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Author Topic: My Antennas  (Read 4462 times)
W2BLC
Member

Posts: 40




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« on: April 10, 2018, 05:06:21 PM »

Got a question? Just email and you get a fast answer. That said, his products work as stated, so you will probably never need to call.

Bill W2BLC
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K6BRN
Member

Posts: 1346




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« Reply #1 on: April 21, 2018, 08:39:38 PM »

I second the motion and vote for MyAntennas.  I have quite a few of their products - at least 5 wire antennas and 3 or 4 RF chokes.  And Danny has always been very responsive.

Brian - K6BRN
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KF7YRS
Member

Posts: 2




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« Reply #2 on: May 01, 2018, 05:25:24 PM »

I like them too, great product (8010-1K) which I have recommended and others have liked.   I have had no problems, so I have not needed to call customer service.  This is my "go to" antenna for all HF bands.  I am a very happy customer.
73
Lee
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KA4DPO
Member

Posts: 1320




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« Reply #3 on: May 26, 2018, 07:16:00 AM »

Not sure how they tame a voltage feed point.  Ordinarily, a half wave antenna is cranky, especially around other objects like buildings and trees.   A J-pole is a half wave antenna and uses a quarter wave transformer to obtain a match.  The matching section must be tuned in order to obtain a proper match depending on the antennas location and proximity to other stuff.

So I not only don't see any way to tune this thing, I don't have any idea how you would obtain a match on more than one band?  I suppose a 25 or 30 to 1 transformer might be used although I have never seen one.  My experience with end fed antennas is that the RF voltage can be extremely high and so can the impedance, on the order of 1500 to 5000 ohms depending on several factors.  It would be interesting to put one up on an antenna range and see what the field strength is compared to a resonant half wave dipole on each claimed band.

According to the manufacturers web site, the matching transformer enclosure needs air vents to maintain temperature and pressure.  That means it gets hot, and heat means loss, and loss is how it make it look like a match.  Sounds to me that most of the power is being absorbed by the transformer instead of radiating.  I suppose if you have never had a really decent antenna you wouldn't know the difference.

So based on fact, I remain very skeptical.
« Last Edit: May 26, 2018, 07:24:52 AM by KA4DPO » Logged
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