[Antennas] AG6K Tuner Balun and AEA CIA-HF comments

2003年1月31日 00:14:02 -0600

I have owned and used the CIA-HF since they first came out and have
learned the following:
1. the accuracy of the measurement depends to a large extent on having
a power supply that can provide a minimum of one amp to the unit. Most
of the time the internal batteries will work ONLY if they are freshly
charged. I now always plug in an external NiMH 12-volt battery pack
when I want accurate date. This was confirmed by the factory engineers
when questioned about measurement accuracy.
2. while the readouts are ambiguous about the reactance sign, it is a
trivial matter to resolve this. First note the reported magnitude of
the reactance at the operating frequency. Then reduce the frequency by
5-10% and check the new value of reactance. Then raise it by 5-10% and
check the new value of reactance.
If lowering the frequency increases the reactance, that confirms that
the reactance is capacitive, since capacitive reactance is inversely
proportional to frequency. Similarly, if raising the frequency
increases the reactance, it is inductive.
It takes a few extra steps and some time to make these frequency
checks, but that procedure will provide the proper sign for the
reactive component. Thus, with some manual effort, the CIA can perform
very well as a vector impedance meter.
The AEA CIA-HF is one of the most useful and valued test instrument
that I have - I use it almost daily. And, by the way, it makes an
excellent signal generator. Just set the WIDTH to 0 to stop the
frequency sweep. The frequency is spec'ed at being within 200 Hz of
the dial reading. The useful frequency range extends far below the
spec'ed limits which are based upon waveform distortion limits. This
is also the reason why an adequate power supply is required. Lacking
one, the waveform distorts and the harmonic content introduces all
manner of errors.
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
In the 57th year and it just keeps getting better!
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
K2 #489 IC-765 #2349 IC-756 PRO #2121 IC-756 PRO2 #3235
----- Original Message -----
From: "Sandy and Kees Talen" <[email protected]>
To: <[email protected]>
Sent: Monday, January 27, 2003 6:45 PM
Subject: [Antennas] AG6K Tuner Balun and AEA CIA-HF comments
> The AEA Antenna Analyzer is a really great tool for hams. The
> capabilities and flexibility for measuring complex impedance,
> SWR, line loss, and many input parameters such as setting
> sweep width, center frequency, and graph scaling are surprising.
> It will also graphically display data on it's small LCD screen.
> You can easily overlook some of the shortcomings like having
> to hold the "ON" switch down for 1+ seconds, a somewhat short
> battery life, AND not showing phase angle sign correctly (and
> differently between the data box and the "D" screen). When the
> maximum impedance of 999.9 ohms is reached the reactance
> apparently goes to 304 ohms and the phase angle goes to +/-18
> degrees .... but you are using it outside it's range. The output
> can be further enhanced by getting the "VIA Director" software
> program which offers excellent flexibility for storing and making
> charts for comparison purposes. AND the phase angle sign
> generated is more reliable. I would not get one of these units
> without the software.
>> All in all, this is NOT a Vector Impedance meter but it comes
> close for what I want to do .....and "close" counts in horseshoes,
> hand grenades, and hobbies.
>> 73 Kees K5BCQ
> - - -
>> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
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