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[TowerTalk] Mosley.. A bill of goods.

To: <towertalk@contesting.com>
Subject: [TowerTalk] Mosley.. A bill of goods.
From: "Jim Thomson" <jim.thom@telus.net>
Date: Thu, 19 Feb 2015 23:38:55 -0800
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Date: Thu, 19 Feb 2015 15:12:29 -0700
From: W0MU Mike Fatchett <w0mu@w0mu.com>
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Mosley discussion

I am glad people keep buying inferior antennas/coax etc.  It makes the 
pileups that much easier to bust..........

Some people refuse to read, learn or educate themselves.

Mike W0MU


###  I find it amusing that Mosleys gain claims are beyond absurd, not even 
close to reality,  
That was as of 5 mins ago..on their site.

##http://www.mosley-electronics.com/pdf/baluns.pdf    Here  mosley explains why 
a balun is NOT
required for ANY yagi, a mosley or any other brand.   More looney tunes. 

##http://www.mosley-electronics.com/pdf/lossytraps.pdf   here mosley explains 
why their 50 yr old 
trap design  has No losses.   And that gain is a function of ele  spacing and 
boom  length..and not 
what constitutes an element. 

## http://www.mosley-electronics.com/pdf/trapdesigns.pdf  Here mosley explains 
their use of 10 ga
aluminum wire wound on a grooved polysytrene form.  ( 10 ga aluminum wire is 
not what I would consider
useful for winding anything.  Grooved polystyrene is bad news..and will 
severely lower the Q of any coil).  

##http://www.mosley-electronics.com/pdf/feedsystems.pdf   here mosley blathers 
on about 52 ohm feed systems
and direct feeding their yagis  with  RG-8..and NO balun.   ( RG-8 hasn’t been 
made since the 70s.  And nobody makes
52 ohm coax since the 70s.)   Mosely is the only outfit that defy the laws of 
physics..and eznec.   Mosley is the only outfit that
can build a multi element yagi....and end up with 50 ohms at the 
feedpoint..with no matching devices.  And no folks, they don’t
employ an OWA design either.   They back their info up with quotes from the 
1952 arrl ant book, depicting how u can feed
a plane jane dipole in the center, with 52 ohms coax..and no balun.   Fact is, 
their trap losses + low Z  yagi  add up to
50 ohms..hence no matching device used.   30 ohm feed + 20 ohms of trap losses 
= 50 ohms.  No hairpin required, direct fed
with ..non existent 52 ohm RG-8.  pretty slick.   And all of this done with no 
computer software designs, and no comparisons done
with other brands of ants. 



## http://www.mosley-electronics.com/pdf/swritis.pdf  Oh this one cracks me 
right up.   here Mosely drones on about 
the unjustified MENTAL attitude of hams.   They continue their diatribe with 
the ... revolting development of swr.
Then in the same breath, they explain how a 5:1  swr is perfectly acceptable. 

##  http://www.mosley-electronics.com/pages/series/monoband.htm    Check out 
these gain claims.... beyond absurd. 
Note how their 6 el 20m yagi has equal spaced eles.   hey mosley, time to buy a 
computer. 

##http://www.mosley-electronics.com/pdf/pricesheet.pdf    $2750 for a  5el  20m 
yagi ?   WTF ?    $1800  for a 4 el
20m yagi, WTF ?    heck a Hy-gain 204BA, new is $500.00   fact is, u can buy 
all new tubing from dx engineering, along 
with superb boom Material, SS clamps etc, and build a better yagi than anything 
out there.   Ok, so u have to drill a few holes
with ur drill press, so what. 

##  f12 still has the best concept for a boom to mast double plate setup, bar 
none.   EZ mount.  Its patented, so nobody else uses it,
but easy to copy for the hb folks at home.   I use 8 x 14 and 8 x 17 al plates, 
.375 thick..+ DX eng super jumbo mast clamps.  Bomb
proof.  I also use it as a mast step. 

http://www.mosley-electronics.com/pages/amateur/multibandhp.htm  check this 
junk out.  lets take the 1st one on the list,
the infamous CL-33-M. http://www.mosley-electronics.com/pdf/amateur/cl33m.pdf   
3 el tribander...on a 18 ft boom. 
Check out the humongous gain figures.   7.3 dbd on 20m  ( same as my F-12  5 el 
20m yagi on a 36 ft boom). 
8.1 dbd on 15M.   ( heck , my f-12 6-el 15m yagi on a 36 ft boom is only 8.5 
dbd). 
8.5 dbd on 10m.....  ( F-12 8 el 10m yagi on a 30 ft boom is only 8.8 dbd). 

http://www.mosley-electronics.com/pages/amateur/ta33jrn.htm   the infamous 
TA-33jr,  3 el trapped yagi on a 12 ft boom.   more gain
than a full size 3 el 20m yagi on a 20 ft boom.   wait it gets better...8 dbd 
on 10m !   And the 33 jr is rated for a whopping 250 w.   now
why is that?    Could it be the  trap losses are so sky high ?   those traps 
are running hot with 250w.   A local ham ran 1200w pep through
his 33 jr..on ssb, and no speech processing.  The traps were beyond melted.  
The polystyrene melts at a low temp amyway.  It looked like
you had ran a propane torch on it.  I Forget what ga al wire they used on the 
puny traps.  Think it was like 16 ga or 14 ga.  

##  My conclusion is mosley is selling amateurs a ..bill of goods.   When a 
Hy-gain 204BA is rated at 6.0 dbd on eznec... and is clearly
10 db louder than a TA-33 jr..... then the 33 jr must have  negative 4 db of 
gain.   Mosleys best trapped yagis only rated for 600w. 
Can u simulate trap losses on eznec ?   If u can cook traps with 600+ watts on 
rtty,  Id say  there is serious losses. 

##  Sure one could build a trap with minimal losses.   .375 inch OD silver 
plated copper tubing  + a fixed ceramic vac cap  would do the trick.
  Air wound of course.   But then the feedpoint Z would be way less than 50 
ohms on 20m... and a hairpin would be required...which of course
wont work on any other band.   Mosley makes a wondeful trapped yagi.  We have 
several here in town, and in the neighbourhood. 
I talk right over them, with just 1200 w pep. Mosley is like water in your gas 
tank.   End of rant. 

Jim  VE7RF




 
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