[Boatanchors] Haligan and Xtal Filters

[Duane Fischer, W8DBF]

According to former Hallicrafters Chief Engineer, Fritz Franke, (and I have 
both a hand typed document as well as actual audio of it being said, 
Hallicrafters invented, and patented, the crystal filter and was the first 
company to incorporate it into a military receiver and later in an available 
to the public receiver. This was about 1937 +/-

----- Original Message ----- 
From: "Carl" <km1h at jeremy.mv.com>
To: "BLIMPY" <blimpboy at sonic.net>; <boatanchors at mailman.qth.net>
Sent: Wednesday, December 10, 2008 3:41 PM
Subject: Re: [Boatanchors] Haligan and Xtal Filters


> 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 !
>>
>>
>> _______________________________________________
>>
>
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