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QRX disassembly quandary

bobforapples

bobforapples

Angular banjos sound good
I'm having a hard time removing or even shifting these two boards on my QRX-9001. The pass throughs need to be re-flowed and pinned, and I'm also going to recap the entire receiver.

I can't seem to figure this one out.... Maybe remove the faceplate? -but that would require removing everything attached to it (which is a bunch of stuff).

Normally I would just recap and pin with the board in place, but because I can't get to the bottom of either board, I'm stuck.

The boards are for the QRX and Dolby
Can anyone offer some advise?

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Bob,

Wish I could help you. I plan to go through a 9001 this winter. Have to get one first :banana:

On the 7001, almost everything plugs into an edge connector or has a plug to pull so the board can be removed. Only the tone amp/control board (wired to the mid level filter board), and the base power supply boards are hardwired (the later completely to the chassis).

There are at least three current 9001 mechanics on this site that I know of-(Transfmr, Robisme, Duffinator).
 
Well Bob may have a different answer, but here is Rob's.

You must tear down the front of the receiver. Yes, remove the tuning string. If you tape it up, it is pretty easy to put back.

It is a pretty big project. At least the first time it is.

Good luck.

Rob
 
Now I'm commited

I took Rob's advice....

I counted 203 caps to replace:eek:. (this includes every single electrolytic)

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Ah yes, i remember tearing mine down for the recap and the pass-thru service. No easy task. Great if you have absolutely nothing to do and you're snowed in for two weeks! :D

I've done full restorations on a dozen or so of these machines. Its boring, tedious work but the outcome is pretty kickass.
 
Nice. You will feel a great sense of accomplishment once you have it back together and singing again.

Take notes and label (I see you have).

Rob
 
All in good fun! I'm sure he will finish with flying colors and have her singing like a bird! Right Bobbo?

Keep at it!:D:D:D
 
Somewhere there is a thread regarding the recap of a 9001 that includes the first meeting of Quad Bob and Echowars. They got into a pretty heated debate (Imaging that with these two :D) over the number of electrolytics in a 9001. If I'm not mistaken the number is closer to 250 than 200.

- Pete
 
LBPete said:
Somewhere there is a thread regarding the recap of a 9001 that includes the first meeting of Quad Bob and Echowars. They got into a pretty heated debate (Imaging that with these two :D) over the number of electrolytics in a 9001. If I'm not mistaken the number is closer to 250 than 200.

- Pete
Click to expand...

Shoot, I think my new count is 235... I wonder what I'm missing.:scratch2:
 
bobforapples said:
Shoot, I think my new count is 235... I wonder what I'm missing.:scratch2:
Click to expand...

Your count should be 244 including the 4 main caps.

Off the top of my head.....here's what you may have missed:

There are 5 16v 10uf caps across the RCA jacks along the backpanel (they serve as shunts to ground for overload).

And, there are 5 more hidden underneath those sub pcbs on the main decoder/switch pcb. 2 are underneath the small switch pcb. Then there are two more "upside" down mounted to the sub pcb with the decoder switches. And, a 10uf low noise cap on the main pcb itself tucked underneath there.

You can access them once you desolder and separate those sub pcbs....which you have to do anyway to get at all the pass-through joints!!
You'll have a good time desoldering all those switch connections!:smoke: But, there isn't any other way. Enjoy!

62 QRX-9001's restored......and counting!!:smoke:

QB
 
LBPete said:
Somewhere there is a thread regarding the recap of a 9001 that includes the first meeting of Quad Bob and Echowars. They got into a pretty heated debate (Imaging that with these two :D) over the number of electrolytics in a 9001. If I'm not mistaken the number is closer to 250 than 200.

- Pete
Click to expand...

Ah.....yes! The good old days! :D

Back when Glenn was just a young whipper snapper cutting his teeth on anything he could get into his mouth....Kenwoods, Sansui, etc!!:nono:

But, he's all grown up now and knows his stuff!!:yes:

I still contend the QRX-9001 is the most complicated audio receiver made during the '70s. The Marantz 4400 comes close, but it doesn't have the "built-in" matrix decoders and CD-4 demodulator of the QRX-9001, and electronically speaking the 4400's o'scope is simple!

QB
 
QuadBob said:
62 QRX-9001's restored......and counting!!:smoke:
Click to expand...

I'm with Rob on this one, 1 is more than enough for me:yes:

I just ordered my caps, all Panasonic FC or FM series. A few of the 16v and 10v were bumped up to 25v or 35v. Aside from that, I found all the values I needed.

Bob,
What do you replace the 4 main filters with?
 
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