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RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 10:47 am
by Mick2000
#Frustrated Can anyone HELPppp!!!!!! I am new to all this and very frustrated. I have just purchased the RSP1 but cannot receive anything at all except white noise :D What I am doing wrong? I am using SDRUno.

If I use my old analogue scanner - RadioShack Pro 74 I receive the frequency 133.800 quite clearly, yet when I connect the same antenna to my RSP1 and type in 133.800 I don’t receive any transmission, just crackling noise. How is this happening? Unplug the BNC and plug it in the Pro74 i receive transmission.

Any advice is much appreciated. I have attached a video so you can see the settings of SDRUno.

Thank you in advance.

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 12:13 pm
by OH2BUA
Hi,

it's aviation traffic you are about to listen?

1) You have AM mode and 6000 (Hz) filter bandwidth selected?

2) As RSP1 does not accept BNC connection, you for sure have an adapter or a pigtail for matchmaking. Check that there is a pin to match the hole in RSP1's SMA connector. So that you have a true male/female pair.

3) Check that you are tuned to 133.800 MHz, not 133.800 kHz. Should read 133.800.000

Hope some of these helps.

By the way, I can't see any attached video.

73, Jukka

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 12:38 pm
by Mick2000
Thanks for the information.

I was listening on kHz not MHz changed it and now can receive frequency.

Not sure what you mean by AM on 6000 filter bandwidth If you could expand that would be appreciated.

I have the correct fitting on the RSP to take the BNC.

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 3:01 pm
by g1hbe
Select AM mode and the 6 KHz bandwidth setting. Or wider if there are offsets in use. Also make sure your receive frequency and the displayed LO frequency are NOT the same. If they are you will get weak reception and distortion. This catches out a lot of beginners!

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 3:15 pm
by Mick2000
Andy how do I ensure that my receiving frequency and the displayed LO frequency are not the same? Thank you.

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 4:15 pm
by g1hbe
Simplest way is to click the tuning cursor to one side of the centre LO frequency, then type in your required frequency (or tune there with your mouse wheel). You can hover your mouse over the digit you want to change and then use the wheel.

Re: RSP1 not detecting frequency

Posted: Tue Sep 11, 2018 4:45 pm
by Mick2000
Thanks Andy I will give it a try.

Mike