I made a PTT circuit on a tiny veroboard so that the CN-0417 only gets 5V on transmit because it getting so hot, and also PTT for the PA. Its working very fine with a little delay about 1/4 to 1/2 sek – thats fine for SSB. I strugled a little with the F5OEO firmware to get the PTT working on GPO0 output on the Pluto, but after trying several times in upload of firmware from F5UII I stopped, because there is not coming any signal out on Pluto GP0 when keying PTT. I contacted DG9BFC Siegfried, that had written on the net about F5OEO and he told me that SDR Console only activates PTT when the drive is higher than zero – now it works fine. Circuit description / layout comes later.
Next I could’nt stand to try transmitting, to see how the poty is function and how the transmitter works with antenna. After testing that something is coming out and I can hear myself on the QO-100, I managed to get my tramsmit signal to be near my receive frequency. Suddenly there where a station on the frequency and my microphone was attached. It was DC3ZB Per, that lives near Frankfurt in Germany, that could give me a rapport on my signal. At first there was a minor problem with the sound of my voice and after about half and hour I was drifted about 1 Khz because of my not stabilized krystal osc. on Pluto board. But I found out that the PA works at 60% – about 5 Watt, and is not getting hot at all with 24V – thats fine. Yesterday I managed to move the satdish to its final destination, and getting the transceiver box mounted behind it. Look at the new pictures. To get rid of the frequenz drift when transmitting, I managed to install a Leo Bodnar mini GPSDO in the box. I also desided that the power of 12 V and 24 Volt, are located external. Antenna for the GPSDO is placed inside the box – there is no problem in receiving sat GPS signals inside the plastic box. 5V Power for the GPS unit, is delivered from a new PTT board I made because the first version was to high inside the box. The new PTT board will be made as a PCB that can be copied later.
My transceiver has now worked for about 2 month without problems, but after I finished building the remote power circuit and have mounted it in the garten house (look under other projects), there was a problem in connecting the ADALM Pluto – no respond. I though that I had made a failure in the connections, but all things where functioning well – so there must be a problem with the Pluto. I took the hole case inside to measure what was wrong, and found that it had changed the IP address back to default in the 192.168.x.x segment. Got it connected with Putty again and after many hours of changing the config.txt file and change startup settings with putty, I came to the following result:
After connecting Pluto to a PC with USB cable, It will be on a USB port that can be found under Ports in the device manager. Start Putty program and connect it to the Pluto on that port with serial connection type. A new window will come with credentials for login: root and password: analog – that will give a root login: #
The following commands must now be entered:
#fw_printenv // That will give a complete status of all settings
2 things are important when using external clock to the Pluto: refclk and source that can be found with:
#fw_printenv | grep ad936x_ext_refclk // Display setting for refclk
#fw_printenv | grep refclk_source // Display settings for source to clock
For me the clock frequenz must be 40 Mhz as the default clock on the board, but now external from GPSDO.
#fw_setenv ad936x_ext_refclk 40000000 // That will change the clock configuration to 40 Mhz (value in hz)
#fw_setenv refclk_source external // Change to external reference clock
I still had problems with the settings that after a power cycle was reset to defaults again, but here is the solution:
#fw_setenv qspiboot_extraenv true // This will preserve the settings still after a power off
To the last all settings have to be saved when entering new data with this command:
#pluto_reboot reset // That will apply changes and reboot the Pluto
SDR Console settings for frequenz definitions are – RX: 9749.982.000 TX: 8089.500.000
I hope that this will keep my setup in the Pluto for a while 🙂 – until now it works perfect.
Next thing is to dig a cabelduct from my garten house to the satdish.
Update: I have changed the Little Oscillator on the Pluto PCB for better frequenz stability to 0.5ppm. Because of that,
it is no longer need for the Leo Bodnar GPSDO, that I have taken out. The extra 2.4 Ghz filter is also taken out, because
the CN-417 preamplifier has a filter onboard. Input filter has also been taking out, because it will be used in my new setup
for my caravan. Automatic Dish on roof of caravan, will do auto search for QO-100 – but this will be told of in a new description
in the near future here :-).