tuner has "noisy" tuning at bottom end of FM dial

I have a Kenwood KT815 tuner - pretty decent 5 gang tuner... At the bottom end of the tuning dial it is very difficult to tune - inconsistant tuning, does not smoothly transition through the tuning range, but rather jumps around, then does not necessarily stay tuned in to that frequency well. These problems do not occur at the top end of the dial.

I have cleaned the tuning capacitor on 3 different occassions using various methods, including compressed air, circuit board cleaner, and a combination of both. Every time I clean it, it works great for awhile, then goes back to acting badly again.

Any thoughts about this? I suspect there have been previous posts on the issue, but I didn't find anything...

Thx Scott Kelley

Reply to
Scott Kelley
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After you have cleaned it a spot of Vaseline on the wipers will keep it that way for a lot longer. I use an old ink refill syringe and needle. You have to give it a good squeeze but it puts lube right where you want it!

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Best Regards:
                     Baron.
Reply to
Baron

Hey Scott...

Could the dial cord be binding? Also, advice above about the wiper is valid. It's a brass piece that wipes against the shaft to ensure good contact. Make sure no gunk's built up under there.

jak

jak

Reply to
jakdedert

Air, and typical circuit-board cleaners will remove dust, and a lot of surface contaminants. Neither will remove oxide from the contacts, or lubricate the contacts to prevent metal-to-metal galling.

You can buy commercial "tuner clearer/lubricant" sprays, which I believe combine a cleaning solvent with a light petroleum oil that remains after the solvent evaporates and acts as a lubricant.

I've also had good luck using some DeOxIt spray on the contact surfaces of air-variable capacitors, roller inductors, and the like. It does a decent job at cleaning and deoxidizing the contact surfaces, and provides some lubrication and protection for the surfaces. A noisy roller inductor I flushed-and-cleaned four or five years ago remains clean and noise-free today.

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Dave Platt                                    AE6EO
Friends of Jade Warrior home page:  http://www.radagast.org/jade-warrior
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Reply to
Dave Platt

The ground connections to the center shaft need cleaning - lubrication. They use a copper feeler at each section to make contact to the center shaft. Some Caig De-Oxit D-100L dripped in there and worked around should take care of it. Kind of hard to describe without a closeup picture though.

Mark Z.

Reply to
Mark D. Zacharias

You guys seem to be dead on. I can readily duplicate the problem by putting just the slightest pressure on the ground contacts. I ordered some DeOxIt as you recommended. Thanks a bunch.

Reply to
Scott Kelley

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