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Author Topic: Mosley Mini-33-WARC vs. Cushcraft MA5B - Any opinions from the experienced?  (Read 14281 times)
KD2CJJ
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Posts: 369




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« Reply #45 on: April 14, 2013, 08:42:32 AM »

I know I know... Angry

I will tune it up and see what's next... If it doesn't work out then you will find a mq26 up for sale and it will be a very expensive lesson learned for me. 

I did some measurements today and found that it truly needs to be tuned on 20 as it just starts to dip below 2:1 at 14.330... It's pia without my analyzer now on the mast... Hopefully next weekend I can get the thing tuned.


Again verdict is out still until I can tune the thing...  I suspect though there won't be much improvement...

Stay tuned..



I am not surprised at all. I suggested the CushCraft MA 5B

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73

Mike
KD2CJJ
KA7NIQ
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« Reply #46 on: April 14, 2013, 08:47:41 AM »

There will be some improvement with lower SWR.
How high up is it ?

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KD2CJJ
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Posts: 369




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« Reply #47 on: April 14, 2013, 09:55:53 AM »

About 33 feet...

There will be some improvement with lower SWR.
How high up is it ?


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73

Mike
KD2CJJ
AB4ZT
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Posts: 179




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« Reply #48 on: April 14, 2013, 10:26:05 AM »

I had an MA5B up 35 feet for several years.  It held up well and it had no problem with 600 watts CW.  Beyond that, however, it was a shortened 2-element yagi and performed as such.  Directional, but perhaps only a little better than a dipole at the same height (10, 15, 20).  When I replaced it with a full-size 3-el yagi, the additional element and boom length made a significant difference.  Unless I absolutely had to go with a smaller antenna because of space considerations, I would not go less than 3-el.  Even cost is not an issue - I got my 3-el used for $250.  If I did absolutely have to go with a 2-el, I would probably stick with the Cushcraft.

The specs cited for the 3-el hybrid are garbage.  10 feet is very, very short for a 3-el design.  You are not going to get that gain with a shortened, short boom 3-el yagi.  Although they did specify a dipole at 25-feet as a reference (Huh).  Who does that?   Forward gain should be specified versus free-space references.  My 3-el has 14-foot boom and you really don't want to go shorter than that for 3-el designs.  A step-up is an 18-foot boom design.  When it comes to comparing antennas you pretty much have to ignore claimed specs and rely on what you know about basic antenna design and how each antenna will perform based on number of elements, boom length, element size, etc.

73,

Richard, AB4ZT
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KD2CJJ
Member

Posts: 369




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« Reply #49 on: April 14, 2013, 11:36:28 AM »

Well... for 17m its about 5s points over my end fed (using tuner as it is not resonant on 17m)... Its about 3s directional...  Made a contact into Italy - he was a 5/7 I received a 5/9 plus...  The other bands are dead but I suspect performance will improve as I go higher on the bands with this antenna which is what is proclaims...  

Also depending on which part hover overs my house there is a difference in SWR... at some point I will try to push it a little higher on the mast.... its about 5 feet above the ridge line.. I might be able to push it a little higher..  Wont do that until I can tune 20m... its way off right now...

I will keep the thread updated as I progress with this antenna..
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73

Mike
KD2CJJ
KA7NIQ
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Posts: 267


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« Reply #50 on: April 14, 2013, 02:41:11 PM »

I had an MA5B up 35 feet for several years.  It held up well and it had no problem with 600 watts CW.  Beyond that, however, it was a shortened 2-element yagi and performed as such.  Directional, but perhaps only a little better than a dipole at the same height (10, 15, 20).  When I replaced it with a full-size 3-el yagi, the additional element and boom length made a significant difference.  Unless I absolutely had to go with a smaller antenna because of space considerations, I would not go less than 3-el.  Even cost is not an issue - I got my 3-el used for $250.  If I did absolutely have to go with a 2-el, I would probably stick with the Cushcraft.

The specs cited for the 3-el hybrid are garbage.  10 feet is very, very short for a 3-el design.  You are not going to get that gain with a shortened, short boom 3-el yagi.  Although they did specify a dipole at 25-feet as a reference (Huh).  Who does that?   Forward gain should be specified versus free-space references.  My 3-el has 14-foot boom and you really don't want to go shorter than that for 3-el designs.  A step-up is an 18-foot boom design.  When it comes to comparing antennas you pretty much have to ignore claimed specs and rely on what you know about basic antenna design and how each antenna will perform based on number of elements, boom length, element size, etc.

