B
BOOTY MONSTER
Guest
nope , was just seeing if i was understanding homers results comparing the merlin to a 1/4 wave and a dipole so far . maybe i should have included that the "better" amount isn't much .......
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Homebrew Merlin Experiment
- Thread starter HomerBB
- Start date
nope , was just seeing if i was understanding homers results comparing the merlin to a 1/4 wave and a dipole so far . maybe i should have included that the "better" amount isn't much .......
If the weather holds I may be able to give that a whirl . . . If I can get the Merlin up high enough. Of course I can If I mount the V4k on the ground
I am unafraid . . .
Yesterday the longer was better at the same tip height. Today it may be different. Also, when I get the anlyzer settings for both right where I want them the ball game may change. . .
variables? I understand, but as for yesterday the biggest variable was
5/8 - one bar greater receive signal, better audio read, lower/quieter noise floor
Merlin - one bar lower receive signal, less readable receive, higher/noisier noise floor
B
BOOTY MONSTER
Guest
Fear had nothing to do with it...
You got it back? cool...
You have access to the antennas and thus have more control over at least some of those variables than I would while arm-char quarterbacking from my living room...
The DB
Perhaps a better word phrase would have been "i am fearless"
Actually, when I fixed the cold solder joint on the analyzer coax connector and tested it on the dummy load all was well.
Actually, when I fixed the cold solder joint on the analyzer coax connector and tested it on the dummy load all was well.
I would think that testing the Merlin against a standard 1/4w GP (@ the same feed point height) would be more appropriate . . .
It may come to that, Robb.
The thing is the models already give it a slight edge in that scenario.
When those who prefer the Merlin speak of its worth they say it dominated against everything from the A99 to the I10k. That is why I have been trying to test it against bigger antennas. I'm trying to see if it happens, and under what conditions it occurs.
Yesterday it was inferior to the 5/8 working both local and DX stations. On the other hand, today I would have to give the slightest edge to the Merlin. It isn't a full bar on my meter like yesterday, but clearly I have better receive on it, and on the transmit locally to two of three stations - one 7.5 miles out, the other 20 miles out. The third station is a mere mile away. Also, the noise floor is reversed today from yesterday - quieter on the Merlin instead of the 5/8 GP.
The local station 7.5 miles NW of me was using a EFHW homebrew six feet from the ground with no GP.
The station 20 mile north of me was using a 4 element Yagi turned NW. I was communicating vertically into his horizontal side. He said the receive for him was down slightly when I switched off to the 5/8 GP. Neither of them knew which antenna was which until we had sorted out the differences they were noting. I was having the same experience at my end.
I did QSO into W. Oregon on it working 3 watts PEP today. It takes no imagination to recognize that conditions were extraordinary during that DX window. The station in W. Oregon was working with a Proton99 100 feet in the air.
So far there hasn't been a dominance from the Merlin, but at times conditions do favor it. Of course, the Merlin is higher in the air from its feed point up. That's been the test point . . .
As for the 1/4 wave antennas shoot out, some users do not accept that this antenna is a 1/4 wave antenna, but believe it to be a 1/2 wave.
I believe it is what it is - 1/4 wave.
BTW, yesterday's weather here was bright and sunny, 66° F, and hardly a wind to speak of (note the photo posted above). Today a front has moved in, the temperature falling toward a chance of some rain tonight and snow by daylight in the morning. Currently it is 60° F, and headed to 26° F by tomorrow afternoon. This front has a wind with of 17 MPH and growing to 26 MPH by daylight.
Maybe something in this change accounts for the noise floor shifting.
The thing is the models already give it a slight edge in that scenario.
When those who prefer the Merlin speak of its worth they say it dominated against everything from the A99 to the I10k. That is why I have been trying to test it against bigger antennas. I'm trying to see if it happens, and under what conditions it occurs.
