Re: Topband: In search of resonance

2014-01-30 Thread Tom W8JI
Tom > It could be from a few things, but two closely spaced conductors, with the "parasitic" conductor resonant near the target band of the fed cond

Re: Topband: Compromise vertical loading questions

2014-01-30 Thread Björn SM0MDG
Thanks for all the input received. In short it seems like lifting the coil would not do much difference. Raising/increasing the angle of the top loading spokes might be the better option. Then of course moving the antenna to the water and improving the radials including some going into the wat

Re: Topband: 8Q7BM on Topband

2014-01-30 Thread Björn SM0MDG
Here is another update from 8Q7BM; Wednesday evening FT5ZM started so I moved away from 23.7 to 33.7. I was calling from about 1430 and on. Heard OH5KW 579 during the evening and logged VK3EW and A45XR. Other than that it was FT5ZM and their weak pileup heard here. On Thursday morning I started

Re: Topband: In search of resonance

2014-01-30 Thread chetmoore
Thanks for this tidbit of information. As soon as this white manure melts (some people call it snow) I will do a re-check on my shunt fed tower. I think I did have at least one dip to zero and never did find a resonance point. Thanks Chet N4FX -Original Message- From: Topband [mailt

Re: Topband: Short receiving verticals question

2014-01-30 Thread Bill Cromwell
On 01/30/2014 02:42 PM, Joe Subich, W4TV wrote: > A possible answer might be here: > > http://www.legupenterprises.com/ Doesn't faze the deer around here. They come right up to the house and the fenced kennels and munch on whatever they like. That stuff may do something with the small animals

Re: Topband: Short receiving verticals question

2014-01-30 Thread Joe Subich, W4TV
> A possible answer might be here: > > http://www.legupenterprises.com/ Doesn't faze the deer around here. They come right up to the house and the fenced kennels and munch on whatever they like. That stuff may do something with the small animals but the Eagle, Great Horned Owl, Red Tail Hawk a

Re: Topband: Speking of Hardline

2014-01-30 Thread Pete Smith N4ZR
I don't know about anyone else's cable company, but when the prices of scrap metal went up a few years ago Comcast emptied out their local scrap yard. Actually, I'm just supposing that's the reason. I got a lot of good stuff there while they were willing to let it go. 73, Pete N4ZR Check out

Re: Topband: Short receiving verticals question

2014-01-30 Thread donovanf
At the speeds that deer run across an open field, I doubt that repellant will help. Seven foot fence posts work perfectly, and they will last a lifetime! 73 Frank W3LPL - Original Message - From: "Gary Smith" To: Topband@contesting.com Sent: Thursday, January 30, 2014 6:42:57 P

Re: Topband: Short receiving verticals question

2014-01-30 Thread Gary Smith
> The biggest problem with the top hat is deer catching > the wire/string and bending the element or some rodent > eating the string. A possible answer might be here: http://www.legupenterprises.com/ They sell predator urine which discourages animals from going near the smell. My YL uses it to

Re: Topband: Speking of Hardline

2014-01-30 Thread Wayne Kline
Good suggestion Ray. When I moved to this QTH was TIGHT... I went to the local Cable Co. and spoke to the line Boss. He gave me all the cable ends I wanted I originally feed my 4 towers with 3/4" 75 ohm Catty hardline. Give'em a try . Wayne W3EA PS I also had permission to cl

Re: Topband: Submerging variable caps in oil as substituteforvacuum variables

2014-01-30 Thread Tom W8JI
Very true but the RF is still in the oil "dielectric" from the coax connector to the hot end of the resistor. Not the same at all. Loss tangent is meaningless in the dummy load application because impedance is low (weak electric field). There is very little displacement current compared to

Re: Topband: oil-submerged variables

2014-01-30 Thread Gary Smith
I might have some big micas that would work. What value would you need? Gary KA1J > Thanks, everyone. I had not thought about the possible difference > between 600M and 160 in terms of heating. Jon's suggestion of using big > old micas sure seems like a good one if I can find what I need. As

Re: Topband: In search of resonance

2014-01-30 Thread Tom W8JI
You might be dealing with AM BCB being detected by the meter - and masking what you are looking for. No, because he gets a dip to zero reactance. If that happens anywhere, there is no BCI. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband

Re: Topband: Speking of Hardline

2014-01-30 Thread Ray Benny
Have you tried the actual cable companies? My local Cableone cable service gave me a spool with about 800 ft on it. At the time, they had probably 6 - 8 spools with odds lengths in their yard, so giving one away was no big deal. Sometimes a case of beer helps make a deal! Ray, N6VR Chino Valley

Topband: Speking of Hardline

2014-01-30 Thread Gary Smith
I've asked the local cable installers if they have any extra hardline & no cigar. I need around 400' of it so Andrews is out of the question. I'd like the 50 ohm line but will probably have to settle for aluminum jacketed 75 ohm line. Any suggestions where else I might look to find something u

Re: Topband: Short receiving verticals question

2014-01-30 Thread donovanf
Hi Doug, A few notes about the short verticals in my 160M passive receive array. I use them in my W8JI broadside-endfire passive array described in detail on Tom's home page and on W5ZN's home page. Its important to understand that the loss in the radial system of a 160M passive receive a

Topband: Topban: FT5ZM

2014-01-30 Thread lmlangenfeld tds.net
I managed to work RI4ANF last fall with 100W and a hastily strung 90' EFW (w/essentially no RF ground), no part of which was hung higher than 15' off the deck. I can't imagine anything more NVIS than that. Mark -- WA9ETW > -- > > > > Some of my best Antarctic area co

