Unidentified French Radio - UK Vintage Radio Repair and Restoration Discussion Forum

poppydog · 25th May 2019, 3:57 pm

Thought I would post this pic of the component layout on this unusual French radio as it might be of some interest. Also could anyone please tell me what they think the 2 red coils from the battery up to the on/off switch do on this radio please? I still haven’t managed to source a sheet for this or a makers name yet, see this thread:

https://www.vintage-radio.net/forum/...d.php?t=142574

Regards
Poppydog

ms660 · 25th May 2019, 6:14 pm

The coils look like suppression chokes, the radio could be similar to this one with a General-Radio logo on it, it's French made so far as I can make out:

https://www.doctsf.com/document-publ...4#lg=1&slide=0

Lawrence.

TrevorG3VLF · 25th May 2019, 9:07 pm

Are the transistors tin whiskered AF117?
Does the set work? Try 6V or 9V.

poppydog · 26th May 2019, 10:49 am

Thanks for finding that info Lawrence

, with regards to the coils, I haven't seen anything like this before on any of the other transistor radios I have here. I will put couple more pics up later.

Regards Poppydog

'LIVEWIRE?' · 26th May 2019, 11:03 am

If, as the ad, in the link in Lawrence's post suggests, it's a car/portable radio (En plein air, en voiture, etc.), those could indeed be suppressor (filter) chokes designed to minimise interference when the radio is connected, as most car/portables were, to the vehicle's battery when fitted in a car. Most C/P radios came with an installation kit for this purpose.

poppydog · 2nd Jun 2019, 5:06 pm

Some more pics of this chassis below. The chassis is stainless steel with an array of good quality components, Philips electrolytics, what looks like SFT type transistors in the audio side of things and the rest are af117/118, all these transistors are held steady in the chassis by wax

.

I have had to replace 3 electrolytics as they were not good, and have had to tap the af117 the 2nd IF a few times to get things working, if I have any more trouble with the af117s I will have to think about replacing them. It sounds very good through the excellent quality Audax speaker but must have cost an absolute fortune to produce though.

https://www.doctsf.com/general-radio...812819a794c89f

Regards
Poppydog

Mike. Watterson · 3rd Jun 2019, 3:04 pm

Plated steel. I don't remember any stainless steel that would solder. It's for same reason it doesn't rust.
The chokes may be interference filters for car supply.

Any Russian PNP Germanium part with 60MHz ft will do. Much cheaper than AF127. Some AF117 batches (and similar OC17x series) are OK. I think the problem was too much tin on the inside of the can.

poppydog · 3rd Jun 2019, 3:10 pm

You may be right, it may not be stainless, but it is very rigid unlike mild steel. I will check again later and let you know.
poppydog

poppydog · 3rd Jun 2019, 7:23 pm

Yes you are right Mike. Watterson, its mild steel

,speaker magnet grips it tight. Very surprised other elite members missed that one

Regards Poppydog

Mike. Watterson · 3rd Jun 2019, 9:21 pm

There ARE some varieties of "stainless steel" that are "magnetic". There could even be a kind that can be soldered, but that seems as unlikely as soldering aluminium (which is only nearly impossible!).

It's not important.

It's strange to see a point to point wired transistor chassis, though Ever Ready, Bush and others had them even though years earlier there where PCB battery valve radios, including some by Ever Ready. You needed automated component insertion and wave soldering to get a big cost saving. That meant big volumes too.

Irrelevant but might be interesting:
https://www.kimballphysics.com/magne...ainless-steels
https://www.scientificamerican.com/a...on/?redirect=1
https://www.bssa.org.uk/faq.php?id=24

You CAN solder Aluminium or Stainless Steel. But special fluxes and techniques are needed and the result won't look like your photos.
https://www.bssa.org.uk/topics.php?article=150
https://superiorflux.com/soldering-s...omponents-pcb/

Still, it looks more like plated steel than stainless in the photo. Also the cost of punching and drilling stainless steel is more expensive than ordinary steel, which can be plated after fabrication and is a cheaper material. Rivets and tags are more common with aluminium and stainless steel chassis.

poppydog · 4th Jun 2019, 8:38 am

Thanks for the links Mike, as you've said its not important

, I still think it would have cost a fortune to produce.
With regards to the af117, I would have to get something that looks very similar as I don't want to alter the way it looks, also is it me or do those leadouts on the af117 in the 1st IF look a mile long, much longer than usual??
poppydog

TrevorG3VLF · 4th Jun 2019, 9:28 am

Long leads to Ge transistors were to keep the heating of the transistor to low levels. I have never had problems with shorter leads even without pliars as a heat sink.

You could get a modern transistor inside an AF117 case and the lack of a screen lead would not be noticed. The case could have a lead attached to it, it is tin plated so will solder easily.

poppydog · 7th Jun 2019, 11:07 am

Thanks for the advice TrevorGV3LF, if I have any more trouble I will look to change them, it's only a couple minutes work to remove chassis from case.
Regards Poppydog

25th May 2019, 3:57 pm	#1
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Unidentified French Radio Thought I would post this pic of the component layout on this unusual French radio as it might be of some interest. Also could anyone please tell me what they think the 2 red coils from the battery up to the on/off switch do on this radio please? I still haven’t managed to source a sheet for this or a makers name yet, see this thread: https://www.vintage-radio.net/forum/...d.php?t=142574 Regards Poppydog Attached Thumbnails

25th May 2019, 6:14 pm	#2
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Unidentified French Radio The coils look like suppression chokes, the radio could be similar to this one with a General-Radio logo on it, it's French made so far as I can make out: https://www.doctsf.com/document-publ...4#lg=1&slide=0 Lawrence.

