Batboard

When the place you work for, puts peoples lives on the lines each and every minute of the day just cause they are too lazy and want to wait for equipment to fail, which may cost lives, and just replace it with "new" digital stuff, as quoted by the higher ups, man that makes me mad. I've showed a major interest in our VHF radio system consisting of a 250 watt micor and a full complement of spectra tac receivers all across the county. And in just showing an interest, it nearly got me fired when I said I'd be willing to help out if needed due to a long delay in repairs to our aging system. All ended up being the one guy note "one" guy, great if he dies since he's the only one who knows it all, that has been put in charge of the radios, felt he was threatened by me offering to help him if he needed it. No words can do here.

Anyways, here's the question:

What happens when you put three fully loaded Spectra Tac comparators all into one zetron console interface? Which one picks the signal out of the three? I've been diggin through my comparator install and service manual and can't quite find the section that would describe how to mate three comparators and still get even voting across the 21 cards.

We have been listening to some annoying audio at work and before I was banned from the electronics room because I knew what a batwing is, I never saw any crossover jumpers hooked up for trio operation. From the service manual and pics, the comparators are each voting and feeding three different audio results to the console. WTF. This results in the first 15-20 sec's of each received transmisson being lost as each one of the three, votes and sends audio.
I can't probably change this at work, I need the job for the experience to put on the ole resume, but would like to figure this out as I own two full comparators and might someday like to intergrate both into one operation.

Rule #1, read the manual.

Comparator installation section 5.2.5 "Multiple chassis connections for 8 to 24 inputs"

Rule #2, If your not happy at your job, nothing else matters. Maybe it's time for a change.

Usually the top comparator that has the keying module in it is the one which handles the voting. The other chassis'es (sp) merely are homes for the other voting channels.

That's a huge system... I take it you're not in a very mountainous region...

"Usually the top comparator is the one that has the keying module in it "

There should be only ONE line driver or audio output line going to the console.

The SpectraTac receivers, power supplies and line driver cards are easy to fix.

I even have a few good ones laying around here.
(I do NOT have any comparitor parts)

My two bits worth:
Perhaps the most frurstrating part of any system is the CUSTOMER.
In almost 40 years of servicing 2 way radio systems the most frustrating
part is a customer that has absolutely no techinical knowledge, but does not let that interfere with management of their system.
Perhaps the repairman is his cousin, or what ever.
I could tell stories for hours about my experiences.

A bit of advice:
Be very careful what you ask for: You may well get it.
Do not attempt to modify anything unless you know EXACTLY how it works at present, how it is wired and why.
There is a reason for everything.
Perhaps some one wired it up with out consulting the manual. Perhaps there is a reason why it is this way.

Spectra-Tac is a reliable system, but for proper operation the levels are very critical.

If I was called on to optimize this system the first thing I would do is to verify the existing system block and level diagrams.

The next thing would be to review the system to see if it makes sense, and if any errors in the construction exist.

This often happens to systems installed by Motorola, and subsequently modified by whom ever had the low bid.

Do a thorough PMI. Verify all levels.

Test and monitor system to see if it works as expected, and find out what problems exist if it dosn't.

In the old days this is what we did in Motorola National Service.

No, I'm taking no action in this because I need to keep this job I have now, for the experience, so as I can move on, and soon. Thanks for the technical side input, I've found the section in the manual, spoken earlier, and have revised myself on what connections to make between the two of my comparators.
For work, we are just going to have to wait for it to crash so syntonics, or whoever is now working on it now, can come out and scratch heads alittle longer, and still not correct the problem. It does add to the twist when you have approx. half of the sites running leased lines and the other half running leased / microwave setups per site.

As always thanks on the input

CHART