Yesterday it was inferior to the 5/8 working both local and DX stations. On the other hand, today I would have to give the slightest edge to the Merlin. It isn't a full bar on my meter like yesterday, but clearly I have better receive on it, and on the transmit locally to two of three stations - one 7.5 miles out, the other 20 miles out. The third station is a mere mile away. Also, the noise floor is reversed today from yesterday - quieter on the Merlin instead of the 5/8 GP.
The local station 7.5 miles NW of me was using a EFHW homebrew six feet from the ground with no GP.
The station 20 mile north of me was using a 4 element Yagi turned NW. I was communicating vertically into his horizontal side. He said the receive for him was down slightly when I switched off to the 5/8 GP. Neither of them knew which antenna was which until we had sorted out the differences they were noting. I was having the same experience at my end.
I did QSO into W. Oregon on it working 3 watts PEP today. It takes no imagination to recognize that conditions were extraordinary during that DX window. The station in W. Oregon was working with a Proton99 100 feet in the air.
So far there hasn't been a dominance from the Merlin, but at times conditions do favor it. Of course, the Merlin is higher in the air from its feed point up. That's been the test point . . .
As for the 1/4 wave antennas shoot out, some users do not accept that this antenna is a 1/4 wave antenna, but believe it to be a 1/2 wave.
I believe it is what it is - 1/4 wave.
BTW, yesterday's weather here was bright and sunny, 66° F, and hardly a wind to speak of (note the photo posted above). Today a front has moved in, the temperature falling toward a chance of some rain tonight and snow by daylight in the morning. Currently it is 60° F, and headed to 26° F by tomorrow afternoon. This front has a wind with of 17 MPH and growing to 26 MPH by daylight.
Maybe something in this change accounts for the noise floor shifting.
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Fear still has nothing to do with it...
So you know it is working well when attached to a dummy load... I know I know, had to say it...
The DB
Hey DB, we know you aren't afraid . . .
I'm just the one who has to say what I see as I see it. After all, I'm the fellow who put myself on the line for trying to run this test, so I feel I have an obligation to go out on a limb clearly calling what I see. I am wanting to be as wise as you are being by not nailing anything down prematurely.
I have gotten neither enough experience with this antenna, nor enough information to write a report card on it, yet. I have filled in the personal information on the front of the card, but the inside where the grades are is still a blank.
I will go ahead and make a fool of myself if I think that's what it takes to put the message down clearly. You guys can help me do it by asking all the questions, and challenging the parameters of my experiment. When it's done at least one of us will be satisfied with the grades on the report card.
I'm just the one who has to say what I see as I see it. After all, I'm the fellow who put myself on the line for trying to run this test, so I feel I have an obligation to go out on a limb clearly calling what I see. I am wanting to be as wise as you are being by not nailing anything down prematurely.
I have gotten neither enough experience with this antenna, nor enough information to write a report card on it, yet. I have filled in the personal information on the front of the card, but the inside where the grades are is still a blank.
I will go ahead and make a fool of myself if I think that's what it takes to put the message down clearly. You guys can help me do it by asking all the questions, and challenging the parameters of my experiment. When it's done at least one of us will be satisfied with the grades on the report card.
I respect anyone who is willing to learn by actually trying stuff. Anyone who isn't afraid of what others will think, and isn't afraid of getting potentially new information and criticism from people who are arm chair quarterbacking like myself. These people have earned my respect. Unfortunately we have to few like you in the world today. To many people who do published testing today (even if it only published to a forum) and post their findings to often have a bias, they have a dog in the race and want to see something specific happen. Strangely enough their test often shows what they want to see.
As far as challenging or questioning goes...
When it comes to angling radials down I'm not sure what we should call it. A vertical center fed ½λ dipole has specific properties, as does a ¼λ ground plane with its radials straight out. Anything in between it takes on properties of both to varying degrees, but does not neatly fit as either. I don't know that I would call any antenna that uses such a setup either a ¼λ or a ½λ antenna. Perhaps a hybrid of some sort as it, for better or worse, will have some properties from both.
The DB
Well, that is certainly a possibility - properties of both.
You may be right: it's a reasonable assumption.
