[Elecraft] 160 Power loss

[Bob Hawkins]

Hi,

I have recently started to suffer power loss on 160M only. 

Symptoms are:
power OK on all bands at all levels except 160M.
On 160M power level ok above 1950 KHz. 
Power level uusally 0.0 at 1805.
Power output diminishes usually below 1900 KHz - the farther down you go,
the lower the power.
If frequency is set on another band power level is OK. Switch to 1850 -
power level starts close to normal and decays over 20 seconds to zero
power. This shows on the internal meter (ATU=Pout) and an external power
meter. At end of decay display will alternate between 0.0 watts out and a
Hi Curr message. 
Tuning receive signal loss is evident whenever transmit power is low.
Receive sensitivity goes to zero.  On low end of 160M there is random
static sound evident on some frequencies although AF Gain is not changed. 

I have reset the CPU (2.01H) and recalibrated the PLL. The power output has
been repeaked on the inductors L1-L13 and capacitors in the transmit stage.
This seemed to fix the problem. But it reappeared within an hour. Filters
have been recalibrated.

Something has gone, but I am not sure where. The radio will turn out up to
13-15 watts on bands above 160M, so the finals are OK.

Radio has SSB, NB, ATU, Internal 12V, Audio Filter, as well as 160M. The
RS232i/O was recently added.


Any suggestions???

73

Bob Hawkins ve3agc