Tivoli Model One radio tuner issue

If you look at the tuning capacitor in any older radio, you'll see that it consists of a bunch of interleaved plates, half of which are mounted on a shaft that rotates to let them mesh more or less. The more they are intermeshed, the higher the capacitance and the lower the tuned frequency. Taking a more careful look, you'll notice that the stationary plates are insulated from the frame of the capacitor while the rotatable plates are mounted directly on the shaft which is in contact with that frame. The electrical connection between the shaft and the frame is thru a ball bearing on one end and usually a brass spring on the other end. Both ends were lubricated at the factory, but, with time, that lubrication dries out and oxidation occurs. Metal oxides tend to be insulators. Once the contact between the shaft and the frame, where the radio makes its connection, becomes unreliable or intermittent, you'll stop getting reception or there will be a lot of noise as the shaft is turned.

Moving the shaft back and forth can break thru those insulating films. You can try Deoxit to remove the oxides and follow up with Shield to provide some longer term conductivity. I like to also add a bit of high quality corrosion preventive grease at the same time, for the longest term benefit.

Thank you for the details. Interesting. Will try.

If it's one of those open frame tuners, have at it. If it's one of those clear plastic super compact square tuners with plastic film separating the plates, then any cleaner you use that carries a lube that doesn't evaporate will detune the tuner. It will work, but it will cause your dial to be off, sometimes quite a bit. Over time, the error will slowly decrease but never go away. If the radio has an osc trimmer, you might be able to fudge a lot of the error away.

To be honest I have no idea. Maybe the video I linked in my original question will tell you. Won’t have access to the device until next time I visit my parents and this may take a while unfortunate.

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** See:

...... Phil

Auto lock-in, analog tuner. Interesting but doesn’t tell me much. Should not be the plastic kind mentioned by ohg…because is not super compact. Next time I will try cleaning and lubing.

For now tried to salvage at least the speaker function utilizing the auxiliary port for streaming from an iPad. Unfortunately my parents never understood how to use it.

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** Fraid it is one of the "super compact' kind, open frame ones are much bigger. ** Note ohg's advice.

FYI it is common for open frame gangs to become noisy when moved but rare with the compact examples.

....... Phil

From my original post:

With the compact kind we should obtain detuning if lube does not evaporate completely (@ohg). Also because is auto lock-in substantial wiggle is built-in already. As demonstrated in the video linked by you.

I remember tune-in always has been a bit odd with Model One. But video in my original post shows tuning in vastly improved after cleansing. Or so I assume since you mentioned background noise should not be an issue with compact tuners.

Streaming to it I believed to be the definitive answer to this kind of issue. Unfortunately reality hit me.

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** See: I had one customer who decided to use spray lube ( WD40)) all over the open tuning gang of his FM tuner. De-tuned the band so much only one station was left on the dial, way down the bottom end.

..... Phil

Wow that was unexpected. I now realize how big open frame tuners are. Also very interesting to see how they are made.

Clearly Tivoli One has a compact one. Also as you mentioned compact rarely become noisy when moved. I remember my parents picking up not much else than noise but am not sure if from the tuner being noisy itself or just incapable of tuning in. Will see what I can do. Just refining the streaming solution perhaps.