|
|
Post by Hildegard on Dec 27, 2023 10:26:53 GMT
|
|
|
|
Post by jonassandstedt on Dec 28, 2023 10:04:37 GMT
Thanks for all helpful schematics and technical notes, Hildegard. Especially the new schematic for the carriage with DC motor is very interesting. I have studied this and cannot, however, figure out how the reversing of the DC motor works, seemingly being somewhat complicated. I would appreciate if someone could help me interpret the schematics and explain how the reversing of the DC motor works. I have just run the DC motor outside the carriage and note that when the switches are set for running the carriage from right to left, the DC motor runs CW smoothly and quickly – just as it should. When I reverse the switches such that they are set for running the carriage from left to right (which does not work at present), the DC motor twitches a second and then continues to run CW but now vibrates presenting a small noise and runs slower.
Best regards Jonas
|
|
|
|
Post by jukenorman on Dec 28, 2023 15:11:53 GMT
Hi Jonas,
I can help you a little bit. For the A side, T514 and T517 are switched on and for the B side T515 and T516 are switched on (T514 and T517 off). I know this because it tells me in Satellite ESIII manual. But in the ESIII, the control is done by the CCU and not a reversing switch like yours - and I can't figure how the reversing switch does it! I wonder, if in your case, whether you should install the resistor as detailed in the service sheet that Hildegard kindly posted?
Norman.
|
|
|
|
Post by jonassandstedt on Dec 29, 2023 8:55:44 GMT
Thanks Norman,
I will try to add that resistor and see what happens.
It is a little disturbing that the malfunction occurred after my service, as if I accidentally have come to damage something or have not thought about something. One thing I just want to check is that when I re-assembled the carriage, I re-mounted the cam shaft in an arbitrary position, thinking that the electro-mechanics will “zero” itself since the jukebox could be deprived of electric power anytime and needs to be able to start up from any functional mode and/or position. Do you think that I am correct in this assumption?
Best regards Jonas
|
|
|
|
Post by jukenorman on Dec 29, 2023 9:42:00 GMT
Hi Jonas,
Yes I think your assumption is OK, especially since it will play a record in one direction! Playing the record in the other direction simply has a motor direction change - which is your problem!
Norman.
|
|
|
|
Post by jonassandstedt on Dec 30, 2023 10:40:38 GMT
Hi Norman,
It seems as adding the 4,7k resistor will be my next step. I will see what I have in my resistor supply and come back with the result. It may take some time, though.
Best regards Jonas
|
|
|
|
Post by jonassandstedt on Feb 6, 2024 12:25:35 GMT
Hello,
More than a month has passed, and I have temporarily lost my spirit due to the lack of progress. I have now received 4,7kOhm resistors and was about to perform the operation of adding this resistor to the carriage PCB when I noticed that it already was there. In the circuit diagram 218918 from 1986 uploaded by Hildegard December 22, the 4,7kOhm resistor is R584, and indeed my carriage PCB is the one shown in this circuit diagram. Knowing this I tested the transistors involved, T510,T512, T514-T519 without finding any malfunctioning ones and re-soldered all transistors. But testing showed that the problem is still there, the DC motor turns OK in one direction, but when it is to turn in the other direction it revolves in the same direction but slower and the motor vibrates as if the drive voltage is distorted in some way and of wrong polarity. This is strange indeed.
Best regards Jonas
|
|
|
|
Post by jukenorman on Feb 6, 2024 18:07:24 GMT
Hi Jonas,
I'm tempted at this point to say that you're going to have to bite the bullet and procure a set of the correct documentation (go to jukebox-world.de)! I have said it before, the NSM documentation that I have is a mish mash that I have collected over the years, some of whcih I no longer remember where it came from! I also made the mistake of assuming that with a set of ES, ESII and ESIII documents, I had all I needed - massive mistake!
Anyway I have an ESIII description manual that more than 90% applies to the schematic Hildegard posted. The direction for the DC motor is derived from the phasing of AC motor (play motor) and I think that you would appear to have a problem there. You're welcome to copies (two pages that I would have to scan) - I have identified one transistor where the blurb doesn't match Hildegard's schematic (ie I cannot find it) but otherwise I think it's there or thereabouts correct. I also tried verify that the transistor just had another number by cross referencing the ESIII blurb to two sets of ESIII schematics that I have and neither is anywhere close. And that in a nutshell is why NSM regularly drives me round the twist!
Norman.
|
|
|
|
Post by jonassandstedt on Feb 7, 2024 6:59:01 GMT
Hi Norman,
I had a discussion with Hildegard just after Christmas, and she did not think that there is any more detailed description of the DC motor in the documentation (if I understood correctly). I think the most accurate documentation of the carriage PCB used in my jukebox is the circuit diagram 218918 from 1986, so kindly uploaded by Hildegard. But that documentation does not mention that the direction for the DC motor is derived from the phasing of AC motor (or any more technical details about how the DC motor is controlled), so if you have a more detailed explanation of how this works, I would be very happy if you could share that.
Best regards
Jonas
|
|
|
|
Post by jukenorman on Feb 7, 2024 9:44:19 GMT
Hi Jonas,
OK I will scan the pages today and PM you a link! In the meantime I have had another thought - I think you should check the reversing switch more thoroughly. My recollection is that an assumption was made that because the play motor reverses, that the switch is good. I'm concerned that it may be good enough to reverse the play motor but not to drive the logic for the scan motor. I suggest linking out the switch, particularly for the direction where the scan motor doesn't work, it's an easy check so worth eliminating.
Norman.
|
|
|
|
Post by jukenorman on Feb 7, 2024 11:24:27 GMT
|
|
|
|
Post by jonassandstedt on Feb 7, 2024 14:29:08 GMT
Hi Norman,
Thank you so much, this is really interesting to read.
I have checked the switches themselves, and they work fine. I think I also checked the connections from the switches, but this can be chacked again. As you say, the switching may be "semi-good".
Best regards
Jonas
|
|
|
|
Post by jonassandstedt on Feb 7, 2024 15:27:52 GMT
I think T532 shall be T523; in the schematics T523 and T524 are connected to the SPM motor windings.
Best regards
Jonas
|
|
|
|
Post by jukenorman on Feb 7, 2024 17:05:22 GMT
Hi Jonas,
Yes I believe you are correct, now that I've looked at it a bit more closely! It's also probably just a typo, T532 for T523! Do you have access to an oscilloscope? I still think it would be worth double checking the reversing switch first. I might be a bit old fashioned but I have great difficulty understsnding why NSM have created that mess of electronics just to reverse a DC motor - especially when the initial trigger is a reversing switch!
Norman.
|
|
|
|
Post by jonassandstedt on Feb 8, 2024 6:57:05 GMT
Hi Norman,
I agree, I do not know how NSM could have made the change of revolution direction for a DC motor more complicated.
Yes, I have a very simple USB oscilloscope, do you mean that I measure the signal at the switch and perhaps the DC motor feed signal as well?
Best regards Jonas
|
|
