MX110 Inductor/Transformers Help Needed

Perkinsman

"I've never met a fixer that I couldn't break"
Is there a general order to adjust these for best radio reception? I tried adjusting one
& it seemed very tight. Are they easy to break? If one is broke, how could I tell? Lastly, how do I find replacements?
 
There are no replacements, and yes they can be broken.

The service manual will give the allighnment procedure a tech will use once the correct test equipment is available.

They should not be messed with.
 
...but how can I tell whether they are all working? Am I understanding you to say that if there are no replacements and one is broken, I'll have to toss the unit?
 
A factory replacement I/F transformer is not longer available after some 50 years from production. This doesn't mean they are not repairable, however. There are threads here at AK where their restoration is discussed. Restoration be tedious and patience will be required of the restorer, too.

For this reason, you should take great pains to ensure that the ferrite cores used in them remain intact. Without proper tools and techniques, at this age, they need to be gingerly dealt with. If the FM tuner section is working now, it is best to leave it be. That is, do not attempt to replace the tuner's tubes or even to move them to other positions - especially the I/F section along the right hand side. This guaranteed to mess up the alignment. The impact to you is that the tuner will not be as sensitive, may not operate reliably in FM Stereo mode and may have a distorted audio out in both stereo and mono settings.

If you can't tell they are working, it would be best to describe what it is that's leading you to believe it isn't working properly.

Cheers,

David
 
It won't tune in well or stay on a station long without drifting....lots of white noise and the station the dial says is inaccurate.
 
Take it to a qualified technician who is knowledgeable in tuner restoration and alignment. This is not something that can be performed by even the handiest of us as it requires an extensive electronics service background as well as specific measurement equipment.
 
Is there a general order to adjust these for best radio reception? I tried adjusting one
& it seemed very tight. Are they easy to break? If one is broke, how could I tell? Lastly, how do I find replacements?

Hello,

Which one do you suspect to be bad ?

I tried adjusting one & it seemed very tight. yes, this is normal ! the spring is strong and hold very tight the both half part of the transformer this is made for purpose to avoid any movement who will change your adjustment once it is done .

Are they easy to break ? Yes if you don't use plastic tools , yes !

If one is broke, how could I tell ? you will see it or the core will be loose

Lastly, how do I find replacements ? as mentioned before , no replacement is available at factory ( too old product) !

If you want to know my point of view : replacement is not necessary but repair is always possible except if you try to do it yourself and broke very thin wires ....
 
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Audio Classics rebuilds them. I had the FM discriminator rebuilt by them for my MX110. I think I paid $150 to have it done.
 
It won't tune in well or stay on a station long without drifting....lots of white noise and the station the dial says is inaccurate.

The good news: These symptoms do not indicate a problem with any of the Intermediate Transformers.

The bad news: If the tuner is drifting, then the local oscillator circuit is suspect.

- First thing to do is clean the pins on the 6AB4 tube.

- Do not try to move the tubes between the I/F cans along the right hand side. You should remove and clean the pins on all the tubes in the tuner section. DeOxit is your friend for this exercise.

- Next, you'll need to be sure that the power supply is able to deliver the +125 volts needed for the local oscillator circuit. If that voltage is off, likely there's a power supply problem elsewhere.

- If you're this far into the thing or don't understand why the last step must be completed properly, take it to a good tube bench tech or, better yet, a vintage Mac specialist.

Cheers,

David
 
Audio Classics rebuilds them. I had the FM discriminator rebuilt by them for my MX110. I think I paid $150 to have it done.

Yes , I know , I do it too but I have to precise that "rebuilt" is not the right word , because if it was the case it mean that you " rewind " every damaged coil wich is not possible ..." Refixed " will be better !

patend regarding these transformers is 1947 dated ......

I don't know many manufacturer keeping 1950 spares parts in stock today !

see my attached file of inside view ....Spring in the middle, top and bottom coils are in black , top and bottom cores are grey and mica capacitor in the bottom
 

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