Discussion in 'Homebrew and Kit Projects' started by KF5JAK, Apr 12, 2012.
Anyone know of any "how-to's" on building a phone patch controller?
Not really sure what you are looking for. Phone patch has been greatly diminished and is not overly popular as it once was. Which means the older amateur radio publications will have more information in them. The following article was from Ham Radio October 1985; http://massis.lcs.mit.edu/archives/technical/phone.patches. Maybe this will help.
Are you looking for phone patch or repeater auto patch?
Phone Patch interfaces (Plain Old Telephone Service [POTS] to Radio) were common from post-WW2 to late 1970s.
Almost every manufacturer offered a soluton, with Heathkit HD-19 (1961) and later HD-15 being popular kits for older radios.
ARS Repeater Autopatches (1960-1990) and Cellular/Mobile Phones (1970s to Present) ended their widespread usage.
Are you really asking about a need for Repeater Control or Auto-Patch ???
Thanks for the links, and no Repeater Auto-Patch. Just regular ole' phone patch system. I could do it my self, but wanted to see what others have done. I was on 20m the other day and heard a gentleman in the Gulf of Mexico get a phone patch from a man in the UK back to the gentleman's wife(?) in the US. It was interesting, so I figured I could add that project to my list!
EDIT: I'm actually going to start working on a simple cell phone patching system as well, either using a scrapped bluetooth headset, or the mic/speaker jack on my cell phone (Sprint EVO 4G).
In the 1960s and early 1970s, when I started -- you would regularly hear phone patches on 20 meters (sometimes 15 or 10 if the band conditions were good) from Southeast Asia (Vietnam War era).
Senator Barry Goldwater was active in the practice. That was high point of phone-patch usage.
You still hear an occasional patch request on 14.300 MHz Maritime Net.
In my hometown, Ron Pheonix, a civil engineer/radio amateur handled phone-patches & traffic in our area to local families during Vietnam War. He was a good friend of Barry Goldwater (Barry's mother was from western IL) and Barry had cousins in our area.
DIY Build of Phone Patch
Many of same parts for computer Sound Card interfaces.
The main difference is telephone network interface -- old dial-up modem cards will have those parts!
Grab the Heathkit Phone Patch manuals -- everything you need to build one!
I wouldn't build a phone patch, when so many are available very cheaply second hand. Heathkit and lots of others made thousands and thousands of them in the 1960s and 1970s and they don't need any sort of "controller," they are simply VOX operated, so once you engage the patch, it's "hands free" operation.
I see them on the market all the time for about $25. I couldn't homebrew one for that. They include hybrid isolation transformers (to impedance match and prevent ground loops) and level adjustments for the rig and the telephone. Just plug them in and use them.
That's all "third party" traffic, and you are the control operator once it's engaged, so your responsibility is to make sure you ID every ten minutes and monitor the conversation to assure it's of a personal nature and doesn't include profanity, music or other things that are prohibited.