73,

Richard, AB4ZT
I agree Richard. The Cushcraft MA5B is about the only real small directional antenna I have ever known to work at all.
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N4CR
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Posts: 1702




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« Reply #51 on: April 14, 2013, 02:52:55 PM »

Assuming it's a 50 ohm feed point, the length of your feed line has absolutely nothing to do with where the SWR dips.

Does the SWR dip inside the band and never gets low enough or is the dip outside of the band?
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73 de N4CR, Phil

Never believe an atom. They make up everything.
KD2CJJ
Member

Posts: 369




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« Reply #52 on: April 14, 2013, 04:41:19 PM »

 (I am a relatively new ham so I am still learning) -I noticed that in CW and Digital the direcationality made much more of a significant difference over SSB (using 20m as my reference).  I received probably 1 - 3s difference.  I also noticed with CW and Digital the beam did have a gain of 2 - 3s over my end fed generally.  My last observation is that this antenna is much quieter than my end fed.  Stations that may be 1S lower (in any mode) i can copy better than on my end fed.....  Does this all make any sense?  If so, could you explain any theory behind it?

SWR Stats:

Keep in mind I did absolutely no tuning.  Everything is set as per the manual.   It seems the antenna is fine just needs tuning...

Band = 20M <--- Needs tuning for sure.  I believe tuning will get me to 90 - 100Khz in bandwidth

14.292 = 2.0 SWR

14.325 = 1.33 SWR -- Lowest SWR

14.350 = 1.8 SWR

58Khz in bandwidth


----------------------------------------------




Band = 17m <--- Needs tuning for sure.  I believe tuning will get me to desired bandwidth (maybe even better than specs actually based on where it stands)

18.125 = 2.0 SWR

18.168 = 1.2 SWR  -- Lowest SWR

43Khz in bandwidth

----------------------------------------------


Band = 15m <---- Perfect - within Specs

21.160 = 2.0 SWR

21.275 = 1.1 SWR -- Lowest SWR

21.372 = 2.0 SWR

212Khz in bandwidth


----------------------------------------------



Band = 12m <---- Again needs tuning.  Again believe with tuning I can get this to beat specs.

24.916 = 2.0 SWR

24.990 = 1.2 SWR -- Lowest SWR

74Khz in Bandwidth


----------------------------------------------------------
Band = 10m <---- Perfect within specs

28.102 = 2.0SWR

28.560 - 1.1 -- Lowest SWR

28.986 = 2.0SWR

884Khz in Bandwidth
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73

Mike
KD2CJJ
AF5CC
Member

Posts: 1018




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« Reply #53 on: April 14, 2013, 07:19:49 PM »

I had one of the original Mini Products HQ-1 miniquads that TGM eventually based their design on.  It was the 2 element version for 20, 15, 10 and 6m on a 4.5 foot boom.  As you stated, it performed better on the higher bands than on 20m.  In the 2002 10 meter contest I made 850 QSOs using it and 100 watts from a Yaesu FT100D.  Worked 9M2 for my best catch of the contest (only time I have ever worked 9M2).  On 6 meters I worked Argentina, Portugal, Japan, and lots of Carribean stations with it.

I now have a Cushcraft MA5B I am hoping to get up later this year.  The miniquad replaced a MA5B which I had before.  I got the impression that the miniquad was a little quieter and worked about the same as the MA5B.  The MA5B did seem to have a wider bandwidth, especially on 20m. Good luck getting yours tuned.

73 John AF5CC
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KD2CJJ
Member

Posts: 369




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« Reply #54 on: April 15, 2013, 08:02:50 AM »

Quick question...  (I am a relatively new ham so I am still learning)  When tuning do I start on the outer ring (20m) and work my way in to the inner ring (10m) or visa versa?  I know that one band can affect another when tuning but what is best practice in general when your dealing with a multi-band antenna?

