Batboard

I need to find a cheap n easy power failure alarm for a VHF MTR2K. This repeater is not used for dispatch, but strictly for well site alarms (Zetron Sentry Voice alarms). I know, upon power failure, that the unit sends a beep over transmission when it is keyed up, but the problem is they don't ever talk on the repeater, and obviously when there is a site alarm going over the air, you cannot discern the MTR2K beep from the Zetron alarm tones. I need a simple single input device that could key up and send a short burst every 15-30 minutes or so. The obvious answer is get another Zetron just for this function but we were hoping to find a cheaper solution if possible. Any ideas?

Are all the inputs used up in the SentriVoice unit? If not, the simplest approach would be to use that. As far as a loss of power sensor, there are commerical devices available. If you want cheap, find a wall transformer and hook it to a relay. When power fails, the relay will de-energize and give you a "loss of power" contact closure. If you don't have space on the Zetron, you could hook up a cheap external Base Station IDer that has a programmable time intervall. Set the call sign to something like all the letter "S" - all dots that would be easy to tell the difference from the real CWID. Look here: http://www.com-spec.com/id8.htm

Good luck!

SZ

Then of course you could add Moscad NFM.
Mine tells me everthing from when someone goes on site right down to the oil pressure in the generator when it's running.

Zaputil wrote:Are all the inputs used up in the SentriVoice unit? If not, the simplest approach would be to use that. As far as a loss of power sensor, there are commerical devices available. If you want cheap, find a wall transformer and hook it to a relay. When power fails, the relay will de-energize and give you a "loss of power" contact closure. If you don't have space on the Zetron, you could hook up a cheap external Base Station IDer that has a programmable time intervall. Set the call sign to something like all the letter "S" - all dots that would be easy to tell the difference from the real CWID. Look here: http://www.com-spec.com/id8.htm

Good luck!

SZ

I didn't explain it well. There are currently no Zetrons at the repeater site. They are at remote well sites out in the field. They report through the repeater to an answering service. I'm looking for an alarm for the repeater itself. Basically what I need is a one input Zetron.

EDIT- just saw the link you provided. That little IDer might do the trick. Thanks.

I know in the MSF's you can set them up so that if there's a problem wiht the radio it will send out periodic short tones which if you listen to them will signify that there is a problem. If your using a battery revert option (I'm not sure if these exist on the MTR's or not, it may have something like this built in.

Test it out and let it fail over and see what happens.

-Alex

alex wrote:I know in the MSF's you can set them up so that if there's a problem wiht the radio it will send out periodic short tones which if you listen to them will signify that there is a problem. If your using a battery revert option (I'm not sure if these exist on the MTR's or not, it may have something like this built in.

Test it out and let it fail over and see what happens.

-Alex

From my original post-

"I know, upon power failure, that the unit sends a beep over transmission when it is keyed up, but the problem is they don't ever talk on the repeater, and obviously when there is a site alarm going over the air, you cannot discern the MTR2K beep from the Zetron alarm tones".

The MTR does have a power failure alert, but it does not send until someone keys the repeater. As they do not dispatch over the repeater, it will not send until one of the field alarms transmits. When that happens, the answering service cannot discern between the beeps of the field alarm and the beeps of the repeater.

I suspect there are all sorts of neater solutions, but if your MTR has the Aux I/O board, you could always pin a wildcard input to the output of a utility power sensing relay, and then program the radio on the wildcard going active to change channel (same freq but different PL) and key up for 2 minutes. Have a receiver downstream on the freq and this PL, and when that receiver breaks squelch, you have a power failure at the site.

I remembered another cheap IDer: http://www.racominc.com/700.htm

Or you could get a little more fancy with an actual recorded alarm message with a digital voice announcer: http://www.racominc.com/900s.htm

Good luck!

SZ