EZNEC help please

[Crawdad]

Looks like you have it dialed in perfectly. I used a hairpin match on my 6m yagi as well. I used a halfway coaxial balun along with it and the match was similar to what you show. My configuration is six elements on a 17 foot boom but it an OWA design...... Optimal Wideband Array......so it just fits in that 17 foot boom. Reflector to driver spacing is only about 27 inches and driver to the first director is about 16 inches. This assures heavy coupling and creates a nice tight pattern on a 17 foot boom. I used an old Wilson Shooting Star for parts so it is really heavy duty for 6m.

This is my first Yagi build and my goal is to get a bit more gain over the Moxon I use now while making the antenna as lightweight and low wind load as possible. It won't be very wide-banded since all I'm interested in is the SSB portion of the band. As of now the boom will only be 82" long.

If the final numbers are anything close to the model, I'll be as happy as a pig in you know what.

7 3

 

[BJ radionut]

I'll add this in regard to design...You build for MAX forward gain.
I qualify with this...Good Back Scatter on 6m is a plus IMHO. I can think of only a handful of times where I wanted to reject/attenuate someone's signal on 6 meters (after 15 yrs on 6m)...Plenty of band space ...I'll move (or they will!!!) Just saying... Forward Gain...forget the back door/ 90+ times out of 100 you want to hear back scatter

 

[BJ radionut]

I also add this...IF I was CK...build for rejection...because those guys on coast have a hard time hearing when they have a thousand A$$holes like me behind them....

 

[Crawdad]

I'll add this in regard to design...You build for MAX forward gain.
I qualify with this...Good Back Scatter on 6m is a plus IMHO. I can think of only a handful of times where I wanted to reject/attenuate someone's signal on 6 meters (after 15 yrs on 6m)...Plenty of band space ...I'll move (or they will!!!) Just saying... Forward Gain...forget the back door/ 90+ times out of 100 you want to hear back scatter

I'll play some more and see how high I can get the gain. Other than local noise, which isn't bad, I don't have anything I need a big F/B for.

 

[Crawdad]

Just saying... Forward Gain...forget the back door/ 90+ times out of 100 you want to hear back scatter

This is as much gain and as low F/B as I could squeeze out while keeping within my weight and boom length limits.
The dBref gain is Free Space dBi minus 7.55 dB which is the Driven element gain modeled over the same height and over real ground as the Yagi was modeled.

After playing with the Hairpin dimensions:

It's been fun playing with and learning the basics of EZNEC. It will be interesting to see how close to real life the modeling dimensions turn out to be.

7 3

 

[Captain Kilowatt]

I also add this...IF I was CK...build for rejection...because those guys on coast have a hard time hearing when they have a thousand A$$holes like me behind them....

QRZ? Sorry OM but you are 3x4, 3x4 and down in the mud. Barely copy you. Say again please.

 

[Crawdad]

QRZ? Sorry OM but you are 3x4, 3x4 and down in the mud. Barely copy you. Say again please.

Ouch

 

[BJ radionut]

Your 22...22... rifle shot 22... OVER

...Check...Check...good contact!

 

[Captain Kilowatt]

I also add this...IF I was CK...build for rejection...because those guys on coast have a hard time hearing when they have a thousand A$$holes like me behind them....

Actually Gary, I haven't used that antenna for a number of years now but it had a great pattern. I could listen to a baby monitor on 49.830 MHz up the road at S9+20 on the front and it would drop to S2-3 on the rear corner. It has a really good pattern for rejecting the rejects.I hope to get it back up this summer.

 

[BJ radionut]

Evan: I think those look pretty damn reasonable numbers...15+ dB F/B and Side/Front and 6+ dB forward gain...
Yes, interesting to see how it works out.
Keep good notes/pictures etc... this would make a great thread ...6m Featherweight 3 "L" Yagi revised!!!

 

[BJ radionut]

Actually Gary, I haven't used that antenna for a number of years now but it had a great pattern. I could listen to a baby monitor on 49.830 MHz up the road at S9+20 on the front and it would drop to S2-3 on the rear corner. It has a really good pattern for rejecting the rejects.I hope to get it back up this summer.

Yes...Life gets in the way...Age has diffidently slowed my antenna experiments down also...I have
40ft Rohn 25G...H/D tilt base plate...
Top plate w H/D thrust bearing...
Tailtwister II rotor...
And whole S**T load of antennas I could load on it...been in the barn since my last neck surgery (5yrs ago)

I will get some 2m gear up this spring (12 element wide space) ...Cherry Picker rental for couple days ...I can do that

 

[Captain Kilowatt]

Yes...Life gets in the way...Age has diffidently slowed my antenna experiments down also...I have
40ft Rohn 25G...H/D tilt base plate...
Top plate w H/D thrust bearing...
Tailtwister II rotor...
And whole S**T load of antennas I could load on it...been in the barn since my last neck surgery (5yrs ago)

I will get some 2m gear up this spring (12 element wide space) ...Cherry Picker rental for couple days ...I can do that

I need to take my 64 foot Trylon T-500 down and convert it to a tilt over base. No small feat. The bottom section is 42 inches wide and total weight is just over 1000 pounds without anything on it. Add at least another 200 pounds for the mast and antennas.