[Hallicrafters] SX-71

[Roger D. Johnson]

I just put my restored S-76 on the bench and looked at the
input with my AEA CIA-HF analyzer. On the short wave bands
the input match is pretty good. The BC band is off scale!
As I said earlier, I think they deliberately mismatched
to keep the signals down on this band. 

As an aside, I found that the tracking on the BC band was
terrible. I found this on another S-76 also. I wound up
cutting the head off a brass 3/8-16 bolt and using that
to reduce the inductance. I gained a considerable amount
of gain at the low end of the band. I wonder if the SX-71
exhibits the same behavior.

73, Roger