[Hammarlund] IF bandwidths?

[Chuck McGregor]

Eugene-
Before you put in a lot of time on this project, I suggest you check the 
specs of the target panadaptor.  Panadaptors with a 21 or 30 MHz IF were 
often intended for use with receivers operating in the VHF thru microwave 
ranges.  In these ranges, signal bandwidths tend to be much greater than 
the CW, AM and SSB signals we deal with in HF.  Accordingly the minimum 
panadaptor final IF bandwidth, which sets its resolution (or ability to 
discriminate two signals) was often in the tens to hundreds of kilocycles.

As an example, the Panoramic SA-3 Type T-3000NC, which was designed for a 
21.4 Mc IF,  had a resolution of 25 kc.  Any group of signals within 25 kc 
would appear as a single blip on the screen of this panadaptor, with no 
details of any of the signals discernable.

Some later panadaptors had variable IF bandwidths, thus variable 
resolution. Also many units, called panalyzors, included an input mixer to 
translate input signals to the panadaptor's design frequency (using an 
external local oscillator). So, my caution is just to verify the resolution 
of your panadaptor before you put in a lot of work or money to your project.

Best wishes for a successful project.

Chuck McGregor  N7RHU



> >On Wed, 12 Oct 2005 20:53:51 +0000 "Eugene Hertz" <ehertz at tcaf.org>
> >writes:
> >> Hello all,
> >>
> >> I am undertaking a project (probably foolishly) to adapt a 21.4mhz
> >> panadapter for use with various hammarlunds, specifically sp600,
> >> hq140x, hq129x. The idea is to use a balanced modulator, and no, I
> >> havent figured it all out yet (and it may not even be possible).


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