SB-220.
>
>What is that?


It's a cute little box that has a low-voltage, low-current circuit you 
switch with your transceiver, which then switches the SB-220 with a 
heavier-duty relay.  It also opens the circuit to a separate receiving 
antenna, if used.  See http://www.radio-ware.com/.  For less $, you can get 
a "soft-key" circuit from Harbach Electronics (www.harbachelectronics.com) 
that does the same thing.  Either of these will save you from potentially 
damaging your Mark 5 by trying to switch higher voltage and current than 
its relay is designed for (see p. 35 of the Mark 5 manual -- at ~110 VDC, 
the relay circuit of the SB-220 is well beyond the ratings of the TX GND relay.


73, Pete N4ZR
The World HF Contest Station Database was updated 1 Feb 03.
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