You might also try using a Darlington pair transistor to get more gain and
isolation from input to output. I cant remember the number offhand, but
it's a 3Nxx I think that comes in a typical plastic package the same size
as a 2n2222, etc. There is a PNP and NPN version as well, and they are
CHEAP!
73, Ty K3MM
To: n6tr@teleport.com, trlog@contesting.com
cc: (bcc: Tyler G Stewart/BENN/CEC)
Subject:
> Anyone else had any problem with optos not keying the VOX on their rigs,
> but keying the CW just fine? That's what happens on my TS-930 --
> fortunately I also use TR's PTT function to avoid hot-switching my amp,
and
> that works fine.
I have seen this with my 850. It was typically fixed by making sure
I had a good connection with the DIN plug that I was using to connect
the PTT signal to the radio. It probably was also due to not driving
the transistor hard enough (which is why I went to using dry contacts
in the switch box).
> I would like to be able to use DX4WIN's CW keyboard, though, which does
not
> have the PTT function. I'm guessing that this problem is like some of
the
> early solid-state keying circuits, that wouldn't key some rigs because
they
> didn't pull the key line all the way to zero. I'm purely a cookbook
> technician, and would appreciate any ready-made wisdom as to how to fix
> such a problem.
You can probably fix this by putting a 1.5 volt battery in series with
the key line. Put the positive end on the transistor side and the
negative end on the radio side. I haven't actually tried this, so
there might be some side effects that I haven't thought of.
Tree
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