Good day all.
I have continued to located and read through whatever online documents I have been able to find on this project.
As well I have spent some time in the workshop taking stock of what I have on hand and how I can make use of same.
I do not have a Bondar GPSDO and it is unlikely that I will purchase one. However, I do have something which is called RFZero (
https://rfzero.net/ ) which unfortunately like many things these days is suffering from the global shortage of parts and is currently unavailable. The RFZero is functionally similar to the Bondar GPSDO and among it's available applications programs is one to use it as a GPSDO. Mine is now set up for this function and providing programmable reference frequencies as desired.
Although I have the parts on hand to build the GRAPE V1.x receiver ( except for PCB ) I will not be going that route. I do have several other options however.
First option is to use a custom version of the JUMA RX-1 direct conversion receiver (
http://www.jumaradio.com/juma-rx1/index-en.html ). I have one connected to my RFZero GPSDO sitting on my desk and have test monitoring WWV on 10 and 15 MHz plus CHU on 7850 KHz.
I am in a unique location with respect to CHU. I live 20 nautical miles almost due East of the CHU transmitters and receive CHU on 7850 KHz continuously via ground wave plus using a low mounted dipole I also receive CHU on 7850 KHz via NVIS.
I still have not taken any time to sort through the Raspbery PI GRAPE image and software but I have found and restarted my old Spectrum Lab configuration files and have running that collecting images. Several hours for WWV on 10MHz and currently for CHU 7850KHz. Images are uploaded to dropbox every 30 minutes and each image is approximately 75 minutes duration with a vertical frequency scale of approximately +/- 3.5 Hz. Next step will be configure Spectrum Lab to create txt files containing the FFT and various other calculations and once I better understand the GRAPE file format requirement I will see if I can match that with Spectrum lab.
this is the like to my Dropbox images:
File names should be self descriptive.
Comments, pointers, and suggestions are welcome.
cheers, Graham ve3gtc