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Radio Wrangler · 6th Dec 2015, 11:43 pm

There were articles all over the place about substituting FETs in place of thermionics. One ploy was to use a cascade structure with a high voltage device on top (FET or bipolar) this was manufactured for a while as the 'Fetron'

I read about them in 'Ham Radio' (American) magazine and in Pat Hawker's column in Radcom as well as in WW

Another ploy was to use FETs in all places, and to reduce the HT voltage to something better suited to them.

Unfortunately these ploys foundered on the issue of dynamic range. They just got known about around the same era that interned problems in a variety of classic receivers came to light and few people wanted to make things worse.

David

6th Dec 2015, 11:43 pm	#61
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,903	Re: Eddystone 888A. There were articles all over the place about substituting FETs in place of thermionics. One ploy was to use a cascade structure with a high voltage device on top (FET or bipolar) this was manufactured for a while as the 'Fetron' I read about them in 'Ham Radio' (American) magazine and in Pat Hawker's column in Radcom as well as in WW Another ploy was to use FETs in all places, and to reduce the HT voltage to something better suited to them. Unfortunately these ploys foundered on the issue of dynamic range. They just got known about around the same era that interned problems in a variety of classic receivers came to light and few people wanted to make things worse. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done Last edited by Radio Wrangler; 6th Dec 2015 at 11:53 pm.