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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
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11th Apr 2021, 7:45 am | #21 |
Dekatron
Join Date: May 2008
Location: Derby, UK.
Posts: 7,735
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Re: Garrard motor
If it's not a massive difference, could one motor be synchronous and the other a squirrel-cage induction motor (which has to run below synchronous speed)?
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11th Apr 2021, 3:09 pm | #22 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,225
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Re: Garrard motor
These are pictures of the motors.
This one is the replacement motor. These are of the original motor. |
11th Apr 2021, 3:56 pm | #23 |
Tetrode
Join Date: Aug 2010
Location: Mumbai, India.
Posts: 98
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Re: Garrard motor
So my theory gets tossed in the Thames as both the motors are 4 pole, so should turn at identical rpm.
The only suggestion that I can offer now is to connect the replacement motor directly at the wall socket. I have read reply #6 but that did not mention where the "direct to mains" point is, inside the gram cabinet or on the wall. This is the only suggestion that I have at the moment as it would confirm if there is any issue with the replacement motor or the supply point in the gram. Edit : What is the voltage rating stamped on the bottom bearing of the replacement motor? Dual voltage or single voltage? Regards, Anwesh
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Anwesh Last edited by analogadikt; 11th Apr 2021 at 4:07 pm. |
11th Apr 2021, 5:22 pm | #24 |
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Re: Garrard motor
Thanks Anwesh, the motor is stamped 110 200-250V, 40 - 80 Hz he original motor is also dual voltage. I may try another type later tonight.
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17th Apr 2021, 11:08 pm | #25 |
Octode
Join Date: Aug 2006
Location: Stoke-on-Trent, Staffordshire, UK.
Posts: 1,082
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Re: Garrard motor
Garrad motors from the later period ran synchronous by virtue of the fact that they were fitted with a ceramic circular magnet on the rotor . when the motor was required to do some work it then relied on the caged roter
This being the case the stepped pulley would be of a different diameter to the earlier motor Trev |
18th Apr 2021, 9:17 am | #26 | |
Tetrode
Join Date: Aug 2010
Location: Mumbai, India.
Posts: 98
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Re: Garrard motor
Quote:
The original and the replacement motor tried here are pre 1960 pure induction motors. Regards, Anwesh
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Anwesh |
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18th Apr 2021, 12:45 pm | #27 |
Hexode
Join Date: Aug 2014
Location: Wigston, Leicester, UK.
Posts: 351
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Re: Garrard motor
Hi, I've not looked back to check... but wasn't there a thread in the not too distant past where the 2 motor windings were connected out of phase so the mag field wasn't of sufficient strength.....
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20th Apr 2021, 9:55 am | #28 |
Dekatron
Join Date: Mar 2008
Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.)
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Re: Garrard motor
Hi,
I have a Garrard RC80 autochanger. The motor would run fine from cold, but then it began buzzing and getting hot after a time. I found that one of the coils was going dead short when it warmed up. Fortunately, I was able to strip it down and send the two coils off to Ed Dinning to be rewound. He did a splendid job, and it runs lovely now. Thanks Ed! Cheers, Pete.
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20th Apr 2021, 7:36 pm | #29 |
Dekatron
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,195
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Re: Garrard motor
Hi Pete, thanks for the praise. In the particular motor being discussed here the coils had been wound on a jig and the fitted to the motor stack, sdo without trying to make a jig it was a no-no
Ed |
20th Apr 2021, 9:46 pm | #30 | |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
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Re: Garrard motor
Quote:
You were right. I reversed the connections to one of the coils and it started working perfectly. Now to the next horrible one a Beogram 1000. |
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