# Squelch and the KSHT sounds **URL:** \ **Category:** GNU Radio\ **Created:** [July 13, 2014, 1:07am UTC](https://www.ruby-forum.com/t/squelch-and-the-ksht-sounds/230922 "2014-07-13T01:07:04Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![addis\_a](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/c4cdca/32.png) [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Post date:** [July 13, 2014, 1:07am UTC](https://www.ruby-forum.com/t/squelch-and-the-ksht-sounds/230922/1 "2014-07-13T01:07:04Z")
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**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [July 14, 2014, 11:33am UTC](https://www.ruby-forum.com/t/squelch-and-the-ksht-sounds/230922/2 "2014-07-14T11:33:32Z")
The ‘Power Squelch’ block in GRC is my favourite and I would recommend using this one. Have a look at the following GRC flow graph for a working example that uses the power squelch block: [https://raw.githubusercontent.com/m0mik/scanoo/master/apps/scanoo.com\_rx.grc](https://raw.githubusercontent.com/m0mik/scanoo/master/apps/scanoo.com_rx.grc) Note that the ‘Ramp’ setting is the number of samples it takes at the start and end of a detected signal for the volume to go from 0% to 100% and 100% to 0%, and the ‘Alpha’ setting is the signal average alpha just like in the FFT WX GUI widget. 1 disables the averaging and will give you the fastest cutoff at the end, however if you have signal flutter then the audio will be choppy. I’d recommend using between ‘0.01’ and ‘0.001’ in the power squelch block for the ‘alpha’ setting. Mike – Mike J. M0MIK BSc MIET Ettus R. Technical Support Email: removed\_email\_address@domain.invalid Web: [http://ettus.com](http://ettus.com)