WØIVJ's Telephone Remote Control Project
(Click on pictures to enlarge)
Email: w0ivj@arrl.net
My job requires that I travel, so in order to enjoy my amateur radio hobby, I constructed a telephone interface which enables me to run my ham station remotely.  Basically the interface allows me to dial my home phone number and connect my interface with a password after the answering machine answers.  The interface recognizes the password and takes the line away from the answering machine as if someone had picked up the phone.  I can then send tones to the interface which are converted into ascii commands which are sent to my TS-450S transceiver over an RS232 interface.  The transceiver responds in ascii over the same interface, and the responses are converted into short sentences and enunciated back over the phone line.  When the voice enunciator is active the microphone and audio from the transceiver are disconnected from the phone line.  Pictures A, through F show the construction, and G shows the schematic diagram.  The command structure is listed in the Command Structure Document, the enunciator vocabulary is listed in the Vocabulary Document, and the microprocessor code is listed in the Source Code Document.  The source code is for a NetMedia BasicX BX-24 chip which is a 24 pin chip that holds 8000 lines of Basic code and has floating point math.

A...B...C...D...E...F...G..Hi Res G

With phone cards being so cheap I can enjoy my hobby for an hour for a little over $2.00, which is cheaper than a movie and a lot more entertaining.  So far I have operated the station from four states and one foreign country.  I have used both land lines and cell phones.  My most unusual contact was from a cell phone while in a moving vehicle in Kiruna, Sweden which is above the arctic circle.