Home › Forums › Product Discussion & Questions › BeoGram › BeoGram 6000 – Tonearm/Tracking problem
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Gravity Graham.
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27 February 2023 at 03:19 #44180
Gravity Graham
BRONZE MemberHaving given up on my 4000, I have decided to work on the BG6000 which I have.
It runs well, and drops when it should, and can be run forwards and backwards with no problems.
The silent cct works OK, because sound comes out of the t/t when in play.
However, it is not tracking and requires the motor to be moved manually, in order to prevent it getting stuck in one groove.
I’m probably missing something, but I can’t seem to find any guidance in the manual ???
Any advice will be appreciated !!Location: Cornwall, UK27 February 2023 at 18:28 #44181BRONZE MemberThere is a bulb ? n a plastic housing at the tonearm base that burns out and we replace with an LED kit. You can see if it’s lit. If it is there is a shutter adjustment in the manual. It’s the same for the 4xxx series.
27 February 2023 at 21:10 #44182Gravity Graham
BRONZE MemberMark-sf wrote:There is a bulb
n a plastic housing at the tonearm base that burns out and we replace with an LED kit. You can see if it’s lit. If it is there is a shutter adjustment in the manual. It’s the same for the 4xxx series.
Silly question - What is the identity number on the circuit diagram ? Regards - Gravity G.
Location: Cornwall, UK28 February 2023 at 03:10 #44183BRONZE MemberIt is OIL1; however, that is not as important as its location which can’t be determined by the schematic since it is not board mounted. It is under a black plastic cover held by two brass screws directly to the right of the damping cylinder.
28 February 2023 at 04:42 #44184Gravity Graham
BRONZE MemberThanks Mark – found it ! Will check it later today !
Location: Cornwall, UK28 February 2023 at 21:10 #44185Gravity Graham
BRONZE MemberOK Mark – checked it and it’s lit. However I now have a different problem, with motor control….
It does everything except return or Stop !
I suppose the next thing is to remove the main board, and check the Darlington pairs & diodes !! Onwards and upwards as they say !!
Any known problems with this model ??Location: Cornwall, UK28 February 2023 at 21:58 #44186BRONZE MemberWhen you say “return and stop” do you mean if you press Stop during play it does not return or only at the end of the record? If the later that is typically a leaf switch problem as these easily corrode or get out of adjustment. Do either the “>” or “>>” work when the are is cued up? If they don’t then I would look at the electronics focusing on the caps first.
1 March 2023 at 14:06 #44187Gravity Graham
BRONZE MemberHi Mark, I can cue forward (< or <<), but not return (> or >>).
If I press STOP, it does stop – but does not return.
When it reaches the centre of the TT, it stops, but again refuses to return.
At least on this the electronics can be unplugged for testing, unlike the 4000 !
I think you may be right about the caps – might start by replacing all electrolytics as they are a good 30 years old !!
Tks – GrahamLocation: Cornwall, UK1 March 2023 at 23:41 #44188BRONZE MemberActually, those caps are almost 50yrs old so they definitely are a recommended starting point! I would then check closely for the listed voltages on the transistors in the servo motor circuit as it could be a bad transistor, diode or simply a broken solder joint or trace.
8 March 2023 at 08:02 #44189Gravity Graham
BRONZE MemberWork is progressing slowly ! The power supply electrolytics have been replaced, but still awaiting delivery of electrolytics to replace all the Tantalum capacitors on the PCB’s, before I proceed any further. I may take the time to remove and check the transistors and diodes in the motor circuit…
Location: Cornwall, UK8 March 2023 at 08:37 #44190hcraig244
BRONZE MemberSome pics would be good Graham….
12 March 2023 at 20:51 #44191Gravity Graham
BRONZE MemberSorry guys – been a bit busy, working a different turntable (65 ft diameter)..
I’ll post a couple of pix, hopefully tomorrow (Monday)Location: Cornwall, UK13 March 2023 at 10:12 #44192Gravity Graham
BRONZE MemberHere are some pictures ! TR22 was u/s, so changed it out while replacing the Tantalum capacitors.
I also switched out the supply filter capacitors (old electrolytic) – for 2 separate new electrolytics (The 4000uF was replaced with a 4700uF at this point).
All back together and working (ish) – Still need to fix my BeoMaster 1900 !!Location: Cornwall, UK13 March 2023 at 11:48 #44193GOLD MemberCongrats!
“WISE GUY MOD ON”:
When you used shrinking tube at the reservoir caps, why did you not put it over the soldering?
It’s a 4700 uF, keeps a lot of power inside when you touch chassis ZAPP!, don’t ask me why I know ;-))
I’m missing the clamp for the cap, maybe with some feltpad underneath to get it tight fit.
I would have mounted new pots on the mainboard while I have the unit already open. The speed trimmers could be precize spindle trimmers so it’s easy to get the right speed at 33/44.
“WISE GUY MOD OFF”
Kind regards
Christian
13 March 2023 at 13:48 #44194hcraig244
BRONZE MemberGravity….
Martin (the oracle of all BG4000 knowledge) would frown on replacing the tantalum capacitors with electrolytics, he did explain the reason for this in a previous post of mine when I performed a similar restoration on a BG5000, I do know there are advocates of the replacement with electrolytics (Rudi) however I went with Martins advice and put new tantalums in. You should replace the old electrolytic capacitors with new as they will have dried out and as Christian says change out the skeleton trimmers for new piher sealed trimmers, do this one at a time measuring the settings of the existing one (as best you can) and run the deck, adjusting the trimmer if required, to ensure all is well before moving on to the next one….that way you will know just where to look if things stop working (poor solder joint etc)……so far so good ;¬)
Craig
14 March 2023 at 05:29 #44195Gravity Graham
BRONZE MemberHi Spassmaker – it’s not shown in the photos, but the terminals of the reservoir capacitors have been masked with ‘black-tack’ which will keep them well insulated. Thanks for your concern. They are also held in place by ‘black-tack’.
and to hcraig244, while working on field survey equipment in Houston, if a PCB came in with ANY fault, we always changed out any tantalum capacitors for electrolytics as a matter of course before sending it back out. Even though opinion is divided, I decided to go with that rationale. And as regards the trimmers, on that point I personally like to go with the adage of “if it ain’t broke – don’t fix it” as they are working fine.Gravity G.
Location: Cornwall, UK14 March 2023 at 08:39 #44196hcraig244
BRONZE MemberBest if you dont apply that adage to the cam belt on your car ;¬)
Craig
16 March 2023 at 07:08 #44197Gravity Graham
BRONZE MemberI’ll give you that one Craig ! 😀
Location: Cornwall, UK26 April 2023 at 06:32 #44198Gravity Graham
BRONZE MemberHi Mark – been involved with other projects for a while (Major restoration of a 65ft turntable !) I’ve finally finished re-capping my 1900-2 amp, which is now working.
However, when playing an LP on my BG-6000 it is ‘skipping ahead’. I’ve looked through the manual (obtained from BeoWorld), but can’t seem to find how to adjust the shutter..??
(I can’t find it in the BG-4000 manual either..)
Can you advise, and say on which page I will find it ?
G.G.
p.s. – photo of BIG turntable attached..Location: Cornwall, UK26 April 2023 at 13:00 #44199hcraig244
BRONZE Memberthis is the adjustment for a BG4000……..
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