Another great video looks a good bit of test equiptment too have
https://www.youtube.com/watch?v=0eixDdCpiO4
https://www.youtube.com/watch?v=0eixDdCpiO4
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Re: Short finder
Just need a voltage limited 1A CC PSU (LM317?) and you can read "ohms" (which would be milliohms) directly on your 200mV scale, if you have 20mV, even better.
Trick is not to have to send 1A through your circuit... could get toasty, but if it's a short, you probably don't really care anyway... -
Re: Short finder
I think you'd need the compliance voltage-limited to say 0.2V to not damage anything. That pretty much rules out the LM317, have to use an op-amp and power transistor.
I also do well with a good bench multimeter reading uV, using lower currents. You inject a current and can follow the voltage drop to the high current short. Or use a thermal imaging camera.Comment
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Re: Short finder
I have been waiting for this to become available, but I admit, I'm starting to lose faith.
https://www.eevblog.com/forum/testge...with-display)/Comment
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Re: Short finder
i already got the parts
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Re: Short finder
Looks like a similar idea to the Leakseeker 89, just with a display instead of a row of LEDs and sound.Comment
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Re: Short finder
All that is missing is a PCB layout? It's not that complicated, it's just people wanting changes and complaining etc. that takes away all the fun.
http://kripton2035.free.fr/Projects/shorty-display.htmlAttached FilesComment
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Re: Short finder
no, we need the revised scematic with the new current-sourceComment
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Re: Short finder
No need
The current source problem arises from using the 5V output line from the Arduino Nano.
As he wrote somewhere he couldn't figure out why the voltage (5V) dropped when the tips were connected. The LM1117IMPX-5.0 max. load current is 800mA.
While that might seem to be enough it's not: one must take in account the Arduino ICs, display, DAC, Op Amp and tips current source overall power consumption!
Therefore, replace that 5V line with a reliable 5V power supply.Comment
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Re: Short finder
Two things, the PCB layout is missing and kripton believes there's something wrong with the schematic.
So I think in the other thread people were discussing how to fix it. Also discussion of some features, true, but if you are doing a new layout, why not add some stuff if it's easy. Adding a regulator that supports battery use (not my thing, but I don't see a downside) and my personal one was upgrading the MCU. But I don't have pcb skills (yet) so I'd likely just take any board even with an arduino. But if someone with pcb design skills likes the idea of the rp2040 board, I can be point on the software...Comment
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Re: Short finder
rp2040 is overkill
whats wrong with the atmega328??
i wouldnt use the arduino though, just design the chip into the new board to save spaceComment
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Re: Short finder
Maybe, maybe not. More samples per second seemed to be desirable to krypton and others. With a nano costing 3 usd and an rp2040 board costing 4 usd I don't know why anyone would use an arduino anymore for a new design. There's also a wireless pi pico board that has been released, it's pin compatible and could be an interesting option, especially if they get bluetooth working.
Designing the chip into the board is going to increase the board complexity quite a bit, and probably increase the BOM because you are buying the components separate.Comment
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Re: Short finder
Mega328's are out of stock until summer 2023 due to the semi shortages. 328P Microchip "Not Recommended for New Designs" use the 328PB but Arduino.cc is screwing up not changing over to it. Strange the Microchip 328PB webpage says 64KB FLASH but datasheets say 32KB, fired off a website typo fix msg. Too bad they didn't really give it more memory.
RP2040 nobody is using it much, so lots around and $1 for the bare IC. I have not used it. For WiFi ESP8266 does great for me.Comment
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Re: Short finder
I have seen a lot of uptake of the rp2040 among hobbyists recently. I have been on the fence about it for a while, but there seems to be a lot of momentum. The lib support seems to be there, and they aren't in short supply like some of the stm32 chips.
Has the ESP8266 firmware matured? I messed around with a few some years ago and they seemed buggy and rough. They also don't have many pins.Comment
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Hi Folks
I'm looking for a extreme high current short killer solution for a reasonable cost.
I have an LGA1700 motherboard (ASUS PRIME Z790-P WiFi) where I exchanged the LGA socket already 3 times, and every time after the socket exchange I get a short of power supply lines VCORE (V variable) and VCCIN_AUX (1.8V).
After taking off the socket, the shorts dissappear again.
The soldermask on the socket is already partially demaged from the heat, so I have reconstructed the soldermask by manually painting the missing soldermask parts with a very small top of a...10-15-2024, 10:13 AM -
I check PPBUS_AON and there is a short present on the line, the computer shows a short when testing for short to ground, so when I inject voltage into the line, I get 0AMPS so no short is showing up. I have replaced a blown cap on this board that exploded and tested for the short and it is now removed. Any suggestions? I tested voltage at the line when the fuses are connected and I am getting 1.2 Volts at the line.
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Hello everyone,
I'm trying to repair my old Acer Nitro 5 (AN517-54-55T5). I've already bought a new laptop, so this is more of a learning project. For the experience, with no high expectations of success.
Well, my decice specs are the following:
Model: Acer Nitro 5 AN517-54-55T5
CPU: Intel Core i5-11400H
GPU: NVIDIA GeForce GTX 1650
Motherboard: GH51G LA-L181P Rev:1c
The symptom:
When pressing the power button, the power LED lights up for about 5 seconds and then turns off. Initially, the issue was intermittent: sometimes...05-26-2025, 10:49 AM -
Hi all,
Recently picked up this GTX1650 at a local flea market for a low price and wanted to use it on my secondary PC. I first tested the card and saw the fan spin for a split second and then nothing. Immediately I thought of a short circuit. Disassembled and found a shorted SMD capacitor, injected voltage into it (1V/4A) and two Mosfets got hot immediately (QN3103 & QN3107). Desoldered these Mosfets and the card turned back to life.
Bought replacements from Aliexpress and replaced them afterwards. Tried the card but still the saw the fan spin for a split second... -
Hi All, I have a 9th Gen Dell Optiplex micro PC motherboard which doesn't power on. When I connect the motherboard with power adapter, it goes into safe mode and turns off. So from info I have gathered online, it looks like there is a short circuit on the motherboard. So can you guys help me with figuring out the issue?
I am new to electronics repair, so my queries could be naive but I am ready to learn.
So I have a multimeter and a solder with me. But I can try to get a variable voltage power supply with a thermal camera as well. From what I seen online, best way is...
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