Page 1 of 1

I Q Supression

Posted: Thu May 07, 2015 9:33 pm
by Stan
I have noticed when running SDR# and SDRConsole V2 the I Q suppression doesn't quite get rid of the I Q spike when using SDRplay.
If I'm using a rtl-usb stick it's a non issue. Is there an issue with my SDRplay?
It's quite a hindrance when using SDRConslole and clicking on a frequency from memory.
Thanks,
Stan

Re: I Q Supression

Posted: Tue Aug 18, 2015 7:54 am
by jon
Hi Stan, I notice no-one (including us here at SDRplay) came back to you regarding the IQ spike. Hopefully, you will have found ways round it be now. Also for the benefit of others visiting the forum, here is our belated response...

What you describe sounds more like DC offset as opposed to I/Q imbalance. It is possible that your observations back in May predate the use of the ExtIO plugin when using SDR# - there was a short period before we moved to using EXTIO for SDR# when DC offset was a problem (due to changes made by the folks at SDR#) So this is definitely no longer a problem.

regarding use of SDR-Console, none of us here at SDRplay is an expert and we've actually found subtle questions as very well respoded to by the active SDRplay user community on https://www.facebook.com/groups/sdrplay/ (apologies to people who hate facebook!)

Alternatively please let us have more information/ screen shots at support@sdrplay.com

Jon

PS for HDSDR users there's a neat tutorial on the topic of IQ Imbalance on https://sites.google.com/site/g4zfqradi ... iq-balance

Re: I Q Supression

Posted: Wed Aug 19, 2015 9:37 pm
by F1BJB
Stan wrote: If I'm using a rtl-usb stick it's a non issue.
Hi
This depends of the RTL stick.
With the R820 tuner it is not.
With the ET4000 it is a problem.
On the other hand ET4000 has less and more prédictable spurious responses as it is zero IF.
HTH