27-03-2019, 03:20 PM
A new arrangement is now in place with my Pi WSPR beacon.
It transmits on Tuesdays, Thursdays, Saturday and Sundays from 0000UTC to 2358UTC.
In local Brisbane time, it starts Tuesday at 10AM and finishes just before 10AM Wednesday morning, ditto Thursday at 10AM and finishes just before 10AM Friday morning. The weekend session starts 10AM Saturday and finishes just before 10AM Monday.
The continuous availability over the weekend is when many operators are not at work so may be looking for propagation information. The separate days nominally mid-week are just for general signal availability for generic propagation evaluation.
The previous post referred to the watchdog timer rebooting the Pi - but it doesn't have to with the current physical arrangement : the supply voltage is removed from the PAs with a heavy duty 12V automotive relay. The Pi continues generating WSPR on the 5 bands as previously on a 24x7 time basis and the PAs are only powered up as required on Tuesday, Thursday and over the weekend.
The PA power relay can quickly be set to be permanently off, on or via the nominated timing settings.
Thinking 'outside the box' solved the issue and only took a few minutes to implement.
PPS (next day) An interesting side effect noted : ZL1RS is still spotting the WSPR signal on 10MHz (and the only station doing so) even with the PA powered off. The SNR level reported is in the high -20's and low -30's in that state versus around zero to -2dB with PA power on.
I will have to try to do a measurement to gauge actual output power with the PA power off !!!
Expecting - by the WSPR figures - that the power will be about 25dB down on 2 watts - or - about 10mW.
To be confirmed ..
It transmits on Tuesdays, Thursdays, Saturday and Sundays from 0000UTC to 2358UTC.
In local Brisbane time, it starts Tuesday at 10AM and finishes just before 10AM Wednesday morning, ditto Thursday at 10AM and finishes just before 10AM Friday morning. The weekend session starts 10AM Saturday and finishes just before 10AM Monday.
The continuous availability over the weekend is when many operators are not at work so may be looking for propagation information. The separate days nominally mid-week are just for general signal availability for generic propagation evaluation.
The previous post referred to the watchdog timer rebooting the Pi - but it doesn't have to with the current physical arrangement : the supply voltage is removed from the PAs with a heavy duty 12V automotive relay. The Pi continues generating WSPR on the 5 bands as previously on a 24x7 time basis and the PAs are only powered up as required on Tuesday, Thursday and over the weekend.
The PA power relay can quickly be set to be permanently off, on or via the nominated timing settings.
Thinking 'outside the box' solved the issue and only took a few minutes to implement.
PPS (next day) An interesting side effect noted : ZL1RS is still spotting the WSPR signal on 10MHz (and the only station doing so) even with the PA powered off. The SNR level reported is in the high -20's and low -30's in that state versus around zero to -2dB with PA power on.
I will have to try to do a measurement to gauge actual output power with the PA power off !!!
Expecting - by the WSPR figures - that the power will be about 25dB down on 2 watts - or - about 10mW.
To be confirmed ..
Doug VK4ADC @ QG62LG51
http://www.vk4adc.com
This Forum is only going to be as interesting as the posts it contains.
If you have a comment or question, post it as it may trigger or answer the query in someone else's mind.
http://www.vk4adc.com
This Forum is only going to be as interesting as the posts it contains.
If you have a comment or question, post it as it may trigger or answer the query in someone else's mind.