ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Super job!
Having got one hell of a kick from the satisfaction of the repair, it's kind of a "let-down" just to listen to it, and think "What, there's nothing else left to do?"
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It's true, I am anxious to get started on another project after the successful repair, but I really enjoy sitting around listening to my favorite music again on the finished turntable. The fact that the music sounds so good and is playing on something I was able to restore is quite gratifying.
I know the feeling. I've been listening to the Beogram 1000 since I fixed the motor!
This makes ours lives more interesting every single day. Trouble is, the other halves don't really see the point and require much attention as well...
Jacques
My goal this weekend was to complete my fifth and final (for now) Beogram 8002 project. This turntable was in pretty decent shape. Still, it had quite a bit of dirt and due to its age I decided to replace the electrolytic capacitors. No need to repost the same pictures as I have already posted in this thread on the first four BG8002 projects... so I will just post some pictures of things I left out showing of the other restorations.Here is why, at the very least, these turntables need to be opened up and serviced. Old grease has built up dirt and started to harden in some places.
Someone on the forum was asking about the screws used for the Beogram 8002 feet. The rubber feet don't have screws really, the feet are plastic and have and extension that snaps into a hole in the chassis. Here is a picture from the inside of the BG8002.
The recap on this Beogram went smoothly. After doing several of these it has gotten easier. The electrolytic capacitor I hate replacing the most on these BG8002 units is the one inside the processor housing (C28, 47uF, 10V). It is in a difficult place to remove and replace. You have to be very careful.Here is the old C28 removed.
With everything cleaned, re-lubricated and recapped, this Beogram was running very smoothly. In going over the service manual mechanical checks I noticed the horizontal parallelism of the two arms (tonearm and detector arm) was off. The tonearm sat a little higher than the detector arm. Unfortunately in this case, the adjustment screw is on the underside of the tonearm assembly. This requires removing the tonearm assembly to make the adjustment. I have never done that on the Beogram 8002 as the other ones I restored didn't have this issue.Here is the arm assembly removed from the rails so the horizontal parallelism adjustment can be made.
While I had the tonearm assembly off the rails, I cleaned the parts really good. The ends of the large rail has rubber pieces that fit into metal sleeves. The rubber looked a little dry so I applied some rubber restorer on the ends. Hopefully that will extend their life.
The next step was to re-assembly the tonearm assembly on the rails.
On the previous Beogram 8002 projects I didn't do any calibration on the tonearm tracking force. I just used my tracking force scale afterwards when I was ready to use a cartridge and moved the tracking force slider as I looked at the scale. On this last project I decided it would be nice to at least attempt to calibrate the tonearm so the slider indicator at 1 gram actually was 1 gram of tracking force. I made the adjustment similar to how I did the Beogram 400x turntables. First I set the tracking force slider to the 1 gram position. Then I measured the actual tracking force. If it was not 1 gram, I adjusted the counter weight of the tonearm to get the correct reading.Note: For this procedure I unplugged the Beogram, removed connector P4 from the main board so the turntable would not rotate. Then I plugged the turntable back into AC power and could operate the turntable tonearm into position to make the tracking force measurements. Don't unplug and plug in the P4 connector when the Beogram is plugged into AC power.Depending on how anal you are, this tracking force calibration can take a while...if you insist on getting exactly 1.00 grams for the 1 gram position on the indicator. I liked the way the Beogram 400x turntables have a screw to move the counter weight better. On the Beogram 8002 you have to loosen a set screw, then manually slide the counter weight by feel.
I was hoping to be in the home stretch of restoration and just finish up the panels. However, in testing the Beogram 8002 operation I am having an issue with the tonearm set down solenoid. I saw this before I took the tonearm assembly off the rails and was hoping the better cleaning and lubrication would fix it. The problem I am seeing is occasionally, the tonearm will not set down. The turntable logic knows it should set down as I can hear the muting relay click. Looking at the solenoid, I can see that it doesn't move all the way back when it fails to set down. Sometimes the solenoid works properly and goes all the way back. The movement felt smooth when I had the assembly removed. I guess I'll have to hook up some probes and monitor the voltage that controls the solenoid to see if it is a control problem or a solenoid problem.Here is the solenoid disengaged.
Here is the solenoid properly engaged where the tonearm drops to play.
sonavor:The electrolytic capacitor I hate replacing the most on these BG8002 units is the one inside the processor housing (C28, 47uF, 10V). It is in a difficult place to remove and replace. You have to be very careful.
Seems similar to the cap inside the processor board shieldwork in pizza box Beomasters. They are very dificult to remove because the circuit board with a heavy ground plane conducts all heat away from the soldering spots. I tend to just cut the old cap off, leaving enough stubs on the board to solder the new cap on them. Much easier and helps to avoid circut board damage.
--mika
That's a good tip Mika. It would still be my least favorite capacitor to replace though :)
This morning the Beogram tonearm lowering and lifting appears to be working properly. I didn't do anything further so I'll have to put this turntable into daily use for a while to determine if it has a problem or not.I decided to monitor the solenoid with my oscilloscope. The circuit as shown from the service manual is here. I connected my scope probe to P3 pin 1 for the signal and ground to P3 pin 7.
