> For me, changing the tuned inputs from 52-ohms out to 26-ohms out is
> preferable, Decrease L1, increase Cout, make Xc-in=20 - 25 ohms (Q=2.5 -
> 2.0). Tweak for best match. However, a second 8877 is only going to
> make c. a 2db difference at the Rx end, so it's a questionable
> expendature -- especially in view of extant tank problems when the second
> 8877 is added.
My comments were related directly to Alpha amps, Rich.
Alpha did not use pi network input circuits in the 77 series amps.
To prevent drilling many holes and adding expense, the "two-tube"
kits furnished an un-un instead. No tweaking was required if the input
L/C was correctly tuned to begin with.
I will not get into the pros and cons of how loud or not loud the
2nd 8877 makes you. This "kit" was a way around the FCC regs
that were in place at the time. Money is the motivation for converting
a 77DX to an SX. A profit of $1500-$2000 was not uncommon for those
in the "kit" installation business in the 80's.
(((73)))
Phil, K5PC
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