Source for QSI 5022 CD-4 demodulator I C

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tcdriver

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I have a CD-4 demodulator with a bad QSI 5022 demodulator integrated circuit. Is there a known source for these I. C.'s? Thank you for your help.

Sincerely yours,

tcdriver
 
I will see what I can find out. Is that the only number on the chip? If not, what are the other ones? What kind of demodulator is it from? Who made the chip? If it is one of those big chips like they used in the technics demods, they may still be available through ECG Sylvania who (last time I checked) still lists them. But it may not be the same chip. I think they got stuck with a bunch of them. There is another small PLL chip that is used in a lot of demods and I believe it is still available. However, I am not familiar with that number.

The Quadfather
 
Thank you for your quick reply.

1) The only additional number on the I. C. is the 7448 date code. There is an "S" in front of the date code that would suggest to me that it may have been made by Signetics.
2) The CD-4 demodulator is a Southwest Technical Products Corp. unit built from a kit they sold back in the seventies. My kit was purchased in May 1976.
3) The I. C. is in a 28 lead dual inline package plastic.

A search on the internet led me to a Heathkit parts cross reference which would suggest that Heathkit used the same chip in one or more of their products. The Heathkit number is 442-605.

I will see what I can find out about the ECG part. Thanks for the tip.

Sincerely yours,

tcdirver


 
It sounds like the QSI Demodulator IC used in the Panasonic, Heathkit and other CD-4 Demodulators of that era.

QSI was the company founded by Discrete Quad Radio Inventor Louis Dorren that was later sold to Panasonic.


 
This chip crosses to ECG part number ECG813. Unfortunately a search on the ECG website came up "part not found". I wonder why they still have it in the catalog? I believe this is the chip used in the Technics SH400. Unless you can find a broken demod that has a good one, your chances are pretty slim. I suggest finding a JVC 4DD5 on Ebay or another demod with simple PLL chips that are still available. (the rest is discrete components except the preamp. For awhile you could get a good demod for around 20 bucks, I don't know what they go for now. Happy Hunting!

The Quadfather
 
The pin outs for the QSI 5022 appear to match the pin outs for the ECG813. The 5022 is, indeed, the chip(s) used in the Technics SH-400 and the Heathkit CD-4 board for the AN-2016 Modulus control/preamp. Lou Dorren was a chief designer of the chip.

Doug
 
The pin outs for the QSI 5022 appear to match the pin outs for the ECG813. The 5022 is, indeed, the chip(s) used in the Technics SH-400 and the Heathkit CD-4 board for the AN-2016 Modulus control/preamp. Lou Dorren was the chief designer of the chip.

Doug

True.

QSI - Quadracast Systems Inc - was the name of Dorren's company formed to explore 4 Channel Discrete FM Broadcasts. Later purchased by Panasonic/Technics.
He designed the Heathkit CD-4 Demodulator and was involved with Panasonic/Technics on the SH-400, both which use the QSI 5022 chips.

Dorren said the Heathkit CD-4 Demodulator was optimized for the QSI 5022 chip and has a magnitude of order improved frequency response vs. the SH-400.
As I remember it, the Heathkit CD-4 Demodulator had a lot of excellent detail on CD-4 playback.
 
I have a CD-4 demodulator with a bad QSI 5022 demodulator integrated circuit. Is there a known source for these I. C.'s? Thank you for your help.

Sincerely yours,

tcdriver
I have a CD-4 demodulator with a bad QSI 5022 demodulator integrated circuit. Is there a known source for these I. C.'s? Thank you for your help.

Sincerely yours,

I just found 3 pieces of the QSI 5022 chips that I received from Lou Dorren back around 1973, while looking for some TI IC's to sell from my large stock. Most of the 5022's I had were sold after my leaving Panasonic as their CD-4 Specialist. Since no sales are allowed on this forum I will be back to eBay.
 
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Hello BobZ I'm not sure about this: are you saying you have a few of the latest chip? It sure looks like there may be some later ones better than an earlier version? Thanks! Bill
 
Don't members offer items for sale on the forum quite frequently? Certainly I have bought items offered for sale here. "Since no sales are allowed on this forum " .... It seems BobZ has fallen prey to a misconception or misinformation.
 
Well I never heard of a newer version of the QSI 5022 since Lou released the final update around 1974. The 3 pcs. I have may have come from a friends estate as I remember giving him some for his use. and a circuit board but he never built a unit. Left me a lot of his electronics parts etc. I Gave a lot of devices, Boards, filters and literature to almost every audio houses that had an interest in CD-4 Quad in the country.
 
Now I'm wishing I could find (if I still have them) my letters to/from RCA back in the day. Some discs were great, others stunk, technical quality wise. I don't know about you, but I figured out you needed the best sound you could get from a quality stereo pressing BEFORE worrying about how your setup worked with CD-4. In other words, if a strain gauge cartridge sounded like metallic crap on a quality stereo pressing, it was not going to be optmum for CD-4. Ditto other cartridges. In fact, that damnable cartridge opened my eyes to the resonance problem of the cantalever assembly. Which you normally took care of (when using a moving magnet) by resonating the coil impedence with a several pf capacitor. All of which RCA called hogwash. I knew right then that it was headed for failure among the golden ear boys. Ah, for the fun times in downtown Chicago. And the tour of the ''sound rooms''.
 
Now I'm wishing I could find (if I still have them) my letters to/from RCA back in the day. Some discs were great, others stunk, technical quality wise. I don't know about you, but I figured out you needed the best sound you could get from a quality stereo pressing BEFORE worrying about how your setup worked with CD-4. In other words, if a strain gauge cartridge sounded like metallic crap on a quality stereo pressing, it was not going to be optmum for CD-4. Ditto other cartridges. In fact, that damnable cartridge opened my eyes to the resonance problem of the cantalever assembly. Which you normally took care of (when using a moving magnet) by resonating the coil impedence with a several pf capacitor. All of which RCA called hogwash. I knew right then that it was headed for failure among the golden ear boys. Ah, for the fun times in downtown Chicago. And the tour of the ''sound rooms''.
 
Yes I was there on the last one before it fell apart. The IEEE Radio and TV Consumer conference was also great in Atlington Hights at that time.
Well I never heard of a newer version of the QSI 5022 since Lou released the final update around 1974. The 3 pcs. I have may have come from a friends estate as I remember giving him some for his use. and a circuit board but he never built a unit. Left me a lot of his electronics parts etc. I Gave a lot of devices, Boards, filters and literature to almost every audio houses that had an interest in CD-4 Quad in the country.
Forgot I still have 2 more QSI 5022 in my Lou Dorren Demo CD-4 Decoder set in sockets but I will be selling the unit on eBay soon.
.
 
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