[Amps] Dummy load varying R

[Roger (sub1)]

On 6/10/2011 3:10 AM, Ian White GM3SEK wrote:
> Roger (sub1) wrote:
>>> That is making the assumption stretch that the measuring instrument is
>>> correct. As I said earlier the 259 has problems with the digital display
>>> readout section and we havent heard back yet what the analog VSWR meter on
>>> it reads.
>> Last I knew and it has been long time, accurate, calibrated instruments
>> were expensive. Course it was cheaper to get them calibrated than to
>> purchase the equipment to do the calibration and then sent it in for
>> calibration.
>>
>> I do hear tell there are some pretty good ones becoming available at
>> reasonable prices, although they are a tad more than what MFJ sells.
>>
> This is about much more than a higher price point. It's about a new
> generation of amateur-priced vector impedance meters that are in a
> totally different league from the traditional MFJs and Auteks.
>
> The key feature is the built-in error compensation. Before making a
> measurement, the instrument "requests and requires" that you step
> through a calibration procedure which involves connecting first an
> open-circuit, then a short-circuit and finally a 50R reference load. The
> instrument computes its own internal errors - and then removes them from
> your measurement results.
>
> With these new-generation Vector Network Analysers, you are now playing
> alongside the professionals. The accuracy of your measurement is no
> longer limited by the instrument but by your own care, skill and
> understanding as a user. That is a challenge... but it's also an
> education.
>

Thanks, Ian,

Es

73

Roger (K8RI)
>