Re: Topband: Air wound coil

2018-09-04 Thread Richard Beerman
Joe and others, Thanks for your helpful information. So, this will not be a difficult project at all. I have a pretty decent start on my radial system - only need to put down 10 more or so. I am kind of fired up about getting back on 160. It’s been a long time (40 years) since I was on the

Re: Topband: Air wound coil

2018-09-04 Thread Joe Subich, W4TV
> On 2018-09-04 1:18 PM, Richard Beerman wrote: Rick and Bob, Thanks for such swift replies. Looks like I should try to reinforce the 3/8” tubing (it’s pretty short) with a wood dowel or perhaps with smaller or larger aluminum tubing. Unless you want to redesign the antenna's taper schedule,

Re: Topband: Air wound coil

2018-09-04 Thread Clive GM3POI
Beerman Sent: 04 September 2018 17:18 To: Joe Subich, W4TV Cc: topband@contesting.com Subject: Re: Topband: Air wound coil Rick and Bob, Thanks for such swift replies. Looks like I should try to reinforce the 3/8” tubing (it’s pretty short) with a wood dowel or perhaps with smaller or larger

Re: Topband: Air wound coil

2018-09-04 Thread Richard Beerman
Rick and Bob, Thanks for such swift replies. Looks like I should try to reinforce the 3/8” tubing (it’s pretty short) with a wood dowel or perhaps with smaller or larger aluminum tubing. Then the fishing line method should be a perfect solution using 24 or 26 gauge wire. Using this method, I

Re: Topband: Air wound coil

2018-09-04 Thread Richard (Rick) Karlquist
On 9/4/2018 9:36 AM, Richard Beerman wrote: Anyway, here is my question…. my vertical has 3/8” tubing at the top. Pretty flimsy to connect top loading wires except maybe small gauge wire. I am not sure how well small gauge wire will handle voltages that may appear at the top of a 68’ vertical.

Re: Topband: Air wound coil

2018-09-04 Thread Richard Beerman
Top Banders, This discussion has been tremendously helpful to me as I also am going to put a DX Engineering 68’ vertical when the QRN subsides here in South Texas. Initially, I planned to install a large inductor (looks like it came from a BC transmitter) that I found at a local hamfest. My

Re: Topband: Air wound coil

2018-09-03 Thread Joe Subich, W4TV
Getting to six would result in a smaller top hat but may not be worth the mechanical hassle. If the mast has traditional three way guying, the mechanical hassle for a six wire top hat may not be that much greater than a four wire top hat. If the top hat wires slope downward, keeping them to

Re: Topband: Air wound coil

2018-09-03 Thread Paul Christensen
I ran the same model in 4Nec2 as below but changed the hat from the traditional two wires to four, spaced 90 degs. Complex base Z is near 16+j0. Even though two symmetrical top-hat wires produce little radiation, four wires result in wires that are only 24 ft long to achieve resonance --

Re: Topband: Air wound coil

2018-09-02 Thread VK3HJ
-Original Message- From: Eugene Colton Sent: Monday, September 03, 2018 12:25 PM To: donov...@starpower.net Cc: topband@contesting.com ; MU 4CX250B Subject: Re: Topband: Air wound coil Jim, @ say, 1.83 MHz, the electrical length of your vertical is about 47.4 deg, necessitating a top

Re: Topband: Air Wound Coil

2018-09-02 Thread Dan Maguire via Topband
Grant wrote: >>> Or the inverse as I did, cut my T for the low end of the band. Then three >>> series capacitors with PCB relays to short each individually (none, 1, 2, >>> or 3) yielded nearly full band coverage <1.5:1 swr. My T is 85' to top and >>> a 50:25 ohm TLT is a close match, then the

Re: Topband: Air wound coil

2018-09-02 Thread Eugene Colton
se insulator. Much better to use top loading to avoid high > voltage at the base. > > > 73 > Frank > W3LPL > > - Original Message - > > From: "Jim Garland" <4cx2...@miamioh.edu> > To: topband@contesting.com > Sent: Sunday, September 2, 2018

Re: Topband: Air wound coil

2018-09-02 Thread donovanf
rland" <4cx2...@miamioh.edu> To: topband@contesting.com Sent: Sunday, September 2, 2018 10:03:32 PM Subject: Re: Topband: Air wound coil On this general topic, I'm erecting a 68 ft aluminum self-supporting pole (DX Engineering) that is four inches OD at the bottom, tapering to about 1/2

