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

Focus Diode · 20th Sep 2018, 12:26 pm

Excellent work Christopher. I'll be having another look at mine later. Would be nice to see a couple of pictures.

Another forum member is kindly going to supply me with a suitable NOS 2M2 pot to replace the existing 1M control in the width position. I'll be able to remove the additional 680K feed resistor bodge too of course.

This is excellent as the usual plastic bodied types readily available don't seem to last long in old valved equipment they were never designed to be used in.

Uprating the feed resistor from 330K to 680K and the control from 1M to 2M2 is advised in both the 1400 and 1500 chassis. Later production models already have the new values in place.

It's surprising to note the same 330K/1M arrangement is used in the earlier 950 series but don't recall hearing stories of similar burn ups or recommendations to change them here.

20th Sep 2018, 12:26 pm	#51
Focus Diode Octode Join Date: Jan 2006 Location: Borough of Gateshead, UK. Posts: 1,420	Re: Stuck on a BRC 1400! Excellent work Christopher. I'll be having another look at mine later. Would be nice to see a couple of pictures. Another forum member is kindly going to supply me with a suitable NOS 2M2 pot to replace the existing 1M control in the width position. I'll be able to remove the additional 680K feed resistor bodge too of course. This is excellent as the usual plastic bodied types readily available don't seem to last long in old valved equipment they were never designed to be used in. Uprating the feed resistor from 330K to 680K and the control from 1M to 2M2 is advised in both the 1400 and 1500 chassis. Later production models already have the new values in place. It's surprising to note the same 330K/1M arrangement is used in the earlier 950 series but don't recall hearing stories of similar burn ups or recommendations to change them here.