Reciever Alignment

[Glen Zook]

There is very little that you can do.  If you were to
adjust the variable capacitor on the oscillator for
one band, then all of the other bands will be affected
as well, not always in the direction that you desire.

The dials of these older receivers were designed for
an "average" of components.  However, with various
tolerances coming into effect, there were definitely
differences.  You need to look at the insides of a
Collins PTO to see what they did to get linearity over
just 1 MHz (in most models, some covered less).  There
are all sorts of mechanical adjustments made to get
the oscillator to track properly.

Especially on the general coverage receivers, they
were not designed to be frequency standards.  You just
got close with the dial and used a secondary standard
(like a 100 KHz calibrator) to make sure that you
stayed within the band.

Glen, K9STH

--- "Carl C. Miller" <bugmarx at EV1.NET> wrote:

I've noticed on some older receivers after alignment
that the ends of the bands will be dead on, such as
the BC band 550 and 1650 will be correct, but when
tuning to the middle of the bands, the frequencies
will be off maybe a few kcs high or low. What causes
this and what could one do to correct it?

=====
Glen, K9STH

Web sites

http://home.attbi.com/~k9sth
http://home.attbi.com/~zcomco

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