UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Wartime civilian receiver what to replace Westector with ??

Mr 1936 · 14th May 2021, 8:50 pm

Hi

Looking at the Westector data sheet, the "knee" in the forward characteristic of a WX1 (single element) is at about 0.2 volts. The WX6 has 6 series elements so the 0.2 volts becomes 1.2 volts. I therefore find it quite surprising that in the WCR design the Westector is treated to 4V forward bias, pushing it well into a conducting state. I guess if it still conducts more in one direction than another then it still counts as a detector, albeit a rather "soggy" one. Maybe the designers found this gave the "best" performance.

If you replace with a single semiconductor diode, I suspect it would be happier with the forward bias reined in a bit or even reduced to zero.

14th May 2021, 8:50 pm	#8
Mr 1936 Heptode Join Date: Mar 2017 Location: Romsey, Hampshire, UK. Posts: 524	Re: Wartime civilian receiver what to replace Westector with ?? Hi Looking at the Westector data sheet, the "knee" in the forward characteristic of a WX1 (single element) is at about 0.2 volts. The WX6 has 6 series elements so the 0.2 volts becomes 1.2 volts. I therefore find it quite surprising that in the WCR design the Westector is treated to 4V forward bias, pushing it well into a conducting state. I guess if it still conducts more in one direction than another then it still counts as a detector, albeit a rather "soggy" one. Maybe the designers found this gave the "best" performance. If you replace with a single semiconductor diode, I suspect it would be happier with the forward bias reined in a bit or even reduced to zero. Attached Thumbnails Last edited by Mr 1936; 14th May 2021 at 9:02 pm.