I think everyone knows that the Mosley gain figures on some of their
antennas are incorrect. But let's go back many years when all antenna
manufacturers were inflating their gain numbers. Back then we didn't know
about gain as we do today and we all relied on those numbers in choosing an
antenna. Just look back at some of those antenna ads with ridiculous
numbers. In order to stay competitive, all had to play the 'gain game'.
Yes Mosley needs to correct their gain numbers.
I don't really care what manufactures say in their brochures. Part of it is
salesmanship. What is important is hands on experience. Quality of
workmanship, ease of assembly, ease of installation, durability, some gain,
customer service, cost, delivery and so on.
Regarding your friends TA33 Jr. I have a different first hand experience.
My first and only installed Mosley beam many years ago was a TA33 Jr. I ran
over the rated 500w, 1200pep trap rating using a SB-220 and never harmed the
traps. That TA33 Jr replaced a triband Gem Quad that was a bitch to tune
back then. The TA33 Jr was so much easier to tune, and install than the
Quad.
I would be interested in seeing a comparison between the TA33 and A3 trap
short boom antennas on all three bands. We should know that these antennas
will not perform as well as a 204BA on 20m. IMO they are not that bad on
10/15m. A lot of improvements have taken place since some of these antennas
appeared in the market years ago.
Doug
I wasn't born in Saskatchewan, but I got here as soon as I could.
-----Original Message-----
##### Nobody ever busted through a pileup.... cuz they had 40 db FB + 60db
FS.
Its ERP on TX....and nothing else. Where the extra .5db or 1-3db of ant
gain helps
is in busting a pile up. If the DX station hears 100 guys calling him..and
they are all exactly
S9.... and the 101st fellow comes along and is S9 +2db... guess who gets
through.
## Of course, ERP on TX is the sum total of everything from feedline loss,
TX power measured
at the feedpoint, ant gain, and how high the ant is, take off angle, etc,
etc.
## How u achieve your ERP on TX is up to you. You can only do so much.
But when u start losing
a few db from your trapped mosely, that stings. If a 3 el 20m monoband
yagi is say 5.3 dbd,
and your CL-33 is 2-3db down from that... that's a huge amount. That's over
half the gain of the
monobander right there ! Ditto with feedline loss. Say u had 2 db of
feedline loss to ur mosley.
Now u have lost a total of 4-5 db. If all u have is a SB-200, you just
lost another 3 db.
## If anybody thinks there is minimal difference between a TA-33jr and a
hygain 204BA, try the test
yourself. Put up 2 x 50 ft towers, 200 ft apart, side by side..and equal
length feedlines. Both ants
pointed at EU... then compare. Forget the test range, the only range that
counts is the one between
your back yard and downtown EU..or anywhere else. The difference will
make u gag. The 33jr works on 15+10M...
and the 204BA doesn't. The tribander has a huge advantage with extra
band coverage.... which
is its only advantage.
Jim VE7RF
### 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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