74HC943 vs 74HC942

[neazoi]

Hi, I want to find if there are any differences in these chips besides the split rail PSU.
I see that the table marked as "Table II Universal service order code resistor values" is different between the chips. I don't understand what it really means, can you help?
Does it mean that the 74HC942 is more sensitive? Or they just did not bother writing the extra table values on the 74HC943 (not updated)?

 

[KlausST]

Hi,

sorry I can´t answer your question.

Funny: One datasheet says "preliminary" in the year 1988. .
Are you sure they are available? .. and useful? There was some progress in the past 30 years.

Klaus

 

[neazoi]

Well I cannot find any other through-hole 300baud bell103 chip with so few peripheral components to make a complete modem. So if progress means more complexity, sorry...

 

[KlausST]

Hi,

I guess old used modems can be bought very cheap via ebay or so...

Klaus

 

[danadakk]

A possible approach, single chip -

https://www.cypress.com/file/134251/download

https://www.cypress.com/documentation/application-notes/an60594-psoc-3-and-psoc-5lp-low-frequency-fsk-modulation-and

Some minor mods need to be done to project to bring it up to date. Also
I would recommend it be done with PSOC 5LP rather than PSOC 3.


Regards, Dana.