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 Unknown out-of-the-console radio #1
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 Return to top of page · Post #: 1 · Written at 11:47:37 AM on 15 June 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1303

Turns out I have a number of unknown sets. I will present one per week until they are all done.

This one is my first ever valve set. It was given to me by a teacher back when I was in school in the 70s.

It obviously had come out of a console, but all I got was the radio, and a loose oval speaker (definitely not original).

Knobs (left to right): Band Change (MW/Phono/SW), Volume, Tuning, Bass, Treble/Power.

Valves: 6BH5, 6AN7, 6BH5, 6AL5, EF86, 12AU7, 6M5, 6M5, EM84, EZ80.

The dial glass was huge, covering the entire front, except where the knobs are. Unfortunately accidents do happen, and the glass got broken, then eventually thrown out. So now we have an ugly dark purple front with some station markings written on in black. The original glass had the stations of each state marked on (including 9PA). It also had an identification:

"Rangemaster 10-valve Mark V Quality Radio"

At some stage (before I got it), the speaker transformer had been replaced.

I did a lots of experiments on the radio. The old components were replaced. Later I decided to convert the output to ultra-linear by adapting an EA article. So the 12AU7 became a 12AX7, the EZ80 (by now a 6V4) became a 6CA4, and the 6M5s became 6BQ5s. The speaker transformer had the extra tappings which had been cut short. I soldered wires to these, and success was mine. The radio has excellent sound.

So, in the end I have an unknown radio that works very well, but looks horrible.

Does anyone know what brand / model it is? Although I drew a schematic back in the day, it would be helpful to have the real thing.

Unknown Radio
Unknown Radio
Unknown Radio


 
 Return to top of page · Post #: 2 · Written at 3:10:04 PM on 15 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

Valves: 6BH5, 6AN7, 6BH5, 6AL5, EF86, 12AU7, 6M5, 6M5, EM84, EZ80.

Can't find anything like that line-up in the usual places.


 
 Return to top of page · Post #: 3 · Written at 4:32:33 PM on 15 June 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4178

EF86 should cross reference to 6BK8 Low noise sharp cut of Audio Pentode. EM84 Tuning indicator with Triode 6FG6; EZ80 is 6V4.

12AU7 looks a lot like paraphase push pull & its the splitter. 6AN7 Frequency converter; separate diode detector 6AL5 so it may have delayed AGC; 6BH5 is an RF Pentode. So the order is pretty obvious. Naturally 6M5's are the PP output.

HMV were using "Rangemaster" in the sixties. A lot of their chasses had a roll cage on them enabling easy servicing when upside down.

Marc


 
 Return to top of page · Post #: 4 · Written at 5:22:45 PM on 15 June 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

HMV were using "Rangemaster" in the sixties

There are a few references to HMV transistor set and TV called Rangemaster, but nothing out there on valve radio sets with that name, which I find odd given HMV's popularity.


 
 Return to top of page · Post #: 5 · Written at 10:05:09 PM on 15 June 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4178

Photo might be useful? STC had a habit of using some seemingly odd ball valves that others did not use commonly. Part numbers may be helpful if there are any.

Marc


 
 Return to top of page · Post #: 6 · Written at 10:53:24 PM on 30 June 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6174

Photos uploaded.


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

 
 Return to top of page · Post #: 7 · Written at 8:04:38 PM on 10 July 2016.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1790

This radio was made by Classic Radio in Sydney. Early 1960s.


 
 Return to top of page · Post #: 8 · Written at 9:46:02 PM on 10 July 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

If it's a Classic Radio production, then it's likely based on an RT&H project.


 
 Return to top of page · Post #: 9 · Written at 8:34:02 AM on 13 November 2016.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1098

I revisited this thread last night & I think both Ian Robertson & GTC could be correct.

Going through a 1958 RTV&H I found an ad for a 10 valve radiogram chassis by Classic. It didn't give any details such as a valve line-up.

In the September 1955 issue there is a project for a 8 valve radiogram. The valve line-up is 6BH5, 6AN7, 6N8, EF86,12AX7, 6BQ5 X 2 & 5Y3GT. Apart from not having a magic-eye, note that the pentode section in a 6N8 is close to a 6BH5, & a 6AL5 can take care of the diodes.

The previous August issue shows an ultra-linear version of the amplifier.


 
 Return to top of page · Post #: 10 · Written at 12:01:05 PM on 13 November 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1303

I turned it on the other day and now it makes a very loud crackling noise on the AM band, with the magic-eye display jumping up and down like crazy. Even when switched to the gram position, the crackling is still faintly audible.

I suppose a repair will be needed....


 
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