The community repair thread

west · October 2020

Danny1969 said:

west said:

That dannys a talented fellow .... This is small potatoes but , i had a panasonic dvd-r recorder that had served quite well about 5 years and then it died , i felt it should have lasted longer so after doing some digging online i found a reference that pannasonic had admitted they used the wrong component on the power supply and the gave the correct value .
off to ebay and bought the cheap as chips resistor ( i think ) i took it apart and removed the ps board popped round to my mates as i didnt trust myself to disturb other componants on small tracks and bobs your aunties tranvestite lover .... its a bingo .. ive also repaired an LG 32 tv this way too ... its worth a go even with limited knowledge ... !

Nice work !
The fault that I see the most in things like that is the power supply won't turn on because the capacitors have failed. This is an inherent and common fault in any switch mode design. Often you can see the caps have failed because the tops will be bulging upwards rather than flat. This power supply is in an expensive Apogee audio interface, you can see the caps bulging, this is eventually what happens to an Electrolytic capacitor in a switch mode power supply. If the supply is well designed .. which this one is then turning on the unit will produce a light that will blink and go off as the PSU detects the abnormal load caused by the bad caps. If you see this on a TV or DVD recorder etc start by looking at the caps.

The rest of the power supply will generally be OK so as you say, it's worth doing.

Yes ! it was a bulging cap on the LG tv PS ...

Kittyfrisk · October 2020

Important not to get confused with a Bulgin Cap

https://uk.rs-online.com/web/p/circular-connector-dust-caps/5044588/

digitalscream · October 2020

Excellent work, @Danny1969 - although I'm somewhat surprised that you didn't take the opportunity to swap to a USB C charging port on the G10

Danny1969 · October 2020

digitalscream said:

Excellent work, @Danny1969 - although I'm somewhat surprised that you didn't take the opportunity to swap to a USB C charging port on the G10

USB C is a more robust port but it's 24 pin and massively complicated requiring a handshake to decide on how many volts and amps to begin charging ... I don't understand how half of it works to be honest

digitalscream · October 2020

Danny1969 said:

digitalscream said:

Excellent work, @Danny1969 - although I'm somewhat surprised that you didn't take the opportunity to swap to a USB C charging port on the G10

USB C is a more robust port but it's 24 pin and massively complicated requiring a handshake to decide on how many volts and amps to begin charging ... I don't understand how half of it works to be honest

In that case, I fully understand your reasoning

Kittyfrisk · October 2020

In the spirit of the thread, the link below is an absolutely fabulous place for cool stuff about EVERYTHING, particularly manuals for repairing things. Who doesn't love a good eclectic resource? Enjoy

https://archive.org/details/manuals

Danny1969 · October 2020

So here's one of todays challenges, it's an Asus Zenbook which is a tablet PC running Win 10 with a magnetic clip in keyboard. This is in bad condition, the screen is cracked all over and the micro USB port used for charging has been pulled on the board. The cost of a new screen and repairing the board makes it BER but the customer wants the data. How do you get the data of a tablet which you can't turn on. Now normally I would remove the shattered digitizier and LCD to get at the board, fit a new socket and than a new screen but they won't pay for that .. they just want the data. i can't tether it to a PC, the usb port is gone.
Now if you find yourself in a similar position and these micro USB ported tablets always break here's what I did which was quick and easy
I cut a hole directly above the micro USB port. With that out of the way I attached 2 wires, one for 5V and one for ground. If your not sure which one is ground buzz the end track that's shorted to the chassis pad, that's ground and any connection to that will do. The pad the other other side on the end is 5V. Then cut a micro USB cable in half and identify 5V and ground. One this cable it's red and black but never trust the colours, always measure.

Image: http://www.thesuperheroesonline.co.uk/asus11.jpeg

Now that alone will generally very slowly charge at around 400mA as the charger can't identify the device and what current to put out as there's no connection to the data pins and their tie resistors. So fooling the charger with some external resistors to bias the D1 and D2 will allow more charge. So this doesn't look pretty but it's up and running and I'm copying their data to the SD card in the slot. Job done, very much billable for me and very simple.

Image: http://www.thesuperheroesonline.co.uk/asus22.jpeg

Chris.B · October 2020

Excellent ingenuity and dexterity Danny- impressive surgery on the broken Asus

vasselmeyer · October 2020

Love threads like this. For those of you that do repairs like this, any ideas for suppliers of decent laptop batteries that won't catch fire? My Dad's HP laptop needs a new one, part no, 816238-850. Can't seem to get a genuine one from HP. There's one on Amazon for £105 but I'm not sure it isn't counterfeit. The items of third party replacements on Amazon range from £40 to £75, but I don't know any of them and I'm fairy paranoid about random cheapo stuff. I don't want to be responsible for his house burning down.

boogieman · October 2020

I recently bought a Dr Battery replacement from Amazon for my HP Envy laptop. It’s been working fine, gets plenty of decent reviews too.

