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[Reply #60 on:]

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[Reply #61 on:]

DM74LS138 3-to-8-line decoders or DM74LS139 2x 2-to-4-line decoders. 5.8Ghz Video transimiter: AWM683 module 5.8Ghz Video reciever:  AWM682 module

Wow, more stuff to look at...

I'm wondering about all the 74xxnnnn parts.. Maybe I'll look at putting a kit together with lotsa those.. Problem is just handling all those parts to collect in kits is a lot of work for very cheap parts. Hmmm..   any opinions??

I remember buying my first 7490 counter and 7447 7-segment display driver. in a set for about $10. Miraculous stuff. In 1969 anyway 

[Reply #62 on:]

DM74LS138 3-to-8-line decoders or DM74LS139 2x 2-to-4-line decoders. 5.8Ghz Video transimiter: AWM683 module 5.8Ghz Video reciever:  AWM682 module

Wow, more stuff to look at...

I'm wondering about all the 74xxnnnn parts.. Maybe I'll look at putting a kit together with lotsa those.. Problem is just handling all those parts to collect in kits is a lot of work for very cheap parts. Hmmm..   any opinions??

I remember buying my first 7490 counter and 7447 7-segment display driver. in a set for about $10. Miraculous stuff. In 1969 anyway 

Were there 7-segment displays before the 70's then?  I think that was the era of the first digital watches, outrageously expensive LED display ones with v. short battery life!

[Reply #63 on:]

I'm sure there were SOME 7-segment displays before 1970, but 'Neon' "Nixie" tubs with nicely formed numbers were most common.

The first digital clock I built for Broadcast stations in 1970 used the RCA "Numitron" which had filaments in a 9-pin vacuum tube envelope. They were driven by the SN7447s.  They looked like this:


Actually they looked better in a dark cabinet...

A friend and I made a few dozen displays with plastic segments embedded in dark "Bondo" type auto body filler. We made 2-foot long strips, and sawed about 24  sections off, polished the fronts a little, and embedded small incandescent bulbs in the back.  That was Broadcast Clock V2, followed by the Recording Timer, where you could see the running time from when you pushed "start" on the cartridge tape machine :-)

Digital Logic. Wow. I was very temporarily the State of the Art in my field. My FET stabilized crystal oscillator with schmitt-trigger output to digital was published in Electronics.

Boy, is that stuff obsolete    I'm trying to stay at least somewhere ON the obsolescence wave