Early MX 110 help needed

[hugo454]

after getting my MX110 back from a tech,I noticed a pop sound through the speaker shortly after turning it on.I thought that maybe there was a bad tube so I went ahead and replaced all the tubes in the MX110 after purchasing a tube set for this model from the bay. Now I have no F.M.! Phono section works fine
I am at my wits end and do not want to go back to the original tech because he has had another amp of mine for 6 months and I want this repaired quickly.
I am looking for someone in the South Florida area that could possibly help.
any suggestions would be appreciated.

 

[sberger]

If you can remember where the tuner tubes go that you took out, put them back in exactly as they were. Replacing them screwed up the tuner alignment. The only tubes that you want to play around with rolling, generally, are the preamp tubes(12AX7 & 6U8).

 

[hugo454]

I am not even sure which part is the FM section. I do see the tubes for the multiplex section.I have searched all over for a basic tube layout chart and cannot find one.Had to settle on finding a pic of the unit and trying to read the tube numbers off of the chasis since mine are worn away but that way is difficult to make out.

 

[hugo454]

I just wish I had a chart not a schematic

 

[sberger]

I know it's at least the 3 tubes on the right under the shields(looking from the front), and the MPX tubes. Perhaps your tech noted them when he worked on it? I'm sure somebody else here will be able to guide you.

I will say the fact that you're not getting any FM reception with the new tubes doesn't sound right. Even though the alignment was disturbed, you should still be able to hear something when you work the dial. I assume you checked the mute switch to make sure it's not on?

 

[hugo454]

I got it all to work, not sure how but now I have low output on the F.M but it works and phono is fine.

 

[psychoaudio]

I got it all to work, not sure how but now I have low output on the F.M but it works and phono is fine.

How? what did you do different?

 

[sberger]

Might need more cleaning? Did you fiddle with the tubes? Was the muting on?



Anyway, glad it's working for you. Now, lets see a picture. How early is it? What's the serial number?

 

[hugo454]

found a local guy that works from home,I quickly brought it to him and he began the process of checking the tubes and their respective positions, after a short while he was getting an FM signal but we were unsure as to exactly I had screwed up.I still have low output on FM,and the phono section plays fine and much louder.I think the tuner needs realignment after playing with the tubes.I will probably leave it with him when I go away on vacation to get it working 100%.it was not the muting however.

 

[clinic-audio]

Hello
This is not the first time that we read trouble with very old tuner (MR71 or MX110 Z or not )
Please don't forget that buying such units ("working unit" ) is a great risk because of the age and quality of ALL the IF transformers . They need to be "redone" ( I mean micas capacitors replaced) and there is no many guys able to do it (experienced) and if you see an MR71 or an MX110 at 600/800 $ should mean for you don't buy !!
a high quality tuner should cost around 1800/2000 $ because this job is done . It take a long time because it is a long and very carefull process . Don't even to think to do it yourself because you are not able to do it and you may broke very fragile wires and then, it is dead because replacement part do no more exist .
AUDIOCLASSICS (Richard Modafferi) TERRY DEWICK are the only tech that I know able to do it .
Think about that before it will be too late ..

 

[Pio1980]

The IF transformer thing puts me off tuners of this vintage without the full bench overhaul /alignment.