What was your easiest repair ever?

[CJay]

I observed that many times when everyone still had CRT TVs. If it won't power on at all, I'd hear "it's probably just the switch" which it never is, the one I'd hear a lot is "the picture tube is going out" which was never the case.

Then on sets that really did have a worn out CRT "it just needs an adjustment!"

'it's just the picture valve whats gone'
Solid state sets, you really don't want to have to replace the picture tube.

'the bloke down the road said it would be cheap and he knows cos he was in radar during the war'
Hasn't touched anything electronic since the war but still knows everything.

'I'd fix it myself only I don't have time'
Has been inside and twiddled everything, probably also replaced the fuse with a nail or aluminium foil.

[vk6zgo]

I've had too many to count over the years.  The general theme is that people usually suspect a major problem when it's something simple.  On the other hand, they usually say it's something simple when it does have a major problem....  I guess simple things like bad caps, or broken solder connections cause things to be completely dead and people assume the worst, but major problems like a bad acquisition board just cause a few errors in the self test.

I observed that many times when everyone still had CRT TVs. If it won't power on at all, I'd hear "it's probably just the switch" which it never is, the one I'd hear a lot is "the picture tube is going out" which was never the case.
Then on sets that really did have a worn out CRT "it just needs an adjustment!"

There is a reason behind the "just the switch" idea.
In many cases, the switch mode PSU loses its start circuit, but if you quickly switch it on & off, you can often get the rotten thing to start.
They keep doing this, until it doesn't work any more, in the meantime, they have wrecked the switch.
The TV set comes in as "faulty switch".

The first few times, in my innocence, I just replaced the switch.

As I worked at a TV Studio, I didn't really have the option of rejecting jobs.
We decided to "out source" some "domestic" TVs & concentrate upon Broadcast standard stuff.
This had mixed success, with some total disasters which had to be "fixed after the fixing" after they came back.

Even the good repair shops had their moments, though.
With one set, we did "first in"  checks, narrowed the fault down, attached a sheet with this information, & sent it off.
When we picked it up, it had their tag on it, which simply said "doesn't work"!

[petepdx]

Ditto on the 220V. Keithley current source. Slide switch clearly showed was in the 220V posistion

-pete

[maggo]

My easiest fix is a draw between an AKAI AM-75 Digital Integrated Amplifier and an ELAC Subwoofer

AKAI:
I got it very cheap from my neighbour because it did not work properly. After turning it on, it constantly went off and back on again.
Found a broken solder joint on the main PCB. Easy to see with the naked eye.
Resoldered and that was it.
After a little while I also changed the relays for the speaker outputs.

ELAC:
Same thing here. Faulty solder joint. Fixed and good as new.
To be honest I fixed several more solder joints. Some were looking very suspicious...

But yeah. Almost zero effort for two pieces of high quality audio gear. 

[HalFET]

Biggest ratio was on a Keithley 130 multimeter, someone had tried to power it up with a power supply but switched the leads. Took the whole of 5 cents to replace the protection diode.

[soubitos]

Customer arrives in shop in panic... brings in a pc with just released Pentium 4 3Ghz Pres-hot Intel Inside, NVidia graphics again top notch, raptor HDDs not the SSD bulshit etc, a 1500-2000 euro machine maybe more with the "extras"...
Save me, my computer won't boot, its says, insert system disk on a black screen (or something like that)......

Ok.... you are good to go.....

Customer offers to pay, i charge him nothing leaves happy but embarrassed....

Oh, the old FDD days.... leave one inside and you might... not boot ever again!~LOL

[neo]

Well it was hard to figure out but was an exceedingly simple fix. The cord was part of the multi meter and had gone open intermittently, and the HV capacitor inside it, for the nixie tubes, vaporized when i touched it.

[onre]

Old thread, but had to brag:

A couple of weeks ago I "fixed" two oscilloscopes in a single day. One required locating and turning up the separate "analog brightness" knob to get the analog side tracing again, another needed a firm press of "INT/EXT" switch to get internal triggering "working" again. 

