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 The little general that maybe never was
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 Return to top of page · Post #: 1 · Written at 3:54:24 PM on 27 July 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 659

Hello all I have this basket case from Tony H`s collection . I might end up keeping it. I thought it was going to be a little general the one that was brought out with the short wave which I do not have a circuit for anyway not that it worries me because it will end up as MW band only. There is not much left of it with bits hacked out and fallen off. It will require a complete strip down. I have a couple of chassis Tony gave me to rat bits off so I am hoping I might be able to make something of it just for the chalange . I can't figure out the valves I expected to see a 6V6 in there the rectifier is a good old standard 80 one valve is missing from the physical location I thought it would be the osc mixer the valves I have are 80`6J8`and what looks like by the writing EBF28 this does not exist so maybe the printing is smudged and it could be an EBF2G GT. It has gold metallic paint and a top cap which connects to the IF transformer so is it EBF2G Duo-Diode remote cutoff Pentode acting as the detector and audio out. The wiring is in ruins it must have had an electrodynamic speaker originally because there is no sign of a choke. I guess the wave change switch assembly contains the MW aerial coil , not sure how I can tell what is what maybe easier to get one from the junked chassis. I will ask Brad if he can upload some pictures I used a tripod this time on time delay so you may even be able to see what the pictures contain.
Regards Jimb

Little General Valve Radio
Little General Valve Radio
Little General Valve Radio
Little General Valve Radio


 
 Return to top of page · Post #: 2 · Written at 7:18:19 PM on 27 July 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 882

Look forward to pictures Jimb.

Fred.


 
 Return to top of page · Post #: 3 · Written at 8:22:29 PM on 27 July 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 659

Let's hope they are better than my last effort Fred.


 
 Return to top of page · Post #: 4 · Written at 8:44:09 PM on 27 July 2020.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6349

Photos uploaded.


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

 
 Return to top of page · Post #: 5 · Written at 8:47:45 PM on 27 July 2020.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6012

I have one that's very similar externally. It's in my compactus -- where the project queue resides.


 
 Return to top of page · Post #: 6 · Written at 9:42:07 PM on 27 July 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 659

Thank you Brad for uploading the photos.
GTC. maybe this would be better off in in a compactus (crusher) it is vertually scrap.However it does not all have to be done by tomorrow it can be a longer term project. I just need to keep busy. I received the speaker cloth today for the Astor Mickey HPM so that will jump the queue.


 
 Return to top of page · Post #: 7 · Written at 1:19:26 AM on 28 July 2020.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1380

Not many capacitors or resistors there, did someone remove them all?

All I can suggest is to make a schematic of what's left, rip it all out and start over.

Not even sure what is supposed to be the output valve, I assume it's the missing one.


 
 Return to top of page · Post #: 8 · Written at 9:10:49 AM on 28 July 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 659

If I do anything with it I will turn it into a little general. I have already done that to another I had in not quite so bad condition.
It must have been ratted for bits because there is hardly anything left.


 
 Return to top of page · Post #: 9 · Written at 9:23:22 AM on 28 July 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4344

I would think it was a good idea to list what valves are in it and to reverse engineer it & then we go from there. It looks like parts from Jack & Jill; Fred & Bill.

The empty socket looks like a transformer on speaker. EBF2G was used by HMV around 661 as WD had scarpered off with the 6B8's. metalisation pin should be grounded wiring will be different than 6B8.

If it was a "Little General" a quick look says the poltergeist, has beaten me to the folder with their circuits in it.

I normally draw the tubes, transformers, sockets etc. in position then play join the dots & get a layout diagram, then translate it into the circuit as is; even if its wired wrongly.

One does not touch the set until such time as there is a circuit and its been checked. If you ablolutely have to remove a wire to check a coil, mark it & put it back where you found it.

Draw the tube elements & number for clarity: I use an AutoCAD in which I have the std diagrams of tubes etc. to cut / import into the draft layout.

Marc


 
 Return to top of page · Post #: 10 · Written at 10:38:59 AM on 28 July 2020.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1133

Found it!

It is the Little General for 1946 as described in Radio & Hobbies in Australia, January 1946.

Valve line-up: 6J8G, EBF2G, 6V6GT & 5Y3G.

All parts including the chassis & case were available at radio supplies stores.


 
 Return to top of page · Post #: 11 · Written at 11:42:42 AM on 28 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1905

That looks like an Aegis dual wave switch and coil assembly. It would be good to keep it.

The design was known as a "short superhet", i.e. missing the 1st audio stage. Might be worth reflexing the EBF2G, it looks like it could be a candidate.

Here is the data for the side contact (non-G) version, which includes an application circuit (how's your German?)

https://frank.pocnet.net/sheets/005/e/EBF2.pdf


 
 Return to top of page · Post #: 12 · Written at 11:54:07 AM on 28 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1905

That G - bottle 80 is threatening to cook the mains transformer. I think I have a "GT" style 80 which would be better - you'd be welcome to it. Or you could use a 5Y3GT.


 
 Return to top of page · Post #: 13 · Written at 12:26:01 PM on 28 July 2020.
Gandhn's Gravatar
 Location: Windella, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 343

The R&H article found by MonochromeTV gives the circuit and full construction information, so a strip down of the remaining wiring and a complete rebuild would be quite feasible. The article even confirms the band change module connections.

The result would be an uncommon dual wave Little General and a worthy addition to any collection.

Good luck.

Harold


 
 Return to top of page · Post #: 14 · Written at 7:15:34 PM on 28 July 2020.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6012

.Jimb: I've emailed you that article.


 
 Return to top of page · Post #: 15 · Written at 8:49:04 PM on 28 July 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 659

Thank you all for your comments.
It will be a project for the future my AWA 191 console reciever I have owned for 52 years chucked a wobbly this morning very low almost non existent audio. It is the push button version and it is a pig to work on because of the push button rubbish covering over the top of a large number of components. Plus the speaker is still in the cabinet and it looks like the retaining nuts have rusted into position.
I did major surgery on it about 12 years ago . About 2 years ago a couple of resistors failed and has been working very well after that.
I have not had time to look at it yet apart from noting the grid bias resistor on the 6F6 has gone out of spec should be 500k now a bit over 700k. I do not think that is the end of the story.
Regards Jimb


 
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