Small stuff of interest.

[Doodski]

 

[Doodski]

 

[Doodski]

 

[Doodski]

 

[Arvind]

One of the only two personal Twin Cassette Recorders. Other one was Panasonic RX-HD10.

 

[Tks]

Wow I was just watching about the RCA video discs on Technology Connections channel (a 3 part series about the format and it's doom). What were the chances of that..

 

[Kal Rubinson]

 

[mhardy6647]

The captioning isn't quite right Stereo records are cut with both vertical & horizontal modulation, so the encoding of the two channels of data is a little more subtle than that!

This actually turned out to be very important in the early days of stereo. REAL mono cartridges have (had) essentially no vertical compliance, and will tear up a stereo record. Some (perhaps most?) of today's "mono" cartridges have both vertical and horizontal compliance and just mix the two channels together to output a mono signal.

It gets even weirder in the transitional years from mono to stereo LPs in the mass market (1960s). Some mono LPs were true mono (no vertical modulation), others were mono signals cut with a stereo cutterhead (both vertical and horizontal modulation). Like lots of things in the real world, things get complicated...
https://www.vinylrecorder.com/stereo.html
https://www.ortofon.com/hifi/cartridges-ranges/true-mono/

 

[Wes]

the guy with the surplus sem really needs a linear actuator to program for the record movement

 

[maverickronin]

Look at all those "steps"! It's worse than digital!