{Collins} KWM2 and 30L1 grid current issue



Hi all,

I have a kwm2 with PM2 power supply ,30L1 and station control with watt
meter speaker and phone patch.

I'm noticing a couple things that may be normal but I'm not 100% sure.

Comparing the output when I whistle vs when I use the Lock mode  The
KWM2 without the 30L1 does 105w with LOCK and about 90 with whistling. 
This is As I would expect.  When the 30L1 is hooked up it does 590-610
ish with the KWM2 in Lock but when I whistle only about 250-300W.  I
would have expected more like 500w judging from the 90w on whistling
into the mic I get on the KWM2.  During a QSO I rarely see the meter
over 175w.

As this is happening I'm also noticing something else that may be related.

Without the amp and with the kwm2 in LOCK when I set the mic gain at
about 30% or so the Plate flattens out and is no longer linear.  Also
about the same point of mic gain in "TUNE" mode is at about 350 and the
ALC is about 75% deflection. So this is also where I whistle into it...
any more mic gain and nothing good happens.  This is as expected.  This
is where I keep it during a QSO.

Now... when I turn on the AMP I never see any grid current with my voice
or whistle but only in tune or Lock. ALSO it says in the 30L1 book to
turn the mic gain to 75%.  So in LOCK when I put the mic gain to
anything less than about 50% the grid will start around 400 then slowly
bleed off to nothing over about 10 Seconds.  If I put the mic gain at
75% it will still bleed off but will stabilize around 250. output will
be 600 ish watts .

When I whistle or talk into the mic I'll never see any grid current with
my voice and output will rarely go over 250 even with a whistle. 
With the amp on the ALC is pegged if I set the mic gain over 30%.

Perhaps this is all normal but I'm afraid I have a leaky cap or a bad tube.

Signal reports say my audio is wonderful with or without the amp and
that with the amp I'm up about 2 S units.

Perhaps this is all normal it's the "grid" current that is freaking me
out when it bleeds off and when I see nothing on grid current with the
amp on.

Steve
KK4NNH




This archive was generated by a fusion of Pipermail (Mailman edition) and MHonArc.