Surely the Henry 8K has not been forgotten already? Made In America!!!!
Don W7WLL
-----Original Message-----
From: Roger (K8RI) on TT
Sent: Friday, February 17, 2017 5:39 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] What am I missing....balun
Not long ago, it was easy to import some serious amps as long as that
manufacturer didn't have a US outlet. The Emtron DX-2sp loafs along at
the legal limit. It is quite capable of putting out 2500 PEP, but it
takes that kind of overhead to run 1500 out on digital. Tuned properly,
it puts out a very clean, legal limit signal. There were amps with a
pair of the same tubes, and another with a 4CX5000 (3 phase PS). Run at
1500 out at 100% duty cycle and the push pull cooling goes into high
gear and it is loud in a small room, neglecting the heat it puts out.
Add some compression while running 1500 PEP out and that amp goes into,
high blower.
Two large computers, plus my old 76A would drive me out of this room in
the summer. The CPUs use 200 watts, give or take with one at 220W under
full load. The video cards take 300W, so I'm looking at roughly 600W ea
for 2 computers plus the heat from the FT5000MP and the amp.
That's 2500 At a 20% duty cycle, or only 625 W average with the DX-2sp.
Many home brew amps use tubes with handles. Manual tune and relatively
inexpensive compared to Eimac 8877s. I have a 4CX3000 and a couple of
sockets that I'll probably never finish.. New and complete sockets for
that tube are definitely not cheap at $1600! Running the legal limit,
that tube could probably be cooled with a muffin fan.
The drawback? Many of these tubes take more power to light the fire,
than the average station runs. Add to that, the connectors, coax, and
antennas we use are not rated for a lot more than the legal limit. Oh!
Those amps are not only loud on-the-air, they are loud in the shack,
often necessitating a remote location for the amp
You can modify amps, and RF generators that weren't designed
specifically for ham radio, regardless of their designed power, or gain
as well We are well past needing the gain limitations that were
designed to keep ham amps out of CB hands.
The 3CX3000A7 can put out a very clean signal. Cleaner than most SS
rigs, but if memory serves as in IIRC, that tube is 10" tall and weighs
close to 9#? Not exactly the basis for a compact amp.
With the new transistors, pre distortion, and cleaner rigs SS legal
limit plus amps will soon be common place...for those who can afford
them. For now, they exist, but in the experimenter/home brew crowd.
73, Roger (K8RI)
On 2/17/2017 1:37 PM, StellarCAT wrote:
seriously? There are amps that are sold all-day-long that will easily
do 3 even 4 or more thousand watts! The statement when advertised for
sale as "used" that says "to a dummy load" as if they think the
reviewing audience is dumb enough to think that is how it was tested
or worse used!
Antennas that come with baluns and hardware designed for 5KW .... this
happens all the time.
200W on 30 meters?
there's nothing illegal about overbuilding something and selling it as
such as long as it doesn't require FCC cert ...
Gary
-----Original Message----- From: Richard Solomon
Sent: Friday, February 17, 2017 1:17 PM
To: towertalk
Subject: Re: [TowerTalk] What am I missing....balun
Just a side note, but I wouldn't
be so quick to advertise that I sell
components to those who violate
Federal Law.
73, Dick, W1KSZ
On Fri, Feb 17, 2017 at 11:12 AM, Jim Thomson <jim.thom@telus.net> wrote:
Date: Fri, 17 Feb 2017 07:41:09 -0700
From: Chris <EZRhino@fastmovers.biz>
To: "towertalk@contesting.com reflector" <TOWERTALK@contesting.com>
Subject: Re: [TowerTalk] What am I missing....balun
Is there any chance this is an April Fool's joke?
Chris
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73
Roger (K8RI)
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