{Collins} Birdie question



I have been studying the 75S-3 architecture. This is no doubt the same as
several
other Collins receivers of similar vintage. For the low 200kHz of 40m:
  - 10.155MHz high-side crystal
  - 2.955 - 3.155MHz 1st IF
  - 2.499-2.701MHz PTO
  - 455kHz 2nd IF

A lashup of something similar to this on the bench leads me to think there
would
be a birdie at the 5th harmonic of the PTO at 7.0475MHz on the dial.

This corresponds to a PTO frequency of 2.6525MHz, of which the 5th harmonic
is
13.2625MHz.

I would very much appreciate it if someone could tell me whether this
birdie exists
(and/or if you like experiments, whether 13.2625MHz injected into the RF
input
when tuned to 7.0475MHz makes it through the front end filtering as a loud
image).

Thank you,

73, ian K3IMW




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