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Messages - KE7TRP

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16
Antennas / Re: Double Bazooka antenna plans
« on: July 29, 2013, 11:33:34 AM »

17
This test is a 40 meter Double Bazooka wire antenna made from RG11 coax VS an 80 meter open wire line doublet.  The Doublet is from Trueladderline.com and uses 600 ohm feedline. The antenna is hooked to a Johnson KW matchbox balanced tuner. The Doublet is at 40 ft.  The Double bazooka is at 30 ft.  The DBZ has a lot less noise with stronger signal than the Doublet.


I took this video today.

http://youtu.be/_nWCGKyOSqk


18
Antennas / Re: Double Bazooka antenna plans
« on: July 26, 2013, 10:19:34 AM »
I got the 40 meter DBZ installed.  I compared this to my 80 meter open wire line fed doublet yesterday. Both close to same height.  On 40, The 80 meter open wire line antenna has gain.  About 3 DB according to EZnec. I am using a Johnson KW matchbox with the open wire line.

Base line noise level is approximately 4 to 5 DB lower on the DBZ. I used my SDR pan adapter to show the static noise at various frequency's across the band.   

Peak signals from Foreign Broadcast where exactly the same. I could not prove one was better than the other. I then proceeded to make a page of 40 meter contacts across the US. Not one station reported one was better than the other.  I could switch between words with NO delay.  Over the course of the day, stations just reported that they are the same.

The SWR on the analyzer shows 1.0/52 ohms at 7200 where I set it.  Its under 1.5 across the entire 40 band.  No tuner needed.   

The 40 DBZ does not come over the Home theater.

Looks like a great antenna for 40 meters.

C

19
Antennas / Re: Double Bazooka antenna plans
« on: July 25, 2013, 08:57:26 AM »
Thanks for posting Paul. Yes, We do not have an antenna range. I wish we did. However, We can compare antennas at home.  That's a great part of the hobby that I enjoy.

I only had one antenna up at a time.  The second antenna was in a pile under the tower between tests.  I tested 4 times back to back.  In all cases, my chart has reports of higher signal on the DBZ. My Chart shows higher RX signal that is in line with the gain in TX.  I would not have believed this if I was not there.  It really makes no sense to me as the Open wire doublet should have next to no loss through a balanced tuner.  However, There must be some loss somewhere or the patterns are such that in state contacts suffer on the doublet. 

I think once I do my tests over a 2000 mile distance, we will have more data.  Its possible that the Doublet has a strong vertical component.  If so, Then this all makes sense. The close in under 500 mile contacts are going to be better on the DBZ.  More of an NVIS pattern.

Using a Field strength meter at 25 watts AM carrier there is no detectible RF on my Feedline of the DBZ. On the OWL, of course the meter pins near the feedline.  I have current meters on each leg of the doublet and It is in balance with in a % or so.  Even then, You do have some RF off the OWL.

The DBZ does not come over the home theater which is a great plus in my household.  I think this is because the DBZ is not radiating over the feedline and causing the interference.  There is also the idea that the OWL with balanced grounded tuner, Is using the HOUSE wiring as a counterpoise.  Hence, The home theater turns into a public address system.

I was going to run some more tests today but woke up to pouring rain.

C

20
Antennas / Re: Double Bazooka antenna plans
« on: July 24, 2013, 07:42:54 PM »
I got my 75 meter DBZ up today.  Mine is made from RG11 coax.  I am not getting the bandwidth I wanted.  I can go from 3715 to 3915 under 2 to 1. Not the whole band.  I am using 100ft of Brand new LMR400 for the feedline that then runs into 100 FT of half inch hard line.  Tomorrow I will run the LMR into shack so I will remove 100 FT of feedline. 

The tests ran tonight where back to back. It took me 2 minutes running to lower 80 meter Open wire line antenna and put up DBZ.

The setup:


55ft crank up tower set at 40 ft due to monsoon season.
Antenna 1 = 126ft open wire line doublet (True ladder line dot com) to a Johnson matchbox balanced tuner. 40 ft
Antenna 2 - Double bazooka made from RG11 coax fed with LMR400. 35 ft

5 stations on the air ranging from 15 miles to 400 miles..  NOBODY knew which antenna I was on. Only Antenna 1 and antenna 2.

In all cases the DBZ BEATS the Doublet.  I am in shock.  I would have bet money the open wire doublet would win.  Reports are 3 to 6 DB.  I see 6 DB lower baseline noise on my band scope with the DBZ. But 3 to 6DB higher RX. 

Keep in mind I ran out and switched the antennas back and forth and did the tests 4 times.

NOT one station said Antenna 1 was better.  NOT one station was higher on RX then Antenna 2.

The DBZ on these state side contests wins with out question.  Now to ponder why.  There nothing much more efficient that 600 ohm open wire line to a doublet with a balanced tuner.

