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 Problems with an HMV Stereophonic electrogram Chassis Type 01
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 Return to top of page · Post #: 1 · Written at 5:15:52 PM on 26 March 2016.
Scotty's Gravatar
 Scotty
 Location: Melbourne, VIC
 Member since 26 December 2010
 Member #: 794
 Postcount: 387

Hi Folks,

I have an HMV Electrogram with chassis type 01. I have replaced all the caps and the O/P transformers are ok. When switched on a get signal briefly then it fades away to barely nothing. Voltages from the bridge rectifier according to the schematic are supposed to be 245V yet I'm reading voltages of 310V on both the bridge and also the O/P transformers.

Not sure if the existing installed bridge rectifier is the problem or where the problem may lay...

Any help appreciated.

Cheers
Scott (frustrated)
 
 Return to top of page · Post #: 2 · Written at 5:59:17 PM on 26 March 2016.
Scotty's Gravatar
 Scotty
 Location: Melbourne, VIC
 Member since 26 December 2010
 Member #: 794
 Postcount: 387

Update, tried replacing the bridge rectifier - no change.
 
 Return to top of page · Post #: 3 · Written at 6:25:38 PM on 26 March 2016.
Tallar Carl's avatar
 Tallar Carl
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2155

Have you checked to see if any resistors are out of tolerance .
 
 Return to top of page · Post #: 4 · Written at 7:01:57 PM on 26 March 2016.
Scotty's Gravatar
 Scotty
 Location: Melbourne, VIC
 Member since 26 December 2010
 Member #: 794
 Postcount: 387

Hi There,

Just did that prior to logging back in here. Found the 220ohm resistor from pin 2 of 6BM8 to ground had gone open. Replaced, and it's up and running again with all voltages around normal.
Cheers
Scott
 
 Return to top of page · Post #: 5 · Written at 7:07:53 PM on 26 March 2016.
Tallar Carl's avatar
 Tallar Carl
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2155

AHH cool
 
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