[Boatanchors] Haligan and Xtal Filters

[Carl]

Thanks for the dates. I have all the 30's QST's and enjoy reading and 
rereading the articles.

My FBX, FB7X, FBXA, or FB7XA, or whatever else you want to call it gets 
used regularly on 30M with HB coils. Its a very credible performer there 
and keeps an equally old 30W TX clone company.

As far as the crystal filter, it was first described by William Cady in 
a 1922 IRE presentation

Carl
KM1H


----- Original Message ----- 
From: "BLIMPY" <blimpboy at sonic.net>
To: <boatanchors at mailman.qth.net>
Sent: Wednesday, December 10, 2008 1:41 PM
Subject: [Boatanchors] Haligan and Xtal Filters


>
> Moore's "Communications Recievers"    3rd Edition  page 5  has a
> chronological chart showing the emergence of new technological 
> features in
> communications recievers.
>
> It was Lamb  - a very prodigious contributor to radio technolgy  - not
> Halligan,  who published a description of a superhet with xtal filter 
> in
> August 1932 QST.
>
>
> The crystal filter first showed up commerically  in  Hendricks and 
> Harvey
> Custom variation 1 reciever, Dec 1932.
>
> Followed in quick sucession by Leeds Supreme (kit) , Hendricks and 
> Harvery
> variation 2, and then the National FBX,  in March and April 1933
> respectively.
>
> We know which of those was likely to have been made in any numbers.
>
> Following them.. a whole slew of really famous and even iconic radios 
> with
> crystal filters followed:
> McMurdo Silver
> Hammarlund Comet Super Pro
> RME-9
> Patterson PR-12
>
> In fact Hallicrafters didnt get on the bandwagon untill mid 1934 - 
> long after
> the crystal filter was an established fact of life in the few really 
> good
> radios of the day.
>
> Halligan did a lot of things... but introducing the Xtal Filter wasn't 
> one of them.
>
>
> What hallicrafters did primarily.. was make cheap radios that included 
> features pioneered by others, and made and plenty of them.
>
> Kind of like Skoda made cars in the soviet union...( read 2 cycle 
> clown cars)  Halligan made the S-38 and other AC/DC sets, and sets 
> without RF stages.
> Whoopee !
>
>
> _______________________________________________
>