# Solved: aliexpress 2 string passive adapter not working because Rpi connector was soldered on the wrong side of the board

**URL:** <https://rpi-rgb-led-matrix.discourse.group/t/solved-aliexpress-2-string-passive-adapter-not-working-because-rpi-connector-was-soldered-on-the-wrong-side-of-the-board/892>\
**Category:** Uncategorized\
**Created:** [October 12, 2024, 10:15pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/solved-aliexpress-2-string-passive-adapter-not-working-because-rpi-connector-was-soldered-on-the-wrong-side-of-the-board/892 "2024-10-12T22:15:09Z")\
**Posts on this page:** 1\
**Showing post:** 26

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [November 29, 2024, 12:07am UTC](https://rpi-rgb-led-matrix.discourse.group/t/solved-aliexpress-2-string-passive-adapter-not-working-because-rpi-connector-was-soldered-on-the-wrong-side-of-the-board/892/26 "2024-11-29T00:07:54Z")

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I replied to all 3 amazon sellers to give 1 star reviews and photos.  
Please rate your own seller on aliexpress with 1 star review too.  
In the meantime I received the blank board unsoldered, soldered it myself the correct way and it works fine.

With  
root@DietPi:~# ~/rpi-rgb-led-matrix/examples-api-use/demo --led-slowdown-gpio=4 --led-panel-type=FM6126 --led-rows=64 --led-cols=128 --led-row-addr-type=3 --led-chain=1 --led-parallel=2 --led-show-refresh --led-scan-mode=1 --led-pwm-bits=4 --led-pwm-lsb-nanoseconds=50 -D0 --led-pwm-dither-bits=1  
I get 350Hz on 2 ABC panels (128x128 total res)

 ![PXL_20241128_233330545](https://global.discourse-cdn.com/free1/uploads/rpi_rgb_led_matrix/original/1X/ff8fa11c014a9112cb31d6f0a60b53c70249452d.jpeg)

 ![PXL_20241128_233625566](https://global.discourse-cdn.com/free1/uploads/rpi_rgb_led_matrix/original/1X/654fafa05ddd79b6e4f945d07e99117ac685f101.jpeg)

This shows the correctly soldered board on left, then the incorrect one, the incorrect one I tried to unsolder (oh boy, what a mess), and a blank board with the connectors put in the correct way (not soldered yet)

 ![PXL_20241128_225531760](https://global.discourse-cdn.com/free1/uploads/rpi_rgb_led_matrix/original/1X/8a584b59a1da068112905d3a37923521a756353e.jpeg)

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