Yet another radio set! - UK Vintage Radio Repair and Restoration Discussion Forum

Tractorfan · 26th Mar 2018, 8:29 pm

Hi,
Today I was given a rather tidy German spec. 'Blaupunkt Granada Stereo' radio.
It's AM/FM with the option of fitting a stereo decoder. After a check over and a clean of the switches and pots (although they hardly crackled), it works well and sounds great! I reset the mains selector from 220v to 240v to give it an easier life.
Oddly, it has two tuning 'eyes'; one is the usual EM87, and t'other is an EAM86 which only lights on FM, but does nothing else. Maybe it's a stereo indicator when the optional decoder is fitted. I noticed that the phosphor was 'scorched' and think that may be because it's been powered up, but not active since 1970-ish.
Does anyone know how reliable the coupling (that) caps are in this set?
Cheers, Pete.
PS, I'm not sure, but the EAM86 appeared to have two very small heaters. This may have been a reflection, but I'll have to have a closer look.

vinrads · 2nd Apr 2018, 5:05 pm

What a smashing set , with Grundig's I think I would change all the paper capacitors ,Mick.

Sideband · 2nd Apr 2018, 9:31 pm

Interesting valve. It also has an internal diode. Looks like it has two heaters. Info here

ms660 · 2nd Apr 2018, 9:51 pm

The diode in that valve in this receiver is for providing the target control voltage when a 19kHz pilot tone is received and doubled to 38kHz.

https://www.vintage-radio.net/forum/....php?p=1030025

Lawrence.

26th Mar 2018, 8:29 pm	#1
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,183	Yet another radio set! Hi, Today I was given a rather tidy German spec. 'Blaupunkt Granada Stereo' radio. It's AM/FM with the option of fitting a stereo decoder. After a check over and a clean of the switches and pots (although they hardly crackled), it works well and sounds great! I reset the mains selector from 220v to 240v to give it an easier life. Oddly, it has two tuning 'eyes'; one is the usual EM87, and t'other is an EAM86 which only lights on FM, but does nothing else. Maybe it's a stereo indicator when the optional decoder is fitted. I noticed that the phosphor was 'scorched' and think that may be because it's been powered up, but not active since 1970-ish. Does anyone know how reliable the coupling (that) caps are in this set? Cheers, Pete. PS, I'm not sure, but the EAM86 appeared to have two very small heaters. This may have been a reflection, but I'll have to have a closer look. Attached Thumbnails __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..." Last edited by Tractorfan; 26th Mar 2018 at 8:35 pm. Reason: Added a PS.

2nd Apr 2018, 5:05 pm	#2
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Yet another radio set! What a smashing set , with Grundig's I think I would change all the paper capacitors ,Mick.

2nd Apr 2018, 9:31 pm	#3
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,572	Re: Yet another radio set! Interesting valve. It also has an internal diode. Looks like it has two heaters. Info here __________________ There are lots of brilliant keyboard players and then there is Rick Wakeman.....

2nd Apr 2018, 9:51 pm	#4
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Yet another radio set! The diode in that valve in this receiver is for providing the target control voltage when a 19kHz pilot tone is received and doubled to 38kHz. https://www.vintage-radio.net/forum/....php?p=1030025 Lawrence.