Batboard

Hi Group,
Question. I'm sure it's addressed in the manual (which I have), but not adequately enough for me to understand it.

I have a Motorola MSF 5000 (CXB Digital Type) UHF repeater. Attached is a Motorola SpectraTAC comparator equipped for 3 voting channels (3 SQM's), a Command Module and a Tone Keying module. I'm running tone control between the MSF 5000 and the comparator.

I have the MSF 5000 configured for 4-wire operation, with the signalling and audio from the comparator to the repeater on Line 1, and the receive audio from the MSF 5000 receiver on Line 2 going into SQM #1. This allows me to vote the internal receiver on the MSF 5000.

There are two other SQM's, one has a SpectraTAC receiver on it which is located elsewhere and linked via wireline, and one spare (I haven't connected the other receiver yet, but I have it). So I'm voting a total of 2 channels with the spare in manual disable.

I would like to add a Motorola T1600 series tone control console to the mix. I understand I can use a Tone Priority Module (WHICH I HAVE) to allow the console audio to have takeover & priority on the repeat audio.

HOW do I wire the console in to the comparator/repeater setup? I see there are audio connections marked "CONSOLE" on the back of the comparator, but something doesn't seem right to me when I connect to them. There's a LOT of AGC on the line.

ALSO, IS it possible for me to have a 4-wire duplex connection from the repeater/comparator to the T1600 console so that I can still have receive audio while transmitting on the console, yet the console has priority TX audio on the repeater?

Which slot does the Tone Priority Module go in, and how do I configure all of this? I guess you could say I need the "Standard Public Safety Dispatch" configuration.

FWIW this is an amateur radio setup, not anything "mission critial", but I would like it to work to spec and as Motorola designed it.

Can anyone help?

Thanks in advance!

The comparator needs a tone keying module so it can key the station when any receiver has incoming activity. The console also needs to be tone so it can key the transmitter. So far quite simple. Now, who decides which tone encoder is used when the voter is already keyed and the console wants to talk? That's the tone priority module.

If the voter is up, TPM detects the tone from the console and filters it out, but uses the keying tone detector to keep the voter keyed up even if the inbound receiver drops. Console audio - 2175 Hz is sent to the transmitter. Jumper options allow either mixed receive + console or console only in that condition.

Complete wiring pictorials are in the installation section of the Spectra-TAC Comparator chassis manual 68-81039E50.

Level setting is a critical process that is also outlined in the manual. Be sure you use the -13 dB guard tone setting process for BOTH the receivers and the comparator itself. Heavy audio compression is a sure sign that levels are incorrectly set.

Yes, you can have duplex audio at the console over a 4-wire connection.

I would giver you the exact module location but somebody "borrowed" my manual a few months ago and it has not wandered back onto the bookshelf yet.


One more note - the SpectraTAC stuff is NOT digital capable, so don't try to run SecureNet coded audio through the voter - it will not go, period.

I would recommed getting a copy of the service manual, /\/\ part #6881039E50. It is acutally one of there "good" manuals. You'll probably want to tweat the system at some point anyway.

Having said that, pins 20&21 on the back of the Command Module are the Voted RX out to the wireline, it has screw terminals labeled "MON AUD". With the Tone Pri Mod installed, pins 19&20 on the back of it are console TX input. They also have screw terminals.

Good luck!

SZ