The new software is available at http://authorityfile.co.uk/NBSC/Home/OtherStuff
Here's a few pictures of it being used in anger to map the properties of the 10.7MHz input filter of my log-detector (an SA614 RSSI output with 2x 10.7MHz cermic filters).
They're interesting in that they show the harmonics generated by the DDS-60 daughterboard. These appear to be much better than the claimed 40dB down at about 55dB down - though this is just those that fall in the 10.7MHz region.
The traces are all with 10dB per division.
0-60MHz
0-20MHz
10-12MHz
The slight sparkling on the pictures is due to the fact that the scan doesn't progress linearly but is a set of stepped frequencies. This isn't a problem but shows up noticably on a photo. However, a slower scan rate gives less "sparkly" pictures but I had to run these at 50Hz otherwise my shaky hands made the pictures blurred!
Dom
Hi Dominic, thank you so much for sharing this nice project with us.
ReplyDeleteI followed it all the way and learnt a lot from it.
One thing I could suggest is the use of RF2420 as a programmable attenuator. Very cheap and efficient.
Thanks again and good luck!
Simon
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