Re: Topband: Air wound coil

2018-09-02 Thread Richard Schmiedt
Jim, I have that 80m quarter wave vertical by DXE and use a simple matching network with it for 160m. As it stands, the vertical is basically an 1/8 monopole with ~12 ohms real Z on 160, so I use a 4:1 balun to bring the 50 ohm coax down to 12 ohms then add a 4 inch diameter coil in series to

Re: Topband: Air wound coil

2018-09-02 Thread Paul Christensen
m Subject: Re: Topband: Air wound coil On this general topic, I'm erecting a 68 ft aluminum self-supporting pole (DX Engineering) that is four inches OD at the bottom, tapering to about 1/2 inch at the top. It is designed as a full size 1/4 wave 80m vertical. I'd like to use it on 160m. If I add

Re: Topband: Air wound coil

2018-09-02 Thread Dale Putnam
I have often used an Omega match, in this situation. Have a great day, --... ...-- Dale - WC7S in Wy "Actions speak louder than words" 1856 - Abraham Lincoln _ Topband Reflector Archives - http://www.contesting.com/_topband

Re: Topband: Air wound coil

2018-09-02 Thread Roy Koeppe
Jim, Maybe a combo of the two methods, that way you can tap up from the bottom of the loading inductor a few turns to get a perfect match for the coax feedline. Plus have the convenience of adjusting to resonance by tapping down from the top of the same coil. 73,Roy K6XK On this

Re: Topband: Air wound coil

2018-09-02 Thread Jim Garland
On this general topic, I'm erecting a 68 ft aluminum self-supporting pole (DX Engineering) that is four inches OD at the bottom, tapering to about 1/2 inch at the top. It is designed as a full size 1/4 wave 80m vertical. I'd like to use it on 160m. If I add four capacity hat wires at the top,

Re: Topband: Air wound coil

2018-09-02 Thread GEORGE WALLNER
ive GM3POI -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom Boucher Sent: 02 September 2018 18:20 To: 160 reflector Subject: Topband: Air wound coil Bob W7RH - you don't need expensive hard-to-find vacuum capacitors to match a quarter wave 'L' or 'T' o

Re: Topband: Air wound coil

2018-09-02 Thread Clive GM3POI
a DC short to ground for the antenna. No Caps needed. 73 Clive GM3POI -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom Boucher Sent: 02 September 2018 18:20 To: 160 reflector Subject: Topband: Air wound coil Bob W7RH - you don't need expensive

Topband: Air wound coil

2018-09-02 Thread Tom Boucher
Bob W7RH - you don't need expensive hard-to-find vacuum capacitors to match a quarter wave 'L' or 'T' on top band. I use cheap multilayer high voltage disc ceramics and these have been working perfectly at QRO levels with my inverted 'L' for years. I use 1600pF made up from 1000pF + 470pF + 220pf

Re: Topband: Air Wound Coil

2018-09-02 Thread W7RH
Per the following added comments. Me too. Or the inverse as I did, cut my T for the low end of the band. Then three series capacitors with PCB relays to short each individually (none, 1, 2, or 3) yielded nearly full band coverage <1.5:1 swr.  My T is 85' to top and a 50:25 ohm TLT is a

Re: Topband: Air Wound Coil

2018-09-01 Thread Mike Waters
It may very well be true that tank coils made from round copper have some slight advantages over edge-wound. But after all is said and done, does this really make a great deal of difference? :-) I have an edge-wound roller inductor in my homebrew amplifier.

Re: Topband: Air Wound Coil

2018-09-01 Thread Richard (Rick) Karlquist
On 9/1/2018 3:42 PM, Grant Saviers wrote: Me too. Or the inverse as I did, cut my T for the low end of the band. Then three series capacitors with PCB relays to short each individually (none, 1, 2, or 3) yielded nearly full band coverage <1.5:1 swr.  My T is 85' to top and a 50:25 ohm TLT is

Re: Topband: Air Wound Coil

2018-09-01 Thread Grant Saviers
Me too. Or the inverse as I did, cut my T for the low end of the band. Then three series capacitors with PCB relays to short each individually (none, 1, 2, or 3) yielded nearly full band coverage <1.5:1 swr.  My T is 85' to top and a 50:25 ohm TLT is a close match, then the capacitor stack

