Nick's TX-20 and Pagers

[Shackle]

My TX-20 is nothing special, apart from that I was able to remove it from where it spent it's working life when the business downsized.

I've given it a good clean, and solved a couple of little issues (like the ribbon not advancing due to the motor being stuck).

I've also taken a raspberry pi and connected it to the line and bell relay terminals of the TX-20, and written a small program. Now through RPITX whenever I am in paging range (at home) I will get a notification when someone calls the machine or rings the bell.

Old technology is at it's best when you can find a use for it!

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[Shackle]

Hi Nick,

Brilliant Idea!

Kind regards
Michael

Gesendet von meinem 2109119DG mit Tapatalk

[DF3OE]

Cool idea.
What system and frequency do you use? POCSAG?
Would be interesting to get some more detailed information.

[Shackle]

Yeah, POCSAG with rptix.

I use NodeRed to handle the flow. I use an input node to monitor the state of the relay, then calls a function when that state changes. That function runs the pocsag script: var command = 'echo "0380717:' + incomingMessage + ' AT:' + timeFormatted + '" | sudo /home/pi/rpitx/pocsag -f 148037500 -r 512' "

Telecom Australia pagers used VHF, 146-149 MHz, but I have used a Metromedia pager on 454.175MHz with Rptix with good success too.

The antenna is only a small coil of wire on GPIO 18 (Pin 12).