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Hi all! First time posting on this forum, I've wanted a beogram for quite sometime and I just jumped on a set of two 4002s tonight that I found on OfferUp. The one that seems to be in the closest to working condition is a 5523. Neither of the two have a cartridge, I plan to address this later, but in case it has bearing on my problem I deemed it worth mentioning. I'm very excited to get it going. So far so good.
platter turns, all seems well, however the tracking arm does not read a record, the tonearm goes all the way to the center and back out. Manually dropping it with the button does not work. There is no click from the solenoid or any straining noise. the light seems bright to me.
I pulled out the sensor and the Photocell lens looks a tad hazy, I was able to clean the lens under the light but I can't get to the rearward one. Is there a trick to cleaning this that won't require complete disassembly of the arm? Could I pop the clear plastic lens off and reglue it after cleaning? finally, could the reason the arm isn't dropping be the lack of cartridge throwing the weight off? I'd prefer to get the arm dropping before I drop a chunk of change on the cartridge if possible, but it it's absence could be causing the problem I'll jump on one tonight.
Thanks in advance! Excited to be a part of this community.
hi
Good to see another machine getting repaired/restored to service, first thing is to post some pictures....there are lots of threads on the forums detailing similar issues to the one your having and there are lots of people more than happy to give some guidance on how to resolve them. I would think its unlikely to be a dirty lens on the detector arm, i dont think i have heard of this in any threads, you need to look to the switch contacts first....these often cause issues by sticking in the closed position, The absence of a cartridge wouldnt prevent the detector arm stopping the carriage at the appropriate place when a record was on the platter, hows your electronics skills? you will be asked to measure signals at various points in the course of the project if it turns out to be more complicated than a switch contact......but do look at them first.
Good luck....Craig
Hi,
My experience is that the arm won't lower without the weight of the cartridge, the couterweight keeping the arm straight.But if the relay don't click, it is likely (also) another cause. As Craig suggest, you must put a record on the platter to see if size detection works: even if the arm wont lower, the arm should stop above the record rim and the speed indicator ligthen accordingly.
Which make me also think that without a record its normal you dont hear the relay clicking, since it detect no disc, so no need to lower the arm.
I would recommend to not dismantle anything without knowing what you do and before having extensivley read some topics here on Beoworld: plenty of informations on this deck.
But if you want to assess the common points, one thing you can do is to remove the top plates, put a record and start the deck in the dark: you should see little lights glowing inside on main boards: one close to the arm support, another one under the 2:30 PM zone (if the platter was a clock!). If both shine, chances are the transport mechanism will work after the usual adjustments.
Thanks for the help so far! I daily drove an old Jaguar for a while (maintained entirely by me), I used to tinker with old phones and computers too, so I'd like to think my electronics skills aren't half bad. I know my way around an multimeter, but I haven't really done anything quite like this before so I'm sure there is tons to learn. I opened her up and grabbed some shots. I 'BELIEVE' I have narrowed it down to the detection arm circuit somehow. To my understanding the light in the ruler is what makes the speed witch from 33 to 45 while the arm is moving across the platter. This happens exactly when the large black area of the ruler is over the sensor area (I looked for a light, but the 5523 is an infrared unit, so I couldn't see it. Couldn't find any blue glow with a cell phone camera either, but I may just not know where to point it.) so it would appear that this is working. The arm also never stops when a record is present. I took a video of what happens when there is a record on the platter with the casing off. https://www.youtube.com/watch?v=V2M2lvaM1yQ&feature=youtu.be Trying to manually lower the tonearm with the up and down arrow button does nothing, which I believe (based on prior threads) would not be the case if the infrared light on the ruler was the problem. At no point does it look like any attempt to activate the solenoid is made. I wasn't sure what contacts you folks suggested cleaning, are they soldier connections, or places where the linkage contacts? The linkage moves freely. What do you folks think my next step should be? Am I missing something about the connections?
It does sound like a record detection problem to me........this pic is of a BG4000 control panel but it shows the switch contacts I would suggest you take a look at, the thin brass strips can get bent out of shape and cause problems......the rest of the machine seems to be working fine looking at your youtube vid. Remove the control panel and take a look inside....
Ah, I was looking in entirely the wrong area. I took the panel apart, all the switches looked good and I took some time to clean all the contacts. Sadly there was no improvement. Where should I look next?
Have you checked to see if the Beogram 4002 lamp (LED) diode for the tangential arm position sensor is functioning?
-sonavor
The light sensor? I haven't checked that. The bulb is illuminated. Should I pull that and check the voltage on my multimeter? I was speculating that if the sensor was the problem the tonearm would lower automatically because it wasn't seeing the record, is this false?
Don't think Sonavor is referring to the lamp on the end of the detector arm, I think hes talking about the LED below 4DI, I suspect it is as one can see the speed changing from 33 to 45 on your video...
Right, I had figured since it was switching over that indicated it was working. I've been reading up in some service manuals. Many of them seem to mention 1TR6, should I desolder and check that first?
How are you getting on with this? did you check 1TR6....do you have access to a scope, it would be good to know if the detector arm sensor is delivering a pulse/no pulse.......the fact that the speed is changing over is a good sign....post some more pics
Craig
This weekend I pulled 1TR6 and I'm getting inconsistent readings of 816 and 822 usually, but sometimes it goes 833 and 868. I do have to really move the leads up and down the contacts a bit before I can get a reading though. Not sure if that means anything. I sadly do not have access to a scope. Could I check the pulse with a multimeter?
I was able to get it more stable to 789 and 792 which I think is probably accurate, but It still fluctuates a bit.
My other Beogram is a 4002 type 5501, if I swapped the board from that one into my 5523 just to test would it damage the 5523?
What else should I be photographing? Thanks for all your help so far.
Those boards are not interchangeable. For one thing, the Type 5501 has an AC platter motor while the 5523 has a DC platter motor. Don't try swapping electrical parts between them.
sonavor: Those boards are not interchangeable. For one thing, the Type 5501 has an AC platter motor while the 5523 has a DC platter motor. Don't try swapping electrical parts between them. -sonavor
Noted. Yikes. Glad I asked.
So, since 1TR6 is seemingly okay (I ordered a replacement just to be sure), should I check 1TR5 next? This may be a dumb question, but how do I check "if the current of 1tr6 is high at low position" as the manual says to check?
Craig: How are you getting on with this? did you check 1TR6....do you have access to a scope, it would be good to know if the detector arm sensor is delivering a pulse/no pulse.......the fact that the speed is changing over is a good sign....post some more pics Craig
Does anyone know of a kit to replace all transistors and capacitors?
pretty sure Dillen still does a full service kit for all the 400x tables
https://www.beoparts-shop.com/
Thanks, I didn't see any for the 4002 though