Re: Computer fan noise and maintenance
I'm sorry for 'bumping' my own post but I'm a little worried about this one (that 2t oil will gum up unlike 4t oil?), I dont want to damage 135mm fan which is hard to find/replace replace (there is not a single one 135mm in local stores). Thanks....
BadCon
Member
Last Activity: 09-23-2023, 11:31 AM
Joined: 01-26-2017
Location: Zagreb
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Re: What are these white patches on top of the metal parts of this board?
AFAIK, actually opposite of what you wrote. Its like thin thermal pads between TO-220 and heatsinks which transfer heat and not electricity, just thicker.
Thermal pads transfer heat from small surface, onto bigger surfaces like metal shield in LCD monitors, to offer better cooling. On small passive-cooled netbooks, thermal pads are often used to transfer heat from processor and chipset to metal plate under keyboard.
If LCD housing is metal, and manufacturers doesnt wanted to conduct heat...Last edited by BadCon; 01-28-2017, 09:51 PM.Leave a comment:
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Re: What are these white patches on top of the metal parts of this board?
I'm seeing just two of them.
And thats thermal pads for sure.
Pretty common in laptops to transfer heat from chipset/vrm/vram.
I have seen them mostly in white color, but also blue (Arctic thermal pads).Leave a comment:
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Re: Computer fan noise and maintenance
I found Arctic fans (their patented FDB bearings) is what I think sealed. I dissasemble them using force to remove blades from frame, clean it and put a drop or two of oil on fan shaft. Push it back altogether and works fine. Is that a proper way to relubricate them or that kind of fans should not be dissasembled (as I read that FDB should not be changed?).
Recently a 135mm fan (I suppose ball bearing, because PSU is good quality FSP made) in my PSU start to make annoying noises, so I cleaned it and lube...Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
I was looking to replace power board electrolitic caps too, but as their values for Low ESR versions isn't available in local store, I just closed it as I dont want to order, paying shipping, and wait for caps from online stores outside country. I doubt that 10mF (or so) electrolitics caps can be problem in control board. Monitor is LED so doesnt get hot and dont have much power on hours so I think caps in power supply will be fine for workhours to come.
Oscillating what? As i said earlier, after...Last edited by BadCon; 01-27-2017, 07:59 PM.Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
Im glad it worked at just under 1.6V, because if its not I would suspect circuit takes too much current so Vreg protection kicks in and lower the voltage.
For 0.2% regulation, I dont know. Im not that good, but i hope 0.4% will be enough good for operation.
I just purchased LD1117 1.8V SOT223 today. Datasheet says its max load regulation is 0.4% and line regulation 0.2%.
First I connected it with crocodile test wires, output voltage drops exactly as with LM317, but unit works.
I go ahead...Last edited by BadCon; 01-27-2017, 11:03 AM.Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
I bypassed 4.7Ohm resistor and connect LM317 directly to 5V rail.
Vin is 5.10V
Vout when screen standby 1.80V
Vout when screen turned on 1.56V
Current from 5V rail to LM317 Vin = 152mA
Current from LM317 Vout screen in standby = 1.1mA
Current from LM317 Vout screen turned on = 62mA
Also I try to connect LM317 through 4.7Omh resistor, output voltages are the same, but input voltage is 4.41V (5.10-4.41V is 69mV voltage drop through resistor).
I made few...Last edited by BadCon; 01-26-2017, 11:39 PM.Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
Big 4.7Ohm is connected in serial with input of 1.8Vreg, to 5V rail. I already tried to short out that resistor, no luck. Why is that resistor there, if you can learn me something? If AP2114 max is 6V, and circuit consumes just 60mA, there wont be that much of power dissipated in voltage regulator.
As i stated above, for testing purpose I connected LM317 directly to 5V input (avoiding that resistor) and measuring the 1.8V output current from LM317 regulator. Measurements says about 60mA. Not even near 800mA....Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
I though problem was in MCU, which drives excessive current and therefore drops voltage of regulator (as MCU gets really hot together with R707 4.7Ohm resistor which is in series with input of 1.8Vreg), but it was not the problem.
Checked resistance as sugested, seems almost identical for two Vregs.
Maximum input voltage for Vreg is 6V, minimum is 2.0V, so it should work at 1.93VDC i measure before.
I also tried to short out 4.7Omh resistor which is connected in serial with Vin of Vreg and 5V...Last edited by BadCon; 01-26-2017, 07:04 PM.Leave a comment:
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Re: Philips LED 226V3L no sign of life, wont power on, no led
Thanks for the reply. I already wrote DVC reading of white PSU connector, here are detailed measurements I made now:
Without main control board connected:
DIM, N/P, ON/OFF, GND, VOL, MUTE reads 0VDC
5V reads 5.14VDC (thats without load/main board connected).
With main board connected to power board:
DIM reads 80mVDC
ON/OFF reads 85mVDC
N/P, GND, GND, VOL, MUTE reads 0VDC
5V reads 5.04VDC
Upper voltage regulator is GH12D 1.8V:
Input connected...Leave a comment:
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Philips LED 226V3L no sign of life, wont power on, no led
Hi, I'm new on this forums and I've already fixed several LCDs, PSUs and MBOs replacing bad capacitors. But, I'm unable to fix this LED screen by myself.
LED monitor is Philips model 226V3L, with AU Optronics M215HW03 V1 panel.
No sign of life after connecting to mains. Worked flawlessly, one day just wont power on.
Power supply board is 715g4497-p03, no bulging caps.
connectors on it are CN804 6pin which goes to LED panel (probably backlight);
and CN902 which connects to control mainboard, pins: DIM, ON/OFF, GND, GND, 5V, 5V, VOL, MUTE. Just to notice,...Last edited by BadCon; 01-26-2017, 10:37 AM. -
Re: New Members - please post your introductions here
I'm a young guy from Croatia. Electronics is my hobby since childhood.
I love making electronics projects (althrough last few years I was too busy to have time for it), repairing broken stuff and also building a PCs.
I found this forum before few years after my LCD broke and i fixed it. I also fixed several other LCDs for friends, few PSUs and even a motherboards, replacing a bad caps with new ones. Lately I've been fixing laptop mainboard and desktop GPUs reflowing them with industrial heat gun.Leave a comment:
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