Trevor,
I have found that winding a coil by hand may not look too hot but for a 160
Meter Inv-L they are easy to do. I use my Hytower with it's 65' radials as the
counter poise and run a 12 Gauge multi-strain house wire from Lowes over a big
Oak tree. Goes up and over the top and almost starts
I agree with Rick. The advantage to the edge-wound inductor is the better heat
dissipation; needed because the Q is lower :-)
Wes N7WS
On 8/30/2018 5:44 PM, Richard (Rick) Karlquist wrote:
On 8/30/2018 3:44 PM, Guy Olinger K2AV wrote:
You can also get the edge-wound (flat) 1/4 inch by 1/
I wind my air wound coils using 4 mm copper tubing on a form such as a baked
bean can. It holds its shape when the form is removed and I then stretch out
the coil longitudinally to achieve the pitch required. Inductance can be
easily calculated.
The copper tubing is very easy to solder and tap
On 8/30/2018 3:44 PM, Guy Olinger K2AV wrote:
You can also get the edge-wound (flat) 1/4 inch by 1/16 inch coil that they
use in the ATR-30 rotary coil tuner. That's a killer piece of copper.
Actually no. Edge wound is inferior in terms of Q to round wire.
It only makes sense for a rotary
The referenced Ameritron/MFJ part number is an 11 inch coil (aka BMW coil
stock of old), coil wound into 4 polystyrene rods. This one is 3 inches
diameter, four turns per inch, 10 AWG tinned bare solid copper.
This stuff is used in various Ameritron amps as part of the output Pi-L
networks. I have
Date: Thu, 30 Aug 2018 07:44:04 +0100 (IST)
From: MR TREVOR DUNNE
To: ''topband List'
Subject: Topband: Air Wound Coil
http://www.mfjenterprises.com/Product.php?productid=404-0669
I've had one on order from MFJ via a UK company for 4 months now and no sign of
it, I want to build a at match
Thanks for the replies I want to be able to tap it at various points to allow
for some movement up the band, I don't actually know how much inductance as I
don't have the antenna in place yet,
I wound a Homebrew coil last year but I fancied something tidier this time, I
was planning to install
>You can see a picture of the coil I wound for my 160M antenna match
here, along with some other more complicated link coupled tuners:
http://n3qe.org/tuners.html
Actual homebrew! Just like the good ole' days. Beautiful!
VE7XF
_
Topband Reflector Archives - http://www.contest
I used #10 plastic insulated solid "house wire" salvaged from
2-conductor + ground cable for the small 5 inch dia coil on my 630m
inverted-L. The insulation automatically provides a spacing of about 1
wire diameter and measured Q was 300 at 475kHz.
On 8/30/2018 8:31 AM, David Cutter via Topba
If you don't have plastic pipe, select a plastic beaker from the kitchen
cupboard.
David G3UNA-G6CP
-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Don Kirk
Sent: 30 August 2018 12:53
To: Tim Shoppa
Cc: Trevor; topband
Subject: Re: Topband: Air Wound C
To follow up on what Tim said, I often just use PVC pipe for my coil forms
and wind my coils using enamel coated wire (16 or 14 gauge enamel coated
wire), and to keep things simple I often just use close wound turns (no
space between turns). With no space between turns the coil loss will not
be mi
That is a very nice transmitter tank coil for a kilowatt amplifier. But if you
have already calculated or measured the inductance you need, you can just wrap
reasonable gauge insulated wire around any cardboard or plastic form you find.
I used magnet wire around a cardboard tube. You can see a p
Hi Trevor,
I ordered one of those coils from MFJ (Part # 404-0669) on July 6th and it
was on back order at that time, and it shipped from MFJ to me on August 1st
(when you order one and they are on back order I think it normally takes
them less than 1 month to produce new ones based on my experie
13 matches
Mail list logo
