Right, I've got a Cushcraft R7 which fits your requirement of a
multiband vertical, but it's extremely narrowbanded. I rebuilt this
antenna a couple of years ago, partially for this purpose, but both
the documentation from the factory and my antenna analyzer say that it
never gets 1:1 anywhere regardless of what you do, and the SWR rapidly
climbs away from reality on either side of where you set the trap.
What I'm saying is that even with a multiband antenna, the SWR
situation eventually rears its ugly head.
I've got two or three tuners, none of which will do legal limit.
Something else to buy...lol
Somebody pointed out that I was facing 4:1 out on the edges of 80m
since I'd cut the dipole for 3800, and that's right, of course.
Whenever I wanted to work down between 3500 and 3600, I'd just been
turning the amp off out of paranoia. It's good to hear that I
shouldn't have to worry about that.
What I'm hearing is that the SB-220 should accept a VSWR of 4:1 or
better at the 500-800 watts at which I usually run it. Is that the
consensus?
Jeff/KD4RBG
---- Original message ----
>Date: Mon, 2 Mar 2009 17:55:32 -0600
>From: KBØNLY <kb0nly@mchsi.com>
>Subject: Re: [Amps] SB-220 and load mismatching...
>To: <amps@hidden-valley.com>
>
>Do your amp a favor, if you can't put up a mutliband vertical or dipole get
>a tuner after the amp. I run an old heathkit SA-2040 2kw roller inductor
>tuner. Sure, that means the tuner is taking the heat, but I would rather
>arc or burn up a tuner instead of a spendy part in a amp. Consider the cost
>of a tuner compared to a cost of a new set of tubes or load cap, its cheap
>insurance.
>
>Scott KBØNLY
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