The thing is 1/4ƛ GP antennas have been using droopy radials to fix the impedance at the feed point since who flung the chunk. It isn't a recent development, not with this antenna nor the one before it. Unless things have changed with respect to measuring omni antenna types the length of the vertical is what describes it.
On the other hand, not everything fits that profile exactly. There are electrical properties that can speak to this as loudly as the mechanical ones, like some 5/8ƛ antennas that are too short for 5/8ƛ and too long for 1/2ƛ - Maco V5/8 - or have too much length overall to be a 1/2ƛ in the usual mechanical sense - J-poles for example - and, of course, my personal favorite odd antenna out, the diminutive Astroplane.
Perhaps a model of an EFHW with radials overlaying the Merlin would be enlightening.
.50 wave radial effect pdf
Of course, either the EFHW in the above pdf would have to be lowered to the height of the Merlin, or the Merlin raised to the height of the EFHW
You may be right: it's a reasonable assumption.
The thing is 1/4ƛ GP antennas have been using droopy radials to fix the impedance at the feed point since who flung the chunk. It isn't a recent development, not with this antenna nor the one before it. Unless things have changed with respect to measuring omni antenna types the length of the vertical is what describes it.
On the other hand, not everything fits that profile exactly. There are electrical properties that can speak to this as loudly as the mechanical ones, like some 5/8ƛ antennas that are too short for 5/8ƛ and too long for 1/2ƛ - Maco V5/8 - or have too much length overall to be a 1/2ƛ in the usual mechanical sense - J-poles for example - and, of course, my personal favorite odd antenna out, the diminutive Astroplane.
Perhaps a model of an EFHW with radials overlaying the Merlin would be enlightening.
.50 wave radial effect pdf
Of course, either the EFHW in the above pdf would have to be lowered to the height of the Merlin, or the Merlin raised to the height of the EFHW
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Winds at the moment are 27 MPH gusting to 48 MPH. They will increase for the next two hours to 33 MPH and it is to be seen what the gusts will be. So far the antennas are still up and the SWR rock steady.
We shall see . . .
temps 31* w/wind chill to 14* I ain't working on anything outside today.
We shall see . . .
temps 31* w/wind chill to 14* I ain't working on anything outside today.
As you know, it was far too cold and windy today to be working on the antennas outside. Instead I went to work in the garage on the replacement full GP for the 5/8 antenna. While in the garage I was able to monitor the frequency - 27.385 LSB - for traffic and do some switching off between the two antennas for differences. They were back and forth, neck-to-neck today. A lot of fading and neither antenna as they are mounted (tip heights the same) could hold the prominent performance position for any consistent period of time.
Winds have been in the 25 to 35 MPH range with gusts in the 40 and 50 MPH range all day. Both antennas have held their SWR tightly despite that continuous treatment. Nothing looks bent or broken on either antenna. So good so far.
The progress on the GP is noted below in the photos. I am using a spreader assembly that resembles that of on a type used on a Quad. This make s it much easier to mount the radials. I can lean the antenna over, redo the GP set up, and then add the radials on at a time by sliding them into the spreader. I don't have to wrestle with 9' radials during the reconstruction.
Winds have been in the 25 to 35 MPH range with gusts in the 40 and 50 MPH range all day. Both antennas have held their SWR tightly despite that continuous treatment. Nothing looks bent or broken on either antenna. So good so far.
The progress on the GP is noted below in the photos. I am using a spreader assembly that resembles that of on a type used on a Quad. This make s it much easier to mount the radials. I can lean the antenna over, redo the GP set up, and then add the radials on at a time by sliding them into the spreader. I don't have to wrestle with 9' radials during the reconstruction.
B
BOOTY MONSTER
Guest
looks good homer . is that a cutting board in the middle ? iv'e had a few ideas about using them too . any idea how plastic cutting board react to UV rays ?
BTW , did your friend get you the measurements of his merlin yet ?
BTW , did your friend get you the measurements of his merlin yet ?