Thanks Guys,
To the many of you who sent circuits, suggestions, formulas, etc.
The problem was solved by a combination of main strength and
awkwardness, as my Grandmother used to say.
Dave provided the clues needed to solve the problem when he said:
> OTOH, if the voltage drop across the keying transistor and pin 1 to > ground
> may simply be too high for your radio. You can confirm this by > taking an
> assortment of resistors and finding the highest resistance > which will key
> the radio. Measure the voltage drop across the keying > line with this
> resistance and see if its lower than the voltage across > the keying
> interface.
This check revealed that the voltage drop across the keying transistor
was .88 volts and it required about .3 volts to key my transceiver.
This was the problem Dave described. The .88 needed to be less than the
.3.
Several of you had suggested changing the value of the 1K base resistor
to the 2N2222 keying transistor. Most said lower it and one guy said
raise it. This, of course, would be the simplest mod if it could work.
And, I believe in the old saw, "keep it simple, make it fun".
I tried a range of values, and found that the voltage drop from the
collector to ground varied inversely to the resistor used.
At 22K in the base lead, the K2 rig keys normally with NA.
I will leave it to the experts to explain *why* it works. :-)
And, thanks again to all who contributed!
--
73,
Bob Kellogg, AE4IC
Prolably, not nececelery. -Benny Hill
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