Here is the actual connection
When the solenoid is engaged, it moves slowly to lower the tonearm to the record. Here is what the solenoid activation signal looks like. It reaches a maximum +4.8 VDC on this turntable in about 1.7 seconds.
Raising the tonearm is very quick, it takes 80msec.
sonavor: While I had the tonearm assembly off the rails, I cleaned the parts really good. The ends of the large rail has rubber pieces that fit into metal sleeves. The rubber looked a little dry so I applied some rubber restorer on the ends. Hopefully that will extend their life.
The rubber at the rails end is only found in US models. European models are steel all the way.Reason is that it was found that the european parts would pick up the tiny 50Hz vibrations form the transformer and it wouldcause the rails to vibrate along ("sing") in standby due to frequency interference.
Here the 50Hz version:
and here the 60Hz like yours:
Not many owners consider this when converting from 50Hz to 60Hz.
There are minute changes elsewhere too, the transformer etc...
Martin
Thanks Martin, I appreciate the additional information.This weekend I was able to complete my restoration on my final Beogram 8002 of the backlog. This is the one that had exhibited a problem with the tonearm not dropping so I will have to use it frequently for a while to verify the problem is fixed. I am hoping it was just a signal problem and the resoldering of the board connector mounts took care of it.
During my wrap up of this deck I had to open it up one more time as I discovered the Detector Arm height from the platter deck was only 18mm. The service manual (page 5-1) calls for 19.5mm. Adjusting the height of the Detector Arm meant re-adjusting the horizontal parallelism on the tonearm. Easy to do...but requires taking the tonearm assembly off the rails (again). Now I believe this Beogram 8002 is fully restored. I am going back to my other three 8002 units and double-checking their platter to Detector Arm height. I also like having the tracking force calibrated so if I have to open the other units to adjust the arm height, I will also calibrate the tracking force.Here is the adjusted Detector Arm height completed.
Here is the service manual adjustment procedure. You can see in the diagram why you would adjust this Detector Arm first, then later do the tonearm to Detector Arm horizontal parallelism adjustment.
sonavor,
What did you find for the platter height to sound best? Some say the aluminum platter part level with aluminum surround or slightly higher. I have been trying to adjust mine for best sound with zero record surface noise. I had one setting where the platter was even with the aluminum surround plate and the sound was wonderful but the right channel had surface noise while the left didn't. when I got the table to be quiet then the highs in the left channel were sizzly. not a lot but enough to irritate. Any suggestion?
Thanks.
I adjusted the suspension springs for the floating chassis so the turntable top surface is about 2mm higher than the deck cover plate. That is per the service manual. However, you must try and set the distance between the tonearm/detector arm top surfaces and the platter top surface to 19.5mm. That 19.5mm setting would be more crucial to the sound as it affects how the cartridge will meet the vinyl record. The 2mm platter height to the deck cover plate is for the ideal spring suspension position so that is what I try to set on my BG8002 decks. With the 8002 adjusted to factory settings, any surface noise you hear will most likely come from the vinyl record. Remember, there are a lot of variations with the vinyl record media. Vinyl records come in different thicknesses, the center holes are not always perfectly centered and there is often a little warping with the disk. Those are things you just have to live with. All you can really do is adjust the turntable to the ideal specifications set in the service manual.
I have a few warped records and while they definitely produce some noticeable surface noise on the lead in, the 8002 manages to play them quite well (even at 1 gram tracking force). I try not to play or keep many warped records though as they put a lot of extra strain on the cartridge suspension.
-sonavor
The top of the detector arm is to be level (at the same height) as the tonearm. So when you set the 19.5mm distance of the detector arm to the platter surface, that should also be the distance of the tonearm. I should have mentioned the service manual has another adjustment procedure calling for setting the tonearm level with the detector arm.
It still don't see how it would make any difference to the sound quality, the tone-arm adjustment screw only affects the tone-arms rest position. It doesn't actually change the height of it. All the screw does is prevent the tone-arm counter-weight falling too low and causing the tone-arm (cartridge end) to sit higher. Its purely cosmetic. The height off the sensor arm is important as it won't detect correctly if it is set too high.
The 19.5mm will be the starting point for the tonearm lowering to a vinyl record, right? That would affect the angle of the stylus to the grooves I think. There are a number of mechanical position adjustments (from 5-1 to 5-3) in the service manual that are important to the resulting sound I believe. Since I am not an expert, I can only go by the service manual instructions as the way to properly set up the turntable for service. The adjustments have worked for me on the Beogram 8002 turntables I have had an opportunity to work on. It was mentioned that the turntable platter needs to be level, that is very true as well. The suspension must be level and the 2mm platter height (over the deck) should be consistent all the way around. I haven't run into any problems on my BG8002 turntables with the decks being level once I had gone through all of the mechanical adjustments. My point is that all of the 5-1 through 5-3 adjustments should be made and should be attainable during service of the turntable. If all of those adjustments are set and the resulting sound is not satisfactory, the problem is likely the cartridge (suspension, tracking force, stylus condition) or the media (warping, center hole not true, etc.).
