ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
I have both and I wonder what the arm next to the cartridge-arm is really doing? It is not like the older Beogram 6000 and 4002 that I also have. There is that "static" arm sensing the platter for a record and it is also a reference for the driving of the arm. So, what is it like in the 5500 and 6500? How is the drive of the arm controlled in them?
Roger Gustavsson
It does nothing but carry the speed display. Purely aesthetic.
The drive is a servo controlled, mechanical drive with string and gears. Simple, effective and very reliable.
Regards Graham
So the detection for controling the drive is in the arm sledge or elsewhere?
It is yes, as it already was in the former models. It’s the disc diametre and therefore speed detection that changed: it's the EP adaptor, once pushed in, that tells the turntable there’s an LP on it. Not quite as fool-proof as before, however...
Jacques
chartz:It’s the disc diametre
no, it's the the weight of a record.
chartz:once pushed in, that tells the turntable there’s an LP on it
No, when it is not pushed in, there will be no record on the plate, so the automatic will stop again after few seconds.
But when pushed in, it can start, and because the black adaptor has the function of a simple scale, the automatic decides to switch to 45 and 17cm size, when a record can be liftet, if not, it will be a 33.
chartz:Not quite as fool-proof as before, however...
That's right, a 25cm will be recognised as a 30cm.
Chris
Still unclear how the drive of the tone arm is detected. From where does it get a signal to move?
The detector arm of the older turntables (4xxx, 6xxx and 8xxx) detects a record on the platter by a photocell and a light-beam directed to the record. The newer turntables detect a record by the adaptor.
The tonearm drive during play is always made by a separate motor and a photocell at the rear of the tonearm, in the flat housing, that moves with the tonearm
The deck doesn’t know how much a record weighs!
It’s just a trick, a simple switch.
The switch indicates what’s on the deck, therefore “selecting” the disc diametre!
chartz:It’s just a trick, a simple switch.
You are funny! Check the manual. And watch what the automatic does, when you put on a 17cm record!
Glad I made you laugh!
Yes, the 45 rpm adapter is the switch. That’s the clever trick.