450 Hz spacing noise + 53 Khz spacing noise on kiwisdr watterfall
Dear Kiwi community,
I am looking for advice regarding what appears on my Kiwisdr at the start of the 0 to 10 KHz band but can also have an impact higher up.
My Kiwisdr is located in the countryside, it is located in a house which I think is radioelectrically quiet.
The installation is composed as follows:
- 1 Kiwisdr connected to a 5 v power supply via the barrel port.
- 1 linear power supply (as much as possible), with a Talema transformer. https://fr.aliexpress.com/item/4000022726883.html?spm=a2g0o.order_list.order_list_main.15.21ef5e5bk1XbWI&gatewayAdapt=glo2fra
- 1 G5RV antenna 63 meters long approximately 12 meters from the ground for the central point.
- 1 GPS antenna with a small SMA extension to position it outside, and thus get the best possible view of the satellites.
No Ethernet connection to the internet box, but a wifi connection with a Tp-link dongle.
Between the antenna and the Kiwisdr input there is a Cross Country Wireless Receiver Front End Protection Unit (VLF/HF).
And yet I have just noticed that what looks like harmonics is present at the beginning of the band, and surely impacts my reception up to almost 30 MHz.
The signals identified are as follows:
0.68KHz - 0.45KHz spacing
1.13KHz - 0.46KHz spacing
1.59KHz - 0.45KHz spacing
2.04KHz - 0.45KHz spacing
2.49KHz - 0.46KHz spacing
2.95KHz - 0.46 KHz spacing
3.40KHz - 0.45KHz spacing
3.85KHz - 0.45KHz spacing
There is therefore around 450 Hz difference between the signals.
If I'm not mistaken it would be a harmonic of order 9 of my 230-240VAC power supply at 50 Hz?
But why would it be received on Kiwisdr like a radio wave?
Another thing that is quite surprising and quite visible in the 2 MHz band, there seems to be present on the waterfall another harmonic (perhaps related?), which appears every 53 KHz around (spacing).
Example: 2034.69 KHz
Have you ever encountered this phenomenon, and do you have any ideas or solutions to try to try to eliminate them?
It is sometimes easier to view the situation directly on the Kiwisdr concerned so here is the address of my Kiwisdr impacted by this problem.
With my best 73
F4FPR / K5AW