[Elecraft] Re: Amp Keying Circuit

[zl1aih at ihug.co.nz]

David VK2NU wrote :-

Thanks for all the responses to this - much 
appreciated.

I'm afraid it was a simple case of me not reading the 
instructions on
the keying circuit.

The FL-2100B pulls 20v on its keying input, whilst 
the circuit for the
K2 is only designed for 5-12v !! This is clearly written 
on the
instructions with the circuit, which I neglected to 
read. 

Does anyone have details of a simple circuit I can 
build, so I can use
this with my FL-2100B ??

Again, many thanks for the all the replies !!

David, VK2NU

Hi David - go to 
http:www.qsl.net/icom/ampcontrol.html
There you will see two very simple and reliable 
interface circuits that will enable almost any amp to 
be keyed safely by almost any transceiver.
To take care of older (high keyline voltage) amps, 
use MJE340 and MJE350 (negative and positive 
keying respectively).   I built mine in old Colman's 
Mustard tins, two RCA sockets - powered by the 
amp relay volts - easy 10 minute job.<G>
Using the amp keying circuit by Tom N0SS, my K2s 
happily key an L4B, or any of the other amps in the 
shack.
Apparently Icom had a problem with keying relays in 
some of it's transceivers  - hence the need for these 
interfaces.
73, Ken ZL1AIH