Thank you!
Please add this to your guide:
Add possibility to use suspend mode when using CoreELEC on USB device
This modification do require advanced user skills by using a solder iron.
The USB 5V are controlled by a step-down converter. This converter do have a enable pin.
By pulling this pin high to Vin it get enabled. By pulling the enable pin low the converter is disabled.
The enable pin is controlled by the device u-boot by pull high/low a GPIO pin.
This GPIO pin will drive a simple Mosfet what will pull down the enable pin of the converter if set.
So when the Mosfet is removed the USB 5V are permanent on.
Homatics is not able to remove the code line in u-boot source what do set/clear this GPIO pin because it’s out of their control.
Location to find the Mosfet (Homatics Dune R4 Plus, PCB 2022.3.25, SMB.280.08D)
Mosfet assembled
Mosfet removed
The left upper pad is hard to get released as it’s the ground pin. So the heat of the solder iron is quickly removed.
Use at your own risk: can void warranty!
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@Portisch no problem adding it to the guide ,but i was thinking to create another topic which would be modding related .
Or maybe just add a section here,for modding (which will also warn users about warranty loss when doing such mods) .
What do you guys prefer ,first option or second ? 
Edit: I also wonder if this mod has other “side-effects” (eg. will this affect the USB HOST mode when used with Android ?)?
However ,i will try this mod ASAP and report if there are any down sides .
Edit 2: There’s also a bad news in your post,the fact that u-boot is out of Homatics control . 
Edit 3: Modding section added to this guide and @Portisch mod was added .
IR receiver mod for the Homatics Box R 4k Plus (not DuneHD ) should be next.
Nice finding. Just some comments:
- Mosfet is a standard NPN Transistor (mmbt3904lt1). Just in case anybody wants to re-assemble later.
- Instead of removing complete Transistor (red), as alternatives:
- lifiting one leg (green) -or-
- removing the Resistor (orange) -or-
- short-circuit the two contacts (yellow) -or-
- move the Resistor from (orange) to (yellow) position (technically most clean way)
will have the same effect.
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Floating base is not a good idea.
Only way would be to lift up the single pin of the transistor. A floating collector doesn’t matter and don’t bring any harm to the device.
This is a Transistor, therefore a floating Base (orange) is uncritical, as there will be no Base current to be amplified. But agree, this is not state-of-art engineering, more a pragmatic workaround.
Anyone still being concerned about floating Bases (orange), can tie the Base to GND (yellow)
My IR Receiver Diode mod.
With this mod, I can use the box under CE, with IR mode, include ON/OFF the box with original remote. This mod voids the warranty, use in your own risk.
The (1). I soldered an IR diode (CHQ1838** type, but others maybe good too)
in the indicated place.
– Later, due to the better signal, I did not cut the diode’s legs on the second test, but bent them in a double L shape (4).—
Before the Diode, I thinned the material of the housing from the inside with a small ball grinder (3). Thus, even under CE, the remote control works in IR mode, there is no problem like with the Bluetooth connection, there is no need to pair.
For IR mode use this remote.conf file, place your root of CE pendrive, or config folder, in CE.
2 Likes
frodo19, so in front of LED there is no direct hole? Just plastic has less thickness? Smart!
Please make a new pull request here: GitHub - CoreELEC/remotes: Repository for AmRemote & Meson IR Remote Controllers
So other users easily can find it, thx.
@Betatester is currently offline because of private reasons. I will merge the PR than.
Yes, very thin… 
Not seen any hole…
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@Portisch pull request added.
Months ago when i did this IR mod ,i had to drill a small hole in front of the receiver ,otherwise it had very poor reception .
Later ,after Frodo019 did the mod and said that he only used the grinder to make the plastic thiner ,i tried it on a second mod,but it was great only without the top cover.
The top cover holds the LEDs PCB and that goes exactly on top of the IR Receiver ,which imho not only blocks the signal but also create interferences (even the mod which has the hole in front of the IR receiver is affected by the top cover ,but less).
No issue here, 4=5 m distance still good. I have dune version too with built IR, and this mod equal or better.
Maybe i got a bad receiver or the plastic is not thin enough ,but without the top cover you don’t even have to point the remote to the receiver ,so something is definitely messing with the IR.
And AFAIK ,led circuits are pretty "noisy ".
Did you use the same IR receiver Diode as Frodo19 (CHQ1838), or a similar one?
There are types with different center frequency available, which affect IR sensitivity.
Also there are types w/o metal case, which have worse EMI immunity (or lower IR sensitivity).
You may check if it’s really the LED pcb by:
- switching off , or full brightness white, there should be no EMC emissions
- half brightness white is the worstcase scenario for EMC emissions
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I tried with VS1838b and CHQ1838 (which seem to be used on DuneHD ).
However i’m not sure if they were original or some poor clones .
I think i tried with the LEDs disconnected ,but i don’t remember the outcome.
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Looks like this mod breaks wol.
WOL is because of the missing BL301 support not supported at all. Same as the USB power feature and IR remote after resume to.
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