SB-400 Question:

[Kechkaylo Dave (ATLINKS)]

To All:

I have a question about my SB-400. I went thru the entire alignment, but the
RF output power seems low: 100W on 80, 90W on 40, 80W on 20, 70W on 15, then
down to about 50W on 10M. The RF dummy load and wattmeter both check out
fine on other rigs.

The RF on pin 2 of the 6CL6 driver is 2 to 4 VRF, and I'm able to get
anywhere from 45 to 60VRF on the final grids. The 6146s are new, matched
units, but other 6146s give the same result. The high voltage is 765 VDC key
up, 706VDC key down; plate current 260 down to 210mA, depending on band.

The unit seems to load up right into a 50-ohm load, and other than this, it
operates fine, with the exception of the lower than anticipated RF output.

Can anyone on this list offer any suggestions? The SB-400 is used
stand-alone; i.e., it is not tested with the matching SB-300.

Regards,

Dave Kechkaylo, W8DLK/9

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