A while back K6XX published an article that can be found at
It is a simple opticoupler that triggers a 555 timer base on the voltage drop
across a resistor.
I built the circuit but only connected pin 2 to the 100k resistor from the
It has different levels of working with different connections I have tried.
Grounding the relay jack will key Q1 if the output is low, but it starts high.
At one point I could vary the voltage in to the opticoupler and trigger the
555. Also, the time delay worked too. Now I can't get it to do much hi hi I
need to start over.
I'm a tube and voltage guy and almost nothing I've built SS except for a 160
meter surface mount SDR and my copy of the Alpha 78 QSK board has worked first
time out hi hi
Can someone look at the schematic and let me know what the problem is, IE
I can see the trigger tied to B+ and do not think that is correct.
I assumed pin 4 needed to go to B+, maybe not.
I made a PCB and it is a pain makeing changes and cutting foil.
Please, any help from you solid state guys? My 8874s need you. K6XX does not
Talk is cheap... except when Congress does it.
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