Wurlitzer 3020 Wallbox

Hi,

I have been repairing a Wurlitzer 219 stepper and 3020 wallbox for my 1100 jukebox.

I am very pleased with the results and the wallbox selects the correct record every time.

However, (about 50% of the time) it also selects the record immediately prior to my selection.
ie: if I select record #6, record #5 plays followed by record #6. Also if I select record #15 it plays record #14 before it plays record #15.

I thought it should be an easy adjustment and fix however, I cannot get it to work correctly and just make my selection.

I have adjusted the stepper contact arm and polished and adjusted all the points in the stepper and wallbox (at least 10 times).

Can anyone provide me some direction on what I may have missed?

Kind Regards

Gordon...

Hi Gordon,
IMHO, that problem can only be in the number wafer of the stepper. I am not at all familiar with WurliTzer steppers, but if Guardian built, like most of the others, sometimes the "locking screw/ plate" on the wiper, comes loose and allows the wiper arm to rest n two rivets as the selection being made. BTW--also IMHO, the wafer rivets do NOT need to be "cleaned" in any fashion--they should be dry and free of "gunk", however. Ron Rich

Ron,

Thanks for the reply.

I thought the same, so I adjusted the wafer as far as possible.

It has an eccentric cam stop which I moved so far one way it played a different record.
But it still played 2 selections. I moved it all the way the other way with the same results.

I know there is something I am missing, but I cannot work out what it is.
I think a relay may be staying energized for too long or energizing too soon.

Gordon..

I think a relay may be staying energized for too long or energizing too soon.

Yep, that is probably what is happening IF it only does this from the stepper.

Use some ingenuity to hold the stepper wiper in-place after the w-i punch. The idea here is to determine if the hold magnet is releasing too soon and allowing the wiper to pass two rivets while the pulse is taking place.

Also, be sure there are no extra pulses being introduced by the wallbox causing and extra punch
The key here is to observe the relays.

This really old stuff is outside my area of interest..but steppers are steppers so....

Rob

Hi Rob, Gordon,
I don't recall ever seeing a "relay problem" in this area-- (Contact adjustment--sure !!), however, I can see it's possible--most likely a magnetized armature/weak tail spring ? On rare occasions, I have found "Seeburg steppers", that have had a timing problem caused by a resistor changing value ( small in size--mind says either 18 or 36 ohm ?). Also, a "slow motor" in a wallbox can cause "timing problems"---
One other thing I can think of--if "someone adjusted" the ratchet coil so that the armature does not fully pull the wheel to a position that the"dog" can hold it, it may stop "between two rivets" ?
Ron Rich

Ron, an example of stepper relay problems I've dealt with:

-Residual magnetism in the transfer RY. All pulses pile on the letter stepper w/resulting no W-I and no scan.

-Overheated stepper coil as result of a box stopping on a rivet. The result was shorted turns in the coils and large increase in current draw. I prevent this in the Seeburgs by using a half-watt 100 ohm resistor in the plate ckt in place of the 1 watt. On the wallboxes I also use a relay tied to the motor ckt in each box that disconnects the signal line except when the motor is powered.

The low ohm resistor in Seeburg/Guardian steppers is for the R-C constant of the hold magnet. If either component changes drastically the hold coil can release prematurely. Though this is a different stepper design it can be what is causing Gordon's problem and is the reason I advised him to observe the action of the relays and hold the wiper at it's stepped-up position..

Rob

Hi,

I have not replaced the Electrolytic capacitor in the stepper because I have not been able to find one the correct size.

The manual says......
"Condenser, Electrolytic, 80 MFD, +100 or -10% 100 W.V." (I think it means + or - 10%)

The closest I can find is Electrolytic Capacitor 100uF, 100V.

Will this be OK to fit?

Regards

Gordon....

Gordo wrote:Hi,
I have not replaced the Electrolytic capacitor in the stepper because I have not been able to find one the correct size.
The manual says......
"Condenser, Electrolytic, 80 MFD, +100 or -10% 100 W.V." (I think it means + or - 10%)
The closest I can find is Electrolytic Capacitor 100uF, 100V.
Will this be OK to fit?
Regards
Gordon....

Gordon, that means that it can be as much as 100% higher, but not more than 10% lower. I have found those old 'lytics to often be much higher than rated. Since that is the only 'lytic in there and i don't have a schematic, I'd just jump anything 100V or+ and see the result. Looking at a pic of the 145 stepper, the rivets are so close together, I suspect the wiper is touching two at a time.

Were you able to hold the wiper in-place after step-up and W-I to see how it is positioned?

Rob

Thanks Guys.......

It is working.

I took on your advice and watched what was happening.
The stepper arm appeared a little sluggish so I spent time 'panel beating' it to ensure a good contact. It was a little bent (not much).
I also removed the new capacitor and resistor (that I had installed) and replaced them with the old ones. With the new components installed, the stepper was selecting any record, in any order.
I oiled up the motor in the stepper.
I adjusted the stepper arm and cleaned it's points.
I adjusted the arm very slightly.

So, after that, it started selecting correctly most of the time.
With more test running it is now selecting correctly every time.
Thanks again for your guidance.

Now on to my next problem..........

Thanks for your time.

Regards

Gordon...