Homebrew Merlin Experiment

[gamegetter]

i put forward this question, did 55 really mean to include the AP, when he put forth his statement on the merlin out performing other antennas, i mean the AP was way out of production

and

I am trying to find the thread where marconi did some reiterations on an antenna for me, but I can't remember if it was the AP or other we were working on, it might prove valuable if I can find it. i'll post it if find it.

good day

 

[HomerBB]

Doc, I don't know of 55 making that claim.
Booty, the AP has no more delicate parts than the Merlin. In fact, my homemade did not have a PL239, but was directly attached to the antenna via terminals.
Gamegetter, I am not sure which thread what you're looking for is own . . .

 

[gamegetter]

Doc, I don't know of 55 making that claim.
Booty, the AP has no more delicate parts than the Merlin. In fact, my homemade did not have a PL239, but was directly attached to the antenna via terminals.
Gamegetter, I am not sure which thread what you're looking for is own . . .

ok, i found the thread it was related to the imax ground plane radials at various angles,,,so it was a different antenna. However later on in the thread we looked at different models related to elevations.

http://www.worldwidedx.com/cb-anten...nec5-model-imax-radials-various-angles-3.html

 

[HomerBB]

glad you found it. i looked around but came up empty.

 

[Marconi]

gentlemen, i went back and read the thread where we discussed the astroplane at length back in May and found that the last model showed the astroplane modeled at 48' had a 3.72 dbi.

http://www.worldwidedx.com/cb-anten...-astroplane-vs-new-top-one-per-eznec5-15.html

Thanks gamegetter for looking back, but don't consider the model above as being fair, equal in features or settings with the Merlin I just posted.

In my post #36 above, I tried to explain some of the problems I'll have getting this comparison work done quickly. I did not think it fair, in this case, to just pull out any old AstroPlane file and compare to the Merlin...or I would have surely done just that.

The Merlin models I just posted have no masts, and the A/P file you link us to has a mast in the model. This alone can make a noticeable difference in gain for the model.

I worked on this project today, but I need some more time.

 

[gamegetter]

roger that marconi,,,

 

[gamegetter]

i put forward this question, did 55 really mean to include the AP, when he put forth his statement on the merlin out performing other antennas, i mean the AP was way out of production

and

I am trying to find the thread where marconi did some reiterations on an antenna for me, but I can't remember if it was the AP or other we were working on, it might prove valuable if I can find it. i'll post it if find it.

good day

regarding my first question above, i went back to BM's post #2 and found where 55 clearly states that he claims the merlin to be better than most antennas on the market "today". i don't know for sure but i don't think he was thinking of the AP when he wrote that claim.

just thought i would put that out. does not mean we can't compare it to the AP, i am interested now.

 

[HomerBB]

Looking forward to it.

 

[BOOTY MONSTER]

marconi , why do you sometimes leave the mast out of your models ? wont most installs have a mast or ground wire running down to the ground ?

 

[Marconi]

That is a good question BM. I usually include the mast in my models, but I also realize a mast is just another consideration that can ill-affect how an antenna design works, and it can show up in the antenna results.

If you look back at other models done by many of the antenna gurus on the Internet, you will probably find, if you can tell, that they hardly ever include the mast in their models. Most of the time you won't even know if there is a mast or know how high the model is set. All of that can be important.

When I first did my Merlin, sometime back, I did not include the mast. The other day when Homer made this thread I opened the model and just went from there. I posted it just to go along with my showing him the feed point similarity in an image I got from Cajun. I never thought we would be comparing the Merlin to the A/P either.

The problem arises now that the A/P requires a mast to make a good match and work as intended. The Merlin models I have are absent the mast. Not a really good approach for a fair comparison.

I still don't have the true Merlin dimensions, and the top part is just my best guess-ta-mation, so this all may be a vain effort.

I think I have completed the comparison work and got the two models close to the same settings for accuracy and the segment count, but I still want to study the results a bit more.

Homer, you're going to be surprised at the results so far. I know I am. Be aware too, that these Merlin models still have their ground plane radials set at about 40* degrees, and I suspect that when I bring them down some more closer to 20*< degrees, the gain will improve. This of course assumes that the match does not go to heck in a hand basket.

I the Merlin even compares close to my Starduster, then this recap report I did in the spring of 2011, probably suggest why.

View attachment Signal Recap 2011.pdf

 

[W5LZ]

"I still don't have the true Merlin dimensions, and the top part is just my best guess-ta-mation, so this all may be a vain effort."
If the models are not accurate then the information from those models can't be accurate either. I agree with you that your information is only a 'guess-ta-mation' and should only be taken as such.
I would think that should be fairly easy to correct. Simply have someone measure the antenna. If someone who already has one doesn't want to take it down to measure, I can certainly understand that. So how about having someone who has just purchased one keep notes (accurate ones) on it's assembly? Surely someone would be willing to do that?
- 'Doc

 

[BOOTY MONSTER]

the same would apply to homers "copy" too Doc , to some degree .

 

[Marconi]

"I still don't have the true Merlin dimensions, and the top part is just my best guess-ta-mation, so this all may be a vain effort."
If the models are not accurate then the information from those models can't be accurate either. I agree with you that your information is only a 'guess-ta-mation' and should only be taken as such.
I would think that should be fairly easy to correct. Simply have someone measure the antenna. If someone who already has one doesn't want to take it down to measure, I can certainly understand that. So how about having someone who has just purchased one keep notes (accurate ones) on it's assembly? Surely someone would be willing to do that?
- 'Doc

Well 'Doc, you don't know these guys that own the Merlin very well. They wouldn't answer questions, and I would depend on my guess-ta-mation long before I would believe one of these particular guys anyway.

Questions have been asked several times.

 

[HomerBB]

There is a friendly Merlin owner who will provide me with the dimensions of the CH, and will measure his coil.

As it stands his memory says it is
CH = 24"
coil - 6" diameter

other measurements were, according to one of the owners post on another forum,

101" for each radial
72 - 73 inches for the vertical, or until the tune gets right.
Hopefully I can get a definite verification on the CH and Coil today.

 

[BOOTY MONSTER]

don't forget to ask him to check the distance between the coil and the capacity hat , the length between the bottom and top of the coil , and the distance away from the mast the bottom tips of the ground elements are .