I built an original N2PK, that interfaced via a parallel port. I did a minor
upgrade that changed to an improved DAC. I still have a Win XP laptop with a
parallel port so can still use it. Later it was refined to USB but I never
upgraded, although I still have the unpopulated circuit boards for the later
configuration.
The reason for not finishing the project, other than time, is the fact that I
bought the other ANA under discussion, the VNWA-3.
As someone who started using a grease pencil on the CRT for "calibration" of a
waveguide reflectometer, graduated to an HP8410 then an HP8510, I never cease to
be amazed that I can hold something with similar accuracy (albeit less frequency
range) in the palm of my hand.
Wes
On 8/20/2016 11:37 PM, Bob Albert via time-nuts wrote:
Well that's a start. Thanks for the link! I would need more information, as
this project goes into areas that are new to me. And there is no clue as to
the cost of construction.
But I'll study what's there and if nothing else, learn something.
Bob
On Saturday, August 20, 2016 10:46 PM, Orin Eman <[email protected]>
wrote:
To 60MHz: http://n2pk.com; PCBs available here: http://www.makarov.ca/vna.htm
To 500MHz, lower dynamic range to 1.3GHz:
http://sdr-kits.net/VNWA3_Description.html
OK, so the latter isn't build it yourself anymore.
I have version 2.6 of the latter and it works really well to about 575MHz.
Traces can get noisy after about 575MHz.
Remember these VNAs are only as good as the calibration kit you use with them!
Orin.
On Sat, Aug 20, 2016 at 9:46 PM, Bob Albert via time-nuts <[email protected]>
wrote:
I was interested in this, but my needs are mostly below 100 MHz. I wonder what
could be done similarly for this lower range...
Bob
On Saturday, August 20, 2016 8:54 PM, Richard (Rick) Karlquist
<[email protected]> wrote:
Another great posting, Attila.
When I was with Agilent, we looked at all kinds of
simplified network analyzer architectures, and I
would have to say the author is really well informed.
One issue he doesn't seem to be aware of is that the
ADL5801, when driven single ended, has some quirks
below 100 MHz that I discovered experimentally.
(The data sheet is silent on this). IMHO, it
would be worth 7 Euro's to use a balun, however,
I would like to know the part number of this
supposed component. I am not so sure about MCL
actually covering 30 MHz to 6 GHz in the same
balun. Sometimes their advertising is confusing,
and when they say .03-6 GHz baluns, they mean
that the range can be covered in several bands
by several model numbers.
Still, quite impressive work by an individual
practitioner.
Rick
On 8/20/2016 7:19 PM, Attila Kinali wrote:
Moin,
I stumbled over a new open hardware/source VNA design:
http://hforsten.com/cheap- homemade-30-mhz-6-ghz-vector- network-analyzer.html
Unlike other designs out there, this one is very well done and has very
little room for improvement, without increasing the price considerably.
About the only things i would do different is to use two receiver
channels, one fix connected at the TX source to be able to do a
difference measurement between TX and the RX channels and thus
improving precision. And the other would be to use a dual ADC
with an FPGA for the data processing, again in order to increase
performance.
But as I wrote, both changes would increase complexity and price.
Other than being a well thought through design, the website also
explains all the big design choices and why this or that has been
done instead of one of the many alternatives. That alone makes it
worth reading, IMHO.
Attila Kinali
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
