It's all about the Software

Hello everyone, I am trying to resolve what to my is a mystery. Have a new RTL2838UHIDIR and the audio from SDR console V3, the latest one that I took yesterday, is always distorted. Whether I use SSB or Broadcast FM (yes I do know the difference), same results. I also know this SDR is the cheapest of all so I cannot expect Harry Potter.
Let me explain what I have done:

1) I have installed SDR Console V 3 latest in 3 different machines ( i5 and i7 laptops with latest WIN 10 x64 bit) and the third is a VM with VmWARE 16 Pro and WIN 10 latest.
2) In the same machines as mentioned above I also have installed the very latest HDSR software
3) Getting signals in 29Mhz or 2WS FM Stereo Radio station (101.7 MHZ) with HDSR is perfect, but with SDR V3 a total disaster............ HDSR provides a great RF signal in the front end and clear audio while SDR V3 signal is lower and audio is a disaster.

What am I doing wrong ? Is SDR V3 so different to HDSR ?

Hi Rick

Always post a full screenshot of the screen in the problem condition, so show a full screenshot (not edited or cropped) taken by the "screenshot" tool in SDRC:

https://www.sdr-radio.com/screenshot

If I had to take a guess it's that you have no AGC selected in the DSP panel and the manual gain is set too high:
Either reduce the Gain slider or select one of the AGC modes, Fast/Med/Slow.

Also check the RF gain settings and RF AGC settings in the "Home" ribbon bar radio settings at the top of screen, particularly Visual Gain:
My money is still on the audio DSP AGC settings though.

Dongles work just fine on SDRC. Loads in operation, so must be a setting.

Best

Max

Sorry, just remembered no AGC settings in BC-FM so can't be that in the VHF FM mode, but it could in SSB.

Just to be totally clear, you say "SSB or Broadcast FM (yes I do know the difference)" but just as a double check, I take it you do know that there are several settings for FM in SDRC? In particular, the correct setting for Broadcast FM is (logically) BC-FM and not W-FM as is often thought:
W-FM will also give horrible audio distortion on BC FM sigs. Many reports on here of people trying to receive BC-FM on the W-FM mode setting. Apologies if that's what you meant by "yes I know the difference".

Max

Max, thanks. I can guarantee that I do know the difference in Broadcast. Been in TX radio and TV in Australia since 1998.

I will continue testing. Yes in SSB (L or U side bands) AGC slow is needed, I know that too.

We put again, both software in a 4th computer that my son has. He uses a Hack RF 1 to TX DVB-T and DAB +. HDSR works like a charm, this one does not even recognize HACK RF at all.
I also tuned to 28160 CW beacon, HDSR gets the signal with an S1, the other is dead, no RX, is deaf.

In all honesty, I am surprised. HDSR is a 1.9 Megabytes package and the other close to 160 Mgbytes. Interface graphics are very nice but.................I need to RX.

Cheers

Screen shot

RickMarBen wrote: ↑Tue Sep 14, 2021 3:45 amScreen shot

Start the radio,

Then take a screenshot!

Rick

Yes, to reiterate what Simon says, the screenshot has to show the radio in the problem configuration, i.e. radio started and receiving distorted audio.

A great many copies of SDRC (thousands I would guess) in operation and many of those using RTL-SDR including myself, receiving perfect audio quality at expected signal strengths. It can only be a config issue (or compatibility issue - unlikely) if the same RTL works OK on other software but not on SDRC. For info my RTL stick is RTL-SDR.COM V3 and works perfectly (within it's expected limitations), far better than it's price would indicate in fact.

For info Hack RF is supported by SDRC but RX only. No TX support planned:
https://www.sdr-radio.com/hackrf

Just in case you want to check over some basics for RTL stick with SDRC on see here if you did not already go over it:
https://www.sdr-radio.com/rtl-dongles

Just to clarify, I was not querying your knowledge of Broadcast FM, simply clarifying the correct mode setting inside SDRC as many try to receive BC-FM with mode in the W-FM mode, myself included when I first used SDRC. I also worked in broadcasting 1980-2009 so hardly a novice but we can all make simple errors sometimes especially on unfamiliar software!

Max

Hi Rick, we like to help you but you're having a problem with FM broadcasts audio so we can't help you with a screenshot of a 26Mhz band part in USB and a radio that is not running. Please have a look at my screenshot as a example. (small antenna so signals are not big)
regards, Leon

As side notes:
For RTLSDR dongles the low frequency range of the tuner is not necessarily guaranteed. 29 MHz is a little iffy but "usually works", it may be overloaded by the very nearby 28.8 MHz oscillator in the dongle. You may find the direct sampling mode won't work well because that is very close to the dongle's crystal oscillator frequency of 28.8 MHz.

Without a picture showing dongle settings, including a picture showing the sample rate you have set up, you're not going to get more help than above because we lack information needed to provide it.
{o.o}

OK, this is it with dongle working in 28260.