Tomorrow I will remove the 100 Ft section of hardline and run just the LMR400.  I will also put the DBZ at 40 ft.  Then, I will adjust it for 75 meters. The Low point is 3800 where I would like 3900.

The best part of all of this?

With the Open wire line doublet, If I ran 100 watts, I would blast over the Home theater.  With the DBZ, I can run 100 watts and not cover over the theater at ALL.  In fact, I can run up to 500 before I just start to hear my signal over the speakers. 

Hmmm.   I had a lot of fun with these tests.   More to come.


22
General discussion (QSO) / HAARP shuts down
« on: July 21, 2013, 12:39:43 PM »
No more HAARP.  Article from ARRL:


http://www.arrl.org/news/haarp-facility-shuts-down

23
Antennas / Re: Antenna options for those living in apartments
« on: July 21, 2013, 08:29:20 AM »
I live in an apartment with outside garage.  I have few grounding options, and desire ideas.  Thanks! :)


What bands where you planning to use?    I recently tested an end fed antenna called the "end fed easy tenna".  I got the 54 ft version.  I ran battery power with an FT450 yaesu.  I worked pages and pages of contacts on 10, 15,17,20 and even talked to state side friends on 80 meters.  All with 30 watts or so.

C

24
AM Transmitters / Re: WA2ROC Studio A
« on: July 20, 2013, 01:53:32 PM »
Very nice station!   I love that combo. I used to have a decent NC300 with the outboard Converter and speaker. I sold it off. Maybe I will find a very nice one some day or maybe a 303.

Good info on the loop. I wish I had room here.  That sounds like the way to go.  I do have some pines but the loop would be closer to all the neighbors so I think for now, I will keep the doublet. I enjoy trying antennas and testing them. I plan to try a couple different antennas soon. Its just so darn hot outside here in the summer!

25
Software Defined radio (SDR) Forum / Re: RealTech - The Cheap SDR
« on: July 15, 2013, 11:31:04 AM »
I got my Nooelec R820T today.  The install instructions are garbage.  After about a half hour, I got the driver to install and the SDRsharp program working.  FM radio works great.  I have not heard much else so far.  I guess I will try listening to 2meter Ham next.  Are there any other frequencies or ranges I might want to try out?

BTW..  Nooelec has horrible customer service.  It took 14 days to get my package after I paid for the 2 day shipping.  When questioned, the woman raised her voice at me and started on the defense.

26
Antennas / Re: Double Bazooka antenna plans
« on: July 15, 2013, 08:34:33 AM »
The bad press on the bazooka comes from a foreign ham who ran tests on dipole vs his homemade bazooka.  His tests show a major loss in performance and in short, Slammed the antenna.  Ham read this and just parrot what he wrote.  I try to run my own tests here and will as soon as I get my antenna up in the air. I plan a back to back test with two antennas up at the same time. 

Recently two stations I know switched from wire to the bazooka and both have stronger signals here and they don't have to use the tuner anymore.  If this antenna does not work as well as my wire, I will report it and I will find the drawback. 

C

27
Antennas / Re: Double Bazooka antenna plans
« on: July 12, 2013, 09:45:46 AM »
I agree Paul.  I enjoy working with antennas and plan to try a few different styles.  I just wish it was not july in Arizona.. Its to hot to even go outside, yet alone, work on an antenna.

C

28
Antennas / Re: 40 and 80 meter wire dipoles... How far apart?
« on: July 12, 2013, 09:44:08 AM »
I am familiar with Fan dipoles.  Around here they are called Maypole antennas.  That's a great option and one I might test some day. Two wires for 40 and two for 80.   I am not sure you can make a bazooka style antenna in this fashion.  I really need to test this out.   

Currently,  I have 600 ohm open wire line from either a KW matchbox or a HB tuner in the shack.  The 600 ohm line runs out of the shack and then through two large inductors to ground for static discharge.  Then, the open wire line runs up the tower to a fiberglass stand off that is 3 feet off tower.  The open line splits off to 130 ft of wire in an inverted V.

C

29
General discussion (QSO) / Re: Uh Oh Another New Guy
« on: July 11, 2013, 06:05:48 PM »
Hi  David.  Thanks for joining the forums.  I am sure everyone will really enjoy reading your website.  Thanks for the info on the DBZ!

C

30
Antennas / Re: Double Bazooka antenna plans
« on: July 10, 2013, 08:14:50 AM »
I agree.  There is no free lunch Doc. 

What do you think about the loss of say a standard 80 meter dipole stretched to cover the entire band using a typical T match tuner, VS, having the Bazooka antenna with no tuner?

A typical dipole will have 150 KC of usable bandwidth before you must go to the tuner.   

I enjoy experimenting and testing out different antennas so its all fun to me!


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