[WT-support] PTT keying

[Olivier F5MZN]

Stewart GM4AFF wrotte:
> Apologies if this has been asked before. Is there a circuit for and an
> explanation of the PTT functionality built into WinTest for use with COM and
> LPT ports? Ideally I would like a little circuit not just for keying the
> (LPT pin 17) CW (as in the Wiki) but also showing how the rig PTT could be
> closed by (LPT) pin 16. Also interested in how this functionality is adapted
> to cope with laptops which only have USB ports (which adapters work, which
> don't, etc).

As stated by Filipe CT1ILT, I have never been told that any USB to LPT 
converter is supported. Most of the time, that kind of adapters are just 
designed to work with a printer and only with a printer.

On the other hand, most (but not all) of the USB to Serial converter are 
OK. Then a couple of transistors+resistors (or better an opto-coupler) 
can be used to control both PTT and CW. This is the cheaper way.

If you don't want to bother with technical problems, the microHam 
products are perfect. They include all the needed stuff to control both 
PTT and CW and much more according to the model. Sure it costs a bit 
more than if you build everything by yourself, but you have a waranty 
that it will work perfectly. In addition, you can save lots of your 
precious time!

HTH

73,
-- 
Olivier / f5mzn