Decided. I'm going with the three relay solution. I found some "reed" type
relays with specified ~1ms switch times and 10^7 cycles lifetime. All
SPST. When receiving, power will be applied to the relays. One relay(NC)
will disconnect the transmit antenna, another(NO) will connect the receive
antenna, the third(NO) will connect the "detuner" to the transmit antenna.
I'll post a photo somewhere when it's together. Now that that's sorted and
the relays are on order...there is another problem.
The separate RX antenna was prompted by a desire to hear better on
160/80/40 and the assumption that RX noise in my Eagle was from the
external environment. It appears that my assumption was partially wrong.
Initially I blamed noise on a MFJ power supply. The MFJ was indeed guilty.
The replacement(same model) does not produce hash every 35kc. Once burned I
was still suspicious of MFJ. I decided the only way to settle was with a
known quiet power supply and purchased a deep cycle battery.
I still have a nasty bunch of hash around 1900kc(about 1895 on power up and
it drifts up to about 1905). It is there, even with the Eagle connected(by
18" leads) to only the battery. The hash is a strong S7 to S8. I can hear
it on my Drake R-7 and a Radio Shack labeled ATS-505 by placing their
antenna close to the Eagle. When I turn off the Eagle it goes away.The hash
is clearly originating inside the Eagle.
Has anyone else run across this noise? If so, solution?
I will be calling TT on Monday.
Here is what it sounds like.
https://www.youtube.com/watch?v=06FbT3vuRUc&feature=youtu.be
Thanks
73, Bob AH7I/W4
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