Batboard

Hi,

I'm wondering if it is possible, and possibly inexpensive, to patch a radio into a school's PA system operated via telephone.

The PA system is used by dialing an access code on any telephone in the school. I'm looking for an inexpensive solution if possible.

Portables would would be low-end Motorolas (Motorola CP200 etc.).

Thanks!

It's possible, but I don't know how it's done. I've seen it done where you key up your portable on a certain channel and out comes your voice over the PA. I've actually used the PA that way at a large exposition venue, but I wasn't the one to set it up.

I'm sure someone else will chime in.

Your best bet for accurate information about this would be
the system manufacturer. RF interfaces are common these
days in digital systems and the question should not be a
difficult one for a properly trained systems engineer at the
factory level. It's being done in nurse call systems, for one
example, all the time now in the Rauland, Jeron, and similar
manufacturers' equipment, all of which are now digital and
have as part of their componentry a PA system.

Find the PA amplifier and take the audio out from the radio and plug it into one of the inputs, I'm sure there are plenty of extra inputs.
The only other equipment will be an audio transformer to match the impedences correctly. Simple to make, if it is a high school, just tell the physics teacher you want an impedence match from 4 or 8 ohms to whatevear the PA system needs and he or students will build it for you

I have a way you can do it rather inexpensively. You will need a SiteCAST module (http://www.criticalrf.com) on the radio and an extra telephone to "dial into" that has auto answer. You will also need to grab audio from the intercom system which should be a piece of cake since you already own that. Just put all three sources in one iP conference room and away you go.


Steve

At work, we have a Zetron 35A Microconnect connected to a Maxtrac. On our radios, we can hit a button and "raise" the patch, and we're seen as an extention on our PBX...pushing the 3 digit extension for our paging system allows us to page throughout the building.

I don't know if the 35A can be interfaced into a PA system or not, but that might be a decent solution.

http://www.zetron.com/data/site/templat ... radio/m35a

There's a PDF spec sheet on there.

How about setting up a single channel receiver in the building and running the audio into one of the P.A. amplifier's inputs?

Especially in a school... you dont want people accidentaly transmitting on the P.A . system and interrupting classes. Therefore, there sould not be a "single channel reciever" with you just keying the radio on a certain freq, this would enable security guards and anyone with a radio on your frequncy, able to transmit and go over the PA system..... A side note, could you imigane a kid getting hold of a radio and interrupting class and making fake announcements?.........

Or even any interference on that frequency to go over the PA system.

If the CP200 san do a DTMF encode, or any type of tone encode, it would be best to have the radio encode a tone, have a radio with that type of decoder open up the audio out of the radio into the PA for however long you deem necesssary and then the person that keyed the tone up can speak.

Connect Systems Inc Model 6800 radio-telephone remote interface unit. Have one NOS.

Bat2way wrote:Connect Systems Inc Model 6800 radio-telephone remote interface unit. Have one NOS.

PM sent. Thank you!

I've setup my High School's security repeater this way. The security advisors carry DTMF Visars, and so do the school admin. It's in the format of "*123" to bring up the patch, then dial any 4 digit office/room extension, or use the 4 digit School PA intercom code. It's all done thru the Zetron on the GR300.