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'LIVEWIRE?' · 24th Oct 2017, 6:52 pm

Today I carried out some further checks on the PSU board, and found that D1 ( a SB260) which is used as a half-wave rectifier to provide the +7v line at CN4 was short-circuit How did I miss that!! I also replaced the 680uf smoothing cap., which follows D1, which I replaced with a 1N4007, and fitted 2 x 1uf Mtealized Poly. Caps in parallel to replace C17. Next job is to test the PSU, which means I either have to supply a +ve potential to the base of a switching transistor seperately, or connect the unit back up to the amplifier module in order to test it. The circuit concerned is a simple linear one fed from the secondary of a small transformer marked 'hanny 93 EE16', the primary of which is driven by the CS1N60 which was the original subject of this thread. Two SB260s are used one to provide the +7v supply, the other the -7v .
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24th Oct 2017, 6:52 pm	#33
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: What is a CSN60? Today I carried out some further checks on the PSU board, and found that D1 ( a SB260) which is used as a half-wave rectifier to provide the +7v line at CN4 was short-circuit How did I miss that!! I also replaced the 680uf smoothing cap., which follows D1, which I replaced with a 1N4007, and fitted 2 x 1uf Mtealized Poly. Caps in parallel to replace C17. Next job is to test the PSU, which means I either have to supply a +ve potential to the base of a switching transistor seperately, or connect the unit back up to the amplifier module in order to test it. The circuit concerned is a simple linear one fed from the secondary of a small transformer marked 'hanny 93 EE16', the primary of which is driven by the CS1N60 which was the original subject of this thread. Two SB260s are used one to provide the +7v supply, the other the -7v . .