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Ian Jackson[_2_] Ian Jackson[_2_] is offline
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Default unkown output impedance measurement?

In message
,
Engineer writes
On Nov 3, 6:12*pm, Ian Jackson
wrote:
In message
,
Engineer writes


(snip)


But what does the invariable negative feedback (from the OPT secondary
to an earlier amplifier stage) do to the output impedance?
--
Ian


Ian, it reduces the source output impedance of the amplifier as a
voltage generator (increasing the damping factor) but does not affect
the speaker impedance to be used. The speaker impedance determines
the O/P tube plate (anode) load via the OPT ratio.
Cheers,
Roger


But the original question was "What the easiest ways to measure the
output impedance of a push pull tube amplifier?" It didn't mention
loudspeakers.
--
Ian