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beery · 5th Jan 2021, 7:27 pm

Hi Ed,
R86 is 150K, 0.15M is just another way of writing it. It is a bit like the way that a 100nF decoupling capacitor is often labled 0.1uF.
The Low EHT is probably failing EHT caps, you might want to try disconnecting them to give the poor old transformer a chance. A gassey rectifier can also be a problem, but it would glow purple though.
R59, 350K is another one to check.

Ultimatley I would reccomend that you replaced the beader chain with something more trustworthy. You will find that apart from the 1/4W and 1/2W values, EMI resistors are not very good.

For the EHT smothing caps I used a couple of RS no. 384-7795

Cheers
Andy

5th Jan 2021, 7:27 pm	#25
beery Heptode Join Date: Jun 2006 Location: Ware, Hertfordshire, UK. Posts: 988	Re: My newly found Marconi 707 Hi Ed, R86 is 150K, 0.15M is just another way of writing it. It is a bit like the way that a 100nF decoupling capacitor is often labled 0.1uF. The Low EHT is probably failing EHT caps, you might want to try disconnecting them to give the poor old transformer a chance. A gassey rectifier can also be a problem, but it would glow purple though. R59, 350K is another one to check. Ultimatley I would reccomend that you replaced the beader chain with something more trustworthy. You will find that apart from the 1/4W and 1/2W values, EMI resistors are not very good. For the EHT smothing caps I used a couple of RS no. 384-7795 Cheers Andy __________________ www.youtube.com/user/andyvalve100