ezenia
Member
Last Activity: Yesterday, 08:38 PM
Joined: 06-12-2020
Location: Hounslow
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Replacing YT5202A fixed the problem. Bulb now works fine (will now see how long it stays working). So YT5202A must've been some LED driver that somehow failed.... -
LUMIMAN Smart Bulb IC ID?
Hi,
I have a LUMIMAN Smart Bulb that suddenly stopped lighting one day. The bulb is still detected in the app, but won't light. I've probed around and nothing seems to look off with any of the diodes, caps or resistors. The Bluetooth/Wi-Fi module seems to be working as it's still detected in the app. I even tried deleting and re-pairing the bulb (it didn't light, but I was still able to follow the pairing instructions), it re-paired fine, but still no light.
In diode mode, the LEDs all light up when probed so I'm guessing this means the LEDs themselves are OK. I was expecting... -
Alba CBB16 replacement switches
Hello,
I've been given an Alba CBB16 radio to look at. The issue was no sound from either speakers when switching to the radio. They'd just be some buzzing/static. I did some troubleshooting and found that if I mess with the switch in certain ways, the sound cuts in and out on the right channel speaker. It'll go from quiet with some static/buzzing to really loud and clear depending on how the switch is moved. This told me that the radio at least has an issue with this switch.
The switch appears to be broken on the inside causing a poor connection. I tried cleaning it... -
So I've been trying to figure out what is wrong with the board and so far this is what I've found (not sure if some of these are considered issues):[LIST][*]DM804 and DZM805 appear to be bad - diode mode shows OL in both directions even when out of circuit.[*]DZM806 may be bad as well - I get OL in one direction (red probe on lone pin) and then 2.2V on one of the pins and then OL on the other (black probe on the lone pin). I got these readings both in-circuit and out of circuit.[*]QM802 is shorted on all 3 pins. Guessing this is what took out the diodes. QM801 doesn't appear to be shorted.[*]TM802...
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Re: Samsung LE32A456C2D TV no power
Is it normal for RM812 and RM814 (47Kohm resistors) to be measuring 10.9ohms in circuit? Just wondering if that's normal behaviour or if that signifies an issue somewhere. I tested both of them out of circuit and they read 47Kohm.
EDIT: looks like TM802 was the cause. I desoldered that and now RM812 and RM814 show 47Kohms in circuit.Last edited by ezenia; 11-18-2023, 08:51 PM.Leave a comment:
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Re: Samsung LE32A456C2D TV no power
So far I've removed the glue from most of the components. There's just one more that has glue touching the capacitor legs. I'll remove that one later on.
I decided to take out the QM802 component as I was getting continuity on all 3 pins while it was in circuit. When out of the circuit, the same thing happens. So it looks like QM802 is bad?
The two jumper wires next to the blown blue cap still have continuity across both pins. Does this mean they're still good and don't need replacing (just cleaning)?Leave a comment:
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Re: Samsung LE32A456C2D TV no power
More to do than I wanted/expected, but I'm going to try working on it when I can. It'll be good free practice even if I don't get it working.
For removing the glue, what is used? It seems too hard to just scrape off with something like a flathead screwdriver.
The fuse next to the power connector, marked T6.3AH 250V on the board, is blown.
I'm not too sure about the light bulb test. I probably won't attempt that as I don't know exactly where or how to safely connect the bulb to the circuit. I've briefly...Leave a comment:
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Re: Samsung LE32A456C2D TV no power
I've also attached a photo of the burn mark on the TV's chassis. Is this mark indicative of damage done to the TV itself, or is it there because of the blown components on the power supply board?...Leave a comment:
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Re: Samsung LE32A456C2D TV no power
I've attached a pic showing the front and back of the power supply board in full. Hopefully the quality is OK. If not, I can try to take some more.
I took off the blue cap, but unfortunately this resulted in the other pad coming off. So now the back of the board where the blue cap should be soldered to has both of its pads missing. This can be seen in the pic I attached. The burn marks that were previously on the back of the board are mostly gone as I used isopropyl alcohol to try and get rid of it.
I put my multi-meter...Leave a comment:
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Samsung LE32A456C2D TV no power
Hello,
I found a dumped Samsung TV. I decided to take it to see what might be wrong with it.