Danny1969 · October 2020

The trouble with batteries is you don't know what they have left out until it's too late. With a hard shell external battery there's more latitude for failure without doing damage. With an internal soft shell battery like some Envy's, Macbook Pro etc failure can be more of a problem with puffing up pushing against palmrest ets, With no shell soft batteries like ipads and phones failure can easily cause a fire
Amazon and Ebay are awash with fakes and cheap Chinese copies, I tend to either buy the genuine article in used condition or buy a good after market model like the LL Power range from PSA parts

PolarityMan · October 2020

tried repairing the bass drum pad for my e-kit today...no joy

Havent taken it apart again to see if i've knocked the wiresloose again after resoldering or what but it wouldnt surprise me as i am shite at soldering.

Danny1969 · October 2020

So little favour for a friend today who brought a 9V adapter for his pedal and surprise it doesn't work as like 99% of these things it's centre pin is wired positive.
So here's a quick hack to change that around while keeping things neat.

Cut the wire so both positives are long and both negatives are short. Cut a piece of heatshrink and to make things easier make 2 lumps of bluetack.

Image: http://thesuperheroesonline.co.uk/b2.jpeg

Slide the heatshrink over one end length of wire first, then position wires on bluetack .... the fact you cut both positive wires long on each bit of cable now means the polarity will be swapped over when you join them.

A neat joint is a piece of cake when sat on the bluetack

Then slide your heatshrink over the joint and then you have a Boss type adapter 9V centre neg with no big joined lump in the cable and no chance of the wires shorting out because their joins are spaced apart.

drofluf · October 2020

Was wondering why you’d cut the wires to different lengths! Very sensible idea that I’ll steal when I do something similar.

sev112 · October 2020

Anyone got any suggestions for shortening full height ready made eyelet loungecurtains ...?

Kittyfrisk · October 2020

sev112 said:

Anyone got any suggestions for shortening full height ready made eyelet loungecurtains ...?

Find someone with a tape measure & a sewing machine.

sev112 · October 2020

Kittyfrisk said:

sev112 said:

Anyone got any suggestions for shortening full height ready made eyelet loungecurtains ...?

Find someone with a tape measure & a sewing machine.

I’m not so sure about the sewing machine, it’s a bit more complex than that .............

underdog · October 2020

sev112 said:

Kittyfrisk said:

sev112 said:

Anyone got any suggestions for shortening full height ready made eyelet loungecurtains ...?

Find someone with a tape measure & a sewing machine.

I’m not so sure about the sewing machine, it’s a bit more complex than that .............

Why? You remove material from the bottom, so the eyes won't matter.

boogieman · October 2020

underdog said:

sev112 said:

Kittyfrisk said:

sev112 said:

Anyone got any suggestions for shortening full height ready made eyelet loungecurtains ...?

Find someone with a tape measure & a sewing machine.

I’m not so sure about the sewing machine, it’s a bit more complex than that .............

Why? You remove material from the bottom, so the eyes won't matter.

I can’t see why it would be difficult either. Cut them to length allowing enough material for the new seam, sew them back up again. A sewing machine would make the job a hell of a lot easier but I suppose they could be done by hand if you have the patience. My wife’s done this to a couple of sets of curtains at our place and it’s not like she’s a trained seamstress.

Failing that a lot of dry cleaning places will do alterations.

Danny1969 · October 2020

So here's a great little cheap tool to help diagnose whether the problem of a typical tablet being dead is the charging port or the battery or both. This cost about £4 and can save you so much time. Plug in inline to the USB charger and it will give you the voltage and the current being drawn. So before you plug the cable into the tablet you should have 5V and 0 amps being drawn.

Image: http://thesuperheroesonline.co.uk/f1.jpeg

Now plug the tablet in and see what you have, generally you will see a charge current of between 0.5A and 2.5A depending on the type of tablet and the type of USB charger. If you get no charge current then check the socket, this customer has loosened the socket by constantly wiggling it trying to get it to charge so that was first thing I fixed

Now watch the charge current. Once the chip on the tablet has decided to charge the battery it will modulate the current depending on what the battery management tells it. So now it's trying to charge at 500mA

Unfortunately for this customer the battery needs replacing as well. After trying to charge for around 15 mins the current dropped to 40mA because the battery is shafted. So in general no current pull = socket bad and these micro USB's do generally fail .... and 500mA start charge current falling to virtually nothing means battery is duff.

So for £4 it's quite a bargain tool to help work out what's wrong. I doubt it's calibrated to a high standard but it doesn't need to be to show you what's happening charge wise.

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