Hello Marcin,
generating 2 counterphase sine signals can be easily done with a soundcard.
But as you are speaking of duty cycles I assume that you want a square wave signal and there you are limited by the sample rate
of the soundcard. These days 192kHz soundcards are easily available, was means a sample each 5.20833.. microseconds.
For 8970Hz the closest frequency is 8727.2727.. Hz (192000/22).
If you want to use a soundcard your best option may be to generate sine signals and use a hardware discriminator to convert them
to a square wave.
If I am not mistaken you could use DL4YHF's Spectrum Lab software as it has a test generator option.
73, Rik ON7YD - OR7T
Hi All!
We’re building an 8,970kHz VLF transmitter at SP2KDS club.
We almost have everything in place:
What we still need is a generator to feed the transmitter. Required parameters are the following:
- 8,970kHz frequency
- regulating range +-0.05Hz
- adjusting duty cycle of 5 to 45%, at 5% for two signals at the same time
- two signals shifted by 180 degrees
A friend of mine has promised to build it but it’s been over a year now and nothing has happened.
Is there a software which would use a soundcard with the aforementioned parameters?
73! Marcin SQ2BXI
