well in my 40 tb+ of mod files and pics i have taken over a 30+ year span i found the pic i took the day i modded the radio ..also a extract of the email he sent to me (bear in mind english is his second tounge )
"remove C110 (39nF) (sometimes not there ) and, if assembled, C127 (0.47uF).
This is part of the loop filter, because in this version of the pll module the loopfilter is already on the board.
move c116 to underside of mother board *(to make room for the module)
replace c123 (15pf) with 4.7pf
remove fl3 and replace with 103 disc cap (f3)
add 4.7pf cap as per pdf file"
that above ONLY if you use his module in the 642 ..not sure on 639 and variants
the filter is basically a highpass filter that cuts off the tx/rx below 26.6 or so ..fairly fast
as my module was setup to include the 26.330-26.770 mhz new zealand band i had to do the mod..
this is for the 1-642 i had a quick look at the 639 diagram but did not see it but then again i didnt look hard either ..tired and old and yeah you get the pic
if you only use the fcc and above bands you will not need to do this part of mod (if its on the board in the first place)
the cap goes across the two outer holes (center hole is a earth ) the thing is black in color ..i still have it around in the cupboard of doom but cant get to cupboard at this point
not sure whats inside it i am thinking some sort of cap/rfc combo as a highpass config but dont qoute me on that
mike