Tuner Issues w/Zenith H845 - Videokarma.org TV - Video

tlavergne · #1 06-06-2010, 07:16 PM

I have had a Zenith H845 radio for a year or two. It has been a great radio and it has become part of the family. Today as I turned the tuning dial it refused to move more than 1/8 of an inch in either direction (both the tuner and the indicator). I feel the same amount of resistance as I turn the dial as I usually do. It worked great last night. So, before I begin tearing into this radio I was looking for some advice for what it might be and how to fix it.
Many thanks.
Tom

tlavergne · #2 06-06-2010, 08:52 PM

For clarity. The knob physically moves in both directions. It is the station indicator that will not move and as a result the stations will not change.

Findm-Keepm · #3 06-09-2010, 08:48 PM

Sounds like the dial cord broke or is severely slipping. Dial cord is still available - if it's just slipping, sometimes a little rosin applied at the tuning shaft will help. If it's broke, check the Sams for a dial cord stringing diagram.

Cheers,

robert1 · #4 07-25-2010, 08:23 PM

you have a problem that is very common to these Zenith radios. actually, there are two problems. the dial string wear is the result of the first problem. that is the tuning capacitor. what happens is that the grease that was used for the ball bearings on the front of the tuning capacitor has dried out, causing the shaft to be stiff to turn. what happens is that because of the extra resistance, the dial cord is stressed & with the additional stress, it stretches. it also loses it's gripping properties. fortunately, Zenith used a separate string from the tuning shaft to the tuning control & used a separate string for the dial & pointer.

to make things simpler, try lubricating the AM tuning condenser at the front where the ball bearings are & manually work the tuner by turning the pully's on the front of the tuner by hand, back and forth until it loosens up. you also should apply a thin coat of lithium grease across the edge where the dial pointer travels. that helps a lot.

when you go to lubricate the tuning condenser, what you need to do is turn the pulley to where the plates mesh with the other plates, attach a nozzle extention to a can of WD40 (or equivalent degreaser), spray directly into the opening where the ball bearings are, then apply lithium grease around the ball bearings. DO NOT get any spray into the tuning plates.

after doing the above, you may not need to replace the dial string.