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Multiplex Tuner Repair

Hi Folks,

As most of you remember, I was having trouble with distortion in my Scott multiplex stereo tuner. In mono it's good but while music plays in stereo, there's a good deal of distortion. I took it to a local technician but they had it running through a $10.00 receiver and speaker system. I mentioned to the tech that the problem was most noticeable with classical musical (honest) but they balked and said they didn't find a problem. By the way, after I paid the bench fee, I again mentioned a Scott Multiplex Charger and their two technicians said they never heard of that.

So now I'm at home with the 350 tuner and experiencing the same issues. I live in Cincinnati so I'm wondering whether or not someone near enough to me could fix this tuner the right way?

Also a proper FM antenna might help as I have changed stations and it becomes a little more listenable. I could purchase a Magnum Dynalab ST 2 and bracket it to the brick facade of my apartment building but I don't know how to ground it to the inside of my flat. As mentioned previously, mono sounds great and my thought is that it is getting enough reception in mono but not so much for stereo? At this point I'm frustrated and disappointed in the technician that I took it to.
goofyfoot
rar1's avatar
rar1
1,766 posts
 
Two questions:

1) in your apartment building, are the window and door frames made of metal, as these frames are often regulated to be in most major cities? If such is the case, no indoor antenna will ever bring in the stations in stereo halfway decently. Sorry ... that's the physics of it. It may also be that the classical station does not broadcast at a particularly high wattage.

2) what are you presently using as an antenna?

Rich
goofyfoot OP
1,356 posts
 
Hi Rich,
I've got threads going on about basically the same thing so thank you for being patient. Yes, Ive got metal window frames in this building as it was built in the 1960's. The station wattage shouldn't be too much of a problem, currently I'm listening to a weaker station that's further away and it's clear in mono. The tuning meter gets buried to the right when I have the classical music station on and mono sounds beautiful but stereo is a nightmare.
If the fm tuning is slightly out of alignment as well as the multiplex, could this explain an inconsistency between stations? My other thought is that classical recordings can be very delicate with a good deal of open space surrounding the instruments which could be the reason why the problem becomes more noticeable.
What it comes down to is that this is my first tube engineered component and so I'm learning a lot in a very short period of time. I'm enamored with the tube sound so far, I have it fed into an ASR Emitter II Exclusive. What's frustrating is that I replaced the 4 multiplex tubes with all Telefunkens and 2 of them are military grade so I'm impatient.
goofyfoot OP
1,356 posts
 
Sorry Rich I forgot to mention that I've got a single Monster 12 gauge copper wire on the 300 ohm antenna screw and that's connected to the thinnest wire of a TERK Edge without a power connection. No ground, I take it out of the window sill if I anticipate a storm.
Thanks!
rar1's avatar
rar1
1,766 posts
 
What I suspected ... metal window frames. In three words ... lots of luck.

You need an outdoor antenna ... window sill placement can be iffy, roof placement would be ideal. Can not imagine your building being ok with attaching anything to the facade, that is usually a municipal violation, as facade attachments are associated with falling bricks.

If I include the years working with my dad in his TV repair shop that had tin ceilings, no less, then this has been my experience for the past 50 years. I have given up on using receivers, all together.

Will your building allow you to place an antenna on the roof? Does the local cable company provide antenna hook-up?

On the plus side, you have good mono reception.

Rich
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