25th May 2019, 9:07 pm	#3
TrevorG3VLF Rest in Peace Join Date: Apr 2011 Location: Matlock, Derbyshire, UK. Posts: 1,378	Re: Unidentified French Radio Are the transistors tin whiskered AF117? Does the set work? Try 6V or 9V.

26th May 2019, 10:49 am	#4
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio Thanks for finding that info Lawrence, with regards to the coils, I haven't seen anything like this before on any of the other transistor radios I have here. I will put couple more pics up later. Regards Poppydog

26th May 2019, 11:03 am	#5
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: Unidentified French Radio If, as the ad, in the link in Lawrence's post suggests, it's a car/portable radio (En plein air, en voiture, etc.), those could indeed be suppressor (filter) chokes designed to minimise interference when the radio is connected, as most car/portables were, to the vehicle's battery when fitted in a car. Most C/P radios came with an installation kit for this purpose.

2nd Jun 2019, 5:06 pm	#6
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio Some more pics of this chassis below. The chassis is stainless steel with an array of good quality components, Philips electrolytics, what looks like SFT type transistors in the audio side of things and the rest are af117/118, all these transistors are held steady in the chassis by wax . I have had to replace 3 electrolytics as they were not good, and have had to tap the af117 the 2nd IF a few times to get things working, if I have any more trouble with the af117s I will have to think about replacing them. It sounds very good through the excellent quality Audax speaker but must have cost an absolute fortune to produce though. https://www.doctsf.com/general-radio...812819a794c89f Regards Poppydog Attached Thumbnails

3rd Jun 2019, 3:04 pm	#7
Mike. Watterson Heptode Join Date: Dec 2014 Location: Limerick, Ireland. Posts: 901	Re: Unidentified French Radio Plated steel. I don't remember any stainless steel that would solder. It's for same reason it doesn't rust. The chokes may be interference filters for car supply. Any Russian PNP Germanium part with 60MHz ft will do. Much cheaper than AF127. Some AF117 batches (and similar OC17x series) are OK. I think the problem was too much tin on the inside of the can.

3rd Jun 2019, 3:10 pm	#8
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio You may be right, it may not be stainless, but it is very rigid unlike mild steel. I will check again later and let you know. poppydog

3rd Jun 2019, 7:23 pm	#9
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio Yes you are right Mike. Watterson, its mild steel,speaker magnet grips it tight. Very surprised other elite members missed that one Regards Poppydog

3rd Jun 2019, 9:21 pm	#10
Mike. Watterson Heptode Join Date: Dec 2014 Location: Limerick, Ireland. Posts: 901	Re: Unidentified French Radio There ARE some varieties of "stainless steel" that are "magnetic". There could even be a kind that can be soldered, but that seems as unlikely as soldering aluminium (which is only nearly impossible!). It's not important. It's strange to see a point to point wired transistor chassis, though Ever Ready, Bush and others had them even though years earlier there where PCB battery valve radios, including some by Ever Ready. You needed automated component insertion and wave soldering to get a big cost saving. That meant big volumes too. Irrelevant but might be interesting: https://www.kimballphysics.com/magne...ainless-steels https://www.scientificamerican.com/a...on/?redirect=1 https://www.bssa.org.uk/faq.php?id=24 You CAN solder Aluminium or Stainless Steel. But special fluxes and techniques are needed and the result won't look like your photos. https://www.bssa.org.uk/topics.php?article=150 https://superiorflux.com/soldering-s...omponents-pcb/ Still, it looks more like plated steel than stainless in the photo. Also the cost of punching and drilling stainless steel is more expensive than ordinary steel, which can be plated after fabrication and is a cheaper material. Rivets and tags are more common with aluminium and stainless steel chassis. Last edited by Mike. Watterson; 3rd Jun 2019 at 9:33 pm. Reason: Magnetic Stainless

4th Jun 2019, 8:38 am	#11
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio Thanks for the links Mike, as you've said its not important, I still think it would have cost a fortune to produce. With regards to the af117, I would have to get something that looks very similar as I don't want to alter the way it looks, also is it me or do those leadouts on the af117 in the 1st IF look a mile long, much longer than usual?? poppydog

4th Jun 2019, 9:28 am	#12
TrevorG3VLF Rest in Peace Join Date: Apr 2011 Location: Matlock, Derbyshire, UK. Posts: 1,378	Re: Unidentified French Radio Long leads to Ge transistors were to keep the heating of the transistor to low levels. I have never had problems with shorter leads even without pliars as a heat sink. You could get a modern transistor inside an AF117 case and the lack of a screen lead would not be noticed. The case could have a lead attached to it, it is tin plated so will solder easily.

7th Jun 2019, 11:07 am	#13
poppydog Banned Join Date: Oct 2015 Location: Cornwall, UK. Posts: 849	Re: Unidentified French Radio Thanks for the advice TrevorGV3LF, if I have any more trouble I will look to change them, it's only a couple minutes work to remove chassis from case. Regards Poppydog