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 STC radio information
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 Return to top of page · Post #: 16 · Written at 2:10:00 AM on 24 June 2016.
Viccadillac's Gravatar
 Location: Perth, WA
 Member since 7 May 2012
 Member #: 1140
 Postcount: 152

Ok Here Goes the info.

I can't find any info among my papers on this one. The unit has since long gone but on my spare chassis the valve line up is as follows.

Chassis number G62259, date on o/p transformer 1957, model number on sticker is faded but made out 64.

6BA6, 6BA7, 6N8, 6L6GA, 12AX7, 5Z4.

On photos I have both chassis have the same valve line up .

Found the model number STC 6461 , Kevin Chant has the file

http://www.kevinchant.com/uploads/7/1/0/8/7108231/6461.pdf


Cheers
Vic

STC Radio Chassis


 
 Return to top of page · Post #: 17 · Written at 9:49:17 AM on 24 June 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4333

No wonder they used the 12AX7. The OP of this is reminds me of the R53B HMV I have here at the moment. It uses the similar #807 in a single ended output.

Changer looks to be a similar brand to HMV & its a mechanical abomination. It will likely need servicing if you get an original.

Marc


 
 Return to top of page · Post #: 18 · Written at 9:55:13 AM on 24 June 2016.
GBR's Gravatar
 GBR
 Location: Gladstone, QLD
 Member since 15 May 2016
 Member #: 1925
 Postcount: 30

Thank you very much, you guys are awesome. I will have to find more challenges for you all Smile


 
 Return to top of page · Post #: 19 · Written at 12:32:18 PM on 24 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6002

Interestingly, although the schematic shows the converter to be a 6BA7, the attached notes calling it model A6461 give it as 12AH8 (a valve used by a number of STC models in the 1950s).


 
 Return to top of page · Post #: 20 · Written at 2:57:11 PM on 24 June 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4333

One would have to pay serious attention to the wiring of the socket. Both are 9pin & the temptation would be to use 12AH8 Triode Heptode in a shortwave set rather than a Pentagrid. They are absolutely not pin interchangeable, that's why the need to check the socket.

Marc


 
 Return to top of page · Post #: 21 · Written at 4:20:48 PM on 24 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1378

Yes, the 6BA7 has no pin-compatible equivalent. Also (beside the point), I've never seen one.

However the 12AH8 is a familiar valve among the fragile plastic STC's, along with 6CH6.

The OP mentioned 6CA7, I assume he meant 6BA7.


 
 Return to top of page · Post #: 22 · Written at 5:09:08 PM on 24 June 2016.
GBR's Gravatar
 GBR
 Location: Gladstone, QLD
 Member since 15 May 2016
 Member #: 1925
 Postcount: 30

Yes sorry 6BA7


 
 Return to top of page · Post #: 23 · Written at 9:25:07 PM on 24 June 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6340

Photo uploaded to two posts.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 24 · Written at 10:46:27 PM on 24 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6002

.Vic: What's that clamp around the base of the octal valve?


 
 Return to top of page · Post #: 25 · Written at 4:51:17 PM on 25 June 2016.
GBR's Gravatar
 GBR
 Location: Gladstone, QLD
 Member since 15 May 2016
 Member #: 1925
 Postcount: 30

That's it exactly Vic,

Although mine is missing the output. rectifier and preamp valves.

Oh, and mine looks like it has had a much harder life Smile

In fact, I am hoping that I wont upset too many here, when I say I think I will just end up re-purposing the amplifier components.


 
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