[Elecraft] New KX1 low power and 20m oscillation

[Stan Gibbs]

Just finished building the KX1 and the transmit testing is not going well. My
only bench tool is a DVM.


Power supply is a 13V battery.  Ant is a 50 ohm dummy load. The receiver
seems to work fine.  All DC voltages on RX are nominal.

On 40m TX, I get about 1.5W out.  The signal is clean listening with my K3. 
On 20m TX, I get about 2W out but there is a horrendous audio oscillation. 
My P3 shows huge sidebands on the signal.

All the TX DC voltages look good EXCEPT for the base of Q7, which is
supposed to be 0.7V.  I measure
 -0.895V on 40 and -0.195 on 20.  I have examined all the suggested areas,
but I don't find any obvious problems.

Anybody have a suggestion of a cause of this behavior?  

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73, Stan - KR7C
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