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[AMPS] Henry 4K Ultra vs. 3K Classic X Mk II

To: <amps@contesting.com>
Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II
From: 2@vc.net (2)
Date: Tue, 2 Oct 2001 19:46:29 -0700
>
>Mike, unless Henry has come back out with the 4K Ultra, that's a rather old
>design that's "continuous tune" from 3.5 through 30 MHz and offers excellent
>coverage of frequencies between the ham bands, so used to be popular with
>government agencies, embassies, etc.  It had some neat features like a
>filament voltage adjustment and test points, 

//  Excellent idea.  Some Collins amplifiers had this feature.  

>not normally found on amateur
>equipment.  It's a good amp, but does not cover 160m and requires the
>typical "8877 three minute warm-up," which can be frustrating (for me).
>
//   Amen

>I just sold a 3K Premier (which is a 3K Classic X Mk III, virtually no
>difference with the Mk II) which had 160m coverage.  I don't recall if the
>"Mark II" covers 160 or not, maybe not.  The Mk III definitely does, as does
>the "Premier," whatever that means.  This was obviously a rather huge cost
>adder, as Henry used large B&W coil stock (not a toroid) to add 160m, as
>well as lots of HV doorknob padders switched in by their famous plunger
>switches driven by the bandswitch which also drives a chain, pulleys,
>triple-action camshaft (only kidding) and all that stuff that makes the
>bandswitch difficult to turn.
>
>I might have had a parasite problem with the 3K Premier, never investigated
>fully enough to ascertain; however I used to use the amp quite a lot on the
>lower bands (160, 80, 40) and one day noted a large change in the way it
>tuned on 40.  Still made 1500W output, but tuned in a different point,
>leading me to believe something failed.  Sure enough, investigation revealed
>two doorknob caps had cracked in half, leaving pieces of ceramic material
>laying around inside the RF cage, and with that, their values had obviously
>changed (or possibly dropped to zero).  These were 7500V caps 

//   What were the C values?
tnx

>-- Henry
>doesn't really skrimp on components.  

//  Henry Radio resonant-choke power supplies are formidable.  

>The parasitic suppressor on the
>3CX1200D7 still looked fine, although I didn't isolate the resistor from the
>inductor to measure the R.  But something made those doorknobs blow.
>
//  My guess is that it probably wasn't a parasite.

> ...

cheerz
>
>
>> Henry 4K Ultra (3CX1500A7) vs. 
>> Henry 3K Classic X MkII (3CX1200A7) 
>> > I have the opportunity to purchase one of these two amps.  Any help with
>> > the pros/cons of each would be appreciated.  Thanks.  Mike-K6QD
>> 
>> 
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>
>--
>FAQ on WWW:               http://www.contesting.com/FAQ/amps
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>
>


-  R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.  
end


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