The resistors are not critical except the Holcos must be the old style UK made ones. The current Holcos made by TE are not the same!
I only specified PRP because they are non-magnetic in construction and one could use Vishay RN60 as many of those are also non-magnetic. Standard 100 ppm is just fine.
The 565 that I am working on has schmutz from leaky cap and I am primarily looking at resistors and solder joints that may have been affected by the leakage. In general the board is very clean. As such IF I attacked any of the resistors, those in the signal path or associated with the power supply would be my main concern. I'm not terribly interested in opening and closing the case repeatedly.
Does anyone have any information on how many different versions of the PC board were produced and the associated time lines? The schematic I have shows two different power supply sections, one omitting C902-4 and one as an inset "ISSUE A POWER SUPPLY" showing C901-4. Mine is lacking the C901-2 and C903-4 are unpopulated. I would guess these are soft start/power surge protection. I am wary of adding C903-4.
Does anyone have any information on how many different versions of the PC board were produced and the associated time lines? The schematic I have shows two different power supply sections, one omitting C902-4 and one as an inset "ISSUE A POWER SUPPLY" showing C901-4. Mine is lacking the C901-2 and C903-4 are unpopulated. I would guess these are soft start/power surge protection. I am wary of adding C903-4.
The ADCOM GFP-565 is not known for a leaky cap issue. The brown goop you see is adhesive to keep the caps attached to the board reducing stress on the solder joints and avoiding cracked/broken connections.
There are 2 versions of the GFP-565 board - the original one with R901 and C901 in series across the power transformer secondary. The later issue A, has locations for the C901~C904 diode snubber caps. One can merely parallel (piggy-back) the caps right on top of the diodes if necessary.
The capacitor snubbers are added to reduce diode switching noise.
There are 2 versions of the GFP-565 board - the original one with R901 and C901 in series across the power transformer secondary. The later issue A, has locations for the C901~C904 diode snubber caps. One can merely parallel (piggy-back) the caps right on top of the diodes if necessary.
The capacitor snubbers are added to reduce diode switching noise.
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Thanks for the instruction. I do think at least on did leak (C107) or the assembler was very messy.
