[Towertalk] SteppIR at Field Day comments

mwdink@eskimo.com mwdink@eskimo.com
Tue, 25 Jun 2002 13:25:56 -0700


K7LED Field Day operations, Western Washington, CW station 
This is all very unscientific but there have been a lot of 
requests on Towertalk for anecdotal commnets about this antenna.
Here is just my two cents. I didn't put it together - just a
user, observer, and possible future purchaser.

73, dink, n7wa

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Had opportunity to use a new 3 el SteppIR antenna at our Field Day 
operations this year. Went up 35' on a temporary tower (easily
trammed). Don't know that I would want to take it off the home
tower every year for FD but this was brand new so we went for 
it at K7LED. It certainly comes in a fairly compact package 
when completely broken down. I think there is good DXpedition 
possibility here though I think it's twice as heavy as the C3S
because of the element housings. 

Due to conditions, it really only got a work out on 20M. Felt loud 
(I know - very subjective and this was mainly a USA event) with 
it all weekend. Certainly, it was doing better than our normal 
antenna - a C3S. (Which is expected as the C3S is only 2 elements
on each band.) Before the test, played with the 180 degree reversal
feature. It was neat to sit there on a loud signal, hit the button 
and watch S meter drop to zero. Hit it again, and back up she came. 
However, being almost as far NW as you can get on mainland for our 
FD site, front/back isn't a big issue <g>. 

Band changes were easy. - hit the band button, wait for the flashing
asterisk to go away on the display and it's ready. You can adjust 
the specific frequency up or down in 25-50 KHz steps as well. (That
may be programmable along with the specific set point - I didn't check.) 
Could be connected to a radio and then the button pushing is 
eliminated as well but we didn't have that connection for Field Day.
SWR was always less than 1.5 to 1 once the elements had set. 
Control box was easy to use. Device come with a small 2Amp
switching supply. We ran it through 150 feet of supplied small 
gauge cable - no issues running the stepper motors. I don't know 
what maximum run is possible with that power supply and cable
size. 

I can't find any performance issues at first bite. I'm really
looking forward to playing with it at home (it's borrowed fron N7BV)
with the idea of buying one myself and using it as the lower antenna
in a stack. The idea of only needing to rotate 180 degrees is 
really appealing. 

While I didn't assemble this unit, the guys who did made a couple
boo-boos out on site. The guys at FluidMotion were very nice, helpful,
and courteous while helping us fix our errors. Extremely quality
conscience at this time. There was one manufacturing error (loose
cable nut I guess you would call it) we noticed on one of the 
stepper housing units which didn't affect our operation but they 
wanted it back to look at it. (Granted, the manufacturer is local
so that was easy for us.) It took two guys (totally unfamilar 
with the antenna) about 2 hours to put it together - including 
undoing the boo-boo's.

All in all, I was impressed. What would I change? For improvements, 
I think purchasing miltary type 16 pin connectors and breaking the 
hard-wired connection between to the antenna and the control box
would be a good idea. (They do have an enclosed connector block 
system but I would rather use a plug when up on the tower.) There is
a standard SO-239 for the coax connection on the driven element
housing so that disconnects easily. 

I think the mast to mounting plate u-bolts needed upgrading as well. They 
seemed like normal muffler clamps and a bit tight for the 2 inch 
aluminum mast we were using (They dug into the mast material and 
I had to bang the saddle off when we tore down.) Couldn't slide 
the antenna up or down the mast with them on either. There didn't 
seem to be any issue with the clamps that went from the boom to 
the mounting plate.

Only time will tell on weathering but the elements
seemed well made and very strong. They telescope down
to 4' tubes like a BIG collapsable fishing pole. (each element
end has a bit of foam to keep out bugs. I don't think they
will hold moisture but I can't say that for sure.) The
elements run inside the tubing. There is a friction fit for
each section of the element tubing and special special tape 
to keep them from collapsing in the permanent installation. 
We just used electrical tape for the weekend. There was no 
sign of loosening during the 36 hours or so it was up and 
we get some good winds on our beach site. The boom is four 
sections of thick aluminum tubing machined to fit 
togther. The housing for the elements and motors seemed sturdy and well 
put together (excepting the cable nut mentioned previously).  
Being unfamiliar with the device, one problem was trying to 
remember which end was the front while putting it on the tower. 
We finally marked it with electrical tape but once you owned it 
for a while you would know the driven motor housing belonged in 
front of the mast (or was it behind? <g>). 

Again, this was just first impressions but I'm looking forward
to the next couple of months (and longer if I can twist N7BV's
arm). 

73
dink