Wurlitzer 1900 Centennial restoration

[Ron Rich]

Eugen,
"--12 gram-- " ? what are you trying to do--play both sides of a record at once ? What cartridge is in that phono ? Ron Rich

[viperz]

10-12 grams value is specified in the manual. The cartridge is the original dynamic Zenith Cobra cartridge. I keep seeing value of 8g on the forums... Found another spring-loaded meter, but 48 euros...


www.jukebox-world.de/en/Cartridges/Tracking-Force-Gauge-0-10-g.html

[Ron Rich]

Hi Eugen,
Just my opinion, but that seems awfully heavy, even for a Cobra. If it were mine, I'd attempt to get that down to around 8 grams, if the tone arm will track at that-- Records today are much too valuable to sacrifice to an extremely heavy (or bad) needle. Also, Cobra carts./needles, ain't cheap, nor plentiful ! Ron Rich !

[viperz]

Ron, I do agree with you. I just don't have a tool to measure the force. One referenced in the first link (that looks like original Wurlitzer tool) had no price - there are three sales reps for that company in my province, so I may reach out to them. The jukebox world one is 48 euro plus shipping, which is more than I want to spend for two measurements...

[viperz]

Well, no magic smoke, but a long road ahead unfortunately.

1) Select light comes on right away when I turn on the jukebox.
2) Buttons latch, but selector does not respond.
3) When manually trigger the pin / wobble plate, mechanism starts to move, but it won't lift the record. I have to push the cycle button on the front of the amp to get it to lift the record. So I guess something is not triggering. 
4) Motor originally struggled through the step with pushing down the record lift arms. I helped by hand through first couple of cycles, now it does not do that. Still concerning.
5) Record basket does not move at all. I wonder if I missed the pin underneath when I reinstalled it, but when I rotate it by hand (with mech at rest), I can see the selector pawl moving too?
6) I have to keep pushing the button on the amplifier to advance the cycle through its steps. It will lift the record in the slot, record will clamp, record will play, finish. Then have to keep pushing the button to lower the record back.
7) Pins do not cancel. Not sure how that works.
8) Amplifier plays too quiet, even at max volume. I guess, I will have to disconnect the oscillator circuit after all, and inject the signal directly to first amplifier stage to confirm that it is working.

That's my observations so far. I will have to ask someone to push the cycle button on the amp, so I can watch the selector contacts making/breaking.

[viperz]

I found why mech does not want to advance. There is a very stretched out spring on one of the arms that roll on main cam and supposed to close a set of contacts on the back. Need to figure out correct length for that spring, as this one is completely destroyed.

So the contacts in the photo I guess are supposed to be normally made on the left side by the means of a spring. When big cam rotates, there is a bump in it, that would move the arm attached to the spring, which would stretch the spring a bit and open those contacts. Closing those contacts on the left gets the mechanism moving (i.e. lifting the records, etc.). It is a mute and play switch, according to the manual. 
Photos are here: photos.app.goo.gl/pH6cZeWpDhvXWjCJA

I don't think I have ever picked a spring in my life. Should I just cut off half of my hyperstretched spring for now? 

[Ron Rich]

Hi Eugen,
Yep-- that operates that over center snap switch-- I believe it's the "mute/play" one. I don't think that spring is too critical--just make sure any spring you add is strong enough to "snap" that switch as the cam dictates. Also be sure the roller on the other end of that bracket is turning !
Ron Rich

[viperz]

Hi Ron, thank you. It is a mute and play switch, yes. I found photo in the manual, unfortunately manual must have been photocopied with a potato, since it is not possible to see much in the photo. I found a set of random springs almost locally on ebay for 20 bucks. Will probably start with that.

[viperz]

OK, ordered a set of assortment springs from ebay... should be here in a few days. Original spring is 3/16"-1/4" in diameter and probably 1" in length (1.25" hole to hole with mute/play switch left contacts closed). The kit has some 7/32" by 1" extension springs. Hopefully that's what I need.

Ron, how do I check what I messed up and why the record carousel is not moving at all? If I can see the selector crank rotating over selector pins while I rotate the basket, doesn't it mean that I installed the basket correctly on the pin?

Also, trying to understand what triggers the cancel arm to come down and close the selector pins?

[viperz]

So
a) I have used my finger for that mute/play switch spring
b) Reinstalled record basket - it was off the pin

Now I can tell the following:

1) The cycle works now BUT the selected record is exactly off by one selection compared to the triggered pin in the selector. I triple-checked against photos and remaining silkscreen on selector against screws on the selector - I installed the new silkscreen on the selector correctly. What could be the cause of the jukebox being off by 1 selection?

2) Motor is definitely struggling and sometimes making squealing noises when going through tougher parts of the cycle... Do I need to readjust the motor position relative to the big gear?



Remaining issues:

1) Select light comes on right away when I turn on the jukebox.
2) Buttons latch, but selector does not respond.
3) -
4) Motor originally struggled through the step with pushing down the record lift arms. I helped by hand through first couple of cycles, now it does not do that. Still concerning.
5) -
6) -
7) -
8) Amplifier plays too quiet, even at max volume. I guess, I will have to disconnect the oscillator circuit after all, and inject the signal directly to first amplifier stage to confirm that it is working.

[Ron Rich]

Eugen,
Whatz "one off"-- one prior too. one after. one directly on the other side ?
Are you sure squeal is from the motor ? Did you oil the rest of the lift arm train ?
Ron Rich

[viperz]

Ron, when I try to select B9, it pulls out C9. So it picks a slot just after the one that I wanted.

I double checked that I put the record basket correctly together. A1/A2 label is over the tooth with the indentation in it.

Regarding squeal, I'd have to look further after installing the new spring, as it is hard to look inside while holding the contacts.
I did lube the tracks where I think all rollers go. All rollers that I tried rotate freely. The squeal does come from the area of where motor pinion gears are, but I do realize there are a lot of other things there.
Motor does struggle when going through the stage where it lowers the arm. It noticeably slows down.

[jukenorman]

Hi Eugen,
Is the selection issue one off on both A sides and B sides? It looks like the back stop pawls have maybe been "adjusted"?

Norman.

[Ron Rich]

Hi Eugen,
Find a "rubber band" to replace that spring, for now--- Ron Rich

[viperz]

Hi Norman, unfortunately yes, I had to repaint the top shelf, and back stop pawls were the only thing that I did not mark the original position by mistake. I can see from the bottom where old positions of the washers are, and both arms get through the openings perfectly, but I guess, that is not good enough to adjust those back pawls  I did not check the B side yet, sorry. 

Thank you for a great suggestion, Ron!