Defective wirewound controls on Pye LV20s and D18Ts - UK Vintage Radio Repair and Restoration Discussion Forum

retroaudio · 17th Dec 2011, 10:03 pm

Hi,

I have a Pye D18T which doesnt work. One of the problems is that the wire wound controls on the back of the chassis are defective. I am unsure if they have went high or low or if the sliders are the problem.

I understand this is a fairly common problem in these sets and I wondered if anyone had come up with an economic way of overcoming this problem.

There is a problem in this set with defective B9G valve bases although at least you can purchase these although from what I can see from the net these are anything between £5-00 and £12-00+ each and are mostly ceramic the originals being paxolin.

Alex.

Boom · 17th Dec 2011, 10:23 pm

If you are lucky you might get away with stripping the sliders down for a good very careful clean. My came up fine. I'm still working on the valve bases but for now they have responded to a bit of wiggling with a fine pick to close up the contacts.

IJK2008 · 17th Dec 2011, 11:26 pm

Hi Alex

Have a look at this thread posts 10 and 11.

https://www.vintage-radio.net/forum/...ad.php?t=70963

I just swapped the frame hold and amplitude on my LV20 for resistors like this and they work OK.

Alternatively you might want to consider fitting rotary pots.

Regards

Ian

Danny · 18th Dec 2011, 2:07 pm

HI rotarys are the way forwards i have seen set with a new panel made up of paxolin and have also done this on a recent restoration. Danny

retroaudio · 20th Dec 2011, 1:02 am

Hi,

I had an opportunity tonight to go back to this chassis and take to pieces and clean all the controls with white spirit to remove any grease and dirt. I found half the controls within range and 3 had went low, None were open circuit and broken, just dirty. the ones which had went low were a couple of 10,000 ohm ones which were about 7,500 ohms and one 5,000 ohm one was sitting about 3,500 ohms it is it worth putting these back together or are they too far out of range to be effective.

Any advice greatly appreciated.

Alex

Danny · 20th Dec 2011, 10:00 am

Hi try passing some current through them and see if thay gain some resistance. thay were probrably not acurate when new anyway. Danny

IJK2008 · 20th Dec 2011, 4:28 pm

Hi Alex

This post shows a very neat and tidy solution:

https://www.vintage-radio.net/forum/...highlight=d16t

If I can get any more trouble then this is the way I will go.

Ian

Laurdys · 20th Dec 2011, 8:24 pm

this is also a good solution
https://www.vintage-radio.net/forum/...ad.php?t=70963 post 10

17th Dec 2011, 10:03 pm	#1
retroaudio Pentode Join Date: Mar 2005 Location: Cairneyhill, Fife, UK. Posts: 135	Defective wirewound controls on Pye LV20s and D18Ts Hi, I have a Pye D18T which doesnt work. One of the problems is that the wire wound controls on the back of the chassis are defective. I am unsure if they have went high or low or if the sliders are the problem. I understand this is a fairly common problem in these sets and I wondered if anyone had come up with an economic way of overcoming this problem. There is a problem in this set with defective B9G valve bases although at least you can purchase these although from what I can see from the net these are anything between £5-00 and £12-00+ each and are mostly ceramic the originals being paxolin. Alex.

17th Dec 2011, 10:23 pm	#2
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	Re: Defective wirewound controls on Pye LV20s and D18Ts If you are lucky you might get away with stripping the sliders down for a good very careful clean. My came up fine. I'm still working on the valve bases but for now they have responded to a bit of wiggling with a fine pick to close up the contacts.

17th Dec 2011, 11:26 pm	#3
IJK2008 Hexode Join Date: Feb 2008 Location: Glasgow, UK. Posts: 321	Re: Defective wirewound controls on Pye LV20s and D18Ts Hi Alex Have a look at this thread posts 10 and 11. https://www.vintage-radio.net/forum/...ad.php?t=70963 I just swapped the frame hold and amplitude on my LV20 for resistors like this and they work OK. Alternatively you might want to consider fitting rotary pots. Regards Ian

18th Dec 2011, 2:07 pm	#4
Danny Heptode Join Date: Jul 2003 Location: North Walsham, Norfolk, UK. Posts: 516	Re: Defective wirewound controls on Pye LV20s and D18Ts HI rotarys are the way forwards i have seen set with a new panel made up of paxolin and have also done this on a recent restoration. Danny

20th Dec 2011, 1:02 am	#5
retroaudio Pentode Join Date: Mar 2005 Location: Cairneyhill, Fife, UK. Posts: 135	Re: Defective wirewound controls on Pye LV20s and D18Ts Hi, I had an opportunity tonight to go back to this chassis and take to pieces and clean all the controls with white spirit to remove any grease and dirt. I found half the controls within range and 3 had went low, None were open circuit and broken, just dirty. the ones which had went low were a couple of 10,000 ohm ones which were about 7,500 ohms and one 5,000 ohm one was sitting about 3,500 ohms it is it worth putting these back together or are they too far out of range to be effective. Any advice greatly appreciated. Alex

20th Dec 2011, 10:00 am	#6
Danny Heptode Join Date: Jul 2003 Location: North Walsham, Norfolk, UK. Posts: 516	Re: Defective wirewound controls on Pye LV20s and D18Ts Hi try passing some current through them and see if thay gain some resistance. thay were probrably not acurate when new anyway. Danny

20th Dec 2011, 4:28 pm	#7
IJK2008 Hexode Join Date: Feb 2008 Location: Glasgow, UK. Posts: 321	Re: Defective wirewound controls on Pye LV20s and D18Ts Hi Alex This post shows a very neat and tidy solution: https://www.vintage-radio.net/forum/...highlight=d16t If I can get any more trouble then this is the way I will go. Ian

20th Dec 2011, 8:24 pm	#8
Laurdys Pentode Join Date: May 2009 Location: Stockton-on-Tees, County Durham, UK. Posts: 154	Re: Defective wirewound controls on Pye LV20s and D18Ts this is also a good solution https://www.vintage-radio.net/forum/...ad.php?t=70963 post 10 __________________ If it can be built, it can also be fixed.