[alf]

Hi,

well, C3 and C4 on #2 board have been replaced but no change in the lifter issue.

i like to exclude the lifter/lower gear wheel as it performs basically the same task at the run-out groove of a record without any drama – no stuttering or rattling of anything!

same thing goes for the piston of the solenoid – leaves me with testing TR4/5.

As I see it : when the lifter function is activated a fluctuating power supply is fed to the solenoid……what else could it be ?!

ALF

[alf]

Hi Mark,

I  can verify 12.1 VDC at P3-2 and 12.09 VDC at the solenoid. So far I haven’t checked

C3 and C4 which are easy enough to replace. It had been suggested to replace those two caps but am almost certain both are fine  ?!

will repirt back once they have been replaced. Thank you for your contribution ?

ALF

 

[alf]

Hello,

no, its not what you are referring to !
A bit tricky to describe but the piston moves freely when it moves.

what however happens when the lift is activated is that the piston moves forwards and backwards very quickly which generates a rattling noise via the lever arm “connected” to the gear wheel that operates the up/down lift.

does that explain it any clearer ?

ALF

[alf]

hi,

perhaps a better word to describe the solenoid issue is ‘solenoid rattling’ ?!

which only occurs when the lift is engaged (< or >)

ALF

[alf]

Hi John,

yes, I will do that after all those turntables are off the workbench and will repost the findings – wish me luck ??

ALF

 

[alf]

Hi All,

still waiting for the Beoparts order…..in the meantime after some research I decided to replace the faulty 92PU51 transistor with a M BD 508 type which is working fine.

The motor control function is now fully restored and the Beogram is back in business

thanks to all interested members.

ALF

[alf]

Hi All,

Just a brief summary since I started that post regarding speed issues on my 4002 table.

replaced were the old speed trimmers with 25-turn Bourns trimmer, a modern speed-switching relay was installed and finally the DC platter motor received new bearing, which in the end settled the issue !!

all playing nicely again ? or should I say “beolovely” ?!

ALF

 

[alf]

Thank you for the info – part has been ordered 3 weeks ago – still waiting……!

ALf

[alf]

Thanks Mark,

i will take that on board (if I can find one!!!)

perth isn’t exactly a semiconductor hub.

ALF

 

[alf]

I guess I don’t  have to answer Q3 &Q4 ………

not something I suspected, but the shop sold me two 2 KOhm trimmers instead of

5 kOhm trimmers ??

too much trust is not often rewarded – now both speeds can be set and are in fact

set now.
The W/F is very minimal and will improve further after the DC motor has new bearings.

ALF

[alf]

My thoughts exactly, the motor should not run faster with a worn bearing !

running faster is not so much the problem because there are trimmer pots to adjust.

the issue is that I can not regulate sufficiently down the 33rpm speed – I can do that with the 45rpm speed though.

i only have one 45 single and can adjust that by ear as I know Bonos voice. To my ears

the speed sounds correct and steady.

the same applies to the 33rpm setting apart from the regulating down issue, which I seem unable to do…it is just a tick too fast, which I can see on a strobo disc and hear – I know McCartneys voice.

both trimmer pots are 5kOhm 25-turn Bourne trimmers.

Both 2R2 and 1R15 are on the edge of their range but it is still too fast spinning.

not sure if that is helping a diagnose ?

ALF

[alf]

Hi Lanola,

sounds like you need to fit new belts.

see Beoparts shop !

good luck

ALF

[alf]

Hi All,

I replaced IC 6104, readjusted the Focus Offset (=410mV), checked the laser current (=48mV) , replaced the drawer belt with an interims one until the original one will arrive.

so far the player works fine again, although I am not entirely sure what impact exactly

the new IC6104 caused ?!

For now ‘case closed’

ALF

[Author]

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