58 wonderbar seek

[Brad H.]

Has anyone had or has this problem on their wonderbar, my seek will work fine for awhile, then click or thunk, then stop seeking until I wiggle the (right) tuning knob around a bit, then it will start working again and this keeps on going over and over, seems the tuning knob jumps when the thunk happens, is something pinching the knob from moving on its own (if that is what it is supposed to do?) radio was 100% restored by Grossmuellers several years ago and looks perfect, any idea on a fix without sending it off for a check up? (Gulp) Thank you, Brad.

[Stephen R.]

Re: 58 wonderbar seek

I had heard that one of the tubes in the radio may work itself loose and cause that problem. May want to try making sure all of the tubes are properly seated.

[Brad H.]

Re: 58 wonderbar seek

Thanks Stephen. would that require dismantling everthing, any other possibilities would be helpful from anyone knowlegable with wonderbars, thanks, Brad.

[Joe M.]

Re: 58 wonderbar seek

Once you remove the cover, the majority of the tubes will be visible. Some tubes may be located under a metal cover that can be removed. Use a compressed air can like you use on computer equipment to gently blow out dust while you are in there.

[John F.]

Re: 58 wonderbar seek

Call Jerry Rudbeck (864)363-0947. He rebuilt my Wonderbar and is a guru & all-around nice guy to talk to.

[Jerry R.]

Re: 58 wonderbar seek

Has anyone had or has this problem on their wonderbar, my seek will work fine for awhile, then click or thunk, then stop seeking until I wiggle the (right) tuning knob around a bit, then it will start working again and this keeps on going over and over, seems the tuning knob jumps when the thunk happens, is something pinching the knob from moving on its own (if that is what it is supposed to do?) radio was 100% restored by Grossmuellers several years ago and looks perfect, any idea on a fix without sending it off for a check up? (Gulp) Thank you, Brad.

There are two solenoids in the radio Brad. One resets the dial mechanism (and tuner) back to the left. The second one cocks the power spring that runs everything (primarily the treadle). When this happens, the clutch cups on the (tuner drive shaft) treadle separate so that the main tuning shaft doesn't have to be turned also. In other words and in simplified terms, the load on the solenoid is reduced. If your tuner knob shaft is jumping left or right, this is a place to start. Seeing it move in or out a little is not abnormal.

So, I'd speculate that the clutch cups are not separating reliably when the mechanism is resetting. It is very common for the sleeve over the treadle shaft that supports the exterior clutch cup to have so much dirt and hardened grease inside that the cups won't separate well (if at all). Because that's not in service manuals (which dealt only with new radio parts and conditions) and because I've never seen a shop address that condition as part of a refurb (and I've seen a lot of 58-62's), I'd recommend you start there. It's not for the faint of heart and you must be careful not to affect any of the other adjustments (switch trip points or part mesh tensions).

I have a lot of respect for Grossmueller's but I do not know how far they go with their refurbs. You might be wise to talk with their radio guy on the phone and see what he thinks. He already knows the radio and can review his repair notes.

You can put it on the bench and pop the cover, hook up pure DC (no battery chargers!) with 10 to 12 amps of reserve current and watch what happens to the clutch cups as the solenoids function. But be careful poking around too much until you understand how the mechanism works. Fixing them is more art than science at their age.

Bear in mind there are several other problems that could cause what I believe you're describing but this one is quite common. Another one deals with the tension between the speed governor drive gear and the associated gear on the tuner shaft. If tension at that point is too loose, things jump around erratically and often get stuck.

Good hunting!

_______

John F. - you know he's really a cranky old coot! Good to know you're doing well and thanks!

[Stephen R.]

Re: 58 wonderbar seek

Yes, you will have to take it out of the car and take the cover off. I'd try the easy fixes first ie the tubes, trying to break things loose (gently). As suggested above, hook up a 12v source (I use an old battery that I keep on a battery tender and that will also hold a charge for doing these type of things) and an antenna, and play with it, carefully, you may get lucky. If you don't you'll still have it out of the car for shipping back to the repair shop.

[Al E.]

Re: 58 wonderbar seek

Jerry, do you recommend spraying electrical cleaner inside of the radio? also where can I find replacement tubes?

Thanks Al

[Philip P.]

Re: 58 wonderbar seek

Al, I would be very careful with electrical cleaner on these older radios some of the insulation used may not like the newer cleaners, as for tubes they are available on Ebay but if you are having problems it is best to let someone with the proper equipment take a look at it.
That is just what over 30 years in electronic tells me. Just my 2 cents.
Phil

[Dan D.]

Re: 58 wonderbar seek

Brad, I recommend you take the radio out and send it to Jerry. I think that is the only way you will get fixed correctly. No band-aids. -Dan-