# LimeSDR Mini - RMA Authorisation Request

**URL:** <https://discourse.myriadrf.org/t/limesdr-mini-rma-authorisation-request/6823>\
**Category:** General Discussion\
**Created:** [4 January 2021 15:12 UTC](https://discourse.myriadrf.org/t/limesdr-mini-rma-authorisation-request/6823 "2021-01-04T15:12:11Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![DaveG8GKQ](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/daveg8gkq/32/2361_2.png) [@DaveG8GKQ](https://discourse.myriadrf.org/u/DaveG8GKQ)\
**Post date:** [4 January 2021 15:12 UTC](https://discourse.myriadrf.org/t/limesdr-mini-rma-authorisation-request/6823/1 "2021-01-04T15:12:11Z")

</div>

An Amateur Radio friend of mine (who is very experienced in analogue video and RF, but a newbie to SDR) purchased a LimeSDR Mini from Mouser in August, and has used it successfully for Digital Amateur Television transmissions on 437 MHz. However, when he came to use it for satellite transmissions on 2409 MHz, he found that the output was much lower than expected (although the spectrum is as expected). He has passed it to me to compare with other LimeSDR Minis and ask for an RMA.

Using the Portsdown DATV transmitter, the output on various frequencies is as follows:

```
146 MHz 437 MHz 1255 MHz 2409 MHz 3000 MHz
+3.0 dBm +4.5 dBm +4.2 dBm -12.4 dBm -17.2 dBm

```

A known good LimeSDR Mini, connected to the same hardware and test rig gives:

```
+5.9 dBm +5.7 dBm +5.8 dBm -2.0 dBm -12.5 dBm

```

It appears to me that the high band output circuitry has a fault, and if I (incorrectly) select the high band output at 1255 MHz, the output is still 10 dB lower than a good LimeSDR Mini with the same settings.

It also fails LimeQuickTest (using the latest LimeSuite, with nothing connected to the SMA sockets, and straight from cold):

> pi@raspberrypi:~ $ LimeUtil --update  
> Connected to [LimeSDR Mini [USB 3.0] 1D587F46DB6271]  
> Existing gateware is same as update (1.30)
> 
> Programming update complete!  
> pi@raspberrypi:~ $ LimeUtil --make  
> Make device  
> Device name: LimeSDR-Mini  
> Expansion name: UNSUPPORTED  
> Firmware version: 6  
> Hardware version: 3  
> Protocol version: 1  
> Gateware version: 1  
> Gateware revision: 30  
> Gateware target: LimeSDR-Mini  
> Serial number: 0x1d587f46db6271  
> Free connection… OK
> 
> pi@raspberrypi:~ $ LimeQuickTest  
> [TESTING STARTED]  
> -\>Start time: Mon Jan 4 14:39:18 2021  
> -\>LimeSuite version: 20.10.0-unknown
> 
> -\>Device: LimeSDR Mini, media=USB 3.0, module=FT601, addr=24607:1027, serial=1D587F46DB6271, HW=3, GW=1.30  
> Serial Number: 1D587F46DB6271  
> Chip temperature: 20 C
> 
> [Clock Network Test]  
> -\>REF clock test  
> Test results: 38372; 51569; 64766 - PASSED  
> -\>VCTCXO test  
> Results : 6710991 (min); 6711146 (max) - PASSED  
> -\>Clock Network Test PASSED
> 
> [FPGA EEPROM Test]  
> -\>Read EEPROM  
> -\>Read data: 13 0A 15 13 0A 15 02  
> -\>FPGA EEPROM Test PASSED
> 
> [LMS7002M Test]  
> -\>Perform Registers Test  
> -\>External Reset line test  
> Reg 0x20: Write value 0xFFFD, Read value 0xFFFD  
> Reg 0x20: value after reset 0x0FFFF  
> -\>LMS7002M Test PASSED
> 
> [RF Loopback Test]  
> -\>Configure LMS  
> -\>Run Tests (TX\_2 → LNA\_W):  
> CH0 (SXR=1000.0MHz, SXT=1005.0MHz): Result:(-24.3 dBFS, 5.00 MHz) - FAILED  
> -\>Run Tests (TX\_1 → LNA\_H):  
> CH0 (SXR=2100.0MHz, SXT=2105.0MHz): Result:(-20.8 dBFS, 5.00 MHz) - FAILED  
> -\>RF Loopback Test FAILED
> 
> =\> Board tests FAILED \<=
> 
> Elapsed time: 2.77 seconds

There is no sign of any physical damage (indeed the unit came to me mounted in an aluminium die-cast box for protection). Is there anything else that you would like me to try, or can you authorise an RMA?

Thanks

Dave, G8GKQ

---

<div class="post-metadata">

**Author:** ![andrewback](https://avatars.discourse-cdn.com/v4/letter/a/22d042/32.png) [@andrewback](https://discourse.myriadrf.org/u/andrewback)\
**Post date:** [5 January 2021 10:44 UTC](https://discourse.myriadrf.org/t/limesdr-mini-rma-authorisation-request/6823/2 "2021-01-05T10:44:50Z")

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It does indeed sound like damage and I cannot think of anything else. @Zack, would you like to suggest anything before authorising RMA?

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<div class="post-metadata">

**Author:** ![Zack](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/zack/32/89_2.png) [@Zack](https://discourse.myriadrf.org/u/Zack)\
**Post date:** [5 January 2021 10:56 UTC](https://discourse.myriadrf.org/t/limesdr-mini-rma-authorisation-request/6823/3 "2021-01-05T10:56:30Z")

</div>

Hi @DaveG8GKQ,

The RF channels are lower output for sure. But these are not dead. Nevertheless, something is wrong. Would suggest to contact the seller for replacement.