Replicate Main LED on Bluetooth Amplifier Board with Wifi Up2stream Amp V4

Does anyone know how to replicate the Main LED on the Amplifier Board.


I can’t really work it out from the manual. I would expect a 4 wire R,G,B & GND. WHITE would be when all Red, Green, & Blue are 3V3 !


So basically my questions are

  1. Has anyone done it ?
  2. What type of LED do I need ?
  3. What would be the wiring arrangement ?

Many Thanks in Advance, Kevin

The common firmware for this board only support RGB LED, so all the RGB line would be activated for white. And for the PINs of extended, we reserved it for the condition of customizing firmware. I’ll find a way to configure this via API commands.

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Same problem with a replication LED for the new Plate Amplifier. The JST-PH connector offers 4 pins: 1 (common anode) with 3.3V DC (VCC) and 3 for the cathode of R,G,B LED. So a 4 pin RGB Led (5mm) could be used to indicate the selected source on the front side of a speaker. Unfortunately this does not work because this common anode LED needs a Vf (forward voltage) of about 3 VDC to 4VDC (blue) to go into conduction. Even an SMD chip three-color LED has a Vf of 3.3 VDC and will not conduct either. The 1K current limiting resistor suggested in the manual will then not have to limit much more because there is simply no current.

Only some red Leds (low current) do conduct (Vf < 3 VDC) and light up sufficiently if a much smaller series resistor is used (VCC-Vf 1.2V/220R = 5.4 mA).

Moreover, the 3 pins (R,G,D) appear to be pulled to Gnd simultaneously, regardless of the choice of source. The Wifi module however needs a 5 VDC on pin 1,2. Without documentation it is risky to experiment further.

Why is that JST-PH 4 pin LED connector provided and how can it be used safely?

The connector for an IR receiver does work fine (with a standard type 38 Khz carrier 940nm wavelenght) and the Arylic remote control.


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Got it working with the Bluetooth Amplifier Board with Wifi Up2stream Amp V4 using the following wiring.

Photographs of Wiring can be found in this post:-

Nobby Box IR Remote & Status Lamp Upgrade

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Hi Kevin!

Thanks for your sharing.
I’m working on a 2.1 amp and this diagram doesn’t seems to work for me.
I’m looking to deport led’s to an RGB Led.
Have you tried this wiring on other board?