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BeoGram 9500 Tone Arm issue

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rebos123
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rebos123 Posted: Sun, Feb 22 2015 3:16 AM

Hello everyone!

New member here.  I was blessed to inherit my Mom's BeoGram 9500 turntable and Beocenter 9500.  Everything works flawlessly except that the tone arm does not pickup when the tone arm reaches the end of a record.  

Actually everything did not work flawlessly at first.  When I placed a record on the turntable the arm would not move.  I opened up the case and found that the wire drive had come off.  I rethreaded the wire and now everything works great except the automatic pickup at the end of the record.  I tried adjusting the photo diaphragm but this did not help.

I am stumped.  I know I can just hit the stop button on the keyboard to get the arm to pick up and return at the end of the record, but I would really like it if it did this automatically.  

 

Can anyone please give me some ideas to try?

 

THanks,

 

Mark

rebos123
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rebos123 replied on Wed, Feb 25 2015 2:39 PM

Well after researching some more on the forum I found Condor Audio article about repairing the line of turntable that includes the 9500.  He suggests replacing the 2.2 and 470 uF capacitors, then rebuilding the solenoid.

I am going to replace the capacitors first then see how the unit works........I sure wish someone could tell me what is supposed to happen (electrically) when the tone arm reaches the end of the record...........

leosgonewild
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It should lift up and return to the right side and go to rest.

"You think we can slap some oak on this thing?"

rebos123
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rebos123 replied on Wed, Feb 25 2015 3:32 PM

Hmmm....perhaps I should have been more specific in my question.  What is the electronic process that happens when the tone arm reaches the end of the record.  Something like:

1.  Tone arm reaches end of record groove.

2.  Some sort of voltage changes, or the photo resistor does something to signal the IC that tone arm is at end of record.

3.  The IC sends out some sort of signal to the solenoid to go through the "lift up and return to right side" process.

 

I guess I am looking for someone to help me with trouble shooting this unit.  I.e. - "put voltage probe on point "X" and you should see ??? when tone arm at end of record.  If not, check Y or Z.........

Mark

Dave Farr
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Dave Farr replied on Wed, Feb 25 2015 5:08 PM

Well, if you really want to know, you could upgrade your membership to Silver or Gold and have access to the full Service Manual.

Dave.

rebos123
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rebos123 replied on Wed, Feb 25 2015 5:36 PM

I have the service manual.  I found it in my earlier web searching.  

I guess maybe my questions are either too general or too specific or too vague...

 

thanks to everyone that responded.  i guess i will have to brute force figure the problem out...

sonavor
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sonavor replied on Wed, Feb 25 2015 9:29 PM

Does your Beogram 9500 automatically detect and return when there is no record present?

-sonavor

rebos123
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rebos123 replied on Wed, Feb 25 2015 10:02 PM

When I press "play" with no record on the platter, the platter spins, the "33" lights up but the tone arm does not move.  After a second or so the turntable powers off

sonavor
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sonavor replied on Wed, Feb 25 2015 10:25 PM

Okay, that's right...the BG9500 has a pressure switch to know that an LP is on the platter.  The BG400x - 800x search for a record with their detector arm and return when none is found.  If you have a record on the platter and press the forward cueing all the way in, will the turntable reach the center and return automatically?  Or does it just reach the center and stay there until you return it?

Does the service manual show whether the end of record detection is by a mechanical switch or by some other type of sensor?

rebos123
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rebos123 replied on Thu, Feb 26 2015 12:32 AM

I believe it uses a photo resistor. You made me think of something I need to check. The service manual shows a logic diagram of what the signals into the u controller should be. I need to verify these. I will report back what I find. 

rebos123
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rebos123 replied on Fri, Feb 27 2015 6:21 PM

Well  I checked all the logic signals - everything looked fine.  As I stared at the turntable for another few hours I decided that there must be a mechanical switch that signals the end of record as sonavor suggested..

I refit camwheel 1636 and this fixed the problem.

sonavor
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sonavor replied on Fri, Feb 27 2015 6:31 PM

Great!  Can you show us some pictures of what you did?  It is always nice to visually see what these repairs reference.

Thanks

Dave Farr
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Dave Farr replied on Fri, Feb 27 2015 7:41 PM

rebos123:

Well  I checked all the logic signals - everything looked fine.  As I stared at the turntable for another few hours I decided that there must be a mechanical switch that signals the end of record as sonavor suggested..

I refit camwheel 1636 and this fixed the problem.

Well done for a good repair.  As has been said, pictures of what you did would be nice and thanks for letting us know.

Dave.

rebos123
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Since I already buttoned up the turntable I included diagrams from the service manual.  Hope this helps someone.

 

 

 

rebos123
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Since I already buttoned up the turntable I included diagrams from the service manual.  Hope this helps someone.

 

 

 

rpochi
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rpochi replied on Tue, Jun 16 2020 1:24 AM

Hello, adding on to this post as I have the exact same problem, but the issue remains despite refitting of cam wheel 1636 as described above. The tonearm will not return once it hits the run-out groove, it stays at the center of the record like a manual turntable. Hitting the stop button will lift the tonearm and return it to the resting position.

Brief summary--TX2 5913 was working fine until cord broke, fixed using a screw to the carriage sled.

-Replaced belts for platter and arm motor. 

-Leveled platter, ensured transit screws properly undone.

-Lubricated carriage arms with lithium grease.

-Ensured proper position of tonearm lift lever in relation to the lifter mechanism rod behind carriage sled rods

-Ensured spring positioned on lifter mechanism rod 

-Ensured Optotrak light is working.

-Player otherwise recognizes 12"/7" records, and will not run without a record on the platter. 

Any suggestions would be greatly appreciated! 

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