Westminster radio.W5355 - UK Vintage Radio Repair and Restoration Discussion Forum

sparkymike · 4th Apr 2018, 3:56 pm

Hi, I am working on a Westminster table radio c.1955. model W5335
Weird problem. When chassis is correct way up, panel lights come on.
Turn set the other way up to check various valve voltages and no panel lights

?? Mike.

tealandsilver · 4th Apr 2018, 4:07 pm

Check that bulb or holder isn't loose.

sparkymike · 4th Apr 2018, 4:13 pm

No it not that. Bulbs and holders are both clean and wiring looks ok.
Mike.

Herald1360 · 4th Apr 2018, 6:23 pm

Dodgy filament?

ukcol · 4th Apr 2018, 6:35 pm

If the fault hasn't been found by visual inspection then the best approach is probably to do a proper fault find.

Turn your chassis upside down so that the lights go out and then use a voltmeter to trace the fault. Start by measuring the voltage at the lamp holders.

sparkymike · 5th Apr 2018, 4:32 pm

Found the cause of the problem. So simple i could kick myself !! On one of the bulb holders, the wire tag rivet is not as tight as the other side and when turned upside-down, the tag moved and shorted to earth. I need to tighten the rivet a touch or replace complete holder. I now find that there is lack of ht on anode of 7C6 . There is HT on the other side of the anode high value series resistor.
Mike.

usradcoll1 · 5th Apr 2018, 5:49 pm

Possibly an extremely leaky "that" capacitor. Replace both cap and resistor.

sparkymike · 11th Apr 2018, 8:19 pm

Resumed work on the set and the 7C6 valve cathode pin is shorting to another pin,next to the heater pins, so will try another valve now.
Mike.

4th Apr 2018, 3:56 pm	#1
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Westminster radio.W5355 Hi, I am working on a Westminster table radio c.1955. model W5335 Weird problem. When chassis is correct way up, panel lights come on. Turn set the other way up to check various valve voltages and no panel lights ?? Mike.

4th Apr 2018, 4:07 pm	#2
tealandsilver Tetrode Join Date: Nov 2017 Location: East Lothian, Scotland, UK. Posts: 66	Re: Westminster radio.W5355 Check that bulb or holder isn't loose.

4th Apr 2018, 4:13 pm	#3
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Re: Westminster radio.W5355 No it not that. Bulbs and holders are both clean and wiring looks ok. Mike.

4th Apr 2018, 6:23 pm	#4
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Westminster radio.W5355 Dodgy filament? __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

4th Apr 2018, 6:35 pm	#5
ukcol Rest in Peace Join Date: May 2003 Location: Harlaxton, Lincolnshire, UK. Posts: 3,944	Re: Westminster radio.W5355 If the fault hasn't been found by visual inspection then the best approach is probably to do a proper fault find. Turn your chassis upside down so that the lights go out and then use a voltmeter to trace the fault. Start by measuring the voltage at the lamp holders.

5th Apr 2018, 4:32 pm	#6
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Re: Westminster radio.W5355 Found the cause of the problem. So simple i could kick myself !! On one of the bulb holders, the wire tag rivet is not as tight as the other side and when turned upside-down, the tag moved and shorted to earth. I need to tighten the rivet a touch or replace complete holder. I now find that there is lack of ht on anode of 7C6 . There is HT on the other side of the anode high value series resistor. Mike.

5th Apr 2018, 5:49 pm	#7
usradcoll1 Heptode Join Date: Mar 2017 Location: Cedar Grove, Wisconsin, USA. Posts: 823	Re: Westminster radio.W5355 Possibly an extremely leaky "that" capacitor. Replace both cap and resistor.

11th Apr 2018, 8:19 pm	#8
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Re: Westminster radio.W5355 Resumed work on the set and the 7C6 valve cathode pin is shorting to another pin,next to the heater pins, so will try another valve now. Mike.