Here's another nice new toy from DL-land by way of the UK. The designer
is DG5MK.
https://www.sdr-kits.net/VA5_Page
$235 got the analyzer and a better quality cal kit shipped to my door
just before CQWWCW. The better Cal kit was $20 of that cost. It took
less than two hours to put it together (as I get older I get slower).
It's a single-port true vector analyzer, and runs either stand alone on
two internal AAs or from VNWA software via a USB port. Decent build
quality, BNC is soldered to the board and bonded to the case at the
point of entry. The case is a 2-piece metal clamshell, screwed together
at four places. In other words, it's well shielded and has no Pin One
Problem!
There's a beautifully printed manual that covers building and operation,
with excellent color photos. Text is excellent in the building section,
pretty good in the button-pushing area, a bit weak in the concepts area,
and badly disjointed to point of being awful in its description of
calibration. The latter is a big deal, because it's the first thing you
do once you turn it on!
As near as I can tell,when running from VNWA software (FREEWARE), it can
do almost everything the VNWA can do with S11 (single-port)
measurements, except that choices of sweep rates and dwell time at each
data point are a lot more limited. That means I can use the excellent
TDR function built into the VNWA software! I don't know yet if I can
import complex data made stand-alone. BTW -- the measurement plane is at
the end of a 5 ft piece of RG142 from my stash. I find that a convenient
length for getting to where I can measure antennas from my shack.
This box is designed to be the one you use in the field and at the top
of the tower, but with the VNWA software, you can make measurements in
the shack, including TDR, then export antenna data to SimSmith to
transform it to the antenna ffeedpoint, then use SimSmith to design
matching networks and compute loss in the feedline and matching networks!
This is a VERY nice unit, and a real bargain!
73, Jim K9YC
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|