| Author |
Message |
    
Johnhenre
Intermediate Member
Username: Johnhenre
Post Number: 105
Registered: 1-2004
| | Posted on Thursday, April 30, 2009 - 4:32 pm: | 
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I READ A LOT ON THE ANTENNA TOPIC BUT CANT FINE OUT WHAT I NEED TO KNOW BUT IF SOMEONE IS OR USING TWO MACO M107 BEAMS CO PHASED TOGETHER,AND ANY HELP I'D APPRECIATE THIS INFORMATION BOB |
Bruce
Senior Member
Username: Bruce
Post Number: 5026
Registered: 9-2003
| | Posted on Thursday, April 30, 2009 - 8:39 pm: |
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WHY?
Why would you need anything that big ?
That's one big antenna .... seems to me from all my years on the radio anything much over 4 elm is overkill .....
Just my opinion ......
On 6 since 66
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Johnhenre
Intermediate Member
Username: Johnhenre
Post Number: 106
Registered: 1-2004
| | Posted on Friday, May 01, 2009 - 12:21 am: |
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I YOU COULD SEE THE DB GAIN OF ONE M-107 COMPARED TO LIKE MAY MOON RAKER 4'S IN AND OUT MYBE YOU COULD UNDERSTAND WHAT I'M SEEKING NEVER LESS I'VE SPENT A WHOLE WHOLE LOT OF WASTED MONEY ON EVERY GROUND PLANE THAT WAS EVER BUILT BEGANING IN THE 60'S INCLUDING EVER BEAM THAT WAS BUILT.BUT HAVE COME TO THE CONCULSION THAT A 7 ELEMET IS THE BEST WHAT EVER ONE SAY ALSO SELLS DB GAIN IS DB GAIN AND YOU CAN HEARD AND TALK IT ON A 3 WATT RADIO. MOSTY WITHOUT CONDITIONS.AND I FORGOT TO INCULDE YAGI AND GUNS OWNED THEM TO JUST LIKE TO KNOW IF ANYONE HAS ATTEMPT TO CO PHASE TWO M-107'S AND HOW THEY ARE WORKING I'M SURE IF YOU ONLY WORK ONE 107 YOU UNDERSTAND WHAT I'M SAYING THANKS IF SOMEONE HAS MORE INFO. AND I'M NOT DOWNING ANY ANTENNA THAT YOU GUYS OPERATE ON ITS JUST (I'VE) BEEN THERE, BOB |
Bruce
Senior Member
Username: Bruce
Post Number: 5029
Registered: 9-2003
| | Posted on Friday, May 01, 2009 - 5:30 am: |
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A moonraker would be about ONE S UNIT LESS than stacked 7's and MUCH less weight. On a band like 11 meters that moon raker 4 is one good antenna ....... so it boils down to do you want to spend upwards of $1300 to gain ONE S UNIT ?
DON'T BELEVE THE GAIN THAT YOU READ ABOUT ON MOST ANY ANTENNA .... the fact is that gain is a function of boom length and the number of elements..... Normal gains is about 6 DBD for a 3 elm beam so a 7 would run about 4 DBD more...
( On the M-107 you have a Boom Length of 37.5foot so you’re looking at about 11 DBD ( 13.5 DBI ) gain and maybe 14 DBD ( 16.5 DBI ) gain for 2 of them stacked
This is the real world ....
Now on higher bands like 2 meters stacked 7 elm beams makes sense
On 6 since 66
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Captian_radio
Advanced Member
Username: Captian_radio
Post Number: 556
Registered: 9-2004
| | Posted on Friday, May 01, 2009 - 12:06 pm: |
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Try a smaller antenna at a greater height.I used to have a 6 element homebrew yagi for 10 meters and it worked great, espically on the really long haul stuff into Asia etc.If you go higher with your antenna it will lower the take off angle therefore making the antenna more effective for longer haul dx
Bob
Robert L. Spicer The days of radio are just beginning!
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Patzerozero
Senior Member
Username: Patzerozero
Post Number: 4534
Registered: 7-2004
| | Posted on Sunday, May 10, 2009 - 5:30 pm: |
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actually, bruce, i think johnhenre is totally incorrect, too. he should be looking to stack m108's. why waste all that effort & not go all the way  .....gyzmotchy sells an add-on director kit, could always stack 20 element gyz's...... |
Keithinatlanta
Advanced Member
Username: Keithinatlanta
Post Number: 827
Registered: 3-2003
| | Posted on Monday, May 11, 2009 - 7:20 am: |
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In reading this topic, it brings to head a question regarding length of coax. How long can you go with coax before you start losing signals or raising SWR's? Maybe there is no magic answer. I just have always wondered if you would lose signals due to too long a length of coax. Thanks.
Keith in Atlanta
CEF 150 |
Bruce
Senior Member
Username: Bruce
Post Number: 5059
Registered: 9-2003
| | Posted on Monday, May 11, 2009 - 5:56 am: |
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PAT .....
