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Hi, I own two 8002s and need some guidance on how to adjust one of them.
The issue
1. It sets down about 1 mm too soon which causes the needle to miss the edge of the record.
2. It often will lift up and return to off position before the end of the record. No matter where I put the needle on the record it will play maybe 1 minute then it lifts up as if its at the end of the record. Not sure what controls this.
I have the manual for it but its a little sketchy on how to make these adjustments. I can get the cover off the tonearm in the back and that long cover by the lid to access the counter weight screws. Just not sure what to do on the set down.
Thanks
I did make some progress.
Loosened screws C & B on top of the sensor arm and put it at the proper right angle.
The height of the tone arm and sensor are not the same. The sensor is quite a bit lower. I turned screw A from the manual but it did not seem to change the height.
I think the sensor is too close to the platter which causes it to sometimes lift early.
I can't get to the counter balance weight screw as the lid is in the way and I don't know how to remove it yet.
Did you check the service manual and the Beogram 8002 repair thread here ?
Thanks I did not check that thread but I've since looked at it. Very good thread on the 8002, was like a book, glad you finally nailed down the issues.
I might have missed it but did you have pics of the Tone arm adjustment screws?
I have the pickup issue resolved. But I have two more adjustments to make.
1. Tone arm weight - Previous owner had moved it for more weight to get it to play a failing suspension cartridge. So I need to rebalance it. I think I can do this once I get a smaller screw driver.
2. Adjust the height of the sensor arm. Its too low. Manual says 1 screw to adjust it but fails to explain much more on how.
3. Adjust the side to side distance between the arms. I did the sensor but the screw for the tonearm does not seem to do much. The service manual pdf I think had it backwards, they called it vertical and horizontal distance. There is a screw on the side of back of the tonearm that I am not sure if it raises and lowers or moves it side to side.
If someone could help me figure out what the screws in the photos do I would appreciated it.
In the first photo I have the screws marked A thru F. Just want to make sure I understand their function.
A & C - These seem to allow me to move the sensor arm side to side. This indirectly affects the set down of the tone arm. If the end is not square or too far to the right the needle will set down short of the edge of the record. I sqaured it up and now sets down ok.
B - Not sure on this. It was all the way out almost. I screwed it back down but it did not seem to change anything like the manual said. Does A & C have to be unscrewed again for this to have an effect?
D - Tone arm counter weight, need a shorter screwdriver for that one.
E - No idea, maybe just what holds tonearm to weight
F - Two screws adjust the skew or rotational tilt of square arm with respect to the platter surface
G- Large screw, thought it did the height of the tone arm or side to side. Did not seem to do much when I turned. so ??? for now
On my other 8002 these two arms are at the same level when off. On this one you can see the sensor arm is angled down more than the tonearm.
Not sure how to bring sensor arm up.
RAJOD: Thanks I did not check that thread but I've since looked at it. Very good thread on the 8002, was like a book, glad you finally nailed down the issues. I might have missed it but did you have pics of the Tone arm adjustment screws?
On my Beogram 8002 units I didn't adjust any of the tonearm settings. They worked fine so I didn't want to disturb them until I absolutely have to. So far, after a few months of use, the turntables are performing really well. I have a couple more Beograms 8002 units left to work on (later this year) and a couple of Beogram 8000 units (also later this year). So I'll have to see what those repairs will require.
Interesting on the detector arm angle. I will have to double-check my 8002 units. The manual says the detector arm height is adjusted using adjustment screw "A" (in the manual, "B" in your picture).
Screws A & C make the sensor arm loose and you can move it side to side. I just eyeballed the arm with the silver top cover which has a nice straight edge to it. I think it was toed out to the right which made the sensor see the edge of the record before the tone arm was over the edge (there were wider apart) this cause it to set down just a tad early missing the edge of the record.
I am not sure how important have the tone arm perfectly paralle with the sensor is. I would say its close maybe a little pigeon toed while playing.
The sensor is suppose to be 19.5 mm from top of it to the surface of the table. I'll measure it today but its probably more like 16mm. Being this close to the table must make it sometimes gives it a false alarm that the record is over and it lifts up early. I must have changed the height a little by randomly fiddling with the screws as the behavior has stopped.
There are two screws in the manual that adjust the tonearms height and what I call side to side position. The manual calls it vertical Parallelism. The description and the picture seem to be opposite. What they call vertical looks to me like side to side angle adjustment. Meaning make the arms wall eyed or pigeon toed.
Take a look and see what you think.
If the tech guy is not extremely careful (and knows what he is doing), he can very easily bend down -or even break off - the sensorarm by accident, when closing the Beogram after servicing.I've seen this many times.A slight bend is usually more of an esthetic issue than a funcitonal.
Martin
That is good to know. I don't know enough about the 8002 to know what is acceptable and what is not. Just trying to learn what the various adjustment screws really do.
Yes It very well could be a little bent, but I still want to understand a little bit about the adjustments.
This particular unit was just out of the shop and had all the caps replaced and lubed. Its very clean but like you said maybe it got a little bit bent just from handling it. Even taking the cartridge off one has to be careful not to put too much pressure on the surrounding parts.