The TV is lifeless. There's no standby light or anything.
I opened it up to see if there's any clues as to what might be wrong. I took out the power supply board first and immediately noticed a visible burn mark on the TV's metal casing.
It appears a small blue capacitor that sits right next to the massive high voltage capacitor has blown. There's visible burn marks on both the front and back of the power supply board. I took 2 pictures of this which...Last edited by ezenia; 11-09-2023, 08:03 PM. -
Re: PS4 controller left stick potentiometer replacement issue
Found a potential seller. I asked them to take a picture of the inside of the potentiometer and they took a pic. I attached an image.
Will these ones work better?...Leave a comment:
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Re: PS4 controller left stick potentiometer replacement issue
Thought so. Any idea where to get ones like that from? I don't want to order random ones and get ones that don't work properly. A lot of listings on eBay/Aliexpress don't show what the inside of the potentiometer looks like.Leave a comment:
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PS4 controller left stick potentiometer replacement issue
Hello,
Not sure if this is the correct section, but I have a PS4 controller that I am trying to fix. It developed stick drift on the left stick and the usual simpler methods did not fix the problem.
So I went on eBay and ordered some replacement potentiometers. [URL="https://www.ebay.co.uk/itm/174967976757"]https://www.ebay.co.uk/itm/174967976757[/URL] is where I got them from.
I took the green potentiometers off the replacement sticks and soldered them onto the PCB. Assembled the controller and ran some tests. The drifting was somewhat fixed... -
Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
Found a cheap U1 chip on eBay. Replaced it and unfortunately the fan still behaves the same.
The LEDs are now behaving differently. When the fan is off and cable plugged in, I get the usual red faint rapid flicker LED and solid green LED. When I press the fan switch to turn on the fan, the red LED goes solid bright and the green LED goes off. This is with the motor disconnected.
Once I re-connect the motor, I get some different behaviour. With the fan off and USB cable plugged in, it's the same red...Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
Another thing:
With the USB cable plugged in and the fan off, if I try to measure voltage on U2 on either pins that lead to the button switches, the red LED goes solid red and the voltage does drop slightly.
If I measure the battery voltage in another area (say at the battery connector or R7), I get a reading of 4.2V (it's not steady though, it keeps going from 4.2v to nearly 4.3V and then down again).
Once I try to measure the voltage at the aforementioned U2 pins, the voltage drops ever...Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
Ah yes, looks like it is. The voltage at pin 3 (labelled BAT on datasheet) is present on the battery connector.
Any idea what the STDBY pin is meant for? When the USB cable is plugged into the port and the fan is off, I am not getting a stable voltage reading on this pin. Once I turn the fan on, the voltage on this pin goes to 2.2V. Is this normal behaviour?
Should the battery voltage also be present at the fan switch button? Since this fan doesn't use a battery, shouldn't the voltage here match the...Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
This fan isn't using a battery. One of the connectors is unused. I remember one of them was empty. I checked with the Google translate app and it says the connector near D1 is "Battery". I wouldn't think they'd add a charging circuit to a board that is not making use of the battery connector.Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
The other connectors are for the water mist spray feature. I don't use that part of the fan. I've only ever used the fan itself which is the middle connector.
I am pretty sure the fan feels quieter as well. I remember this fan being quite noisy even on the first speed setting. Now it seems like it's quieter, perhaps it's running slower than normal.
I currently suspect something might be wrong with U1. The behaviour of the red LED is bothering me as well. I don't think it should come on when the fan...Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
Do these voltages at U1 look normal?
This is with the cable plugged in and the fan being off:
Pin 1: 3.3V
Pin 2: GND
Pin 3: Around 4.2V
Pin 4: 4.74V
Pin 5: Can't get a stable reading, it's jumping between 015.0-070.0mV
Pin 6: 0V
With the fan turned on (first speed setting):
Pin 1: 0.670V
Pin 2: GND
Pin 3: 4.08V
Pin 4: 4.73V
Pin 5: 2.178V
Pin 6:...Last edited by ezenia; 06-24-2023, 09:33 PM.Leave a comment:
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Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4
I checked for shorts, but couldn't identify any....Leave a comment:
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