Stereo Console Bergamo GB (Grundig) - TX cooked - UK Vintage Radio Repair and Restoration Discussion Forum

Al (astral highway) · 31st Aug 2017, 2:20 pm

Hi folks,

This is a really lovely set - certainly in terms of the build quality of the electronics, from what I can see -not so fussed about the cabinet - but is currently kaput with a blown main transformer. The secondary is cooked and bubbles even off load, there is another winding, whose voltage I don't know yet - likely the the heaters. ECC85, ECH81, EAF801, ECC83 and wonderful ELL80 - a double output-pentode in one envelope for push-pull use - are all intact.

Anyone can source a cct diagram for me please? I think in view of the age of the thing, the bridge rectifier was probably SC for some reason. I will check later. There are no obvious catastrophic failures of any component.

My goal is to find out what the other secondary winding is first, before hunting for a replacement transformer.

BUt if anyone has prior experience with this beauty, be interested to know what aere the possible fault conditions leading to a cooked main transformer.

Thank you

Michael Maurice · 31st Aug 2017, 2:37 pm

Have you tried Radiomuseum?

You would be better to get the original TX rewound. Mike Barker or Ed Dining can sort that for you.

Reelman · 31st Aug 2017, 2:42 pm

Bergamo was a generic name for a range of radiograms made by Grundig over a number of years. The last ones were transistor.

Could this be yours....
http://www.radiomuseum.org/r/grundig..._st_cs200.html

If it is, very nice. Have a very soft spot for Grundig audio kit. Used to love to go to the showroom in Orchard Street, just off Oxford Street.

Good luck with it,

Peter

Al (astral highway) · 31st Aug 2017, 6:59 pm

Hey, Peter, that looks like the one! Thank you !

Amazing quality!

Maurice , good idea. It first I'd like to establish if there is any fault downstream before making such an investment ...

Ed_Dinning · 31st Aug 2017, 9:07 pm

Hi Al, always pays to use an HT fuse on these sets, either in the feed to the bridge or in the CT if it is full wave. It's a mod I do on most sets .
Transformer should rewind OK.

Ed

Al (astral highway) · 31st Aug 2017, 9:58 pm

Cheers, Ed!good advice !! I'll PM you re the rewind, if it looks like there are no other faults downstream ...

31st Aug 2017, 2:20 pm	#1
Al (astral highway) Dekatron Join Date: Nov 2006 Location: London, UK. Posts: 3,496	Stereo Console Bergamo GB (Grundig) - TX cooked Hi folks, This is a really lovely set - certainly in terms of the build quality of the electronics, from what I can see -not so fussed about the cabinet - but is currently kaput with a blown main transformer. The secondary is cooked and bubbles even off load, there is another winding, whose voltage I don't know yet - likely the the heaters. ECC85, ECH81, EAF801, ECC83 and wonderful ELL80 - a double output-pentode in one envelope for push-pull use - are all intact. Anyone can source a cct diagram for me please? I think in view of the age of the thing, the bridge rectifier was probably SC for some reason. I will check later. There are no obvious catastrophic failures of any component. My goal is to find out what the other secondary winding is first, before hunting for a replacement transformer. BUt if anyone has prior experience with this beauty, be interested to know what aere the possible fault conditions leading to a cooked main transformer. Thank you __________________ Al

31st Aug 2017, 2:37 pm	#2
Michael Maurice Moderator Join Date: Feb 2006 Location: Wembley, Middlesex Posts: 7,225	Re: Stereo Console Bergamo GB (Grundig) - TX cooked Have you tried Radiomuseum? You would be better to get the original TX rewound. Mike Barker or Ed Dining can sort that for you. __________________ Forum Moderator http://www.michaelmauricerepairs.co.uk/

31st Aug 2017, 2:42 pm	#3
Reelman Octode Join Date: Aug 2008 Location: Rotherham, South Yorkshire, UK. Posts: 1,724	Re: Stereo Console Bergamo GB (Grundig) - TX cooked Bergamo was a generic name for a range of radiograms made by Grundig over a number of years. The last ones were transistor. Could this be yours.... http://www.radiomuseum.org/r/grundig..._st_cs200.html If it is, very nice. Have a very soft spot for Grundig audio kit. Used to love to go to the showroom in Orchard Street, just off Oxford Street. Good luck with it, Peter

31st Aug 2017, 6:59 pm	#4
Al (astral highway) Dekatron Join Date: Nov 2006 Location: London, UK. Posts: 3,496	Re: Stereo Console Bergamo GB (Grundig) - TX cooked Hey, Peter, that looks like the one! Thank you ! Amazing quality! Maurice , good idea. It first I'd like to establish if there is any fault downstream before making such an investment ... __________________ Al

31st Aug 2017, 9:07 pm	#5
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Stereo Console Bergamo GB (Grundig) - TX cooked Hi Al, always pays to use an HT fuse on these sets, either in the feed to the bridge or in the CT if it is full wave. It's a mod I do on most sets . Transformer should rewind OK. Ed

31st Aug 2017, 9:58 pm	#6
Al (astral highway) Dekatron Join Date: Nov 2006 Location: London, UK. Posts: 3,496	Re: Stereo Console Bergamo GB (Grundig) - TX cooked Cheers, Ed!good advice !! I'll PM you re the rewind, if it looks like there are no other faults downstream ... __________________ Al