[Amps] 2 x 8877

[Phil Clements]

> I would like to know the reason why the amps manifacturers
build linear amps
> using three 3cx800a7, 2 3cx1200a7, one 3cx3000a7 and
ruskies but no one
> build a linear amplifire with 2 3cx1500a7 (8877) such as
the Alpha sx.
> What problems they could have ?


Probably because a pair of 8877's is not near as cost
effective (dollars per watt) as several other choices.
Now that 8877's can be rebuilt for c. $450, this helps a
bit.

My philosophy on amp design has always been to select a
SINGLE tube that will run reasonably cool at the desired
power level.
I have no idea why amateur amp manufacturers stuff 3-4 tubes
in a box when one will do. Perhaps this lulls the "newbies"
into thinking that only one tube at a time will need
replacing. Rarely is the case, as the set should be fairly
matched so that the load will be as equally divided as
possible. Selecting a tube that is rebuildable is certainly
easier on the wallet in the long run.

(((73)))
Phil, K5PC