"Demon" transistor radio - UK Vintage Radio Repair and Restoration Discussion Forum

martin.m · 20th Nov 2018, 8:15 pm

This radio was bought untested from the Internet. It was a little grubby but complete with it's leather shoulder strap. I was pleased to find it working, in a fashion, once a 9v battery had been connected. Stations could be tuned in at low volume on LW, but MW reception was non existent. Closer inspection revealed that the ferrite rod aerial was cracked in the middle and the MW winding was open circuit where the rod had contacted a metal support on the chassis. After removing the ferrite rod assembly, I was able to glue it together again and repair the damaged winding without losing any turns.

After reassembly, both wavebands worked but volume was still low. There was a dramatic increase in sound level when I touched one end of the ferrite rod and careful adjustment of the two aerial trimmers restored normal operation on both wavebands. I don't know if the radio was damaged in the post or was like that already. As others have reported on this forum, the sound from this model, although loud and clear, is a little thin and lacking in bass. I may investigate this later and see if an improvement can be made.

The picture shows the radio after it had a light clean up and a little dark furniture polish applied to restore some of the faded colour (tan though it looks dark red in the photo).

Reelman · 20th Nov 2018, 8:38 pm

Good job Martin, nice to see another Eveready set preserved and working. However seems strange but every one of these I’ve seen over the years has a “saggy” speaker cloth showing the outline of the speaker. Can’t think of another set with this “feature”.
Peter

martin.m · 20th Nov 2018, 9:00 pm

Thanks Peter, I didn't notice the saggy speaker cloth but I see what you mean now. I was going to ask in my first post if anyone thought it was worth changing the Plessey electrolytics. Are they troublesome in old age?

Regards
Martin

Sideband · 20th Nov 2018, 9:40 pm

Generally those red/black/yellow Plessy caps are well past their best by now and regarded as change on sight (bit like Hunts waxies). As an example I am currently restoring a Bush TR82 from 1963. The Plessey caps in that were all poor (an ESR meter confirmed it). One was almost O/C, the others were in varying degrees of low capacitance/leaky/high ESR. Changing them produced a marked improvement.

Andrew2 · 20th Nov 2018, 9:58 pm

I've got one just like that but it's a 'Skymaster'. It works but it's a bit rough and I haven't got a 'round tuit' yet. It's been on the shelf for years but as it's a bit of a wreck I keep putting it off!

martin.m · 20th Nov 2018, 10:19 pm

Quote:

Originally Posted by Andrew2

It works but it's a bit rough

Antique dealers call this "Patina". I just clean and tidy up radios as best I can. I don't have the time (or skill) to restore to showroom condition.

Regards
Martin

Paul_RK · 20th Nov 2018, 10:28 pm

Quote:

Originally Posted by Andrew2

I've got one just like that but it's a 'Skymaster'. It works but it's a bit rough and I haven't got a 'round tuit' yet. It's been on the shelf for years but as it's a bit of a wreck I keep putting it off!

If it's just like that it will be a Sky Leader - the Sky Master is a bit later, and smaller, uses a PP7 rather than PP9 and is totally different inside.

Demons usually appear in a different cabinet that's never used for Sky Leaders -

https://www.radiomuseum.org/r/berec_demon.html -

but this form isn't especially scarce.

Paul

crackle · 20th Nov 2018, 11:11 pm

It shouldn't sound "thin", my Sky Leader sounds just about right. Maybe there is one or more electrolytic capacitors which need changing, as suggested by Sideband.
These early pre AF11x transistor radios are normally very reliable and normally work first time, however they can tend to be a bit weak if they have not been used for some years, but they can sometimes improve after an hour of use as the electrolytic capacitors reform.

Mike

FERNSEH · 22nd Nov 2018, 5:00 pm

I recently acquired an Ever-Ready Sky Leader, haven't looked at it yet.

Unlike the Berec Demon, the subject of this topic, my set has a hand wired chassis. Perhaps it's an early production version?

DFWB.

Paul_RK · 22nd Nov 2018, 5:35 pm

Quote:

Originally Posted by FERNSEH

Unlike the Berec Demon, the subject of this topic, my set has a hand wired chassis. Perhaps it's an early production version?

Yes, an earlier example. The Sky Leader / Demon was in production for a few years, I'm not sure which out of the hand-wired and printed circuit versions exists in greater numbers.

Paul

martin.m · 22nd Nov 2018, 11:04 pm

Quote:

Originally Posted by Sideband

Generally those red/black/yellow Plessy caps are well past their best by now and regarded as change on sight.

