I am using an RTL-SDR V3, with the long dipole antenna kit.
When I go into the Direct Q Sampling mode, I see AM frequencies, but no CB/hams, etc. In fact, the AM frequencies are reflected to higher frequencies, as well as other signals I am not able to identify.
I'd just like to know if there's anything I can do to fix this. I do realize that I do not have the correct HF antenna for the job, but I'd also like to know if there's anything hardware-related that is causing this reflection issue.
Thanks!
HF Signals not being received
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Re: HF Signals not being received
The reflections are just a known part of life with direct sampling mode on the RTL-SDR. To get rid of them you need to use a 14.4 MHz high pass filter.
For CB @ ~27 MHz, you should still be able to receive that in quadrature sampling mode, and that is not affected by reflections.
Ideally you would use a proper CB antnena. But to maximize the dipoles performance extend the long arms out to the max, and put it in a vertical position outdoors.
For CB @ ~27 MHz, you should still be able to receive that in quadrature sampling mode, and that is not affected by reflections.
Ideally you would use a proper CB antnena. But to maximize the dipoles performance extend the long arms out to the max, and put it in a vertical position outdoors.
Re: HF Signals not being received
Thank you, I'll try it!
Update: When I tune into the CB frequencies, the WFM stations are reflected down into its frequencies, so I don't see anything other than FM. Is there any way to fix this?
Thanks
Update: When I tune into the CB frequencies, the WFM stations are reflected down into its frequencies, so I don't see anything other than FM. Is there any way to fix this?
Thanks
Re: HF Signals not being received
You can buy a FM Filter from ehre: https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/
Mine Work but beware if you want to receive a Frequency above or below the FM Band the will not work.
I recommend to use a Airspy for CB and HF for me the work the best.
Mine Work but beware if you want to receive a Frequency above or below the FM Band the will not work.

I recommend to use a Airspy for CB and HF for me the work the best.