Re: Topband: In search of resonance

2014-01-30 Thread Tree
You might be dealing with AM BCB being detected by the meter - and masking what you are looking for. On Thu, Jan 30, 2014 at 9:14 AM, Tom W8JI wrote: > I cannot get the inverted L to provide a dip on my MFJ 259 analyzer > anywhere in the 160 meter band. I get dips at 8.2 MHz (R=36 ohms X=0) wi

Re: Topband: In search of resonance

2014-01-30 Thread Tom W8JI
I cannot get the inverted L to provide a dip on my MFJ 259 analyzer anywhere in the 160 meter band. I get dips at 8.2 MHz (R=36 ohms X=0) with reactance on each side of X=0. At 5 MHz R=40 ohms X=0 with reactance on each side of X=0. I cant get any significant dips neat the 80 or 160 band. Ho

Topband: Not seeing your posts?

2014-01-30 Thread Tree
I have been getting emails from KV4FZ talking about not being able to post to the list. Emails directly to him are bouncing. I will try this channel as the message applies to a few others who are having the same issue. If your email does not show up here right away - the most likely reason is th

Re: Topband: Bad tower shunt capacitor

2014-01-30 Thread James C. Hall, MD
Jon: Thanks for this. This has crossed my mind since I use hose clamps to attach the wire from the top and bottom of the caps. I had used copper flashing between the two caps. I'll change that to a heavy insulated wire. Get out the NoAlOx too. :) Thanks again. 73, Jamie WB4YDL -Original Mes

Re: Topband: Submerging variable caps in oil as substituteforvacuum variables

2014-01-30 Thread Shoppa, Tim
That uses the thermal properties outside a resistor, not dielectric constant properties in a capacitor :-). Tim N3QE - Original Message - From: ZR [mailto:z...@jeremy.mv.com] Sent: Thursday, January 30, 2014 11:28 AM To: Tom W8JI ; HAROLD SMITH JR ; Shoppa, Tim; n...@contesting.com ; to

Re: Topband: Short receiving verticals question

2014-01-30 Thread Bernie McClenny, W3UR
Ok Frank I will forward this to the Topband reflector. Bernie McClenny, W3UR Editor of The Daily DX and The Weekly DX www.dailydx.com 410-489-6518 Sent from my iPhone On Jan 30, 2014, at 10:56, donov...@starpower.net wrote: Hi Burny, When you have a chance, please forward this email to the To

Topband: In search of resonance

2014-01-30 Thread Carl Braun
Hello to the group I'm a newbie to 160 having only participated in various contests over the course of the last two years. I used an 80 meter aluminum tube vertical with a Reyco trap affixed to the top with a horizontal "L: wire heading over to the palm tree. I've since converted that antenn

Re: Topband: Bad tower shunt capacitor

2014-01-30 Thread Herb Schoenbohm
Wouldn't 1 5/8 hardline make a better HV RF capacitor? Herb, KV4FZ On 1/29/2014 11:34 PM, HAROLD SMITH JR wrote: Jamie, The VSWR would change because the arc would change the impedance at the Arc point. From perhaps several hundred or thousand ohms to near Zero during the Arc.. 73, Price

Re: Topband: FT5ZM

2014-01-30 Thread ZR
Some of my best Antarctic area contacts have been with a horizontal antenna and the very best had the apex at only 50' and the end at 3blew the pileup away with one call and was told later at Dayton I was at least 10dB above the 10 KHz+ of callers. Not bad for a fast installed antenna at the

Re: Topband: Short receiving verticals question

2014-01-30 Thread Doug Renwick
I have used this same setup for my 4-square 160m receive array for years. Since I have to take down and put up this array every spring/fall, I have to re-tune each element for the 160m band. I have found that the base loading does not have to be exact for the system to 'work'. Last year I decided

Topband: oil-submerged variables

2014-01-30 Thread Pete Smith N4ZR
Thanks, everyone. I had not thought about the possible difference between 600M and 160 in terms of heating. Jon's suggestion of using big old micas sure seems like a good one if I can find what I need. As a refugee from the BC-610 era I'm amazed that any are still around! -- 73, Pete N4ZR Ch

Re: Topband: Submerging variable caps in oil as substitute forvacuum variables

2014-01-30 Thread Tom W8JI
Still I am intrigued by the thought of a remote tuning capacitor via hydraulic tubing :-). The capacitor plates could be as simple as two concentric cylinder conductors with appropriate spacers. I betcha crud collecting on the top of the oil would set voltage limit.>>> I would be as concerned,

Re: Topband: Short receiving verticals question

2014-01-30 Thread Tom W8JI
But what about an element loaded with a coil at the center or at the top? Would there be advantages to that approach that would come close to the short verticals with top-hat wires, or any serious disadvantages? Jon, The reason I use the hats and do everything I do in the elements is band

Re: Topband: Bad tower shunt capacitor

2014-01-30 Thread Don Beattie
Jamie, When I had a problem like that on a matching system, I had someone else key the transmitter and watched the feedpoint at night. It took ten seconds to see the problem ! Fireworks had nothing on what happened. 73 Don, G3BJ / G5W -Original Message- From: Topband [mailto:topband-bou

Re: Topband: Bad tower shunt capacitor

2014-01-30 Thread Jon Zaimes AA1K
Look closely and you may see a hairline crack on the bad one. Also look for other possibilities. A number of times I've swapped out "bad" matching capacitors without solving the problem, only to find later it was simply an oxidized connection that needed to be cleaned up and tightened down.