# Momentary Tx when changing frequencies

**URL:** <https://discourse.myriadrf.org/t/momentary-tx-when-changing-frequencies/3488>\
**Category:** LimeSDR\
**Created:** [13 October 2018 21:07 UTC](https://discourse.myriadrf.org/t/momentary-tx-when-changing-frequencies/3488 "2018-10-13T21:07:59Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Kc7noa](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/kc7noa/32/144_2.png) [@Kc7noa](https://discourse.myriadrf.org/u/Kc7noa)\
**Post date:** [13 October 2018 21:07 UTC](https://discourse.myriadrf.org/t/momentary-tx-when-changing-frequencies/3488/1 "2018-10-13T21:07:59Z")

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I don’t know if this is a problem with SoapySdr or the SDR program i’m using … or Lime’s drivers for Linux …

I use LimeSDR-usb on Ubuntu 18.04 with SdrAngel and when ever i change frequencies with the Tx playing and mute on (the icon with the -120DB) showing … i get a momentary Tx of signal … i have not  
used FM and no other mode …

Just wondering if any other FM SSB AM sdr programs show the same issue …

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**Author:** ![yindra](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/yindra/32/1901_2.png) [@yindra](https://discourse.myriadrf.org/u/yindra)\
**Post date:** [15 October 2018 14:40 UTC](https://discourse.myriadrf.org/t/momentary-tx-when-changing-frequencies/3488/2 "2018-10-15T14:40:17Z")

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This sounds like the same issue:

> [@Strange TX burst before intended transmission - LimeSDR-mini](https://discourse.myriadrf.org/t/strange-tx-burst-before-intended-transmission-limesdr-mini/3485/5):
>
> It may be due to the slow interface: Try if it gets better by using cacheCalibrations: args = dict(driver='lime', cacheCalibrations='1') self.sdr\_device = SoapySDR.Device(args)

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**Author:** ![ricardas](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/ricardas/32/86_2.png) [@ricardas](https://discourse.myriadrf.org/u/ricardas)\
**Post date:** [15 October 2018 20:27 UTC](https://discourse.myriadrf.org/t/momentary-tx-when-changing-frequencies/3488/3 "2018-10-15T20:27:48Z")

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It might be just Tx calibration being executed after each frequency change.