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Meat Plow[_5_] Meat Plow[_5_] is offline
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Default Rega RB300 turntable...

On Tue, 18 May 2010 10:40:49 +0100, N_Cook wrote:

Arfa Daily wrote in message
...

"DaveD" wrote in message
...
Arfa Daily wrote:
"Geo" wrote in message
...
On Mon, 17 May 2010 17:28:20 +0100, "Arfa Daily"

wrote:


It definitely says "Rega Planar 3" at the top front right corner,
although
it's hard to see as the letters are just black 'shininess' within
the black
satin anodised finish of the cabinet. Underneath, directly under
the motor,
is a cover secured by two screws, When this is removed, the motor
and

a
small PCB are revealed. The PCB has just two components on it -
the burnt up
R, which is a large 'film' type, I guess something like about 5mm
diameter
and 20mm or so long, and the 0.22u 400v cap, which is one of those
green MKT
monobloc types. These two components are mounted 'on the slant' on

the
board. The mains comes in, and the neutral is joined immediately
to

two
grey
wires from the motor. The live leaves the board again on a white
wire which
goes to the on / off switch at the front top left of the deck.
Live returns
to the board on another white, and goes to the motor red lead via
the burnt
up resistor. The cap is between the red lead and the remaining
blue lead.
Doesn't sound much like the example that you're looking at, eh ?
How about this version from mine - looks like a 15k 5% (old 2-5w
carbon?)
http://www.8zero.co.uk/planar.jpg


--
Geo

Yes, that's closer - although still not quite the same
configuration. It's actually a different motor in yours, but the
supply still goes to the red via the resistor, and the cap still
appears to be between red

and
blue, and the same value, although a different type. Based on that,
I think I'm going to start with 15k now, and see if the motor runs,
and

if
it does, if it has enough torque to drive the platter.

Thanks very much for taking the trouble to post me the piccy.
Appreciated.

Arfa
Hi Arfa
Further info. The data I supplied earlier was from the Planar 3
upgrade motor assembly.
I have just pulled out the old motor and PCB. It has only 2
components on it.
1 x 220nf 250v ac X rated cap manufactured by Rifa. 1 x 12k 2-3 watt
resistor, 8.5mm dia x 25mm long. The resistor is a mid brown body
colour and the bands are quite hard to read but measurement confirms
12k 5% (as in brown red orange gold) The brown and orange are hard to
differentiate The motor is a Philips 110v 50hz 250 rpm (12NC
990411131613) date of manufacture 1985 with the same colour leads I
would suggest going with what you have in the 12 - 15k ~ 5 watt
resistor. Check that the voltage to the motor is in the region of
110v under load and it should be good to go Cheers
DaveD


Many thanks Dave. That's it exactly. I just had a look, and I haven't
got

a
high power 12 or 15k in stock, but I have got some 47k 2 watt film
resistors, so to save time and get the item back to the customer (he's
already put up with me being away on holiday for 2 weeks !), I'm going
to put three of those in parallel as there's plenty of room. Thanks
again,

all.

Arfa



Is there a fuseable resistor function to the original ? ie 2 watts of
dissipation from stalled motor and the R blows rather than the motor.
Would not some 1/2 watt resistors together giving 12K be better?


He has a point.