They are delicate but when working they are probably my favorite table right now. Now when I look at my Techniques 1300 it just looks bulky and 1.7 grams seems heavy in comparison. But that old 1300 can take a beating too.
Some more progress on the tone arm weight.
The previous owner had a mmc4 on it that sounded a bit distorted, he found if he slid that plastic weight on the tonearm to max (2 gram i think) it played better. He then added a bit more weight by adjusting the counter weight.
I still can't get that weights screw loosened. The lid is in the way and 4 small screw drivers from home depot where either too wide for the hole or too tall and hit the lid.
I took a sure cart scale to see what I had to set it at to get a true 1.2 grams for a mm3 I now have on it.
Turns out that .5 grams on the plastic scale = 1.2 grams or around 2x off.
That will have to do until I can figure out how to get at that counterweight screw.
Also noticed that when I push pause the tone arm pops up and sort of teeter totters a bit. On my other 8002 it just stops fast when I push pause or off. Not sure but does that cover offer some kind of dampening to prevent this? Don't want to put it back on until I get the weight right.
Are there any retired B&O techs on this site?
Seems nobody has removed a tone arm on a 8002.
Should I repost this as a different message as this was started out with set down location and not tone arm repair?
I have it back together and it does play. The issue is how loose the tone arm feels compared to my other 8002. On my other one if you squeeze the arms together the one with the needle will snap back to center like its on a spring. Same thing if you pull it wide.
On the one with issues its very sloppy feeling almost like a spring is missing.
Update on the photos and what the screws do.
Screw G in the photo - Seems to be a Cam type screw with a spring rod above it. This cam does seem to lower or raise the tone arm height. It also seemed to change the horizontal position. I am not sure if that spring needs to be below it or above it.
A & C - Screws simply hold the Sensor arm on. If you take them out you can remove the sensor arm. It still has wires hooked to it. Did not see a way to unplug them. The holes are large enough where you can move it side to side to get it straight. The sensor seems to be motion controlled, just moving the tone arm closer to it will cause it to auto lift arm.
B - Brass front screw on sensor. Does nothing, maybe holds metal part to plastic insert. Manual says its an adjustment
D - Counter weight. Do not ever change this. Its set from factory. Can verify weight using a shure cartridge scale. Usually can use plastic slider to compensate. Measuring is tough as have to have unit turned on to lower the arm, and the platter spins when its on in down position. Makes it tricky to get the scale on the table.
F - again no need to adjust, but it tilts/rotates the tone arm clockwise or counterclockwise a small amount.
E - Probably Tone arm mount screw
To me the unknowns are G and the spring clip above the screw. In off position I can move the tone arm over and actually above the Sensor arm using my fingers. I can't do that on my other 8002, it seems to resist any vertical movement. So something is out of place but not sure what.
When I lift the tone arm you can see brass cam screw G moving down. I am wondering if screw G were above that rod (seen in the pic) it would prevent the tone arm from being so sloppy in off position.
I feel as if I am the only one to have disassembled a 8002 tonearm Anyone out there with some knowledge on this?
It is difficult to tell from the service manual diagram where that screw ("c" for Horizontal Parallelism of the Pick-up Arm) is. It says "to be found under the bottom of the carrier unit" but I don't see anything in the exploded view called carrier unit. It could well mean underneath the assembly you have been adjusting.
For me, I haven't messed with the Beogram arm assemblies other than clean and lubricate the drive they travel on. You are getting into an area that I have avoided. The only suggestion I can make is to adjust the ones you can identify the best you can and test how it performs. If it doesn't operate well (sounds poor), you may have to find a replacement arm assembly. However, there surely is a way to get in re-adjusted back into working order if there isn't something broken inside (out of site). If you do go further into the arm assembly, make sure you document well with pictures. Someone here on the forum may spot something.
Try sending a private message to Dillen or Menahem Yachad about the location of the adjustment screw for Horizontal Parallelism of the Pick-up Arm. They have a lot of experience with these units. I wish I had some answers but I have not done any of those adjustments.
I didn't really notice until now what the actual forum group this post was in. I see you reposted your question under the form Beogram section. That is a better location. Another good area is the workbench area. Hopefully you will get better help from the Beogram section though.
Thanks, I did not know where to start the post then saw there was a forum area for Beograms. Hope its ok with the forum admins, don't need a ban for double posting. Just trying to figure out how to get it adjusted correctly.
I have it working pretty well now. But its not correct, something is wrong with the tightness of the tone arm. Its very floppy when its in the off or up position.
My other 8002 is not like this and I'm thinking the previous owner while adjusting it got something out of place. I just not sure what it is.
What ever stops the tone arm from moving past horizontal is off. I can grab the tone arm and move it probably 3/4 inch up and move it so the tip is over the senson arm. If I try that on my other 8002 the tone arm does not budge at all. Its solid. When I move the tone arm side to side it have none to very little resistance. On the good 8002 the tone arm will snap back to center if moved left or right. Almost like its spring loaded.
So maybe its missing a spring or something.