[stefan_o]

My easiest repair ever was a Sennheiser SKM 5000 professional wireless microphone several years ago (there were about 500€ used in good condition back then). Bought it as defect with weird rumbling noise for about 100€. Opened it, directly spotted a broken solder joint at a big SMD tantalum capacitor, fixed it, put it back together, works perfect. Repair took less than 10 minutes 

For the computer builders here: did you ever have the experience that your friend's computer went dead, they couldn't fix it, and the computer magically fixes itself after you show up?

Yes! I think one of the main reasons was overheating, these old towers/desktops could suck in massive amounts of dust into the heatsinks that eventually even blocked the fan. So my initial response to the question "what tools do you need to fix that" after a pc "died" was: most likely just a vacuum cleaner.

[onre]

Alesis Quadraverb multi-effect device from dumpster: opened it up and reattached the display ribbon cable.

[edpalmer42]

Easiest possible repair - I didn't do anything!

A friend had a dead big screen plasma TV.  He said that it quit working some months ago and asked if I would inspect the board if he removed it from the TV.  I said sure.  Later he told me that when he went to remove the board, he found that some of the mounting screws were loose, so he tightened them.  Problem fixed!

Should I send him an invoice for the repair?  Without me, it never would have happened!   

Ed

[Teledog]

Reprogramming an Icom HT radio that was programmed out of band (it was flashing red/blue)
Maybe 2 minutes?

[coromonadalix]

bought an electronic voice synthetised chess game for 5$,  put an 25 cents transistor because the voice was not good, made an 600$ profit on ebay it was a rare item to my total stupefaction  

[bitseeker]

Wow, easy repair plus major score.

[ScottM]

By far the easiest and also biggest sigh of relief...

On call tech for the weekend. Usually nothing happens. Maybe a call for resetting something, 10 minutes on phone is typical.

Phone rings. Customer is bonkers. " system is dead, you need to come right away!"

Me:"are you sure it has power?" (Client is known to use breaker as switches)
"Oh, yes it is clearly marked - do not turn off"
"Ok I can come but it is the weekend and I'm 3 hours out. We bill travel time and I need to go to the shop and get some parts."
"Please come guickly"
So since the system is total garbage I go to the shop and grab several boxes marked 'kludge'. Drive 3 hours cursing all the way at my bad luck for getting this call. It can never be fixed. Arrive in bad mood. Yup system is dead. Plug meter to mains (you know the reading right?)
Reach over turn on breaker as the panel is just arms length away.

Client: "So there is no charge because you didn't fix anything?"

It sure was a sweet 3 hour - billable - ride home.

[precaud]

Not necessarily the "easiest" but pretty easy. I've had a Lecroy 9450A DSO sitting around waiting to be diagnosed for 6 or 7 years. I got it cheap back then because it powers up to a blank screen and no activity. It has a very visible gash/deep scrape on the front bezel from some careless handling, so resale value would have been compromised, which lessened my motivation to fix it. On the other hand, it has the WP01 math and WP02 FFT options installed, which (as I later learned) turn it into a quite capable 300MHz spectrum/network analyzer.

So a couple weeks ago I opened it up for another look. Power supplies checked out good. No sampling clock signals. I pulled the cpu card out and saw that the Eurocard connector "fingers" were half clogged by dust bunnies! That can't be good. Easy to see why - the cooling fan blows right into the channel and cpu cards (with no air filter!), the Eurocard connectors are situated right there too. I checked the nvram backup battery on the board and it was dead. So I cleaned the entire board and put in a good 3V lithium battery. Pulled the rest of the cards and they were similarly dirty with dust-clogged connectors. Put it back together, turned it on, and there were signs of life - the crt and some front panel lights blinked momentarily. That means the display probably works, and the cpu was trying to boot it.

While poking around, I remembered seeing a Reset button on the bottom of the rear panel. I pushed it. Nada. Nothing happened.

Next day, while reading through the service manual for more troubleshooting clues, I happened on a paragraph that described the reset button. It warned that the nvram contents are initialized by a reset. Sounds good to me. And you can't just push it - you have to hold it in for a few seconds until you hear a beep, which signals that then the cpu has reset everything and then reboots. So I tried it and -voila - the 9450A came to life and has worked fine ever since! Some bad constants in the nvram were causing it to hang. The crt is excellent with no visible burn-through, so there's plenty of life left in it. I really like these Lecroy scopes and have decided to make a place for it on my bench.

