LW Broadcasting Tips and Broadcast History On 515 kHz and 535 kHz back in 1992 to 1996
Posted on December 9, 2012
I had a DX-380, one of the older type radios and I had the 200 In One lab kit tuned below 540 540 kHz. I was using a wire antenna less than 10 feet and a 9 volt battery. The DX-380 seeked to the lowest AM broadcast frequency between 510 kHz to 1710 kHz. I used to play new age music and rock music on that frequency, and when NAVTEX came on 518 kHz I moved to a temporary frequency of 535 kHz and back down to 515 kHz. The signal did not go that far and the way the transmitter was working is that the audio was connected to the output transformer the same way the speaker was inputed. I gave it up back in 1996 because there was no listeners on those frequencies plus I was new to broadcasting and 540 kHz is the highest long wave frequency below 550 kHz. I might go back when I get a better transmitter and do temporary transmissions and start LW broadcasting on the new lowfer’s frequencies of 165, 175, and 185 kHz. Now I feel better telling you experience about LW broadcasting and why I like LW radio that much. Longwave broadcasting goes far via ground wave propagation and has better bass response on audio frequencies, plus it’s a very narrow AM transmission than the AM broadcast band.
The circuit I used for 515 kHz was the 200 In One’s AM broadcaster circuit which is available in the 200 In One lab kit you can find anywhere online. Be sure to use a antenna less than 10 feet when transmitting down that low. Remember it’s just for experimentation. I hope that we can get lower down to 470 kHz to 520 kHz soon one day. Best time to do this is only in the daytime not always at night. You could probably go as low as 450 kHz to 520 kHz as long as your range is low and your antenna is short. And also do 160 kHz to 190 kHz.
If you want to do LW between 160 kHz and 190 kHz use the 9 kHz or 5 kHz increment frequencies or 10 kHz.
For 9 kHz : 162, 171, 180, 183, and 189 kHz
For 5 kHz : 165, 175, 185
For 10 kHz : 160, 170, 180, 190 kHz
Now since we don’t use 150 kHz to 160 kHz you could probbably start using them since it’s part 15.
The coils for LW are 5.0 mH, 4.7 mH, 3.3 mH, 2.5 mH – 160 kHz to 190 kHz (140 kHz to 300 kHz)
1000 uH, 470 uH 330 uH – 470 kHz to 520 kHz
Happy Holidays and Happy New Year!