Raj,
Thank you for the response. You confirm my fear that the danger of damage is real and present.
I am very much a beginner at this sort of work. I have excellent mechanical and soldering skills, but know little of circuit elements beyond what was required for my license.
I believe you have offered two possible ways to mitigate the risk - either the diodes OR the incandescent bulb. Correct?
If I choose the diodes in parallel, I assume one lead of each goes to pin 12 of K1 relay. Does the other lead of each go to ground? Or where? Be gentle please!
If I choose the miniature bulb, does that bulb function as a sacrificial element like a gas discharge arrestor cartridge? Or is it able to absorb and limit the voltage? I can do either, and it seems you are saying the second option is better.
I’m learning as fast as I can!
toggle quoted message
Show quoted text
Thomas,
At pin 12 of K1 relay solder 2 4148 diodes in parallel but in opposite polarity. This will limit the receiver from getting high RF voltage.?
Also if you cut the track between K1 pin 12 and K2 pin 14 and insert a 12v 60 or 40 ma miniature incandescent bulb it would be better. This is common protection method in commercial transceivers and amps. This track seems to be on the component side.
?
cheaper still!
?
73 Raj vu2zap
At 17/12/2016, you wrote:
??
How likely is this to happen? Bitx40 connected to 40M resonant antenna perpendicular to another antenna with a 100W transceiver running a Winlink gateway.
I fully expect front-end overload and nasty noises, but will the coupling cause actual damage> I would like to leave the bitx40 running but volume minimized to lessen drift during warm-up period.
Currently I leave it running but antenna dis-connected, but it is only a matter to time until my feeble brain forgets.
Thomas W Noel
KF7RSF
