tough one - phone system - radio interface

[radioinstl]

Ok here goes, my Fire Chief asked if they was a way to do this, he had seen it done before. We have a repeater channel we are on. We have a motorola radio with a local deskset hooked to it. We also have a Partner ACS R7.0 phone system. he wants to know if there is a way to connect the radio to the phone system to talk back, we currently have the radio audio output piped in to the phone on the music on hold feature. it plays the radio audio on hold and also on the speaker on the front of the phone any time the phone is not being used. The had part i see, is how to get PTT from a phone desk set. (DTMF)? .He basicly want to be able to press a button on the phone (like you were dialing an extension) and be able to talk and hear on the radio channel. If any one has any experience or suggestions please let me know. We are willing to do needed add on (tone or dc remote, MRTI what ever gets the job done. Thanx. Scott

[Dan562]

Here's a couple of sites to interface a Touch Tone Telephone into a Base Station:

http://dvservices.com/download/C-550-RP ... remote.htm
OR
http://www.vega-signaling.com/index.htm

One item your Chief should understand is the FCC's view on Telephone Interconnects MRTI (Autopatch) in Urban enviroments. The commission does not favorly look upon Autopatch as a good neighbor/co-channel user policy because it ties up the RF channel in a metropolitain area. If you're located in a rural area 60 or more miles away from a major city then you can use Autopatch.

Using a standard Touch Tone telephone to connect to the Base Station is a different application.

Dan

[radioinstl]

Dan, maybe you dont understand, we dont want to patch the PSTN to the channel, we want to use the internal phone system we have as a large local remote you could say. you would not have any access to the PSTN from the radio channel and vice versa. On a phone you can dial, say "12" and it would connect you to extension "12" in the engine bay. Just as say, you press "20" and instead of an extension, it is the radio. Now we can do that no problem, press "20" and hear the radio audio, the question is how do i activate PTT from the phone?

[Dan562]

Ok, I understand what you're trying to accomplish. ZETRON has a Model 30 DTMF radio interface that I think will work for your application and it provides VOX for the reverse Telephone patch PTT operation. You can read more at the following website:

http://www.zetron.com/

I wouldn't hesitate calling their sales and applications engineers to answer any questions you may have on the product. Zetron is an excellent company to work with to solve your requests.

Dan

[spareparts]

We also have a Partner ACS R7.0 phone system. he wants to know if there is a way to connect the radio to the phone system to talk back

Scott,
I have installed a lot of AT&T/Lucent/Avaya stuff - Two things that may not be readily aparent:

The control box (KSU) for the ACS does not like stray RF. Using your ACS as a remote may introduce RF into the system. If yours acts up, PM me & I will dig out the comcode for the RF supression kit.

Make sure that you change the UPS batteries every 24 months, even if the UPS says they are OK. (if you don't have the phone system on a UPS, get one.)

Martin

[radioinstl]

Dan , thanx a lot. The model 30 from zetron will be perfect for our need. Martin, thanx for the input, we do not have our on an UPS, we have a full back power supply system for the station running off a natural gas feed auto switiching genarator.. Again, thanx for all the quick help. batlabs comes thru again. Scott

[spareparts]

Martin, thanx for the input, we do not have our on an UPS, we have a full back power supply system for the station running off a natural gas feed auto switiching genarator.

Scott,
Way to go! Since you already have a genset in place, the only thing you need to do is change the memory retention battery every 5 years.

The last ACS's producted have a supercap to hold memory programming during the couple of seconds without AC power (IE until the genset picks up the load)

Martin