"- - Bill - -" exray@coquidotnet wrote in message
...
Uncle Peter wrote:


Just a few general notes if no answers forth coming:

1: Measure the LO with a counter at the low end (if there is no
adjustment for setting the low end of the tuning);
that will tell you if that band uses hi or lo side injection.
It makes a big difference if set wrong!!!

Not on an S-38! It probably won't track well enough to determine for
sure.


My S-38s track pretty well. The maximum error is about the width of the
dial pointer. That's on a S-38(No suffix), 5R10A and a S-38D. Band 4
is most sensitive to lead dress, and fussing around with it helped.

In each case, high side injection gave a much greater error.



2: If the osc. section of the tuning cap uses smaller sized plates,
the
radio is probably hi side injection.

Ya might want to rethink that suggestion Pete. Any set with AM band
on
it will have smaller osc plates.

All the Hallicrafters SW radios I seen use the same size oscillator and
RF tuning capacitor sections. They use both a padder and trimmer for
the AM broadcast band. The S-38s use only trimmers for the higher
frequency bands. I certainly haven't seen them all, and that includes
the S-38E.



I was recently struggling with a cheapo little SW radio and it
tracks/tunes/rejects images about the same (which means not very good)
no matter which way ya go on the upper band. Low side may have had an
edge in this particular case but it would take a jury of sharp-eared
engineers to decide.

-Bill M


In my expirence with similar radios, the tracking should be good, the
peaking should be reasonably close but broad on the top 2 bands, and the
image rejection gets pretty poor above 10 Mc or so.

Frank Dresser