Hello all
I'm going to call the list once more for help!
I found the following components out of use :
U1, Q6, Q7, Q12, Q10, Q11. All where replaced. Now, the amp by itself is
working
as expected, but and once more big BUT :
Very high current for the K2 (more than 4.8 A). Under 11 w (KPA off) in
TUNE, on the K2 indicated power 1w, Reflect 3.5/1 but 16w on the external
wattmeter.
Still high current. Over 11 w (around 15 to 20w) same display, Reflct 1.1/1,
but output wattmeter 60w.
This indication does not change whichever output I ask from 11 to 100 w, it
stay at 60 indicated.
R26, R27 are behaving correctly,
The bridge balance is OK taking the zero on R27 (no changes on the K2
display) U5 pin 1 and pin 7 no changes.
Jumping U5 pin 3 to pin one (after removing U5) voltage follow R27
variation, but U6 pin 6 (VRFDET) stay put at 0v.
So my conclusion is U5 and U6 dead!
The K2 without the KPA100 is working perfect, but just pluging the KIO cable
(K2 to KPA100 remote) or direct P1 to P4 disable the power control on the
K2.
The K2 is OK with the computer control too, but that has no relation with
the problem!
I ordered yesterday the op-amp replacement.
In the mean time, have you any other diag than mine? Thank you in advance
73 F5UL/Bob
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