Hi;
Thanks to all who responded to my first query. Extremely interesting.
Due to large number of the responses I'm writing to the reflector.
I used to have the MFJ259B and was very happy with it until I realized I
need more than just the SWR - in fact I'd like to know both Z and +/- X.
So I sold it. By reviewing Autek "rigs" it was the VA-1 that caught my
attention. Then I went on to see the AEA products. I've downloaded
their manuals - VIA and CIA - and one thing what I didn't like about the
AEA was that they keep the owners of CIA in the dark. For the VIA they
have, so called, commercial manual which I, personally, would call just
a manual, covering what should be covered including accuracy etc. The
manual for the CIA is just like an advertising leaflet treating owners
of this cheaper version like kids. But what I noticed in the performance
spec for the VIA is accuracy dependence on magnitude of X or ratio of
X/R. For the SWR >=2 the value of X can be almost +/- 40% . The sales
guy at AEA told me that the VIA and CIA are practically the same so this
, I understand, applies to the CIA as well. But that's fine - that's
what the "rig" can do. Now: how is it with the VA-1 ?. I haven't called
them yet hoping, that I can find someone who has investigated this and
has the answer. Has anyone who owns the VA1 tried to connect a known
resistance and capacitance in series - different combinations - at the
end of a length of a coax and compared the measured values with the real
ones ? . Yet another thing is measurements dependence on QRG. This kind
of a test would be very informative ( if it is repeatable) - perhaps one
could make up a correction factor table of some sort.
Some of you reported on poor design/make quality of the Autek sets. If
the manufacturing methods and chosen mechanical design + errors were
taken into account when setting for a specific performance then,
perhaps,the units are almost undestructible like the Heathkits or etc...
- I don't know - just a speculation.
If anyone has any accuracy data for the VA-1 - I'd appreciate some info.
Thanks again for the great response - with your permission (please let
me know) in a couple of days I will compile some of the responses
omitting the call signs to protect your privacy and post it on the
reflector for "pro publico bono" - for others to benefit from this
query.
tnx, 73 Art VE3PND
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