UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Marshall JTM45 Guitar Amplifier- Mains (Primary)Fuse Blows

'LIVEWIRE?' · 11th Aug 2018, 11:50 am

I'd already downloaded & printed the schematic diagram from that site, Colin. It looks fairly straightforward, but one thing puzzles me a little, which is what is the function of the semiconductor diode connected between one side of the HT secondary and the o/p valve grid bias resistors, via some r's & c's?

11th Aug 2018, 11:50 am	#9
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: Marshall JTM45 Guitar Amplifier- Mains (Primary)Fuse Blows I'd already downloaded & printed the schematic diagram from that site, Colin. It looks fairly straightforward, but one thing puzzles me a little, which is what is the function of the semiconductor diode connected between one side of the HT secondary and the o/p valve grid bias resistors, via some r's & c's?