Electronics > RF, Microwave, Ham Radio

Mid 1970’s iambic keyer CMOS DIY design

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Kjo:
I built a keyer in ~1976 based on 9 4000 series ICs and a few capacitors and pots. 45 years later, I still have it and it works sort of. Dots work but dash no. It was built on a perf board with wire wrap. I will never figure it out with that construction. But I remember that several of us at Hughes Aircraft built this from plans in QST, or Radio Electronics or some other magazine of the early 1970’s.

I’m hoping there is someone out there who is as old as me and remembers this project. I’d like to fix this thing and use it. I know that there are many micro based designs that are better, but there is the nostalgia thing.

Kjo - KO3Y

Kjo:
I have looked for this in the past with no luck, but I now found a reference to a QRP Accu-keyer. This may be it!

mag_therm:
Here is one project
It is paywalled :  (Australia Trolley == USA Cart)
-----------------------------------------------------------------------------------
https://www.siliconchip.com.au/Shop/15

Electronics Australia article scan, March 1978 - Electronic Morse Code Keyer

Scan of the Electronic Morse Code Keyer article from Electronics Australia magazine, March 1978 issue.
7 pages, 11.3MB.
There is a copyright notice watermark on each page.

Cat No SC3080. Price: AUD $10.00 1    add     Add to trolley

floobydust:
73 Magazine CW Keycoder I  July 1976, improvements 1977 Aug. pg.159
Electronics Australia March 1978 oops it has paddles
edit: deleted url so not to spoil it

Kjo:
Thanks for the suggestions, but it was indeed based on the Accu-Keyer in QST August 1973. I evidently took liberal freedom back then to apply DeMorgans theorem. But I fixed it!
 QRP_Accu-Keyer.pdf (1004.72 kB - downloaded 100 times.)
 QST_Aug_1973_p19-23.pdf (989.43 kB - downloaded 98 times.)

Actually the TTL was from QST and the CMOS version I built was from Aug 1975 73 mag.
73 mag article has no detailed functional description, but the QST article does.
And K7MEM did a analysis that is quite good.
https://k7mem.com/Keyer_Accu-Keyer.html

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