Raspberry pi for vlf

Discussion in 'The Low Bands - 630/2200 Meters - VLF' started by KG5ILR, Sep 22, 2019.

ad: L-HROutlet
ad: l-rl
ad: Left-2
ad: MessiPaoloni-1
ad: Subscribe
ad: L-MFJ
  1. KG5ILR

    KG5ILR Premium Subscriber QRZ Page

    Has anybody considered using a raspberry pi and a sdr dongle for a transcever combination.
     
  2. KK4CUL

    KK4CUL Ham Member QRZ Page

    I don't see why not, except possibly needing to limit the sampled bandwidth. The new Pi4 is relatively beefy, I'd try it with the 4GB RAM model, and make sure to use the USB3 ports. If you try, please let us know!
     
  3. KG5ILR

    KG5ILR Premium Subscriber QRZ Page

    Seems like it could be a possibility one of the pins has an rf output but I would imagine that a pretty good band pass filter would be needed. I will post what I figure out.
     
  4. KA9JLM

    KA9JLM Ham Member QRZ Page

    The WiFi external antenna connection is the only RF connection, Normally used when mounted in a metal case.

    I have a RPi3 that I use a SDR V3 with. It works fair, But the RPi3 has a lot of RF signals across the HF spectrum.

    Have Fun.
     
    K6CLS likes this.
  5. K3RLD

    K3RLD Ham Member QRZ Page

    KG5ILR and KA9JLM like this.
  6. WQ2H

    WQ2H QRZ Lifetime Member #214 Platinum Subscriber Life Member QRZ Page

    I've had good success using the TARP Hat and Direwolf with an RPi for HF Tx.

    One major issue with LF/VLF could be power out on the Tx side. You'll probably need a PA if you want to be heard. VLF antennas are also problematic.

    Assuming you're using an average short Marconi, which most do for LF (2200m), you'll see efficiencies at about .0005%. At VLF, say 30kHz, you'd see about .000002%

    My 400W TOP with a Hafler P3000 equates to about 200mW EIRP (before the load coil & variometer) into a short Marconi (40' vert w/ 100' hat) for 137 kHz.

    It's a tough nut - but it can be cracked. In any event, good luck !

    73
    Jim, WQ2H / WK2XAH
     
    KA9JLM likes this.

Share This Page