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 Unknown yellow radio
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 Return to top of page · Post #: 1 · Written at 11:44:21 AM on 29 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

This week's unknown radio has a bright yellow plastic case with a white front.

Valves: 12AN7, 12BA6, 12AQ5, 12X4. The detector is a solid-state black diode.

The volume control is at lower left, and the tuning knob is at upper right, with a circular paper behind the large dial. There's no dial cord.

Any ideas?

Unknown Radio
Unknown Radio
Unknown Radio
Unknown Radio


 
 Return to top of page · Post #: 2 · Written at 9:43:49 PM on 29 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

I have no references with a 12X4 -- that valve appears to have been used mainly in car radios in Oz.


 
 Return to top of page · Post #: 3 · Written at 7:31:28 AM on 30 June 2016.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1133

Titan (KGH) model PRK from 1961.

The detector diode is a OA74.


 
 Return to top of page · Post #: 4 · Written at 8:08:18 AM on 30 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

Ah, thank you. It does have PRK stamped on the back, which was in the photo. Unfortunately those photos haven't been inserted yet.



Edit: I see from the diagram that it is a reflex design.


 
 Return to top of page · Post #: 5 · Written at 9:28:29 AM on 30 June 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4348

AWA Valve manual basically says 12X4 is a 6X4 with a 12.6V only heater: Pin outs same.

Beware of 12AQ5 and 6AQ5. Pins 1 & 7 are G1 and I have seen plenty of disasters from those who think a spare lug on a socket is a tag of convenience and wire to it.

Marc


 
 Return to top of page · Post #: 6 · Written at 10:38:43 PM on 30 June 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6354

Photos uploaded.


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

 
 Return to top of page · Post #: 7 · Written at 11:20:25 PM on 30 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

.Robbert: where are you sourcing this stream of uncommon radios?


 
 Return to top of page · Post #: 8 · Written at 10:34:23 AM on 1 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

Brad: thanks Smile

GTC: I've been collecting for about 15 years but not very much now because cheap radios are harder to come by. Most of the earlier ones came from the Trash & Treasure at Prestons. Others have come from antique stores all over the Southern Highlands, and a few from Queensland when visiting far-away relatives. I have no idea of the rarity, I get it because it's cheap. I'm more likely to get it if it's portable and I don't have one of that type already.


However, my enjoyment comes from getting a broken-down radio going again, rather than from having a house full of radios. I'd happily sell them all off if I could get a very good price.


 
 Return to top of page · Post #: 9 · Written at 12:08:30 PM on 1 July 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6014

Thanks. I'd started to get the impression that you only collected radios that you couldn't immediately identify Smile


 
 Return to top of page · Post #: 10 · Written at 8:56:02 PM on 3 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 508

Ha ha, that sounds like me! I buy them kidding myself I'll sell them, but get attached lol, I just won an Astor BPJ, Identical to this one:-

http://www.ebay.com.au/itm/182185761219

(Which I am currently watching), only Dark blue/grey coloured. I tell my wife I "Won" (an auction) a radio! Luckily for me she lets me get away with it, even thought she has finally seen through my deception!
Unusual ones are definitely more interesting!


 
 Return to top of page · Post #: 11 · Written at 8:57:47 PM on 3 July 2016.
JamieLee's Gravatar
 Location: Clare, SA
 Member since 27 March 2016
 Member #: 1894
 Postcount: 508

That one is amazing, not many capacitors in it!


 
 Return to top of page · Post #: 12 · Written at 9:09:28 PM on 3 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

Yes, fortunately, by the '60s, the old waxed paper caps had been superseded by plastic ones. I don't think I even had to do any work on that radio apart from giving it a clean-up. (oh edit, I added the electro on the output valve.)

As for your Astor, it looks nice. I might possibly have one but not sure.

Edit: Here it is.

Astor BPJ Mantel Radio


 
 Return to top of page · Post #: 13 · Written at 11:58:57 PM on 6 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

Wrong photo Brad...


 
 Return to top of page · Post #: 14 · Written at 9:15:55 AM on 7 July 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6354

Shall fix this arvo. Wink


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

 
 Return to top of page · Post #: 15 · Written at 12:28:24 PM on 10 July 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1381

Is there a problem?


 
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