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 Circuit required for HMV Model 63-54
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 Return to top of page · Post #: 1 · Written at 3:53:17 PM on 6 July 2009.
Alan Foley's Gravatar
 Location: Emerald, VIC
 Member since 6 July 2009
 Member #: 510
 Postcount: 6

I am after a circuit schematic for a 1960's HMV model 6354.
The valve complement is 6M5,6AV6,6AN7,6AX4 and a fourth which I can't read.The tuner has given up although all else works OK;volume etc is still fine.
Thanks,Alan.


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Alan

 
 Return to top of page · Post #: 2 · Written at 9:29:44 PM on 6 July 2009.
Arty41's Gravatar
 Location: Brisbane, QLD
 Member since 18 September 2010
 Member #: 102
 Postcount: 301

Alan,
It could be a 6N8 ? I also think that the 6AX4 maybe a 6X4 ?

Regards
Rudy


 
 Return to top of page · Post #: 3 · Written at 10:38:05 AM on 7 July 2009.
Alan Foley's Gravatar
 Location: Emerald, VIC
 Member since 6 July 2009
 Member #: 510
 Postcount: 6

Thanks Rudy,

You're right it is a 6X4.I will try to obtain a 6N8 which I suspect to be the problem.

Regards,Alan.


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Alan

 
 Return to top of page · Post #: 4 · Written at 11:25:07 PM on 17 July 2009.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5254

HMV tended to use 6BA6 as their RF Amp.

6N8 has nine pins 6BA6 seven pins.

6AX4 Does exist. Its a Half wave Booster diode with an eight pin socket. I would expect to find that in the Horizontal output of a TV.

Need more info there.

Marc


 
 Return to top of page · Post #: 5 · Written at 10:15:15 PM on 19 July 2009.
Arty41's Gravatar
 Location: Brisbane, QLD
 Member since 18 September 2010
 Member #: 102
 Postcount: 301

Marcc,

Alan was talking about a radio not a TV.

Rudy


 
 Return to top of page · Post #: 6 · Written at 5:09:10 PM on 20 July 2009.
Alan Foley's Gravatar
 Location: Emerald, VIC
 Member since 6 July 2009
 Member #: 510
 Postcount: 6

Thanks for your help here.
I think it must be a 6BA6 as it only has 7 pins.

Strange that I switched it on after checking the components (again) and up it came! Intermittents are the worst type of fault.
I hadn't touched it for a week or so; it must have wanted a rest.

Any thoughts on this type if intermittent fault?

Thanks again,Alan.

(Chassis is 63-54 and the model is a Super 5)


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Alan

 
 Return to top of page · Post #: 7 · Written at 10:28:32 PM on 20 July 2009.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5254

A note with 6AX4; This was mentioned in the first posting.

I was pointing out what it was and why it was unlikely to ever be in a radio. viz: its a TV Damper diode, its an International Octagonal and not a minature.

6AN7 is a Triode Hexode. so you would use similar techniques as that of a 6J8 to find out why the tuner has fallen over.

Ie often you can fix a set without specifics as they often follow a similar plot.

One must actually work from the volume control back to the converter to insure that the RF Amp is working & no one has messed up the If transformers by playing with the slugs. Eg do an IF alignment as you start at the last IF. That will save specutation as to where the fault is.

Some times the set has the IF frequency on it. Normally HMV used 457.5 kHz

Check the screen resistor; They used marginal resistances in some sets & they gradually cooked. Some resistors around that time were a bit dicy & in more than a couple of sets, I have ended up turfing the lot.

Marc


 
 Return to top of page · Post #: 8 · Written at 10:20:59 PM on 8 September 2009.
Banjo's Gravatar
 Location: Richmond, NSW
 Member since 1 January 2009
 Member #: 406
 Postcount: 5

Hi Alan,
I have a circuit of an little nipper 65-54 which I think would be pretty close. It has the same valve line up. I repaired one with a crook front end and the fault turned out to be an open circuit coil on the plate of the 6AN7 ( Triode plate that is) Your welcome to a copy of the circuit if you want it

regards,
Banjo


 
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