I had one of the original Mini Products HQ-1 miniquads that TGM eventually based their design on.  It was the 2 element version for 20, 15, 10 and 6m on a 4.5 foot boom.  As you stated, it performed better on the higher bands than on 20m.  In the 2002 10 meter contest I made 850 QSOs using it and 100 watts from a Yaesu FT100D.  Worked 9M2 for my best catch of the contest (only time I have ever worked 9M2).  On 6 meters I worked Argentina, Portugal, Japan, and lots of Carribean stations with it.

I now have a Cushcraft MA5B I am hoping to get up later this year.  The miniquad replaced a MA5B which I had before.  I got the impression that the miniquad was a little quieter and worked about the same as the MA5B.  The MA5B did seem to have a wider bandwidth, especially on 20m. Good luck getting yours tuned.

73 John AF5CC
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73

Mike
KD2CJJ
KB6HRT
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Posts: 125




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« Reply #55 on: April 15, 2013, 10:17:06 AM »

Mike,
 The key for good reading SWR with the MQ-26 is using a feeder line of 100' of RG213U for broadness of useable SWR
your transceiver see's for 20m with antenna. Here are my readings with 50 watts AM applied at the shacks coax end.  SWR at 14.225 1.5  SWR at 14.275 1.4 SWR  14.300 1.3 SWR  14.310 1.6 SWR
 14.320 1.8 SWR  14.330 2.3 SWR 14.340 2.6 SWR and 14.350  3.1 SWR  You can see SWR readings are within limits of the tuner in most transceivers with a built in tuner in of 3 to 1 or less. After tuned SWR is 1.1 from 14.225 - 14350.  As you can see have my MQ26 dip at 14.300 which works great for my 20m needs. My antenna uses the proscribed balun, an is installed at 36' to the bottom an the antenna can see unobstructed 360 deg..............73s.........kb6hrt
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KA7NIQ
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Posts: 267


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« Reply #56 on: April 15, 2013, 10:41:19 AM »

Mike,
 The key for good reading SWR with the MQ-26 is using a feeder line of 100' of RG213U for broadness of useable SWR
your transceiver see's for 20m with antenna. Here are my readings with 50 watts AM applied at the shacks coax end.  SWR at 14.225 1.5  SWR at 14.275 1.4 SWR  14.300 1.3 SWR  14.310 1.6 SWR
 14.320 1.8 SWR  14.330 2.3 SWR 14.340 2.6 SWR and 14.350  3.1 SWR  You can see SWR readings are within limits of the tuner in most transceivers with a built in tuner in of 3 to 1 or less. After tuned SWR is 1.1 from 14.225 - 14350.  As you can see have my MQ26 dip at 14.300 which works great for my 20m needs. My antenna uses the proscribed balun, an is installed at 36' to the bottom an the antenna can see unobstructed 360 deg..............73s.........kb6hrt
Heck, why stop at only 100 feet of coax ? Why not 2 or 3 hundred feet, and really introduce some loss, for best SWR ?
Any antenna that "requires" a long length of Coax for best SWR IMHO, is a flawed antenna.
To depend on feed line loss to achieve low SWR or Wide Bandwidth is not the best plan.

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KD2CJJ
Member

Posts: 369




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« Reply #57 on: April 15, 2013, 01:15:52 PM »

KA7NIQ - I agree, I wouldn't want an antenna that needed a specific feedline length; though I tested it anyway and it didnt help any by adding 50 feet... SWRs didnt budge...

I then proceeded with the SWR sweep accross all supported bands, which I would have done  easily with an analyzer but I used my Bird meter to calculate the SWRs.

KB6HRT - As you can see the antenna is fine based on the SWR sweep... It IS resonant (assumed based on a 1.5 or lower swr) at some part of the corresponding band.  From my analysis, I just need to tune the antenna.   I am running LMR 400 Flex... I am also using the prescribed balun as per the instructions.

I will report back when I tune the antenna but from what I can see tuning will just shift the resonant point - in other words performance will not improve much... 

PS - the more I use the antenna the more I am happy with it -- It is some times is weaker than my end fed, some times its 1 or 2s points stronger enough for me to copy the station where on the end fed would be very difficult... For 17m - 10m it completely destroys my end fed - at least 5 - 6s difference in favor of the Mini Beam.
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73

Mike
KD2CJJ
KA7NIQ
Member

Posts: 267


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« Reply #58 on: April 15, 2013, 03:32:50 PM »

KA7NIQ - I agree, I wouldn't want an antenna that needed a specific feedline length; though I tested it anyway and it didnt help any by adding 50 feet... SWRs didnt budge...