If only all repairs were this easy.

One drawback to the some of the 9400-series is that they put the power switch in the back panel. (Huh? What were they thinking?) That means I can't put it on (or under) a shelf among other equipment. It's gonna take some bench reorganizing to make a place for it that allows me to reach the switch.

[ddwilson]

when I worked at a hardware store someone returned a multi-meter after it got claimed as defective I took it home and installed a battery package even said battery not included.
 

[SeanB]

Inverter welder from the local Makro, bought as "shop soiled", and also rattled. Got an even better price from them ( bought 2 for half the price of one), and as it was demo stock I only got a single set of leads. No problem, tried both and fixed the rattle, EMI choke on some sense wires had broken in half, and i did not bother to replace it, too much PT to get a replacement one from a CFL lamp to slip on the loom there.

So, took the one with leads, gave it away, and later on got a pair of those 9.5mm twist plugs and used them on a set of spare welder leads from an old oil filled welder I had, and now have better leads than the unit came with originally. First job with it was repairing washing line poles, as they needed to have some braces installed to keep them upright. then a little testing and I am slowly learning how to weld thin sheet plate with it, the HF start really makes it easy to weld at low current and not burn through the plate too much.

[Bud]

Not exactly repair since it did not touch my hands but still rather funny. While browsing eBay I came across a HP frequency counter that the seller was advertising as Not Working, for parts. When switched on, the device displayed "NO OSC" and did not do anything. I happened to have exactly same counter model and I knew you get this message if you switch the device to use external 10MHz reference clock before you connect the external clock source. The message means No Oscillator, which makes sence. There was a photo of the back of the device that the seller provided, i checked the photo and sure enough the clock switch was in "External" position.    So the "fix" for it would be to flip the switch back to Internal clock.
I did not bother contacting the seller. I did not need a second counter and some other buyer might have made a good deal.

[envisionelec]

Behringer iNuke 3000DSP. The rack in which it was installed took a lighting hit to GND. Insurance already covered the replacement...

A single ESD1 diode was shorted across the output FETs. Replacing that restored full operation. I am still surprised the damage was so minimal!

[CJay]

I am still surprised the damage was so minimal!

Lightning can be very strange, when I repaired televisions for a living we got a call to go and look at a few houses on one street where there had been a lightning strike.

We could tell which house had been hit because there was a sooty trail down the wall where the antenna downlead had been along with a flashover tinge on the brickwork, we reckon it was vaporised copper.

In the garden there were thousands of tiny beads of aluminium, that was the TV antenna from the roof.

The only damage inside the house was TV itself which worked perfectly after we resoldered the few inches of coax from the Belling Lee socket back onto the socket and the tuner.

The neighbour's house, every appliance in the place was destroyed yet there was no visible sign at all of damage, several other houses had similar but less extensive failures.

[peteb2]

Had a slide-decker truck arrive at my home one morning completely out of the blue... It had a car on the back and its owner traveling in the truck cab with the truckdriver. She lived not far from me (i'd met her a few times at local friends BBQs and parties and once had a chat with her etc)

Story goes that her car had refused to start for the last 3days (in the morning) and so she left it and took the bus. For some reason she chose to get her car delivered to a garage on the 4th morning of the drama but as she traveled in the truck with the poor driver she had a massive brain-fart and decided they had to drop in on the way and see me, because she suddenly remembered i like "playing around on old cars and those coloured wires" and everyone had told her it must be an electronic fault. ....

I was about to leave for my work too but humored her as the truck driver basically rolled his eyes... I had a look at things, climbed up on the deck of the truck and clambered into the car, pushed the keys into the ignition and turned them. The dash cam up but it just would NOT crank the engine over... By natural process when you've done something a million times, and the car having an automatic transmission i selected P and because the shifter was sitting in D. The engine fired and ran the instant it cranked... 

I was stunned that the towey had probably not checked the fault and simply put it up on his truck and i was doubly stunned she'd not bothered to do a work-through as in a basic procedure should your car not start.

