Telephone Radio Patch

[Wire Fox]

I'm looking to make use of some older amateur radio tech... Once upon a time, before cell phones, I've heard (not really old enough to have used these) that telephone system patches were commonplace, allowing you to use an HF or VHF transceiver to communicate with another VHF/HF transceiver that's connected to a telephone landline. I'm going to be looking into amateur radio resources to figure out the telephone system patch portion, but I was wanting to add some autopatch capability to a PRC-104. To do this, I should just need to add DTMF. Does anybody know if the field phones can directly interface with the radios, or some sort of DTMF adapter might exist that can be hard-wired to the radio? I'm trying to avoid using something that would require me to have a microphone on the radio pick up open-air audio from a separate device, like on those old-school, pocket auto-dialers that you held up to the telephone receiver.

Just for reference, there's two major categories for this: patch and autopatch. Patch systems will have an operator receive the request and will manually dial the landline and then bridge the call to the radio. That operator can also manually switch between receive and transmit so that no VOX system is needed. An autopatch replaces the operator, allowing the radio requester to dial with DTMF. Switching between sending and receiving must be done with VOX, more DTMF signaling, or you will need to setup a full duplex connection to not need switching.

All-in-all, my rationale for this is just to extend my telephone range into more remote areas, without a big investment into a satellite phone. This could be useful for an emergency, or just nice for checking in with home on longer trips. ...because really, how neat would it be to be able to actually call home on a military HF rig?

 

[just me]

I use 2M for this. Where I live, I can always hit one. It helps that I have a good antenna and 60 watts

 

[Wire Fox]

I use 2M for this. Where I live, I can always hit one. It helps that I have a good antenna and 60 watts

Do you have something to adapt a DTMF panel on an older military radio, or are you just using an amateur radio with a built-in DTMF panel?

 

[just me]

I cheated and put a Yaesu 2600 inside a dead radio.

 

[Wire Fox]

I cheated and put a Yaesu 2600 inside a dead radio.

Nice.

Also as dumb luck has it, I have the main unit of a GRA-39 sitting in my closet. It's way overkill for my intended function-and I haven't done the research yet to see if it would even properly transmit the necessary tones to the radio-but it has all of the physical connections needed to physically patch a field phone (with its touch tone panel included) through to a radio. Before I tear into a manual for one, if I can find one, does anybody know if a GRA-39 can control a radio via field phone, or does it only DIRECTLY control a radio?