measures wrote:
>
> > The circuits to work with PIN diodes are much more
> >complicated
> >than with relays, but if you need the speed...
> >
> Indeed. For super speed cw, PIN diodes are the only game in town.
I think the speed you need depends on whether you can get a good early
'transmit' signal from your exciter. I've used the vacuum relay / reed relay
circuit on Rich's web site successfully in several amps now, with driving
voltages of 65 to 150 volts. I have been unable to detect hot switching, even
while sending 55 wpm dits. I've keyed these circuits using the +12v on transmit
line from the TS850s -- not the ptt relay -- and a similar signal from an
Elecraft K2.
I've used the HC-1 relays in these circuits, rather than the RJ1A's. I believe
these have proven more durable in this service. I've not had any relay
failures, although I don't tend to operate 40 hours straight running stations in
CW contests, either!
73,
Vic, K2VCO
Fresno CA
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|