UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

waran2005 · 8th Feb 2023, 9:55 pm

Hi, I have figured out that the needle had been bent, so in the wrong place compared to the moving coil and hence the difficulty in zeroing the meter and why the adjuster was originally hard to the left. The movement now appears to work really nicely, but it still requires a lot less than the 50 uA for FSD. I have no idea why it is doing this, both movements appear to be fine, I'm going to do what you suggest Martin and correct using resistors, at least for now, so I can carry on with trying to get it to function properly.

I'm going to strip the thumb wheels, check them, clean and lubricate - none appear damaged so that's good. I'm also going to replace eloctrolytics and repair the knobs the way Martin has suggested as a few are damaged and are missing the covers / caps.

Unfortunately this VCM will never be immaculate, it has suffered some corrosion and the paint is bubbling in places, but inside it is 100% original and clean. I think with the meters reading correctly it will work to some extent until fully calibrated.

What do you guys use to remove / prevent static charge build up on meter glazing?

Cheers,

Waran.

8th Feb 2023, 9:55 pm	#8
waran2005 Tetrode Join Date: Feb 2020 Location: Cardiff, Wales, UK. Posts: 65	Re: AVO VCM 163 Meters Hi, I have figured out that the needle had been bent, so in the wrong place compared to the moving coil and hence the difficulty in zeroing the meter and why the adjuster was originally hard to the left. The movement now appears to work really nicely, but it still requires a lot less than the 50 uA for FSD. I have no idea why it is doing this, both movements appear to be fine, I'm going to do what you suggest Martin and correct using resistors, at least for now, so I can carry on with trying to get it to function properly. I'm going to strip the thumb wheels, check them, clean and lubricate - none appear damaged so that's good. I'm also going to replace eloctrolytics and repair the knobs the way Martin has suggested as a few are damaged and are missing the covers / caps. Unfortunately this VCM will never be immaculate, it has suffered some corrosion and the paint is bubbling in places, but inside it is 100% original and clean. I think with the meters reading correctly it will work to some extent until fully calibrated. What do you guys use to remove / prevent static charge build up on meter glazing? Cheers, Waran.