[Heath] Heathkit "SB" Series IF Filters

[Kenneth G. Gordon]

On 12 Mar 2012 at 13:40, Eddy Swynar wrote:

> Hi Guys,
> 
> Recent exchanges here with Lee have made me realize that there remains
> a lot of "fog" in the minds of Heath aficiandos as to the
> characteristics of the different IF filters used in their "SB"
> line-up---and that fog still lingers in my own mind, too! Hi Hi
> 
> For that reason, if anyone is interested, I'll be only too happy to
> forward onto you a nice, brief summary of the different filters used
> in different models, complete with specific part numbers and
> characteristics---there are even a coupla schematic diagrams, & info
> on homebrewing your own filter clones...
> 
> You need only ask.
> 
> ~73!~ de Eddy VE3CUI - VE3XZ

Hello, Eddy:

I compiled a list of Heathkit filter types, to which equipment they belong, and 
how to modify them here:

http://www.w7ekb.com/glowbugs/ModsEtc/modifications.htm

Look down on the page a bit for:

"How to modify Heathkit HW/SB crystal filters for any bandwidth"

in PDF format.

I wrote this several years ago. Apparently not too many people know it 
exists, although some author did publish the schematics I drew in an article 
he wrote for ER magazine some time ago...without attribution. :-(

Ken W7EKB