TX-Cloner433 burned part recognition  - Page 1
Forum section: electronics / repair

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 22, 2022, 10:30:59 am
content: This is from a garage remote control Superior TX-Cloner433.The white part marked with red is burned and is not recognizable if it is a resistor or a capacitor or its value.Can someone help to recognize this part? It is connected in parallel with the resonator and the capacitor. This part has continuity as it is.Regards,

author: cnqhdszq
author_rank: Regular Contributor
timestamp: May 22, 2022, 12:13:12 pm
content: Why do you think the white part is burned ?I think the part is OK.The battery is 3V ,and the battery resistance is too large , so the battery can not output high current to burn it .If you have a LCR bridge ,you can check the part .

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 22, 2022, 01:25:33 pm
content: Quote from: cnqhdszq on May 22, 2022, 12:13:12 pm1) there were a smell of burned part 2) the part was moved from its position which means the solder under it was melt 3) it has continuity ~1.4 ohmPs: the battery is 3+3v=6v

author: wraper
author_rank: Unknown
timestamp: May 22, 2022, 01:50:20 pm
content: To me it rather seems corroded and mechanically displaced. Seems to be an inductor connected to the circuit with SAW resonator.

author: bdunham7
author_rank: Super Contributor
timestamp: May 22, 2022, 01:53:23 pm
content: It looks like an abused inductor. If it has continuity, it probably isn't bad. As for what happened to it, is that green discoloration corrosion or something else? I would start by cleaning it and carefully soldering it back on.

author: fzabkar
author_rank: Super Contributor
timestamp: May 22, 2022, 04:42:46 pm
content: Is there an FCC ID on the label? Sometimes the FCC web site has schematics.

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 22, 2022, 05:28:27 pm
content: Quote from: bdunham7 on May 22, 2022, 01:53:23 pmThe green discoloration I think it's from the pcb itself.Yes, I thought of resoldering back on, but how can I know if it is an inductor or anything else (maybe the LRC circuit is the answer for that )? There are no signs of it's kind. Does inductors have white colors? O don't know.And the big question is why and how it is moved on? Why it smells like a burned part?

author: bdunham7
author_rank: Super Contributor
timestamp: May 22, 2022, 05:36:06 pm
content: Quote from: sdancer75 on May 22, 2022, 05:28:27 pmParts that small may not have markings. Yes, it looks like an inductor might. To really know for sure you'd need an LCR meter. I'm not sure how you can localize a burned smell to that small of a part, unless you are a mouse or something. As for how it moved, the possibilities are 1) it got hot due to a malfunction elsewhere in the circuit 2) it was originally installed poorly or 3) it has been physically hit or pushed.

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 22, 2022, 05:36:25 pm
content: Quote from: fzabkar on May 22, 2022, 04:42:46 pmI didn't find anything...It only saysEspanaManufactured by FAB : B06450563

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 22, 2022, 05:44:15 pm
content: Quote from: bdunham7 on May 22, 2022, 05:36:06 pmThanksNo, of course I am not a mouse 😁 and surely I don't have super natural sensations, but under the microscope it was the only part that it had a visual damage and from my perception the smell was from that specific part. Anyway maybe I am wrong but I will give it a try by resoldering that part.I don't have LCR meter so I will guide almost blindly....

author: fzabkar
author_rank: Super Contributor
timestamp: May 22, 2022, 06:05:15 pm
content: Is the 28-pin IC a standard part? If so, then its datasheet may have an application circuit.

author: gamalot
author_rank: Super Contributor
timestamp: May 22, 2022, 06:14:02 pm
content: It's probably an inductor when it's next to what appears to be a SAW resonator.The components in SOT23 package with R25 mark on top should be high frequency transistor 2SC3356.The transistor with G1 on top should be MMBT5551LT1G and the one with M6 on top should be S9015.The one in SOD323 package in the lower left conner of the picture could be a BB148 variable capacitance diode.

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 23, 2022, 05:34:59 am
content: Quote from: fzabkar on May 22, 2022, 06:05:15 pmYes, it is the 28-pin version ie PIC17F723A, I will take a look inside the datasheet!! Thanks

author: sdancer75
author_rank: Frequent Contributor
timestamp: May 23, 2022, 05:39:06 am
content: Quote from: gamalot on May 22, 2022, 06:14:02 pmProbably you and the others have right. I will try to resolder the part and try again.

author: sdancer75
author_rank: Frequent Contributor
timestamp: June 29, 2022, 01:51:37 pm
content: For your interest, the problem solved. It was indeed the smd white inductor. I re-soldered it on the pcb and it worked like a charm.Thanks to all