BeoGram

Re: Beogram 4000 tonearm descent issue

Ariston — Tue, 04 Nov 2008 09:33:14 GMT

Thanks for all the helpful advice concerning the sensor and arm.

I am trying to set the sensor and arm on a 4002. I have the manual and it calls for a tool numbered 3624009. It looks like the tool is a printout. Is this tool necessary? Is it available?

On a related issue, I am able to get the sensor and arm to work (though the tracking is off), if I move the sensor so it is next to the arm. The result is that the sensor and tone arm are not parallel. I have not been able to get them to work when they are parallel. Do you have any advice?

Thanks again,

Kirk

Re: Beogram 4000 tonearm descent issue

Piaf — Mon, 01 Oct 2007 21:51:05 GMT

Thank you Martin,

You have been a great help.

This 4000 is truly been through a lot. And I don’t need to tell you how annoying it is to painstakingly set everything up just so and have the deck perform flawlessly for a few plays and then go out of adjustment again.

The tracking force has been just so touchy. Truthfully it is very close to being right; the major issue right now is the karate chop stylus drop. I will adjust it this weekend.

I’ll attend to the pickup at the end of play at the same time. That one is easy.

Thank you for your help.

Jeff

Re: Beogram 4000 tonearm descent issue

Dillen — Mon, 01 Oct 2007 15:14:21 GMT

Beogram 4000 is a wonderful deck but a beast to adjust ground-up.
You are on the right track (sorry) and the tracking force adjustment can be
offset by adjusting the screw at the rear side of the counterweight.
The drop time is adjusted by means of the little screw ontop of the brass
cylinder. As little as 1/8th of a turn is probably all it needs and you should
lock the screws again using a tiny drop of lacquer or similar. I use nailpolish but
don't ask your girfriend to borrow you hers - you'll never hear the end of it...

Martin

Re: Beogram 4000 tonearm descent issue

Piaf — Mon, 01 Oct 2007 00:50:39 GMT

Hi Martin,

Perhaps I didn’t explain things properly. This 4000 was absolutely “destroyed” in transit from Jersey City, New Jersey to Victoria, British Columbia. Cosmetic issues aside, there were several internal parts broken, most importantly, the bearing that holds the drive shaft spindle for the arm mechanism. Both the wheel and the belt from the spindle were found UNDER the motherboard.

I hand-made a replacement for the bearing as none appear to be available. Bit by bit the 4000 came back to life. However after HOURS of work (30+) once adjusted, with everything working properly…. it doesn’t last.

The tracking is now not pushing hard enough. It is close and the 4000 plays records fairly well, but a little more force is needed. The play quality deteriorates towards the end of play.

Also the pick-up and the end of play which had worked dependably for weeks is no longer working. Just a tiny adjustment, but it begs the question, why all these re-adjustments?

I digress; my question was is there an adjustment for the rate the tonearm drops on to the record? A lubrication problem would case a slow drop and a slow rise…. This is a Karate chop drop and it is going to ruin the stylus. Any thoughts?

Thank you.

Jeff

Re: Beogram 4000 tonearm descent issue

Dillen — Sun, 30 Sep 2007 15:09:51 GMT

Good job so far!

Tracking force is next, check it using a tracking force scale.

Still thin - try another cartridge. There are no electronics in the signal way, just the cartridge, the leads and a muting relay.

Martin

Re: Beogram 4000 tonearm descent issue

Piaf — Sun, 30 Sep 2007 14:08:49 GMT

Hi Martin,

Yes, thanks to BeoWorld I have the shop manual. What's next?

Jeff

Re: Beogram 4000 tonearm descent issue

auric — Sun, 30 Sep 2007 14:07:36 GMT

Martin:

I found the collar around the aluminum cylinder under the tone arm and shifted ever so slightly. The arm now lowers properly.

The deck however still sounds very "thin...."

Derek

Re: Beogram 4000 tonearm descent issue

auric — Sun, 30 Sep 2007 13:51:32 GMT

Thanks Martin!

The arm remains parallel throughout the playing of the entire record but does not drop where it hovers.

Is this a difficult adjustment to make? Is it mechanical or a trim pot?

What about my question regarding the damper mechanism affecting the tracking force?

Best,

Derek

Re: Beogram 4000 tonearm descent issue

Dillen — Sun, 30 Sep 2007 10:55:25 GMT

The arm is supposed to lower exactly where it hovers. If the servo motor activates during lowering of the arm it sounds like your deck is in need of adjusting the tracking sensor. This is NOT the sensor in the arm next to the tonearm but a sensor housed below decks, practically under the tonearm. It's a lamp/interrupter/sensor assembly. Wrong adjustment will also result in a slightly offset tracking when playing and in extreme cases the tonearm will, after playing for a little while, be far from parallel to the sensor arm. The two arms should remain parallel (at least to the eye) at all times.

Martin

Re: Beogram 4000 tonearm descent issue

auric — Sun, 30 Sep 2007 10:30:37 GMT

Hi Martin:

On the subject of the 4000 series decks, as you know I recently acquired a 4002.

I've got two problems with my deck:

1) When you press the tone arm lift/drop control, is the tone arm supposed to slide over a few millimeters to the left as the needle drops?

Unlike my beogram 8000 which will drop the needle directly where I cue the arm, I am unable to get the needle to drop directly above the point where I would like the needle to drop. Is this normal? If not where might I look for adjustments?

2) In previous posts here, I read that the damper cylinder that lowers the tone arm can seize due to aging lubrication and cause the tone arm not to drop at all. My tone arm lifts and drops, but I'm wondering if aging lubrication could also lead to improper tracking force. ie the tone arm appearing to function properly but not really dropping fully.

I suspect that the arm on my deck is not tracking properly because the lp sounds very muffled and without much highs. It is an MMC20EN with tracking force set to 1.5g. Any ideas?

Thanks,

Derek

Re: Beogram 4000 tonearm descent issue

Dillen — Sun, 30 Sep 2007 01:40:15 GMT

Yes, on the top of the dampener cylinder.

Do you have the service manual ?

Martin

Beogram 4000 tonearm descent issue

Piaf — Sat, 29 Sep 2007 21:45:07 GMT

My Beogram 4000 is a definite work in progress. Never in my life have I ever dealt with such a temperamental machine. However my question is why does the tonearm drop like a sack of potatoes?

With lubrication problems the arm drops or picks up very, very slowly. This is not the case here, the arm moves over the record, stops, and WHAM drops like a brick.

On my Beogram 4002, 4004, and 8000 the arms drops gently to the record, however the 4000 it just drops.

Is there an adjustment for this?

Thanks!

Jeff