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 Unknown white radio
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 Return to top of page · Post #: 1 · Written at 11:26:32 AM on 22 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1094

This week's unknown radio is a white one, exactly the same size as my little Airzone. The dial is vertical on the right hand side, and there's 2 knobs underneath.

Valves: 6SA7GT, VR-91, 6BV7, 6X4.

ARTS&P sticker: faded green, #698208

For a 4-valve set it works very well indeed, the 6BV7 is certainly a high gain output stage producing plenty of volume.

I've dug out the CD for my Nokia phone, and from next week I'll be able to take photos.

But for now, can anyone identify this radio from the information given?

Unknown Radio
Unknown Radio


 
 Return to top of page · Post #: 2 · Written at 12:57:51 PM on 22 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5302

Can't find anything in the usual places with that line-up, even when substituting EF50 for VR91.

Closest I come is Titan/KGH who seemed particularly fond of the EF50.


 
 Return to top of page · Post #: 3 · Written at 7:14:50 PM on 22 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1094

It's certainly a mystery radio.

The power cord has an inline power switch (an ancient slide type), but no idea if that was original.

I do need to update the electros as some hum was noticed yesterday.


 
 Return to top of page · Post #: 4 · Written at 10:44:18 PM on 30 June 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5567

These radios were fitted with many different badges. Airzone, Howard, Elizabeth and Aristone were some of the brand names. Some were even made with no name at all. All those I've seen were made after 1950 and are fitted with baseless valves, though I notice yours has a mixture, indicating perhaps being made in 1950 where mixing of types to get rid of old stocks of octal valves was commonplace. The one I own is a no namer.


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

 
 Return to top of page · Post #: 5 · Written at 10:12:48 PM on 4 July 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5567

Here's an Aristone version of this radio:-

http://www.ebay.com.au/itm/302004257346

I should mention that I have also seen this model with a Peal badge.


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

 
 Return to top of page · Post #: 6 · Written at 4:51:51 PM on 8 July 2016.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1306

Definitely KGH. They made several variations on this design depending on what parts they could buy the cheapest!

There was this shop I used to repair radios for when I was a kid. It was at Canley Heights (Western Electrics - he also owned the picture theatre!). He always had one of these new in the shop window. Until the Philips MT3 came along they were the cheapest radio you could buy. Recommended when anyone dropped in a radio for a repair that would have been uneconomical. Cheaper to buy a new one! He sold lots of them. That guy (can't think of his name) was one of the laziest persons I ever met!

As I recall the lineup in the KGH was Converter feeding (I think) regenerative IF/detector via a single IF transformer. No AGC. Yes they had plenty of gain but you had to adjust the volume between stations and whenever the fridge cycled on or off! Just like the Philips MT3. Cheap, nasty but so simple there was nothing to break down!

Now the Philips MT3 is an interesting design. A 3 transistor "battery mantle" radio. OC169/AF116 converter, same transistor type as a reflexed IF and audio amp with the gain control in the RF path, followed by an OC72/OC74 transformer-coupled Class A output stage. The Class A output stage ensured that you were a regular customer for 276P 9 volt batteries, so Philips marketed a battery eliminator (that cost nearly as much as the original radio!) which would fit in place of the battery.

If you've got one of these and it chews batteries, replace the output stage with a BC327. No more thermal runaway and it works just fine biassed a little further down the curve.

Absolutely nothing you can do about the scratchy volume pot. They were like that new, straight out of the box!


 
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