billyz
Super Member
Ive been messing with a Sansui qrx 3500 for a while . I picked it up for $50 along with a sansui sr2050 $50 also.
First thing I did was deoxit and faderlube as many of the switches and pots as I could. Measured the DC offset and adjusted them to 5mv or less each.
Not exactly knowing what the bias should be I referred to the qrx 5500 manual and set them to 25ma or a little less after warm up.
A few lamps were out and I just fixed the 2/4 light with a grain of wheat 6.3v bulb. Got all the others working or replaced.
I noticed recently the left rear was not coming on until I ran the volume control up a bit , then it would stay.
I checked the headphones and the rear was working fine, but plugging in the headphones would activate the relay and the same thing , no left rear.
So , I popped the plastic cover off the relay and ran some 600 grit sand paper soaked in deoxit thru both sides of the gold plated contacts.
Wha LA, the rear comes on first thing now.
Dont know if I caused long term damage to the contacts but, what the hey. Worse case ill need a new relay.
This little ( ha ha) qrx sounds really great with the Sansui SP200's front and SP 2500's rear.
Now, if I could just get the FM stereo light to come on. It has continuity thru the bulb. Maybe I need more than a simple T antennae. The FM sounds great though and It appears to be stereo and the quad synth surround does it's job to the signal as well.
Im hunting for a good QRX7001 or maybe qrx8001, 9001. I hear they really do the quad synth surround with better separation. Actually , I find the qrx3500 does a nice job, I can hear the separation and sometimes its really good.
First thing I did was deoxit and faderlube as many of the switches and pots as I could. Measured the DC offset and adjusted them to 5mv or less each.
Not exactly knowing what the bias should be I referred to the qrx 5500 manual and set them to 25ma or a little less after warm up.
A few lamps were out and I just fixed the 2/4 light with a grain of wheat 6.3v bulb. Got all the others working or replaced.
I noticed recently the left rear was not coming on until I ran the volume control up a bit , then it would stay.
I checked the headphones and the rear was working fine, but plugging in the headphones would activate the relay and the same thing , no left rear.
So , I popped the plastic cover off the relay and ran some 600 grit sand paper soaked in deoxit thru both sides of the gold plated contacts.
Wha LA, the rear comes on first thing now.
Dont know if I caused long term damage to the contacts but, what the hey. Worse case ill need a new relay.
This little ( ha ha) qrx sounds really great with the Sansui SP200's front and SP 2500's rear.
Now, if I could just get the FM stereo light to come on. It has continuity thru the bulb. Maybe I need more than a simple T antennae. The FM sounds great though and It appears to be stereo and the quad synth surround does it's job to the signal as well.
Im hunting for a good QRX7001 or maybe qrx8001, 9001. I hear they really do the quad synth surround with better separation. Actually , I find the qrx3500 does a nice job, I can hear the separation and sometimes its really good.