Sansui QRX-7001 Resistor Replacement

[OldNewFan]

Hi, Does anyone have a schematic for the tone board of the Sansui 7001?

I am looking for the value of the resistor for location R601, it was burned so the colors were gone.


Thanks very much.

 

[QuadBob]

It would help if you would include the board number you are referring to; such as F-2087 or F-2088 or ?

And, no problem helping out.........but it's good etiquette around here to fill out your profile completely, especially if you're looking for help and advice.

QB

 

[OldNewFan]

Hi QuadBob,

Thanks for your response. I do not know what the board number is (it's presently at the shop) All I know is that it is the tone board, with all the control knobs attached from a Sansui QRX 7001 manufactured in April 1976. If that is insufficient info I will have to get at the board.

I had filled out my personal profile but it was blank when I checked it just now. I have filled it out again. I have been a Sansui owner since 1968 but am brand new to Quad. I have decided on the 7001 from Sansui after reading many of yours and Hooded Crows input on these wonderful machines and am looking forward to getting my system sounding as good as I can afford.
Thanks much for your help!

 

[QuadBob]

Hi QuadBob,

Thanks for your response. I do not know what the board number is (it's presently at the shop) All I know is that it is the tone board, with all the control knobs attached from a Sansui QRX 7001 manufactured in April 1976. If that is insufficient info I will have to get at the board.

I had filled out my personal profile but it was blank when I checked it just now. I have filled it out again. I have been a Sansui owner since 1968 but am brand new to Quad. I have decided on the 7001 from Sansui after reading many of yours and Hooded Crows input on these wonderful machines and am looking forward to getting my system sounding as good as I can afford.
Thanks much for your help!

If it is in fact the Tone Control PCB Sansui F-2425, then the value of R-601 is 330ohms 1/4 W. I would warn you however that there are "other" R-601s in the QRX-7001.......most notably on either F-2087/2088 (off the top of my head)....so I would highly recommend that you confirm the pcb before applying the above info.

Secondly, I would be more than a little suspicious of anyone attempting to repair/troubleshoot a QRX-7001 without the schematic and service literature! If your local shop had the manual.........the info is easily found. If not..........you're just wasting time and $$ and the results will be questionable at best. Good luck,

QB

 

[OldNewFan]

Thanks again QuadBob!

Yes it was definitely the tone control board as I was there when they dicovered the burned resistor after replacing a bunch of 6 volt caps plus an assortment of others that had gone bad. I tried to order the 7001 service manual from eBay, which was available a few weeks ago, but I could not find it now.

I appreciate your concern which makes good sense but I know these people (austinstereo.com) and they are really excellent and some of the most knowledgable folks in town. Advanced degrees in EE, uber geeks, audiophiles and 25 years of experience fixing and rebuilding all thing vintage stereo and guitar tube amps. They love the Sansuis also and bring them back to original specs rather than substituting "superior" parts as experience has shown them that this does not necessarily give better sound. They did recommend that I get the service manual but mainly just needed to know what the manual said about that R601 value as the resistor was burned badly enough to not be sure about the color bands.
Thanks again Bob. Someday I would like to send you a 9001 for your famous super treatment.
Best Regards

 

[OldNewFan]

Thank you QuadBob,
It was indeed the F2425 board and the QRX 7001 is up and running with the installation of the resistor value that you mentioned.
In the meantime I have found and ordered the service manual on eBay for the 7001 so that we can go through the rest of the machine properly as you recommended. Thanks again for your help, much appreciated.