[aprssig] HT-220 HT's for APRS

[Robert Bruninga]

> > Has anyone used the old motorola HT-220 HT's for a simple
cheap
> > APRS radio? I found a box full of them in my garage. 
> >
> > I remember doing one years ago, and the only rub was the
lack of
> > a PTT relay.  I think I might just use some diodes and 1/4
wave
> > line this time?
> >   
> Why would it matter if the unit uses mechanical relays or
electronic 
> switching for PTT?

Because it uses the PTT mechanical switch itself to switch the
antenna.  RF goes through the PTT microswitch.  You either have
to put in a relay or devise some form of electronic switch with
PIN diodes and 1/4 wave lines. (as best I remember it)...

Bob, WB4APR

> 
> 
> 
> --
> 
> Stephen H. Smith    wa8lmf (at) aol.com
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>