I have yet to see a modern rig that does not have an 8 volt or 12 volt
output line on the accessory jack that is active in TX... I use this
line froom both my TS450 and IC-745 to drive an external Switching
transistor that keys the relay ,that gets it's 12v from the P.S.... a
very simple but effective ckt right out of the handbook... total cost to
me was 5.00 for the cabinet with a dpdt switch (junk box) for switching
between rigs an LED (junk box) to indicate the amp is keyed.. and 4
(junk box) RCA connectors for 12v in ,TX high in(2) and Key out... I use
this to key my SB-220 and have no problem with this arrangement .This
draws very low ((1-2ma) from the 8 or 12v TX line from either rig... If
you wanted to further protect the devices have the first transistor
drive a second transistor for isolation ... total cost was about 8.00
and about 1 1/2 hours work...73 de Jordan VE2SWL/VE6...
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|