Bakon 950D "Extra Crispy" mod (19->24 Volt)

[Daijoubu]

120V and yes, but sadly the PSU is now dead lol.

They miswired the hot and neutral on the plug, so the switch was only cutting off the neutral.. I had it plugged in while working on it (to ground the tip), the controller was powered by another PSU and was planning to try replacing R10 with 100k but then I touched it and it shorted it to ground and it took some traces and D4 with it, I tried to bodge wire the missing tracks but no go, it's blowing the fuse now and there's a short somewhere.

Maybe the rectifier bridge is toasted? I'm now just tempted to use an external PSU and call it a day lol or maybe buy an off the shelf open frame 24V PSU, but it's not economically sound, may as well upgrade to an STM32 OLED T12 station instead hah

[Daijoubu]

Yep, the full bridge rectifier is kaput

[pyden]

Did this mod today with my Yaxun YX-8034, it looked identical to the bakon 950d inside except the yaxun one has a way simpler power supply, no OVP, just had to put a 10~k resistor in parallel with another resistor close to a SOT-23 package no-name component (can't find the part number anywhere on the internet), which was connected to the optocoupler on the output side to get the PSU up to 24v.

After that i just did the 5v1 zener diode modification to the controller board since this one *is* identical to the one on the bakon 950d

Working perfectly after recalibration!
Might put a little fan inside to keep it cool since i can feel it get warm from the outside, and also might mod it to turn off/go in standby when in the stand later on, since the controller board has an atmega8 that might be easy to program

Also noticed the controller board has a row 6 unpopulated through hole pads, considering one of the pins on it is connected to one of the buttons (can't see where the other tracks go), i'd assume it's made to be fitted with a rotary encoder, the case has a hole in there and everything right in front and above the pads so a module could fit in perfectly, might look into that.

[stj]

6 pads, 6wires used to program the AVR controller.

[pyden]

Originally Posted by stj

6 pads, 6wires used to program the AVR controller.

oh-
that makes sense too yeah, neat.

still find it weird that they left that hole in the case tho

[tmks2]

Originally Posted by stj

so,
R11 - 27k(OVP) change to 20k 0805
R24 - 4.42k(voltage reference) change to 3.4k 0805

i'v been running 24v for several years and not damaged the optocoupler
the caps you need are panasonic eeufs1v102L

you need a 5v1 zener diode on the control board,
here is a couple of photo's - with a track cut and then bridged by the diode

That's all? is this enough to reach 24V?