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Old 13th Nov 2017, 3:37 pm   #8
newlite4
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Join Date: Nov 2003
Location: Bath, Somerset, UK.
Posts: 1,379
Default Re: BEME Mini Loop - silent

Hello Ian, yes, Sean was over yesterday and we carried out measurements around the DK91 (heptode wired as a pentagrid converter), it is a very crafty but established layout. I have full HT of 82V on pin 2 (anode) I have around 50V on pin 3 (grid 2), I will scope pin 6 (grid 3) to look for amplified RF and pin 4 (grid 1) for oscillator feedback later.
I am beginning to suspect the valve base, there is no other reason why this stage should not work apart from a very stubborn oscillator section.
Thanks for getting in touch,
Neil
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