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Re: [Amps] Starting up a NEW Henry amp

To: "john@kk9a.com" <john@kk9a.com>, "amps@contesting.com" <amps@contesting.com>
Subject: Re: [Amps] Starting up a NEW Henry amp
From: Carl Braun <Carl.Braun@cattron.com>
Date: Mon, 11 Dec 2023 16:08:22 +0000
List-post: <mailto:amps@contesting.com>
Hello John

I am seeing high VSWR on my 7800 when using the Henry ULTRA amp.   I don't hear 
or see RFI on my monitored signal but the VSWR meter is certainly responding 
differently to the Henry amp than it does to my Alpha amp. By engaging the 
tuner on the 7800 I can get MOST of the Henry's VSWR down to under 1.5 or so.  
Placing a W2FMI line isolator (1:1) in between the 7800 and the Henry did 
nothing to lessen the high VSWR I saw coming back at the transceiver.  It 
should be noted that the RF console was approx. 3' from the transceiver at the 
time of testing with a 25' RG-58 exciter coa from the rig to the input of the 
amp. 

I've pulled my dummy load out of storage and am ready to test the amp with 
that.  The antennas I have been using with the Henry are all flat at their 
respective frequencies.  I see less than 1.3:1 at 1.5KW on my Powermaster II 
monitor, and on the 7800 VSWR meter, when using the Alpha.  Palomar is sending 
over a couple of choke kits for the radio room and the antenna feeds.  Choke 
kits for the TXCVR and AMP as well as 1:1 chokes for vertical antenna feed 
points.  As one responder noted; Henry basically suggests you don't use the 
tuner in the TXCVR to knock down any VSWR.  I plan on asking Dennis Pickering 
about the issue next time I have him on the phone.  

More experimenting later this week as I am currently wiring in a 240VAC feed on 
the opposite side of the radio room so I don't have to test the Henry consoles 
in close proximity of the operating position.  More updates afterward.

Carl W9LF

-----Original Message-----
From: Amps <amps-bounces@contesting.com> On Behalf Of john@kk9a.com
Sent: Wednesday, December 6, 2023 9:43 PM
To: amps@contesting.com
Subject: Re: [Amps] Starting up a NEW Henry amp

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Are you saying that the Henry is causing RFI in your transceiver?  Is this 
occurring with a dummy load or does you antenna feedline have CMC?

John KK9A



Carl Braun W9LF wrote?

By enabling the tuner in the rig I can knock down most of the SWR when running 
the Henry's but I don't have to do that with my other amp. One difference...  I 
do have a longer coax run (25') from the Henry's back to the PM II watt meter . 
The Alpha has a three ft (3') jumper from the amp to the watt meter. I'm going 
to shorten the coax from the Henry RF consoles to the coupler to 8' or so to 
see if that lessens any of the RF coming back to the rig. I do have a W2FMI 
line isolator in the line going to the amps with no visible changes. More parts 
are coming like RFI kits for the amp and transceiver, a 1:1 unun for the output 
of the amp and one for the base of the antenna.
Any other Suggestions?

Thanks

Carl W9LF


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