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The HH Scott 350 A MultiplexCircuitry

I've been listening some to my 350 Scott but only in mono. However my belief is that it's all stock so I'm hoping that replacing the tubes in the multiplex will clear up the noise and microphonic echo from the 6BL8. Yes, I'm getting loads of grumble and interference from the stereo selection.
An additional multiplex concern however is that the multiplex circuitry in the 350 was a compromise to the refined circuitry of the 310 E. I have procured (thanks to good Audiogon friends) the repair manuals of both the 310 E and the 350 as well as both schematics and I'm hoping/wondering if my local technician will be able to improve upon the 350 multiplex circuitry by comparing it with that of the 310 E? I was told by a friend that this is possible if I were to provide the technician with the repair manuals and schematics for both tuners but I'm still somewhat doubtful.
If anyone ( Al ? ) would shed some light on this and lend a suggestion/s for me to pass along to the technician, then I'd be very grateful. By the way, I have a Telefunken E80CF (6BL8) , A balanced pair of Telefunken 12AU7's and a Telefunken 12AT7, all Amplitrex tested on hold for payment. These I'll take with the tuner and hope that he orders the best capacitors. I want to go full force with this project to the best of my abilities.
Thanks To All!
goofyfoot

Showing 6 responses by atmasphere

atmasphere's avatar
atmasphere
11,577 posts
 
The big deal here is to make sure that the unit is properly aligned- for that you need an FM stereo generator- or your tech does.

If I recall right, that unit can beat if its out of alignment- that 'grumble' you mentioned.

If its not been done in a while, an alignment of the entire unit would not be a bad idea!
atmasphere's avatar
atmasphere
11,577 posts
 
I would try with Antique Radio Supply in Arizona- they have a pretty wide range of can-style multi-section filter caps.

I assume you are talking about rebuilding the power supply.

Otherwise replacement of other caps is not going to win you much unless they have drifted in value or have some obvious defect.
atmasphere's avatar
atmasphere
11,577 posts
 
Yes- it needs the multiplex section to be aligned. The shop will need a stereo multiplex generator to do the service.
atmasphere's avatar
atmasphere
11,577 posts
 
Did they perform a stereo multiplex alignment?
atmasphere's avatar
atmasphere
11,577 posts
 
Just FWIW, we can do a stereo alignment too. FM Stereo Multiplex generators are not as common nowadays as they used to be. So it does not surprise me that a newer shop might not have that instrument on hand.
atmasphere's avatar
atmasphere
11,577 posts
 
We are a manufacturer, and we do a lot of work in the service arena also. As a result, I try really hard not to get in trouble with the site rules.
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