I ran QUAD STACKED 17 elm KLM's on 2 meters in the 70's for MOONBOUNCE ......
Would I do it again ?
You bet and run a KW to use our local repeater ...
This makes about as much sence ..... and I'm kidding too .....
The law of return for what you put up goes down fast past 4 elm beams. Wind load and weight will cause rotors to fail unless you invest in one very good one .. $$$$ and we know what that means.
On 6 since 66
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Patzerozero
Senior Member
Username: Patzerozero
Post Number: 4537
Registered: 7-2004
| | Posted on Monday, May 11, 2009 - 9:38 pm: |
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every time i look to the moon....i fall over . will stick with my 4 el long boom 6m yagi . i use a shortened quarter wave vertical antenna for 11m skip. i think you've heard my truck once or twice  ....i don't need no stinkin' beams.
100 watts in & 10x erp = 1kw, 20x erp = 2 kw or 'a half pound', 40x erp = 4 kw & 'another half pound'. the difference between 10x erp & 40x erp is probably a minimum of $2000. if you want it to stay in the air for a while. difference could be double that! on the other hand, stacked m107's could actually yield closer to 60x erp, still not much more then 1 & a half S-units vs the 10x erp of the m105. if you want to be THE big gun on 27.025, 50x erp from an antenna WON'T get 'top dog' spot unless you're doing a couple of kw....100kw erp will get that title....from time to time. clarence carter gets keyed on, prime minista gets keyed on, steel jacket, stonewall jackson, nutcracker, 187, they all get keyed on. |
Bruce
Senior Member
Username: Bruce
Post Number: 5060
Registered: 9-2003
| | Posted on Tuesday, May 12, 2009 - 6:23 am: |
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Pat ...
I thought on the truck you ran stacked beams ....
Yes I have heard you many times the only person I'm able to hear ....
Now as for power the last time 10 meters was open 50% of the people I worked were running 25 watt class radios ....
MANY were S9+
The little 5 watt Yaesus were every where and I worked several of them .... one on batteries ...
Yep ...... when the band is hot it's hot .....
On 6 since 66
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Patzerozero
Senior Member
Username: Patzerozero
Post Number: 4539
Registered: 7-2004
| | Posted on Tuesday, May 12, 2009 - 8:57 pm: |
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i run a 4 watt radio on AM 13, and THE RADIO is ONLY doing 2 watts....really . (most) hams have a bit more respect then many CBers & wait their turn, hence tha ability to get out on less power on 10m. |
Bruce
Senior Member
Username: Bruce
Post Number: 5064
Registered: 9-2003
| | Posted on Tuesday, May 12, 2009 - 9:51 pm: |
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Yep and I have a stack of the new $3 bills .. LOL
Well just maybe we are statring to get some skip ...... would be nice.
On 6 since 66
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Mrclean
Intermediate Member
Username: Mrclean
Post Number: 126
Registered: 12-2003
| | Posted on Friday, May 22, 2009 - 11:56 pm: |
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I have heard most the big guns like the 107 better than the 108 macos. I know a guy a town over that runs Stacked 7s vert and a 7 flat on another tower. The 7s have a little more gain than a smaller beam but where they shine is how tight the pattern is. But you do have to be right on the station you are talking to. If you hear Makers Mark from Indiana thats him. |
Zman
Junior Member
Username: Zman
Post Number: 12
Registered: 4-2009
| | Posted on Sunday, June 14, 2009 - 3:41 pm: |
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I used to use a Moonraker 4 up about 45' and i could talk all over the place both local as well as DX. But all of my DX was on SSB. |
Jim
New member
Username: Jim
Post Number: 3
Registered: 2-2003
| | Posted on Tuesday, June 08, 2010 - 3:42 pm: |
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Hello I have a m-107 that i use on the horizontal plane was very hard to match, swr is about 1.4 on channel 1, 2.1 on channel 23 new rg 217u coax cable, rechecked assembly measurments all seem to be ok, used a difference swr meter same results put antenna on tower up about 55 ft reading didn,t change very much talk mostly on the lower channels because of srw, antenna seem to preform very well i am concern with the bandwith, swr rise very quickly when i go higher on the band. |
Tech833
Moderator
Username: Tech833
Post Number: 1828
Registered: 8-2002
| | Posted on Tuesday, June 08, 2010 - 10:36 pm: |
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Tells you that you have a reactance problem at the feedpoint. You need to get one of the MFJ antenna analyzers or something similar that will read resistance and reactance. That will help you tune it properly.
An SWR meter really isn't enough with a gamma fed yagi. Too many variables. Element length, gamma length, dogbone (shunt) spacing, gamma capacitor value, etc.
Your radio 'Mythbuster' since 1998
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Mrclean
Intermediate Member
Username: Mrclean
Post Number: 137
Registered: 12-2003
| | Posted on Sunday, August 29, 2010 - 8:41 pm: |
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Thats what I like about a 5 element yagi. I tuned for channel 30 with a 259b. I can go down to channel 1 and up above 40 with a swr of 1.5 or less |
