[Boatanchors] Haligan and Xtal Filters

[Carl]

Ham type receivers used a single crystal into the 50's. The advent of 
the Collins mechanical filter led to rapid development of a competing 
technology and nulti pole filters became the norm almost overnight,

The multi pole filter was developed in 1934 and saw use in multiplex 
telephone systems for decades.

Ham engineers didnt have Al Gores invention of the Internet or Joe 
Bidens 1929 television shows to assist them in accessing the latest 
ideas........

Carl
KM1H


----- Original Message ----- 
From: "Dave Brown" <tractorb at ihug.co.nz>
To: <boatanchors at mailman.qth.net>
Sent: Wednesday, December 10, 2008 11:52 PM
Subject: Re: [Boatanchors] Haligan and Xtal Filters


> Likely a key issue. There are xtal filters and xtal 
> filters.......although I would have thought all these were single xtal 
> types but different circuits might have been considered different 
> enough to justify a separate patent.
> Some relevant info here....
>
> http://www.ieee-uffc.org/freqcontrol/crystal.html
>
> 73
> Dave
> ZL3FJ
>
> ----- Original Message ----- 
> From: <cemilton at aol.com>
> To: <dfischer at usol.com>; <km1h at jeremy.mv.com>; <blimpboy at sonic.net>; 
> <boatanchors at mailman.qth.net>
> Sent: Thursday, December 11, 2008 11:04 AM
> Subject: Re: [Boatanchors] Haligan and Xtal Filters
>
>
>>
>> Duane,
>>
>> What is the patent number and date?
>>
>> 73
>> W4MIL
>> Chuck
>>
>>
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: Duane Fischer, W8DBF <dfischer at usol.com>
>> To: Carl <km1h at jeremy.mv.com>; BLIMPY <blimpboy at sonic.net>; 
>> boatanchors at mailman.qth.net
>> Sent: Wed, 10 Dec 2008 4:57 pm
>> Subject: Re: [Boatanchors] Haligan and Xtal Filters
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> 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 !?
>>
>>>>?
>>
>>>>?
>>
>>>> _______________________________________________?
>>
>>>>?
>>
>>>?
>>
>>> _______________________________________________?
>>
>>>?
>>
>>>?
>>
>>>?
>>
>>> -- 
>>> No virus found in this incoming message.?
>>
>>> Checked by AVG. Version: 7.5.552 / Virus Database: 270.9.15/1838 - 
>>> Release
>>> Date: 12/8/2008 6:16 PM?
>>
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>>
>>> ?
>>
>> _______________________________________________?
>>
>>
>>
>>
>>
>>
>
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