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 My next restoration a good quality home brand Radio
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 Return to top of page · Post #: 1 · Written at 10:00:20 PM on 11 August 2020.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1575

Got this beautiful set a few weeks back from Scott Beveridge. I love these good old shop radios as I really think they have a place in history. It threw a curveball at me in the form of a very neatly installed mistake ( a 16 μF technico electro was installed backwards ) . This was bringing the dimbulb tester on fairly brightley ( usually doesnt light up at all ) . When I found that and corrected it there was no problem. The only other failure was a oc 0.1 paper cap on the power dropper ( pictured ) . Once I replaced that capacitor the radio came to life.
The valve lineup for this set is 5Y3GT, 6F6, 6J8G, 6U7 and I'm not sure of the other. The dial is gear driven via a friction drive and that needs to be adjusted as it is slipping. I am sure I can fix that but does anyone here have a method that works well.

This Radio is a very strong performer. By the way I have completely recapped it and will tidy up the chassis while waiting for the cabinet that a good friend is restoring for me.

Unknown Radio
Unknown Radio
Unknown Radio
Unknown Radio


 
 Return to top of page · Post #: 2 · Written at 11:00:13 PM on 11 August 2020.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6013

I'm not sure of the other.

Possibly 6G8, 6B6 or 6SQ7. What make and model is the radio?


 
 Return to top of page · Post #: 3 · Written at 11:53:50 PM on 11 August 2020.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1575

GTC no idea. Its a shop radio with no brand.
Actually I'm thinking its a kit radio as there is no ARTS,P sticker


 
 Return to top of page · Post #: 4 · Written at 2:09:31 PM on 12 August 2020.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 941

Re the friction drive, the first thing to do is make sure there is no oil or grease on it. Failing that, disassemble the the drive spindle and turn the drive washers around to present an unworn face to the edge of the disc.

That worked for me. Failing that maybe roughen up the surfaces with fine wet and dry sandpaper, starting at 1200 grade.

The drive washers and disc should not need lubrication; usually the disc is made thick tinplate and the tin acts as a high pressure lubricant. If it is oiled, defeats the friction drive and attracts dust.


 
 Return to top of page · Post #: 5 · Written at 3:49:58 PM on 14 August 2020.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6352

Photos uploaded.


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

 
 Return to top of page · Post #: 6 · Written at 6:41:38 PM on 14 August 2020.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1575

Thankyou sir


 
 Return to top of page · Post #: 7 · Written at 11:28:02 AM on 15 August 2020.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1380

Looks like it says 6B6G, but I've never seen one shaped like that.


 
 Return to top of page · Post #: 8 · Written at 1:06:13 PM on 15 August 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1910

Yes, looks more like an immediate pre-war 1.4v battery valve. It's not, obviously, but there's no reason they couldn't use the same glass.


 
 Return to top of page · Post #: 9 · Written at 10:05:18 PM on 15 August 2020.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1575

Its definitely a 6B6G I have sent a photo to Brad.

6B8G Valve


 
 Return to top of page · Post #: 10 · Written at 8:51:02 PM on 17 August 2020.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6352

Photo uploaded to Post 9.


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

 
 Return to top of page · Post #: 11 · Written at 9:45:52 AM on 18 August 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1910

I think you might just have a very rare toob there...


 
 Return to top of page · Post #: 12 · Written at 10:50:52 AM on 18 August 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 882

Ian, possibly Radiotron were working towards using that outline envelope for all radio valves before they dropped the lot and went Novel.
I dont have any copies of the "Radiotron" newsletter any more that used to announce production things like that.

What I did have was a 6A8 and a X61M mixers in that same outline.
The 6A8 is stuck in some radio somewhere and the X61M envelope actually shattered and was thrown out.

Somebody familiar with Radiotron may know.

Fred.


 
 Return to top of page · Post #: 13 · Written at 11:21:53 AM on 18 August 2020.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1133

I know that AWV and Miniwatt branded 6B6G valves were still being locally manufactured for replacement purposes well into the 1960's. I think have a Miniwatt example somewhere & it still has the "G" shape envelope.

It is possible (following Freds lead) that it may be a rebranded Marconi/Osram type. After the war AWV marketed a line of Radiotron branded UK made Marconi/Osram types.

Marconi/Osram did manufacture a DH76 triode/twin diode which has a "GT" shape envelope. The DH76 however has a 13 volt heater.


 
 Return to top of page · Post #: 14 · Written at 2:45:34 PM on 18 August 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1910

But then there was the 6AR7 developed by AWV. And AWV were making 1.4v octal battery valves at the time. It would make sense....


 
 Return to top of page · Post #: 15 · Written at 3:25:55 PM on 18 August 2020.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1133

Perhaps Carl could carefully remove this unusual 6B6G from the chassis and see if there is any tell-tale markings that may identify its origin.


 
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