STAN/F1SLSApr 24

I ordered a bundle of ten 4.433619MHz xtals (for 1.2€).

Can you guess what they will be used for? 😉

Tip 1: it is related to #amateurRadio

Tip 2: it is related to an old very popular "thing" a lot of #ham (at least in Europe) owned in the 90's

#radio #hamradio #electronics

Show threadSebastian DO2SGFApr 24
@f1sls I think that is the colour carriers frequency/offset from the brightness carrier in the PAL system, right?
Show threadSTAN/F1SLSApr 24

@DO2SGF

Yep, it's this xtal, exactly... but in the 90's it was used to cadence a certain chip used on a certain PCB for... data transmission.

Tip for you : this thingy originates from your country and was very popular all over Europe in the ham community at the time...

Show threadScott VE3QBZApr 24
@f1sls @DO2SGF tnc?
Show threadSTAN/F1SLSApr 24

@ve3qbz @DO2SGF

Well, since it has no "intelligence" on board, it is considered as a simple modem/interface, the computer has to do the heavy lifting...

Show threadScott VE3QBZApr 24
@f1sls @DO2SGF I know what you are describing, I think (same circuit style can be used for RTTY tone discrimination I bet) but I wasn't a ham in the era when this would have roamed the earth
Show threadSTAN/F1SLSApr 24

@ve3qbz @DO2SGF

I see what you are thinking about (the "Hamcomm" modem), but it's not exactly that.

It's the famous (at its time) BayCom modem using a TCM3105 (and a very common 74HC04). It was designed for 1200 bauds packet and worked with some specific MS-DOS software when it came out.

It was designed in Germany and was a hit in Europe in the 90's.

Show threadScott VE3QBZ
@f1sls @DO2SGF oh that's very cool! Like a packet dongle!
Apr 24 at 12:36pmWeb
Show threadSTAN/F1SLSApr 24

@ve3qbz @DO2SGF

Yep! And the original version was even tinier than the home-made version!

https://www.youtube.com/watch?v=LmQlRecQBj4

Baycom - The Poor Man's Packet Radio Modem and Software (it's not)

YouTube