Recent Posts

Pages: [1] 2 3 ... 10
1
Radio / A Tue Multi-band Antenna (80-10 Meters)
« Last post by JohnyMac on Today at 12:57:29 PM »
I have been shopping for a new G5RV type antenna since Radio Works in VA. was sold. I currently have one running east-west (North south lopes) and I wanted one that goes north-south (west-east lopes). The new owner is focusing his production in a different direction than the G5RV right now. What it comes down to, is for me to make my own G5RV antenna.

Knowing that some of you are working on new antenna's over the winter I thought I would share this with the folks here.

Now many folks carry manufactured G5RV antenna's and market them as multi-band antenna's when in fact they are not. They are weak on 75/80 and 10-meters and will not pick up 60, 30, and 15 meters. Eventually my search lead me to reading an article entitled, The Truth about the G5RV Antenna.

The article spoke to two different versions of the G5RV antenna - The ZS6BKW and W0BTU Antenna's. As it is tough in life to get an all encompassing piece of equipment ala "getting your cake and eating it too", both the ZS6BKW and W0BTU antenna's are an improvement over the G5RV antenna however, neither one is all encompassing.

Because I hate wasting my time, and prefer doing something once rather than twice, I contacted Cecil Moore, W5DXP who has reportedly made some considerable improvements to the ZS6BKW and W0BTU antenna's.

Moore and I have been trading emails over the past few months and he just published an article entitled How to Transform Your ZS6BKW Into an All-HF-Band Antenna.

In essence the antenna is a dipole flattop 92' long with 39' of 450 ohm ladder line into a 1:1 choke-balun to 50 ohm coax. If you just did this your SWR's (Standing Wave Ratio) would be the following in the following band's:

Meter      SWR
80           4.5*
60           >10**
40           1.4
30           >10**
20           1.3
17           1.4
15           >10**
12           1.2
10           1.6

If you don't want to have to use a tuner you really want to keep SWR below 1.5. If you use a tuner to control SWR lets say taming a high SWR, there is no tuner I am aware of that will bring an antenna's SWR down south of 2.0 if the SWR is north of 10.0.

*   You will need a tuner
** You can not tune

These results bring us to Option 1.

Option 1:

To bring 80-meters down to 1.2 SWR add a 500pf Doorknob capacitor*** post the 1:1 balun on the center coax center conductor. When you do this the SWR on 80-meters drops to around 1.2. The capacitor does not adversely affect SWR when left in line to 40, 20, 17, 12, & 10-meters.

*** Leaving the capacitor in line does not adversely affect the higher frequencies when you add ladder line as described in Option 2.

Option 2:


What can you do to optimize 40, 20, 17, 12, & 10-meters after adding the capacitor for 80-meters is to add/delete 450 ohm ladder line in 1 or 2-foot lengths. An easy way to do this without manually adding/deleting ladder line using banana clips, is to use a DPDT knife switch. By adding one or two feet to the existing 39-feet of ladder line helps SWR in the 40, 20, 17, 12, & 10-meter bands with the capacitor still in line.

Here are the SWR's for the following frequency's with an inline capacitor and by adding 1-2-feet of ladder line to the original 39-feet of ladder line via the DPDT knife switch.

Meters  SWR           Configuration
80         1.2                500pf capacitor & original 39' Ladder line   
60         >10**
40         1.5                500pf capacitor using knife switch add 1' ladder line
30         >10**
20         1.0                500pf capacitor using knife switch add 1' ladder line
17         1.4                500pf capacitor original 39' ladder line no additions
15         >10**
12         1.2                500pf capacitor using knife switch add 1' ladder line
10         1.8                500pf capacitor using knife switch add 2' ladder line

Option 3:

By using options 1 & 2 combined, SWR is great except for 60, 30, and 15-meters. Now we get into a bit more complicated procedure as it involves a couple more knife switches, a relay switch, and some additional capacitors (60-meters a 128pf, 30-meters 104pf, 15-meters  44.5pf). If you execute on this last procedure you will in fact have a true multi-band antenna from 80-10-meters.

This is what the SWR looks like for 60, 30, & 15-meters.

Meters  SWR             Configuration
80           1.2                Capacitor & original 39' Ladder line   
   60       1.5               Using knife switch add 2' ladder line PLUS using relay switch add 128pf capacitor
40           1.5                 Using knife switch add 1' ladder line
   30       1.1               Using knife switch add 2' ladder line PLUS using relay switch add 104pf capacitor
20           1.0                Using knife switch add 1' ladder line
17           1.4                Original 39' ladder line no additions
  15        1.0               Original 39' ladder line PLUS using relay switch add 44.5pf capacitor
12           1.2                Using knife switch add 1' ladder line
10           1.8                Using knife switch add 2' ladder line

Please take the time to read both articles as they do much more justice than my short explanation does complete with PICTURES and GRAPHS.

With deer season ending for now, and my outside projects coming to a close do to weather, I will build this antenna and document all of my moves. Once done I will hoist and let you know how it works.

73!


 

2
General Discussion / Re: Macron Is In Deeper Than I Thought
« Last post by gadget99 on Today at 12:53:06 AM »
Thanks for the info.  I was beginning to think there might actually be something going on with this.

Nemo

The potential exists for this to bring changes in the government. So we can wait and see.

Small changes in policy are the likely response.

Ground swelling and sweeping changes as a result of this stuff is very unlikely.

Something that is not reported on in the MSM is the standards of living in the Prime EU countries is VERY high. The populaces have very little to complain about. So when they do it grabs media attention BIG time. That can paint a confusing picture about the current state of affairs.

Contrary to popular belief at this time. The EU is still in a healthy condition and looks to be in little danger of dissolving. While not perfect and plagued with some problems. It is still one of the largest and most robust Trade Unions in existence today.