Re: Topband: Air Wound Coil

2018-09-01 Thread W7RH
Guys, I'm confounded by the complexity suggested for all band coverage of 160m "Top Loaded T Antenna". May I make a simple suggestion. A simple T antenna will have a radiation resistance of 10-12 Ohms with electrical height of say 43ft with a Good ground system of quarter wave radials. By

Re: Topband: Air Wound Coil

2018-08-31 Thread Guy Olinger K2AV
Hi Rick, Wes, I said it was a "killer piece of copper". I did not compare it to anything. Mostly I like the way that edge-wound coil looks (what was on my mind when I said "killer") The same way I like a lit up and glowing red 3-1000Z putting out 1500 watts, or the spooky glow of 866A's and

Re: Topband: Air Wound Coil

2018-08-31 Thread Jim Thomson
-Original Message- From: Richard (Rick) Karlquist Sent: Friday, August 31, 2018 7:13 AM To: Jim Thomson ; Guy Olinger K2AV Cc: TopBand List Subject: Re: Topband: Air Wound Coil ## What are you using to measure Q ?? I did discover one anomoly with coils and Q. XL increases

Re: Topband: Air Wound Coil

2018-08-31 Thread Richard (Rick) Karlquist
On 8/31/2018 6:09 AM, Jim Thomson wrote: ##  Are you sure about this ?   I have used  .25 edge wound rollers, I am sure that flat conductors result in lower Q than round conductor. I have done innumerable Q meter measurements to confirm this. I didn't say that flat conductors don't work

Re: Topband: Air Wound Coil

2018-08-31 Thread Jim Thomson
-Original Message- From: Richard (Rick) Karlquist Sent: Thursday, August 30, 2018 5:44 PM To: Guy Olinger K2AV ; Jim Thomson Cc: TopBand List Subject: Re: Topband: Air Wound Coil 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

Re: Topband: Air Wound Coil

2018-08-31 Thread Clive GM3POI
: Topband: Air Wound Coil Thanks again for all the replies Guys, I am running so late on getting ready for this season I am just looking for a quick and easy way out, I'll get the vertical up and see what I need, I might be over complicating things as usual, Thanks Trevor EI2GLB - Original Message

Re: Topband: Air Wound Coil

2018-08-31 Thread MR TREVOR DUNNE
ot;MR TREVOR DUNNE" Cc: "topband List" Sent: Thursday, 30 August, 2018 21:03:09 Subject: Re: Topband: Air Wound Coil 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 do

Re: Topband: Air Wound Coil

2018-08-30 Thread terry burge
few months more it's > been 4 already, > > Thanks > Trevor > EI2GLB > - Original Message - > From: MR TREVOR DUNNE > To: ''topband List' > Sent: Thu, 30 Aug 2018 07:44:04 +0100 (IST) > Subject: Topband: Air Wound Coil > > Hi All > > I'm lookin

Re: Topband: Air Wound Coil

2018-08-30 Thread Wes Stewart
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

Re: Topband: Air Wound Coil

2018-08-30 Thread VK3HJ
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

Re: Topband: Air Wound Coil

2018-08-30 Thread Richard (Rick) Karlquist
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

Re: Topband: Air Wound Coil

2018-08-30 Thread Guy Olinger K2AV
across the pond to speed it up. On Thu, Aug 30, 2018 at 5:55 PM Jim Thomson wrote: > Date: Thu, 30 Aug 2018 07:44:04 +0100 (IST) > From: MR TREVOR DUNNE > To: ''topband List' > Subject: Topband: Air Wound Coil > > > I'm looking for an Air wondering coil like in this lin

Topband: Air Wound Coil

2018-08-30 Thread Jim Thomson
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

Re: Topband: Air wound coil

2018-08-30 Thread Ralph Parker
>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 -

Re: Topband: Air Wound Coil

2018-08-30 Thread Brian Pease
e: Topband: Air Wound Coil 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

Re: Topband: Air Wound Coil

2018-08-30 Thread David Cutter via Topband
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

Re: Topband: Air Wound Coil

2018-08-30 Thread Don Kirk
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

Re: Topband: Air Wound Coil

2018-08-30 Thread Tim Shoppa
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

Topband: Air Wound Coil

2018-08-30 Thread MR TREVOR DUNNE
Hi All I'm looking for an Air wondering coil like in this link, 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 matching network for my 160m inverted T using it or something