Sounds like output coupling is not happening, if grid current is
higher on 160 and output is lower. Calculate the reactance of your
blocker capacitor, for one thing. I get about 49 ohms at 1.8 MHz,
which is excessive. One ususally sees about 10 x this value of
capacitance as an anode blocker for high power at 1-2 MHz.
73
K5PRO
John
>I am almost finished with the new homebrew yc156 amp.
>It works fine on 15 - 80 meters but I am having a problem with
>160.
>
> With 5000 watts in, I am getting about 1200 watts out.
>
> I have added inductance to the plate and cathode chokes, changed
>(padder caps for the load to 400 pf/ 7.5kv) , and setup the tank
>several
>times. The blocking cap is a 1900 pf .
>
> THe other sympton is that grid current is much higher on 160 than
>all the other bands.
>
>what am I missing?
>
>TIA for any assistance
>
>Lynn NO9Z
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