(1974-12) SQ Stereo Enhancement [CBS Labs]

[par4ken]

I don't think much consumer electronics was produced in China in the 1970's.

Not China but the orient in general. The stocks could've easily made their way to China over the years! I'm sure China would've/could've been a dumping ground for such items!

 

[Soundfield]

Not China but the orient in general. The stocks could've easily made their way to China over the years! I'm sure China would've/could've been a dumping ground for such items!

Your faith in China as being a reliable source of genuine components is not universally shared.

 

[barfle]

Yes for the decoder/encoder I would suggest using the Fosgate circuit. It's six pole and all the parts are readily available, but I would recommend using a better op amp than the TL084. On the other hand the MC1312P and the after market ECG/NTE type replacements are also readily available.

The enhancement circuit should produce 90° phase shifts as that's what you need to simulate SQ encoding.

Are schematics available?

 

[par4ken]

Are schematics available?

Yes just flip back earlier in this thread!

(1974-12) SQ Stereo Enhancement [CBS Labs]

Here is a copy of the final version of my SQ Encoder... To use to synthesise SQ from stereo, only the front inputs are used. With the pot turned up a left input is encoded as a left back and right as right back, while center front stays upfront. , 270° enhancement. The other extreme produces...

www.quadraphonicquad.com

 

[MidiMagic]

I got everything from ECG replacement parts in the 1970s - two sets. But I never used them. I intended to build the decoder when I had time.

NTE took over the ECG line in the 1990s.