Monday, June 14, 2010

Antenna analyzer from China

An antenna analyzer is a very useful piece of equipment and I have never regretted buying my AA-200, though I probably wouldn't get one now with the current model priced at £410.00. Even the basic MFJ-259B which is not exactly renowned for its quality construction will set you back £260.00. So I was interested to discover that the Chinese have entered the market with the Feature Tech AW07A which can be bought on eBay for a much more reasonable £160.00.

The unit can measure RF impedance and SWR from 1.8 to 490MHz (making it more directly comparable to the MFJ-269B model) as well as measuring capacitance and inductance. It may be used as a non-precision signal source and frequency counter, and with the addition of an inductor may be used as a dip meter. It looks like a nice addition to any amateur's toolkit.

8 comments:

S.o.a.I said...

I built one of these over the past winter: http://www.users.on.net/~endsodds/analsr.htm

Not all the bells and whistles as some of the other units. But it was a fun build and gets the job done. Price was good, I paid $150US shipped from VK-land (http://www.scarc.org.au/kits.html) Would highly recommend it.

Also if it breaks you have a chance at fixing it because you built it. And if you do get one there's a great set of build videos, first one in the series is here: http://www.youtube.com/watch?v=IpUe-0cqFvI

73
Jay aka KD8EUR

Theodore said...

Interesting bit of gear Julian.
May be an inexpensive option, but from the specs it is basically an HF/6m unit for impedance, and swr on VHF/UHF.
The issue with this unit is that you never know how accurate they are, and calibration may be a byzantine puzzle.
Also, as we have all experienced, manuals may be less than intelligible.
The general case with all these types of units is that they consist of an oscillator, a bridge with a DAC and microprocessor to crunch the numbers.
The accuracy depends primarily on the bridge components, since garbage in - garbage out.
This is why I would be very interested in the calibration procedure, since an instrument which gives false readings is worse than none.
All the other features such as C,L,Z etc are nothing more than simple mathematical manipulations of this bridge data, which can be computed easily from just R and X.
There is a kit designed by VK5JST which if you are into kit making, is inexpensive and produces good results with simple calibration.
It only covers HF though.
Having been caught in the past with buying "cheap" only to have to pay much more in the end to get something decent, I am a bit wary of these products.
However, there is no reason in theory why a Chinese produced and designed unit would not be capable of good results, but I think I will let someone else be the early adoptor.

g4ilo said...

I guess the kit you mention Theo is the one Jay built. I'd have built one of those too had I known about it. I suggested a couple of times in the past to Elecraft that an analyzer would make a nice addition to their kit range.

Olaf said...

The MiniVNA covering up to 180 MHz is a nice unit which readily displays all data such as R, X, SWR etc. The unit can also be used to check filter curves, cable attenuation etc as there is both an input and an output port.

Very versatile and easy to use.

73 de Olaf

VK6GA said...

Hi all,

Long time reader of this blog but haven't commented at all. Julian I've been using your VOAprop program for a few years now and find it very helpful, thanks.

The VK5JST 1-500Mhz Aerial Analyser is a very simple kit where you use a low powered tx (I use a VX-7R or 706MIIG) to check SWR. I've built two of these myself and work very well when compared to a normal SWR meter. It cost about $60-70 Aus to built with new components.

check the web page: http://www.users.on.net/~endsodds/vhfuhfan.htm

Scroll to the bottom and you can download the article that was published in the WIA AR mag.

As for the AW07A SWR HF/VHF/UHF Analyzer, there is a on line shop here in Oz that are trying to sell it for $299.

Cheers,
Adam

Antonio Martínez said...

Hi, a spain antenna analyzer in kit, with usb connect for PC. Description.
http://www.ea4frb.eu/sark100.html

BD5QDM said...

Hi all,
Thanks very much for paying attention to AW07A. The new manual for the this cost-effective analyzer has been updated, please download from www.hamradioinfinity.com, thanks!

spykillah said...

some info: Feature Tech AW07A is not available anymore.. :-)

its now MFJ 266.. price is about 350 $

73,
Ron