Tony,
My apologies. I re-read your email and see your dealing with receive
only antennas.
You may ignore my post, as current/voltage will not be an issue.
I had always heard the reactance should be 10 - 12 times the impedance
your dealing with, so at least 600 ohms reactance for the choke, which
is about 50 uh at 1.8 MHz. Easy to go more and doesn't hurt. I think I
use 75 to 100 uh. I don't recall exactly.
The cap can be almost any amount. A .01 uf will give your about 5 ohms
of capacitive reactance at 160.
Steve, NR4M
On 4/3/2018 9:32 AM, N2TK, Tony wrote:
Have a question about the values of the choke to keep RF from the relay and
the caps for coupling of the signal. In different products I see quite a bit
of different values of both components.
For the coupling caps I see values from .01-.2uf. It would seem increasing
the value of the cap reduces the Xc. And for the choke I see values of
100uh-2.5mh. And it seems increasing the value of the choke also increases
Xl.
My application is for 160M and 80M only with receive antennas.
My question - does it really make a difference over the values listed above?
Do all the values offer enough Xc or Xl to not cause any problems? Is there
really a recommended "good" value for the caps and coils? Even 100uh offers
1K ohms at 1.8MHZ and .1uf is .8 ohms.
Still learning.
Tnx
N2TK, Tony
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