From April 2020 Radio Northern Europe International broadcasts are broadcast with pre-emphasis 😄
What are the reasons for making this change?
This change allows the higher frequencies to push through the noise floor when the signal is weaker which is ideal with for the transmission power we are using. Most big shortwave broadcasters are using similar techniques on their broadcasts.
Here is a picture of a S5-S7 signal with almost all the audio coming through the noise:
Here is an example of how much more audio gets through the noise:
What does this mean for receiving the show?
- If you have a portable or other dedicated radio you don’t need to do anything. Most dedicated radios have built in de-emphasis. We will sound brighter and much less muddy. If your radio has a treble control, adjusting that might help if it is too bright for you.
- If you use your own SDR, your software might not have a de-emphasis or EQ system built in. 😱 This can be remedied by using an EQ on a recording you make from the SDR or adjusting the EQ on your sound card.
- If you use a Kiwi SDR, follow the steps below.
How do I get it sounding more ‘normal’ on a Kiwi SDR?
In the Kiwi SDR control box we are going to click on “Audio”
Click the drop down box next to volume that says “off”
Select 50us or 75us. Whichever one sounds better to your ears is the right one for you. 🎶
That’s about all there is to say on de-emphasis, it’ll be really interesting to hear your feedback about our new processing method!
Remember to always use SAM when available for the most stable sound!