Carl recommended looking at the other grid to ground caps.
Here's what I found, and summary of changes I'm going to make.
no shorts on these caps. I think they're both originals.
C208 is ceramic disc.
Markings: 103P.
Schematic says 0.01uF as does parts list.
Measures out at .014uF so okay.
C209 is electrolytic.
Markings: Sprague TVA-1301 2uF 50VDC, 85 deg C
Schematic says 2uF 25 WV
Parts list says 2.2uF 50V
This part looks like it could have suffered a little overheating
(slight bulge on ends?)
Measures 3uF. so thats +50% more than the 2uF marking.
I guess not critical? but odd that it's high.
Probably should replace the electolytic just in case it ain't perfect.
(leaky?)
hmm looking at Vishay/Sprague parts:
A Mouser # 75-517D50V2.2 Type 517D 2.2uF 50V radial electrolytic is
only 15 cents
but
A TVA-1301 Atom 2uF axial 85 deg C 50V goes for $1.04
and they have high temp 105 deg C versions of the TVA-1301 for $1.61
Looks like they call out lower leakage current for these compared to the
vanilla ones?
So I think I'll replace with the Mouser # 75-TE1301 (Type TE 105 degC
50V 2uF axial)
Looks like I already did get the parts for the svetlana bias change, so
I guess I'll put that in.
The yaesu bulletin called out a 10D10 diode which seemed more than needed?
(can't really find the spec for that part)
I have a 3A 1N5408 which should be good enough? Referencing the yaesu
TB-9627
bulletin at http://www.rfparts.com/technical.html.
Summary of all changes:
-two Xicon metal oxide 3W 22 ohm resistors to replace the suppressor
resistors
(the 5W ones are a full inch long? kinda big). These 3W seems the same
length as the 2W carbon.
-two Xicon metal oxide 3W 33 ohm resistors to replace the grid resistors.
-two CDE 200pf dipped mica caps (500v) to replace the grid capacitors at
the grid resistors
-TE1301 2uF electroytic 50v to replace a grid to gnd cap.
To fix the bandswitch, I have an old bandswitch to scavenge from.
Interesting that the wafer has contacts on top and bottom for the same
path...
I have to replace both on the 10M position.
and the svetlana bias change (using a 1N5408 for the diode)
thanks,
-kevin
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