I will keep an eye out as time goes on. Anything is possible.

Cheers
3
General Discussion / Re: Macron Is In Deeper Than I Thought
« Last post by Nemo on December 08, 2018, 05:17:45 PM »
Thanks for the info.  I was beginning to think there might actually be something going on with this.

Nemo
4
General Discussion / Re: Macron Is In Deeper Than I Thought
« Last post by gadget99 on December 08, 2018, 07:40:05 AM »
I forgot to mention that the act of rioting about the slightest little thing has been woven into the French culture since the French revolution.

Then again there is something like that here in the UK.

You should see the mass brawls that happen over here at some soccer matches. Freaking unbelievable.

5
General Discussion / Re: Macron Is In Deeper Than I Thought
« Last post by JohnyMac on December 08, 2018, 07:35:11 AM »
Interesting gadget. Thx for the on scene report.
6
General Discussion / Re: Macron Is In Deeper Than I Thought
« Last post by gadget99 on December 08, 2018, 07:33:08 AM »
Hi all,

Thought I might chime in a bit on this.

A few items to concentrate on for perspective.

The people that are demonstrating are the French equivalent of college snowflakes in the US.

Take a look at the numbers being reported. In the grand scheme of things we are talking small numbers. When the number of police on the scene out number the protesters. Then we are talking about bring elements.

Think dumb ass people like ANTIFA.

Not saying there are not issues in France and the EU that need delt with.

Just saying this is not an Arab Spring type of thing at the moment.

Cheers all
8
General Discussion / Re: THE SOUTH AFRICA THREAD
« Last post by Nemo on December 07, 2018, 08:22:41 PM »
I presume the money is in South African Rand (ZAR) and that 404,201 is only $28,493 USD.

Hail, some CEOs here make that in a day or half a day. 

But its still a big freaking lot to me in ZAR or USD numbers. 

Nemo
9
Health / Re: Ebola Update - October 2018
« Last post by patriotman on December 07, 2018, 07:33:11 AM »
Quote
The second-largest Ebola outbreak in history has spread to a major city in eastern Congo, as health experts worry whether the stock of an experimental vaccine will stand up to the demands of an epidemic with no end in sight.

Butembo, with more than 1 million residents, is now reporting cases of the deadly hemorrhagic fever. That complicates Ebola containment work already challenged by rebel attacks elsewhere that have made tracking the virus almost impossible in some isolated villages.

“We are very concerned by the epidemiological situation in the Butembo area,” said John Johnson, project coordinator with Medecins Sans Frontieres in the city. New cases are increasing quickly in the eastern suburbs and outlying, isolated districts, the medical charity said.

The outbreak declared on Aug. 1 is now second only to the devastating West Africa outbreak that killed more than 11,300 people a few years ago. There are currently 471 Ebola cases, of which 423 are confirmed, including 225 confirmed deaths, Congo’s health ministry said late Thursday.

Without the teams that have vaccinated more than 41,000 people so far, this outbreak could have already seen more than 10,000 Ebola cases, the health ministry said .

This is by far the largest deployment of the promising but still experimental Ebola vaccine, which is owned by Merck. The company keeps a stockpile of 300,000 doses, and preparing them takes months.

“We are extremely concerned about the size of the vaccine stockpile,” WHO’s emergencies director, Dr. Peter Salama, told the STAT media outlet in an interview this week, saying 300,000 doses is not sufficient as urban Ebola outbreaks become more common.

Health workers, contacts of Ebola victims and their contacts have received the vaccine in a “ring vaccination” approach, but in some cases all residents of hard-to-reach communities have been offered it. The prospect of a mass vaccination in a major city like Butembo has raised concerns. Salama called the approach “extremely impractical.”

A WHO spokesman said shipments of doses arrive almost every week to ensure a sufficient supply for the ring vaccination. “No interruptions of vaccine supply have occurred to date,” Tarik Jasarevic said in an email to The Associated Press. “Merck is actively working to ensure sufficient number of doses continue to be available to meet the potential demand.”

This Ebola outbreak is like no other, with deadly attacks by rebel groups forcing containment work to pause for days at a time. Some wary locals have resisted vaccinations or safe burials of Ebola victims as health workers battle misinformation in a region that has never encountered the virus before.

A “fringe population” has regularly destroyed medical equipment and attacked workers, Health Minister Dr. Oly Ilunga Kalenga told reporters on Wednesday.

The Ebola virus is spread via bodily fluids of those infected, including the dead.

The outbreak “remains serious and unpredictable,” the World Health Organization said in an assessment released Wednesday. Nine health zones have reported new cases in the last week, and some have been unrelated to known victims, meaning that gaps in tracking remain in a region with a dense, highly mobile population.

Thousands of people have been organized by Red Cross societies and others to go house-to-house dispelling rumors and checking on possible contacts of victims.

Dr. Fatoumata Nafo-Traore, Africa regional director for the International Federation of Red Cross and Red Crescent Societies, joined one awareness campaign in the outbreak’s epicenter, Beni, this week.

The head of one family thanked her for the face-to-face contact, saying he didn’t even have a radio and didn’t understand what was happening. “Ignorance is the enemy,” another resident said.

Given the years of conflict in eastern Congo, it’s essential that households trust why the health workers are there, Nafo-Traore told the AP.

While she called the insecurity “very worrying,” she said that with new tools at hand, including vaccines, “there is great hope.”



https://www.apnews.com/86fd89fa73594ed0aa098c6c5a063300
10
Sustenance / Re: A few food Videos
« Last post by Currahee on December 07, 2018, 07:17:18 AM »
Nice! thank you for posting these.

Couple more coming in the series
Pages: [1] 2 3 ... 10