> Mike Morris <wa6...@...> wrote:
> The idle marker tone system was designed for wire-lines
> and adapted to microwave shots.
Also known as "Status Tone"
> But there are ways around it. The simple method:
> Have a local 1950 oscillator at the voter site. It can be done
> with a 88mh toroid, a few resistors and caps, and a single
> transistor.
Can't think of the last time I saw an 88mh Toroid for sale in
any obvious location but I'm sure they're out there somewhere
like Ebay. I found some of the newer one-chip GE Status Tone
Encoders on Ebay a few months back and they were cheaper than
I could have easily built them for.
> Have a SPDT reed relay driven by the link receiver RUS (or COR).
> Links can be on 420Mhz, 438-439Mhz, 900Mhz, or 1200 Mhz.
... and if you're creative some other places.
> The NC contact on the relay has 1950hz. NO contact has link
> receiver audio. Armature feeds voter card audio input.
> When channel is idle, card sees 1950hz and is happy.
> When channel is unsquelched card sees link receiver audio
> and votes.
Wonder if the relay pole contact transition time contributes
to any type of glitch, hunt, delay or erratic event that might
otherwise not be there if you simply (resistance as an example)
mixed and removed the Status Tone?
> Reed relays last a long time - I've had used ones last 12 years,
> and new ones last 20, but you can use CMOS audio switches if you
> want.
CD4053 and use the diagram from an ACC RC-85 Repeater Controller
as your basic guide.
> The GE voter performance has the Doug Hall beat hands down.
The GE and Motorola Spectra Tac Voters are true Signal-To-Noise
Voters, where as the LDG, earlier Doug Hall and the ARRL 2-Channel
voters are not. I haven't seen a current Hall Voter Close up to
determine if it's a real SN Voter but the earlier Hall versions
I have like the LDG are not (true SN voters).
True SN Voters don't seem to be nearly as subject to "talk-off"
as do the lower cost voter options. But the lower cost options
are quite usable. One novel trick with the LDG Voter is to use
the inputs for all your repeater receivers when the controller
doesn't have enough RX ports.
> Documentation on both vintages of the GE voter (grey paint is
> early, black paint is late) is on the GE LBI page at repeater-
> builder.
> Mike WA6ILQ
The Spectra Tac Voter Manuals pop up on Ebay every so often as
to the GE Version Manuals.
If you "fool the status tone decoder" with a local oscillator,
keep in mind the level of the Status Tone also plays into the
actual performance. It's not just a "tone present" or "tone not
present" function.
s.
