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

Scott Kelley wrote:


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

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!
--
Best Regards:
Baron.

Scott Kelley wrote:
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

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

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.

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.

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

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!

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.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

"jakdedert" wrote in message
...
Scott Kelley wrote:
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

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

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.

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.