Identify Avo Type 160 Bias Pot - UK Vintage Radio Repair and Restoration Discussion Forum

resurgance · 10th Apr 2021, 9:09 am

This is my first post Hi there
Am a radio Ham with a keen valve interest.

Have just started working on an early Type 160 valve tester serial number #1483 . No 'avo' on number

Can someone knowledgeable please confirm if the grib bias pot 10k Log is original?

It measured perfectly when desoldered I have not plotted the log yet. Am looking at fitting a Simpson 29T as per Dekatron's post as this came minus a meter. All else appears to be in good working order.

Thanks
Stew
ZL2VA

Dekatron · 10th Apr 2021, 9:51 am

It looks like the original from the number on the side, check this thread: https://www.vintage-radio.net/forum/...ad.php?t=68488 and also this one for a replacement designed by Mike Phelan: https://www.vintage-radio.net/forum/...ad.php?p=47426

The potentiometer is not logarithmic, only marked so, as it has its own design with three linear sections - you can see where the sections change in your photo as there are small indents in the track where that happens. This was made so that it would have higher resolution at lower grid voltages.

10th Apr 2021, 9:51 am	#2
Dekatron Octode Join Date: May 2009 Location: Linkoping, Sweden Posts: 1,465	Re: Identify Avo Type 160 Bias Pot It looks like the original from the number on the side, check this thread: https://www.vintage-radio.net/forum/...ad.php?t=68488 and also this one for a replacement designed by Mike Phelan: https://www.vintage-radio.net/forum/...ad.php?p=47426 The potentiometer is not logarithmic, only marked so, as it has its own design with three linear sections - you can see where the sections change in your photo as there are small indents in the track where that happens. This was made so that it would have higher resolution at lower grid voltages. __________________ Martin, Sweden

10th Apr 2021, 9:09 am	#1
resurgance Triode Join Date: Apr 2021 Location: Nelson, New Zealand Posts: 15	Identify Avo Type 160 Bias Pot This is my first post Hi there Am a radio Ham with a keen valve interest. Have just started working on an early Type 160 valve tester serial number #1483 . No 'avo' on number Can someone knowledgeable please confirm if the grib bias pot 10k Log is original? It measured perfectly when desoldered I have not plotted the log yet. Am looking at fitting a Simpson 29T as per Dekatron's post as this came minus a meter. All else appears to be in good working order. Thanks Stew ZL2VA Attached Thumbnails