Here is part 7. The 160-15m manually tuned, tuned input is now complete.
And yes, the input swr is dead flat across each band. Note, the XL from
the fil choke is directly in parallel with the C2 cap of the PI tuned
input. (cold end of fil choke is bypassed to chassis). Depending on how
much uh is used in the fil choke, an equal amount of XC must be added to
the calculated C2 value. Then we also have to factor in the stray C from
EACH choke wire to chassis. Then we also have to factor in the tube's 42
pf from grid to cathode. With tube in socket, we have now tied the Stray
C from each fil lead together..and also added the 42 pf of grid to cathode
C. Typ, on the lowest freq (160 m), the C2 variable cap will be slightly
higher than the C1 cap. (C2 cap closest to cathode).
https://www.youtube.com/watch?v=ev-648v_G0I
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|