Anyway i left her to sort out the cost of her car being loaded and carried a couple kms to my home and the callout fee.... The towey unloaded her car and she headed off to her work. Haven't talked to her since and it was over 10yrs ago!

[scopeman]

Let's see:

Somewhere I have pictures of all of this stuff but I'll be darned if I can find it.

Wavetek 39 - $25.00 eBay. Powers on but display blank. Popped the cover on it and the resistor for the reset circuit (through hole) had one lead touching the pad. Cleared the pad and soldered the resistor in place and of course it worked like a charm!

Fluke frequency 512MHz counter - won't count. $12.50 eBay. Cleaned internal/external time base switch. Perfect!

LeCroy 224 Waverunner. $110.00 eBay. Powers up no display. Bad 3 terminal regulator in power supply. Plus the unit must have been used in a coal mine!

Fluke 8060A $27.50 eBay. Clean-up and replaced caps. Still dead on cal after all these years.

General Radio 1656 Bridge. $159.00 Sold as perfectly working (is in mint condition - looks like never used). One range would not null. Found a pass through wire on the range switch was never soldered at the factory. It appears that the range was never used. Soldered and perfect!

HP8753C/8702A Network analyzer. After cal if you zoomed in on the smith chart the calibration point would move around. Turns out that in the 85046A S parameter test set there is a clamping set screw that locks the leftmost connector ground to the mounting point. Tightened the setscrew and the problems go away. Cal good to the noise level of the unit.

Tek 475A - IBM branded scope with probes and cart. Really clean but dead. Bought for $30.00 at a local hamfest. Had a blown (shorted) bridge on the 8V power supply. Amazingly enough the caps were good. Soldered in a new bridge. Fan a little noisy but works perfectly.

Tek 422 - AC powered model. Older style with nuvistors. Really clean but no trace. Shorted cap in the HV power supply. Replaced Cap. This is my loaner scope when someone needs to borrow a scope.

Tek 2220 bought for $20.00 at a hamfest, untested but owner claimed no sweep. Got it home on the bench, powered it on and set the trigger from Norm to Auto scope sweeps. Not a thing wrong with it. Great scope for audio work.

HP3310B Function Generator. Pulled from a scrap pile of instruments from a place I worked at years ago. No output on any setting. Rotating the phase control on and off the Free Run position causes the generator output to "burp". Cleaned the control contacts for the Phase/Free Run control restores normal operation.

Tek 453A - Given to me by a friend that no longer wanted it. Claimed that the Delayed sweep function did not work properly. Sweep Length control in the wrong position.

I could probably list dozens more. Sometimes fixing things is more fun than using them!

Sam
W3OHM

[Twoflower]

20 years or so ago. Friend of mine got for a beer a 6-CD changer for a car. The original owner said it jumped all time. Nevertheless my friend asked me to install it in his car. While doing so I asked my friend if he knows which orientation it was mounted originally. And yes the damping setup was wrong (horizontal vs. vertical mounting). Full success.

But the damn thing paid back later. A couple months later said friend showed up telling me the changer ate a CD and reported an error code. So opening the changer and moving the gear-work mm by mm to even slower moving the CD out of the drive. After 30 minutes fiddling on the gears the CD was finally out. While closing the thing I noticed a label in the inside of the lid. It was the instruction how to eject the CD if the same error code is reported: Just slide a plastic card in and the CD will be spit out 

[anachrocomputer]

Saw an HP 3325A synthesiser function generator the other day for £150, sold as non-working. Too much, I thought, and waited. The seller dropped the price to £100 and then I began to consider it. "Will not power up". Hmm... Power supply fault? Check photos, and eventually realise that it's set to 120V, and the seller was testing it in the UK (240V). OK, so maybe the mains transformer is burned out? And the seller knows this and that's why it's for sale? Or they don't know that and it's a simple fault but they don't do repairs?

Well, I couldn't resist giving it a go, and when it arrived, sure enough, it's set for 120V. And the fuse is blown. One new half-Amp fuse, and a couple of switch settings inside, and it works! Tested as far as I can with the scope and even plugged in an HP-IB interface to try that out. All OK!

Winner winner, chicken dinner!