[HBR] Use of single 1610 kcs transformer?

[Walt Hutchens]

> I only have access to one genuine 1600 kcs IF transformer.  I do not have
> access to a second to emulate any of the HBR 1600 kcs dual IF transformer
> configurations.  What would be the "penalty" for not conforming to this
> configuration?

Image suppression at the 2nd IF: For a 100 kcs 2nd IF that will be 200
kcs away, on the opposite side of the 2nd LO. Since the LO is at 1700
kcs, the image at 1800 kcs will be stronger than for the
two-transformer version. I can't recall which bands have the 1st LO
above and which, below, the channel frequency, so I can't take it any
farther than that, but just stick in '1800 kcs' instead of '1600 kcs'
for the 1st IF in the channel freq. calculation.

When the 1st LO is above the channel the increased image response will
be 200 kcs LOWER than the channel, when the 1st LO is below the
channel, the increased image will be 200 kcs HIGHER.

I think I have that right.  ;-)

You could leave space on the chassis to add the second transformer
when you locate one.  Or add a single tuned circuit using a toroid.

Walt
KJ4KV