I changed the three Plessey electrolytics and another Hunts cap (10uF/6v) which connects the wiper of the volume control to the base of the audio driver transistor. The sound is much improved now. Thank you all for your comments and advice. I am enjoying fixing these new-fangled transistor radios.

Regards
Martin

AC/HL · 23rd Nov 2018, 1:11 am

Interesting that radios from an ostensibly export brand appear in such numbers here.

20th Nov 2018, 8:15 pm	#1
martin.m Hexode Join Date: Mar 2018 Location: Bishop Auckland, County Durham, UK. Posts: 373	"Demon" transistor radio This radio was bought untested from the Internet. It was a little grubby but complete with it's leather shoulder strap. I was pleased to find it working, in a fashion, once a 9v battery had been connected. Stations could be tuned in at low volume on LW, but MW reception was non existent. Closer inspection revealed that the ferrite rod aerial was cracked in the middle and the MW winding was open circuit where the rod had contacted a metal support on the chassis. After removing the ferrite rod assembly, I was able to glue it together again and repair the damaged winding without losing any turns. After reassembly, both wavebands worked but volume was still low. There was a dramatic increase in sound level when I touched one end of the ferrite rod and careful adjustment of the two aerial trimmers restored normal operation on both wavebands. I don't know if the radio was damaged in the post or was like that already. As others have reported on this forum, the sound from this model, although loud and clear, is a little thin and lacking in bass. I may investigate this later and see if an improvement can be made. The picture shows the radio after it had a light clean up and a little dark furniture polish applied to restore some of the faded colour (tan though it looks dark red in the photo). Attached Thumbnails __________________ Regards Martin

20th Nov 2018, 8:38 pm	#2
Reelman Octode Join Date: Aug 2008 Location: Rotherham, South Yorkshire, UK. Posts: 1,720	Re: "Demon" transistor radio Good job Martin, nice to see another Eveready set preserved and working. However seems strange but every one of these I’ve seen over the years has a “saggy” speaker cloth showing the outline of the speaker. Can’t think of another set with this “feature”. Peter

20th Nov 2018, 9:00 pm	#3
martin.m Hexode Join Date: Mar 2018 Location: Bishop Auckland, County Durham, UK. Posts: 373	Re: "Demon" transistor radio Thanks Peter, I didn't notice the saggy speaker cloth but I see what you mean now. I was going to ask in my first post if anyone thought it was worth changing the Plessey electrolytics. Are they troublesome in old age? Regards Martin

20th Nov 2018, 9:40 pm	#4
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,567	Re: "Demon" transistor radio Generally those red/black/yellow Plessy caps are well past their best by now and regarded as change on sight (bit like Hunts waxies). As an example I am currently restoring a Bush TR82 from 1963. The Plessey caps in that were all poor (an ESR meter confirmed it). One was almost O/C, the others were in varying degrees of low capacitance/leaky/high ESR. Changing them produced a marked improvement. __________________ There are lots of brilliant keyboard players and then there is Rick Wakeman..... Last edited by Sideband; 20th Nov 2018 at 9:48 pm.

20th Nov 2018, 9:58 pm	#5
Andrew2 Nonode Join Date: Mar 2010 Location: Dukinfield, Cheshire, UK. Posts: 2,036	Re: "Demon" transistor radio I've got one just like that but it's a 'Skymaster'. It works but it's a bit rough and I haven't got a 'round tuit' yet. It's been on the shelf for years but as it's a bit of a wreck I keep putting it off! __________________ Andy G1HBE.

20th Nov 2018, 11:11 pm	#8
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	Re: "Demon" transistor radio It shouldn't sound "thin", my Sky Leader sounds just about right. Maybe there is one or more electrolytic capacitors which need changing, as suggested by Sideband. These early pre AF11x transistor radios are normally very reliable and normally work first time, however they can tend to be a bit weak if they have not been used for some years, but they can sometimes improve after an hour of use as the electrolytic capacitors reform. Mike

22nd Nov 2018, 5:00 pm	#9
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: "Demon" transistor radio I recently acquired an Ever-Ready Sky Leader, haven't looked at it yet. Unlike the Berec Demon, the subject of this topic, my set has a hand wired chassis. Perhaps it's an early production version? DFWB. Attached Thumbnails

23rd Nov 2018, 1:11 am	#12
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: "Demon" transistor radio Interesting that radios from an ostensibly export brand appear in such numbers here.