WSPR (whisper):
Weak Signal Propagation Reporter.
Remember, the USB dial frequency is 1.5 KHz lower than the transmitted frequency (the centre frequency). You need to take the centre frequency you want to decode and subtract 1.5 KHz to calculate the Dial Frequency for USB.
Formula:
USB Dial Frequency = TX centre Frequency – 1.5 KHz
Example: Dial Freq = 5.250 MHz – 1.5 KHz = 5.2485 MHz
WSPR decoding is done +- 100Hz of the centre frequency.
It is usual to quote the Centre frequency and the operator needs to calculate the correct dial frequency.
WSPR on 12 metres:
I’m now using WSPR with my IC-7300. My first attempt on 12 metres was most successful. Here is a map showing where I was being heard by stations as far as South America. My power was about 3 Watts. The antenna is a 5/8 vertical tuned for 10 metres so the SWR would have been very high. I cheated by using the radio’s auto ATU to keep the TX happy.
I’ve been having a great time with WSPR on various bands. There was a station in Greenland on 4 metres. I couldn’t hear him but he did show up on the WSPRnet map. You don’t have to be a licensed radio amateur to use the map or the WSJT computer program. You can login as a short wave listener. The stations you hear will be shown with your icon on the map.
WSPR on 10 metres:
This was on 10 metres during the afternoon of 18/11/24 with the IC-7300 power down to 0% which I believe is around 1.5 Watts. I was being heard in North Carolina, Florida, Tennessee, Mississippi and other places. The antenna is a 5/8 vertical two metres AGL.
WSPR on 15 metres:
It’s truly amazing just how far a couple of Watts will travel on this band. I was using my doublet on this band, hardly an ideal antenna, and I was heard thousands of miles away.
Top Band – 160 metres:
Out of interest, I’m trying WSPR on top band. My aerial is a doublet, 30 metres top at 10 metres high… obviously not designed for 160 metres. In fact, it’s about 49 metres short! However, having a decent ATU, I can get 1:1 SWR. By the way, you can load a six inch nail on top band and get 1:1 SWR with a decent ATU. But, obviously, it will be a useless antenna. I’ll be testing after dark tonight (17/11/24) on 1.8366MHz. Power will be about 5 Watts to begin with. Will I be heard in America?
I wasn’t heard in America but I did reach Iceland and Turkey. I’m now using a 30 metres long end-fed antenna. The results were much the same as the doublet so I will be lengthening the end-fed in the hope that it will improve things.
VLF:
I tried my Miniwhip active antenna on two VLF frequencies. I heard F6KPL on 474.200KHz. I also monitored 136KHz but heard nothing.