I then proceeded with the SWR sweep accross all supported bands, which I would have done  easily with an analyzer but I used my Bird meter to calculate the SWRs.

KB6HRT - As you can see the antenna is fine based on the SWR sweep... It IS resonant (assumed based on a 1.5 or lower swr) at some part of the corresponding band.  From my analysis, I just need to tune the antenna.   I am running LMR 400 Flex... I am also using the prescribed balun as per the instructions.

I will report back when I tune the antenna but from what I can see tuning will just shift the resonant point - in other words performance will not improve much... 

PS - the more I use the antenna the more I am happy with it -- It is some times is weaker than my end fed, some times its 1 or 2s points stronger enough for me to copy the station where on the end fed would be very difficult... For 17m - 10m it completely destroys my end fed - at least 5 - 6s difference in favor of the Mini Beam.
Comparing it to your End Fed is not what you think! If your End Fed is an 80 meter end fed, or even a 40 meter End Fed Wire, it will have lobes, some with a little gain over a dipole, but it will also have Nulls (holes in the pattern) that can be 20 db deep!
LOL, a Dummy Load mounted at 33 feet can sometimes "outperform" a long end fed wire, especially if that dummy load causes the coax to radiate.

A true comparison for your antenna is to compare it to a 1/2 wave dipole, mounted at, or close to, the same height.

I can assure you, that if and when you compare that antenna to a 1/2 wave dipole, you will never see " 5 to 6 S Units difference"  Wink

By the way, welcome to the hobby, since you are a New Ham!

I can not tell you how Many "antenna projects" I have had, that did not turn out like I wanted them to.

Those god darn laws of physics kept ruining my plans.

However, I learned a little, from each and every failure, and I am still learning!





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KD2CJJ
Member

Posts: 369




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« Reply #59 on: April 16, 2013, 06:59:13 AM »

The more I use the antenna the more I getting acquainted the more I like it, the more I see my install is contributing to some of the negatives.


I have found that my SWRs change considerably pointing north and south (where half of the dipole is over my house and half is over free space).  When its east / west either the radiator or driven element is over free space or over the house - the SWR drop about 1/2 of its reading or more (example it can go from 1.2 SWR to 2.0.  That explains why I was seeing some odd performance characteristics and SWR curves when the beam is pointed north and south!..... For example stations in Florida (My QTH is Long Island) if I rotate the beam SE the stations dB actually increases, when reason would say that having the beam pointed directly at the station should yield higher dB - but that is not the case for stations north and south of me.  This morning it was just about 1 - 2S difference just by slightly turning the beam off center of the station!   -- all this  I suspect due to it being too close to the house, detuning the antenna.   

I can get the antenna about 2 feet higher on the current mast before I will need another mast - I will attempt that this weekend and report back. 



Lessons learned this antenna seems to be very sensitive to housing structures - My roof is tar shingles, wood structure, vinyl siding and have aluminum gutters (though they are a fair distance, like 10 feet to the antenna - could they be having an effect??  Also I have a Power cord in my attic up at the peak with bulbs attached running the entire length, could that be having an effect?).



Comparing it to your End Fed is not what you think! If your End Fed is an 80 meter end fed, or even a 40 meter End Fed Wire, it will have lobes, some with a little gain over a dipole, but it will also have Nulls (holes in the pattern) that can be 20 db deep!
LOL, a Dummy Load mounted at 33 feet can sometimes "outperform" a long end fed wire, especially if that dummy load causes the coax to radiate.

A true comparison for your antenna is to compare it to a 1/2 wave dipole, mounted at, or close to, the same height.

I can assure you, that if and when you compare that antenna to a 1/2 wave dipole, you will never see " 5 to 6 S Units difference"  Wink

By the way, welcome to the hobby, since you are a New Ham!

I can not tell you how Many "antenna projects" I have had, that did not turn out like I wanted them to.

Those god darn laws of physics kept ruining my plans.

However, I learned a little, from each and every failure, and I am still learning!






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73

Mike
KD2CJJ
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