Wurlitzer 3010 - another repair project

[viperz]

Completely took mechanical portion of playrak apart, cleaned/oiled everything, put it back together properly. Adjusted both microswitches and cancel solenoid position. No issues now with registering credits and cancelling them after the songs are selected. Onto selector keyboard I go - the one that was butchered the most.

Someone rewired free/test play switch - spring is missing, and all three wires on the bottom are cut off. When I trigger that switch, selector solenoid behind buttons latches. But I do not understand what should unlatch it. I can select a song to play, but the solenoid stays latched until I shut the power off. There were no credits in playrak when I tested it. Need to figure out what condition unlatches the solenoid...

[jukenorman]

Hi Eugen,
It's not much of a reply, but the functional schematic should show how it's wired! I don't have that manual but if you can't figure it out, post that section of the schematic and we can see what we can figure out.

Norman.

[viperz]

Hi Norman, yes, I am neck-deep into deciphering schematic and trying to trace wires. The problem is that whoever removed the wires, removed them completely. I fully rewired the playrak after I replaced burned out coils, but there weren't many wires. The selector keyboard has a big harness of wires running through it, so it is difficult to figure out what in the world they removed and shorted.

For example, they completely removed button release microswitch, which was normally closed, so I need to find two points where they shorted the wires together, break there, install new microswitch.

The Select light is fairly easy too, I already traced where the wires go, and will connect new wiring there.

But this Free play switch is complicated. I traced the wires, which are already there, but have not traced 3 wires that got removed. What is confusing me is that I do not understand what condition is supposed to release the latched button solenoid. In theory, this switch should only trigger one play. Then after selection is made, my understanding is that the solenoid should release, but it stays latched. I really want to get this thing to release, as this is one of the last things hopefully to repair in this machine.

Here is photo of schematic - I was tracing it a couple of weeks ago. I'll double-check that it is the left set of contacts, which are cut off, not the right set. Cannot attach photo directly to this thread for whatever reason, even though I made it less than 1MB. 

photos.app.goo.gl/d46xQhyUUhmcVGzy5

[jukenorman]

Hi Eugen,
That isn't the schematic I was thinking of - you should have an overall "Model 3010 Complete Phonograph Functional Schematic". I had a look at the 2910 diagram which I expect is similar and I've decided that it's probably going to be quite time consuming figuring it out. The latch solenoid is switched by relay contacts on the ground side and these relays will need to be identified (from their numbers) in order to understand it. As a starter that contact (on the 2910, RY1 or RY16 initially?) must be from a relay that energises when credit is available.

Norman.

[viperz]

Nov 2, 2021 21:57:48 GMT jukenorman said:

Hi Eugen,
That isn't the schematic I was thinking of - you should have an overall "Model 3010 Complete Phonograph Functional Schematic". I had a look at the 2910 diagram which I expect is similar and I've decided that it's probably going to be quite time consuming figuring it out. The latch solenoid is switched by relay contacts on the ground side and these relays will need to be identified (from their numbers) in order to understand it. As a starter that contact (on the 2910, RY1 or RY16 initially?) must be from a relay that energises when credit is available.

Norman.

Hi Norman, I understand this all. That entire circuit is fully working. I can add coin, playrak will add credits, I will select songs, it will play them, subtract credits etc etc. This Free Play switch is on a separate circuit, it does not add credits to playrak, it should allow person who is maintaining the jukebox to add one credit for the test. Mine "adds the credit" and latches the solenoid, but does not seem to want to unlatch it after selection is made.

Do you know what the contacts are that I marked with a question mark on schematic? I cannot figure those ones out.


Yes, it is pretty much identical circuitry to 2910.  

[viperz]

Norman, thank you, I found it through the functional diagram. Seems to work now.

photos.app.goo.gl/bn1f9CPNFTiYTDig7

[viperz]

Let's hope this is the last problem...

I tested all 20 selector coils by triggering 1-2 songs from each section (A1-5, A6-0, B1-5, B6-0... to K6-0). All 20 fired, but 3 selections did not work properly. They all seem to be related to B1-5 sector.

B1 - triggers B6 pin (tried twice)
B2 - triggers B2 pin
B3 - triggers B3 pin
B4 - does not work at all - I can hear the relay firing, but no pin comes up - I can trigger B4 pin manually
B5 - triggers random pins - tried three times, got A0, E5, A5 [EDITED - B5 keeps triggering A0 now).

What should I be looking for? Thank you.

[jukenorman]

Hi Eugen,
Glad you got the free play switch problem fixed, I was way over complicating your issue! There doesn't seem to be much of a logical explanation for your selection problem! I wondered whether there might be a short between the B1 & B6 coils? Do all the B6 coil selections work ie B6, 7, 8. 9 & 0? B5 doing "random" selections is also a bit of a curve ball - although interestingly, the number indexing was correct on your three examples so not totally random!

Norman.

[viperz]

Hi Norman, yes, B6, 7,8, 9, 0 all trigger correctly, just tried them.

It seems definitely related only to B1-5 cluster, but I do not see any logic if B2 and B3 work, and B1, B4, B5 misbehaving like this. Is this the right time to drop the selector junction box with selector itself? It does not seem like a mechanical problem, centering etc - otherwise there would be more and more consistent issues? I tried about ~35-40 selections so far ensuring that at least one per selection coil was exercised, and these are the only 3 selections that do not work.

[viperz]

Schematic says that 1 & 6 share the same drive solenoid. If B1 is constantly triggering B6, where would I find this solenoid?
4 shares solenoid with 9, and B9 works. 5 shares solenoid with 0.

[jukenorman]

Hi Eugen,
The drive solenoid will be within the selector assy but I think you're barking up the wrong tree there. The shared drive solenoid is what determines the number ie B1 or B6, the drive solenoid will have taken up the same position for either B1 or B6 letter coils. And your issue with B5, the drive solenoid again has moved to the correct position - although I've just noticed that you said B5 fired A9 but it should have been A0 if the drive solenoid was in the correct position. And the drive solenoid is fine for every selection except the B1's!

Try B1 to B5 again a few times, see if we can detect any pattern - but yes, it looks like you're going to need to have a look inside the selector assy.

Norman.

[viperz]

OK, so I can see that someone has been soldering around two selection coils, out of 20. That's the ones that don't work of course. I don't know if I really should go ahead and try every single selection at this point.

So B1-B5 coil was tampered with and does not work.

Same with G1-G5.
G1 - G1
G2 - G2
G3 - G2 pin gets tripped
G4 - G2 pin gets tripped
G5 - G2 pin gets tripped

[viperz]

Norman, you're right, I am sorry. I just tried B5 three times, and it did trigger A0 all three times (?).

I will pull the selector off, but what should I be looking for? We eliminated the drive solenoid so far. What would make B1 consistently push B5 pin, and B5 to consistently push A0 pin? B4 - I will look for mechanical obstruction - I can see the coil plunger triggering, but B4 pin does not come out. Same for G1-G5 - why would G2 through G5 all trigger G2 pin?

[jukenorman]

Hi Eugen,
The problem with the G1's would certainly point to an issue with the drive solenoids. I'm trying to remember exactly how that all works, my 2900 manual is a poor quality pdf! There are three solenoids in total. You probably need to get in there, I'm afraid.

Norman.

[viperz]

Thank you, Norman. I'll pull the selector off now. I am still not well versed in the selector logic world unfortunately, so going slowly step by step