On Feb 17, 11:25*am, "Ross, NS7F" wrote:
This is with regards to a medium-power (~50W) CW transmitter that I am
building for 40, 20, 15, & 10m. I would like to use relays to switch
the output filters, but have no idea what kind of relay I will need.
Dr Sabin mentioned that a high-quality relay is required (http://www.google.com/url?url=http:/...f03/t/3d5e036f...
) but I have been unable to find anything specific. Could anybody
please direct me to a resource that would help me answer this
question? Thank you very much.

For reference, the transmitter is a redesign of the classic '60s
"inexpensive 75W transmitter", originally by Lew McCoy (I believe),
one version of which can be found at (http://www.mines.uidaho.edu/
~glowbugs/inexpensive75wattxmitter.pdf ). It is a simple crystal-
controlled 6AG7 followed by an 807 amplifier at 75W input (50W
output). The filters are from Ed Wetherhold's article- (available athttp://www.arrl.org/tis/info/pdf/9902044.pdf) 7th order "Chebyshev
With Added Zero" to give better second harmonic attenuation.

Best regards,
Ross, NS7F

My friend used to do something similar at the antenna and using SPST
contacotrs that were used to switch an air conditioner compressor on
and off. Three of these could easily fit under a Pi-net coil. Ill try
to find picks and part numbers.

Jimmie