[Yaesu] FT-101 Neutralization

[Stuart Bloom]

Hi,
I have a FT-101E.  I just finished re-neutralizing the
finals after finishing a PA tube replacement.  There
are many how-to's and stories about how the original
Japanese NEC 6JS6C tubes are somewhat different than
American tubes in inter-element capacitance.  This
results (at least in my case) in an inability to get a
proper neutralization.  The mod involves changing the
series capacitor (100pf) with a 10pf fixed cap (silver
mica, mica, or NPO) of AT LEAST 1000WVDC rating.  This
change allowed me to neutralize the "dip" per the
Yaesu instructions (the mod, so the story goes, also
prevents too high a capacitance if the variable cap
shorts out, leaving just the fixed cap.  The fixed
value of 10pf is closer to the desired final
capacitance).  You may not need to do the cap mod (it
may have already been done if you have American
tubes.)

If you don't have your manual, go to BAMA (boat
anchors manual archive) and download it for free. 
You'll need to take off the bottom cover to access the
hole through the finals compartment.  You'll need an
insulated screwdriver (we are talking 600 VOLTS)A
plain plastic one did not work for me.  The cap screw
was too tight and I destroyed the tip.  I had to use a
plastic one with a metal tip.

I don't want to get the actual procedure wrong, so get
the procedure out of the FT-101 owner's manual.  It
works.

This, and a good circuit card edge cleaning, cured my
low output on 160 meters AND cured my oscillation
problem on 10A and 10B.

73
Stuart
KD5HVO

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