I asked Ted Shannon at Henry Radio about a plate choke because I have spares
for most of my homebrew 3CX3000 amp, but not a plate choke.
Ted told me that Henry are no longer producing tube amps of that nature, don't
produce componenets and don't even have the specs to hand any more.
The stuff they sell on ebay they buy in.
I tried to get hold of a Peter Dahl choke, but it seems that they've gone out
of business and that Harbach have bought the rights to their name and designs.
However, Harbach told me that they only manufacture Peter Dahl transformers at
the moment, not chokes. And in any case, I can get cheaper and equal quality
transformers from TEC here in England - plus I don't have shipping costs.
B&W stuff seems unobtainable these days.
So.....
I think we have to go back to REAL home brew.
There seem to be plenty of designs in the literature over the years, and now we
have access to more effective test kit at a low price than the old tube type
dip meters of old - so why not get a teflon rod (about 5 bucks off ebay) and
wind one?
Speaking of cheaply available test kit, I bought a pretty new spectrum analyser
with a built-in sweep generator off a fellow Ham just recently to upgrade my
home brew one built 15 years ago. It's a quality German-made instrument that
he'd bought new recently, not dodgy Chinese trash and I was amazed that no-one
had shown any interest in his advertisement in the RSGB's magazine. I got it
for a really cheap price and when I mentioned that I'm recovering from spinal
surgery he even drove 200 miles to deliver it for me personally. It almost
restores my faith in human nature and made me feel guilty about haggling him
down on price!
So.....
See if you can find someone locally with a good frequency counter, LCR meter
and dip meter, wind a coil that looks kinda the same, short the ends out and
measure if there's a series resonance in the ham bands.
My amp runs a pi-L with rollercoasters on all bands 160-10m and I built my
choke as a single winding with a measured resonance on 12.2MHz. Although there
were one or two little dips elsewhere it hasn't exploded ......yet
If it helps I can send a spec and photos?
cheers
Dave G0OIL / K2MOO. Mooooooo.
--- On Sat, 13/12/08, W7RY <w7ry@arrl.net> wrote:
> From: W7RY <w7ry@arrl.net>
> Subject: Re: [Amps] WTB Henry Choke
> To: "N7SC" <n7sc@charter.net>, Amps@contesting.com
> Date: Saturday, 13 December, 2008, 5:39 PM
> Did you try Henry? They seem to be selling transformers and
> chokes on Ebay.
>
> 73
> Jim W7RY
>
> ----- Original Message -----
> From: N7SC
> To: Amps@contesting.com
> Sent: Saturday, December 13, 2008 8:41 AM
> Subject: [Amps] WTB Henry Choke
>
>
> GM All...
> Looking for a working HV choke used in the Henry Tempo
> 2002/2006/6N2
> VHF amplifiers...maybe even a parts amp. Please respond
> off list if you
> have anything available.
>
> Thanks...Steve
>
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