# TX LO leakage persists after stopping transmission and RX LED activates during TX-only sessions in LimeSuiteNG
**URL:** https://discourse.myriadrf.org/t/tx-lo-leakage-persists-after-stopping-transmission-and-rx-led-activates-during-tx-only-sessions-in-limesuiteng/13284
**Category:** LimeSDR
**Created:** [22 July 2026 08:18 UTC](https://discourse.myriadrf.org/t/tx-lo-leakage-persists-after-stopping-transmission-and-rx-led-activates-during-tx-only-sessions-in-limesuiteng/13284 "2026-07-22T08:18:15Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Prajwal](https://discourse.myriadrf.org/u/Prajwal)
#### Post date: [22 July 2026 08:18 UTC](https://discourse.myriadrf.org/t/tx-lo-leakage-persists-after-stopping-transmission-and-rx-led-activates-during-tx-only-sessions-in-limesuiteng/13284/1 "2026-07-22T08:18:15Z")
Hi,
I am using a **LimeSDR Mini v2.4** (Gateware **v3.10** ) with **LimeSuiteNG** built from source, and I have encountered the following two issues.
**Issue 1: TX LO leakage after stopping transmission**
After starting a TX stream (either a continuous single-tone signal or a modulated waveform) and subsequently stopping the transmission (either through the GNU Radio block or by calling the corresponding LimeSuiteNG API functions), the transmitter continues to radiate at the configured LO frequency. This behavior is confirmed using a spectrum analyzer.
The only way to make the transmitter actually go silent is to power-cycle the board.
**Issue 2: RX LED lights up during a TX-only session**
When running a TX-only application, where no RX stream is created, configured, or activated, the board’s RX LED still illuminates together with the TX LED for the entire duration of the transmission.
This behavior occurs even though the application never accesses the RX path. It appears that the RX chain is being enabled internally by LimeSuiteNG during a TX-only session, although I am unsure why this is happening.
Both of these issues are observed while using LimeSuiteNG built from source.
Is there a recommended approach to resolve these issues?
Any guidance would be greatly appreciated.
Thank you .
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### Author:  [@andrewback](https://discourse.myriadrf.org/u/andrewback)
#### Post date: [22 July 2026 08:47 UTC](https://discourse.myriadrf.org/t/tx-lo-leakage-persists-after-stopping-transmission-and-rx-led-activates-during-tx-only-sessions-in-limesuiteng/13284/2 "2026-07-22T08:47:46Z")
Tagging @ricardas
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### Author:  [@ricardas](https://discourse.myriadrf.org/u/ricardas)
#### Post date: [23 July 2026 08:27 UTC](https://discourse.myriadrf.org/t/tx-lo-leakage-persists-after-stopping-transmission-and-rx-led-activates-during-tx-only-sessions-in-limesuiteng/13284/3 "2026-07-23T08:27:46Z")
> [@Prajwal](#):
>
> stopping the transmission (either through the GNU Radio block or by calling the corresponding LimeSuiteNG API functions), the transmitter continues to radiate at the configured LO frequency.
Data streaming controls does not affect RF configuration.
The Tx LO remains powered on if the application does not disable it deliberately.
> [@Prajwal](#):
>
> The only way to make the transmitter actually go silent is to power-cycle the board.
No need to power cycle, you can just turn off transmitter with `limeConfig --txen=0`
> [@Prajwal](#):
>
> When running a TX-only application, where no RX stream is created, configured, or activated, the board’s RX LED still illuminates together with the TX LED for the entire duration of the transmission.
Even if Rx is not used, internally it’s always activated to keep track of hardware timestamps streaming.