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THE AM BULLETIN BOARD => Technical Forum => Topic started by: ka2zni on May 01, 2007, 09:03:00 AM



Title: 100% duty cycle amplifier for AM ??
Post by: ka2zni on May 01, 2007, 09:03:00 AM
Hello all... Was talking to several on amplifiers today and for hammer down, get after it am'ing I was told to be careful of the al-80a, and was wondering what would be a more suitable amplifier.. I was looking at a Henry 3K Console model with the (2) 3-500z's but was wondering what you were all using, and what works/what doesn't...

Thought this would be a neat post/topic to get some threads going..

http://cgi.ebay.com/Amateur-Radio-Henry-2K-HF-Linear-Amplifier_W0QQitemZ110120671527QQihZ001QQcategoryZ48700QQcmdZViewItem


Title: Re: 100% duty cycle amplifier for AM ??
Post by: N6WDR on May 01, 2007, 09:27:47 AM
I am currently using the Henry 2K Classic Console with no problems ;D, I have had it in line for 5 years now.  I am in the middle of home brewing up a russian GU84b tube amplifier, to see how it will work 8).

Richard N6WDR


Title: Re: 100% duty cycle amplifier for AM ??
Post by: WA1GFZ on May 01, 2007, 10:15:09 AM
I think 1 KW dissipapion is bare minimum. 3KW dissipation or more is much better. Or go 10 KW dissipation and run hard class A (plate current doesn't change when you talk) This is the best method because when a slop buck comes around all you need to do is talk louder switching your operating point to AB......and strap the bastid mode.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: flintstone mop on May 01, 2007, 10:25:04 AM
I like GFZeds approach.
I am using a Ten Tec Titan 425, a pair of 3CX800 and it will run (375 Carrier+ modulation) all day.
The Henry$ are hard to break. Ameritron with the so-called 2500 W power supply would be a healthy choice too. The bigger amps use the "un-pretty" ceramic pubes.
Have good success searching/building.
Fred


Title: Re: 100% duty cycle amplifier for AM ??
Post by: WA1GFZ on May 01, 2007, 02:46:23 PM
my 4X3 I would set it to 700 ma and talk softly.....or talk loud if needed. need to get that one back on with the new gay caps.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: N3DRB The Derb on May 01, 2007, 05:59:37 PM
thats right ( thats right)

bring your signal out of da closet. I wouldn't trust a old buzzardly Cardwell with a 4X3. It would melt. HIRAM WOULD NOT APPROVE.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: WA1GFZ on May 01, 2007, 07:57:27 PM
I keep cooking the bearing of the 2000 pf cardwell loading cap and I flashed the 7 KV Johnson one day while motivating the log antenna on 20 meters shooting fish in the barrel. It needs more strappage in the cap dept.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: W1GFH on May 01, 2007, 08:18:09 PM
Perhaps painting the gay caps with a manly black crackle finish and stenciling "DANGER: LETHAL VOLTAGE" warnings on them would make them a bit more "butch".


Title: Re: 100% duty cycle amplifier for AM ??
Post by: ka2zni on May 01, 2007, 08:52:48 PM
I think 1 KW dissipapion is bare minimum. 3KW dissipation or more is much better. Or go 10 KW dissipation and run hard class A (plate current doesn't change when you talk) This is the best method because when a slop buck comes around all you need to do is talk louder switching your operating point to AB......and strap the bastid mode.

 ;D

You have a point there....  ::)


Title: Re: 100% duty cycle amplifier for AM ??
Post by: Steve - WB3HUZ on May 01, 2007, 10:40:25 PM
I recommend the CAI CL-35.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: N3DRB The Derb on May 01, 2007, 11:11:40 PM
Quote
Perhaps painting the gay caps with a manly black crackle finish and stenciling "DANGER: LETHAL VOLTAGE" warnings on them would make them a bit more "butch".
No, they just be mo nappy then. I cannot attest to their hoeness.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: W1GFH on May 01, 2007, 11:39:42 PM
What's so gay about vacuum variables, anyway?


Title: Re: 100% duty cycle amplifier for AM ??
Post by: N3DRB The Derb on May 02, 2007, 04:46:35 AM
they look like butt plugs. Butt plugs that can take a TREMENDOUS amount of anal voltage before they flashover.  ;D

ummmmm......did you folks lose some your humor while I was away? That's something I would have said over the air back in the day and not thought twice about. But maybe I picked up some bad habits from the teenage gaming crowd online. Sorry if I offended anyone.

that vacuum variable looks JUST RIGHT. ;)


Title: Re: 100% duty cycle amplifier for AM ??
Post by: WA1GFZ on May 02, 2007, 09:49:40 AM
vacuum caps are great in rigs but I'm not crazy about using them in tuners. Vacuum caps don't like flash overs because of the close plate spacing. One blob of copper can make it a .22 target.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: flintstone mop on May 02, 2007, 11:00:50 AM
Thanks DERB
Now I can have something to comment about on my radio show why Vacuuuum Variables are Gay caps...............butt plugs..........high anal voltages, etc
Fred


Title: Re: 100% duty cycle amplifier for AM ??
Post by: W1GFH on May 02, 2007, 04:19:58 PM
If there are gay caps then there must be gay tubes.


Title: Re: 100% duty cycle amplifier for AM ??
Post by: WA1GFZ on May 02, 2007, 07:44:29 PM
that's an innie a-node.....outie a-node is more girl lovin manley

older larger outie a-nodes have love handles for a better QRO ride
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