The point I am trying to make is that certain adjustments have no impact on the sound quality.The tone-arm height adjustment screw doesn't change the height of the pivot, only the resting position. Therefore it will have no impact on the angle of the stylus whatsoever. Neither will the platter height as both the tone-arm carriage and the platter are both attached to the floating sub-chassis in fixed positions. As long as the platter is level and the suspension has enough head room, and the sensor arm is at the correct height to detect the markings on the platter to enable record detection. Everything else is just cosmetic... The only adjustments that will affect the sound quality are the azimuth of the cartridge, ensuring that the tonearm is at 90 degrees to the carriage rails, and the diaphragm (for linear motion) is set correctly to keep the stylus in the centre of the groove as the platter rotates...
And of course ensuring that the tracking force is properly set....
Today I readjusted my VTF and made sure with my Mana spirit level that the table and platter level which I found out the table itself was not level. Leveled the table leveled the platter. Put an LP and I was in sonic heaven! The groove noise was gone on the right channel and the soundstage/imaging was dead center. No more sizzling in the left channel that I had described yesterday in my post. All groove noise is gone from all records except those that had it already from the Thrift stores where I bought them. When Micro line or Shibata type tip cartridges are set properly the surface noise of LP's should be totally quiet unless there are scratches on the LP's. Clean records help too! ;)
I built a SUT using the Sowter MM 1090 step up transformers since my MMC 20CL didn't have enough output for my Tube Phono preamp. Now with the SUT I have 5mV output and the BO Beogram 8000 now sound really nice and way better than before.
Thank you to everyone here for there help and info, I really appreciate it.
Hi all,
I'm new owner of a BEO system (Beomaster 8000, Beogram 8002 and Beocord 9000) and I need to repair the Beomaster and Beogram.
Well, my beogram don't work, when I press play button, the plate is turning but tonearm don't move. There is no light on the arm.
What can I check first ?
I already order MArtin's capkit to recap my beogram, I'm waiting it :)
Thanks for help
It makes no difference if a record is not on the 8002. It should move the tone arm either way.
Most likely the arm drive belt.
//Bo.A long list...
Or arm light bulb.
GReg: Hi all, I'm new owner of a BEO system (Beomaster 8000, Beogram 8002 and Beocord 9000) and I need to repair the Beomaster and Beogram. Well, my beogram don't work, when I press play button, the plate is turning but tonearm don't move. There is no light on the arm. What can I check first ? I already order MArtin's capkit to recap my beogram, I'm waiting it :) Thanks for help
Hi and congratulations on some great components (all of them are favorites of mine).
Anyone reading through the various repair posts in this thread should (hopefully) conclude that a Beogram 8002 acquired used and not yet restored will need a full restoration at some point (hopefully sooner than later). I have done quite a few of these turntables now and can report that on two of them, I did the minimum in getting them fully functional again. In both of those cases, problems later arose where I had to go back in and do a full restoration. So my recommendation is that you plan to doing a full restoration of your Beogram from the beginning - Replace the capacitors of course, resolder the board connectors clean and lubricate all of the moving parts (that require lubrication) and perform the service manual adjustments (tracking force, platter height, tangential tracking sensor and left/right tonearm movement voltages). Compared to something like the Beomaster 8000 the Beogram 8002 electrical restoration can appear to be much simpler. However, care must be taken as the solder points are small and a lot of stuff is on the two boards. Plan on going slow and checking everything. I found it much easier to do the restoration by completely removing the turntable chassis from the cabinet. Here is a reference link to my Beogram 8000 repair thread. While there are some things very different between them, the repair methodology is the same. I think there should be some additional restoration information you might find useful in that thread.You will also need to check your MMC phono cartridge condition. What cartridge came with the turntable and what condition is it in?
Hi sonavor and thanks for the link.
I already remove the pcb from the cabinet, I will check connector soon.
The cartbridge is a mmc4 but the cantilever seems to be a few bended. I will post pics of it soon.
You will love that turntable once you get it working. I have 3 of them.
If you have to replace the cartridge I would not get too hung up on mmc1, mmc2, or mmc3 I have all three and they all sound about the same. I know on paper they are different but there is really not much of a difference audio wise. Soundsmith makes brand new mmc clones.
thanks ;)
I already own a beogram 4002 with MMC20S and I love the sound
GReg: Hi sonavor and thanks for the link. I already remove the pcb from the cabinet, I will check connector soon. The cartbridge is a mmc4 but the cantilever seems to be a few bended. I will post pics of it soon.
Here are a couple more links for your other system 8000 component restorations. These links should give you some idea of they type of restoration work needed - Beocord 9000 and Beomaster 8000. Also check out member, Beolover's Blog for some nice videos of these type of repairs.For the whole 8000 System I also recommend adding the MS-150 speakers and the SC80 System Cabinet. The cabinet has a cool hidden section in the back with a removable access panel at the rear of the record album tray for all of the system wires. So you can hide away all of the wires from view except for just the two wires necessary to the speakers. -sonavor