[Elecraft] K2/100 current consumption problem - update

[Fraser Robertson]

So far I haven't found anything wrong as such on #3764:

The LPF components appear fine (value and condition), and check out ok with 
an MFJ analyser for SWR on receive.

T1 and T2 and associated components appear ok.  One thing; C83 is 1000pF, 
not 1200pF as per circuit.  However I tried padding that with a 220pF SM and 
it made no difference.  Looks like 1000pF was supplied with the kit.

I've realigned the BPF on 160/80m, which was pretty much ok anyway.

I've re-adjusted the bias, which was also ok.

I've readjusted the pwr sense pot, again was ok.

With the PA disabled the base K2 draws about 2.5A @ 10W op on all bands.

With the PSU set to exactly 13.8V, and measuring the current (V across 
10x0R1 6W in parallel, in series with V+) I get the following, into a 50R 
load.  Current on the PSU display reads similar.

Set power W     Current A 160m     Current A 80m
50                    14                       14
60                    15                       15
70                    16.5                    16.5
80                    18                       18
90                     24                      19
100                   27                       20
110                   29                       21

The actual power out is similar to the set power, to about 10%.    So 
topband behaves ok up to about 80W op.  This also happens from a cold start, 
so I don't think it's thermal runaway.

No instabilities are apparent on a scope or spec. an.

Any suggestions appreciated.  Thanks / 73 Fraser G4BJM

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