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DillenModeratorDo you have access to another cartridge for testing?
Martin
DillenModeratorThose do not look right. Measure the cartridge pins when it’s not installed. The pins are looking from the back: L+. R+ L- R- The 740 ohms should exist between L+ to L- and R+ to R-. There should be no resistance between R+ and L+.
Unmuted; When the cartridge is fitted to the arm, the two coils have their respective negative ends connected to signal ground.
This means that if you measure from L+ to R+, you measure the two coils in series (2x 740 = 1480).
All fine.Muted; All cartridge pins are connected to signal ground.
All fine.Martin
DillenModeratorAll fine so far.
The fact that you actually have sound from the affected channel, even if only briefly, suggests that the wiring is fine.
The problem could be with the cartridge itself.
I have seen cases where sound is lost when the needle is on a record.
Perhaps a dying cantilever suspension.
Do you have access to another cartridge for testing?Martin
DillenModeratorIt has been a while since the last Beogram 5000 on the bench, but I seem to remember
when you lift off the dustcover hinge block, a small connector becomes visible.Martin
DillenModeratorCracked solder joints near the relay?
Martin
DillenModeratorFirstly, would I be right that the power relay is by the large transformers, and the muting relay is close to the speaker outputs?
Yes.
(See attached image). I have never got involved with such transformers – might I ask for a bit more detail for “cleaning the contacts” and a view on the resistances shown attached. Some of them are very approximate as they were slowly falling during my measuring them.
Replace the relay. Cleaning will not be a long lasting solution.
I have not yet removed the transformer…
You don’t have to.
Martin
DillenModeratorSo, basically, you are comparing a 45 year old speaker still running on its original
capacitors that, ideally, should’ve been replaced 20 years ago, to two speaker models
that are currently available new in shops – and you find them lacking a little treble?Well… replace the capacitors to grant it just a hint of fairness.
Kits are readily available.Beovox S45-2 is an incredibly well balanced and sounding speaker, but it is not “audiophile” and will never be.
Keep in mind it was merely somewhere in the middle of the Beovox model range at the time.Martin
DillenModeratorMINI 41K? – Are you sure?
Martin
DillenModeratorWhat other speakers did you compare to?
Did you replace the capacitors or are the still the original?
Martin
DillenModeratorI agree on the cleaning. A piece of paper soaked in contact cleaner pulled through the contacts – nothing more, or the very delicate platinum coating on the relay contacts will be damaged.
– And you may find that oxidation from airs moisture already did just that.
So – replace the relay.Martin
DillenModeratorAnyone ever thought -or tried out modding any of their speakers? I have these Beovox S45-2 ones and I do like the imaging but feel like the tweeter driver could be replaced with a better one.
Why?
Martin
DillenModeratorThey are interchangeable.
But if yours is the version with the white “see-saw”-arm between the switch rows, check that it doesn’t bind.
Else – give it a good dose of contact cleaner to shift any dry lubricants in the release mech.Martin
DillenModeratorTwo different switch banks can be found in Beocenter 3300.
One cannot be easily diassembled – and it’s usually not necessary. Most will respond well to a shot of contact cleaner and a little exercise.Martin
DillenModeratorIn Beogram 6500 muting is not done by a relay but by a mechanically operated switch.
This switch does not break the signal paths, – it grounds them. This means, that a bad contact won’t cause silence but instead the muting will fail and sound will be audible when the needle lands on the record and lifts again.If you are sure, your amplifier is good, I agree on:
– Cartridge
– DIN solders
– Broken tonearm wiring inside carriage housing
– Bad RIAA connection inside the Beogram
– Faulty RIAA
in that order.Martin
DillenModeratorThe white head of this arm should be on the other side of the cam wheel, operated by it.
Its head should be riding against a teflon sheet with a thick metal backing plate found under the platter.Take off the cam wheel, the metal plate with teflon backing and fit the arm correctly so that
it swings the tonearm when the cam wheel rotates, dampened to a smooth travel by the spring loaded teflon sheet.Martin
DillenModeratorThe solenoid should NOT be lubricated.
Martin
DillenModeratorThe solenoid is fairly sturdy. An electronic problem could cause damage to it, though.
There should be no oil or grease on/in the solenoid. It should be clean and dry.
Martin
DillenModeratorIf the Beogram didn’t lower the arm itself, it wouldn’t have deactived the muting circuit either.
Pressing down on the tonearm to make the needle touch the record won’t produce sound.Martin
DillenModeratorWhat parts are not available?
Check if the motor bushing touches the metal bracket.
If it does – replace the motor mounts.
https://www.beoparts-shop.com/product/motor-suspension-rubber-bushing-grommet-f-several-beogram-beocenter-models-2/If the motor itself is noisy, it must be taken apart and repaired (most can be)
– or replaced, and a good condition used original motor would be the way forward in that case.Martin
DillenModeratorIn the OP, your first schematics are for Beogram 1800 (= Beogram 2000 but no datalink), and the next is for Beogram 2000 & 5000.
The RX-2 schematics shown in the same manual is wrong. It should’ve shown RCA plugs.
Martin
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