What was your easiest repair ever?

[texaspyro]

Got an HP 5216A frequency counter from the 'bay a few months back.  Not counting, self test unresponsive, displaying all zeroes.  Discovered that the 'frequency standard' switch on the back panel was set to 'external', so it wasn't seeing the built in oscillator.  Flipped the switch to 'internal', and it's now operational.

I've picked up several HP5370 counters for dirt cheap because of that.  The processor is clocked by the frequency reference.  No ref -> dead counter.

A friend of mine bought a bad Tek 475 scope at a liquidation auction.  He missed the fine print in the auction listing that mentioned it was a pallet sized lot of dead scopes.   The problem... they were all set for 220V.  All were good.   I tested and calibrated all of them and received a 50% cut of the loot.

I wound up with a palette of Pace PRC-2000 solder stations because an auction failed to mention it was a large lot.  When I went to pick up the solder station, a big burly guy showed up pushing a palette jack with a huge pile of the beasts stacked on it.  I had to make a couple of extra trips to schlep them all home. (BTW, new they sell for around $6000 each with all the accessories).

[bitseeker]

Could this even be considered a repair?  Or simply a bit of maintenance.

One man's maintenance is another's repair. Unfortunately, too often even these levels of intervention are generally treated as catastrophic failures destined for the bin. So sad.

[Berni]

A good example was the photocopier that Dave found in his dumpster room.

He had a peek inside and found a paper jam. Once the rebellious piece of paper was removed the photocopier worked just fine and still had plenty toner left in it.

[CJay]

I've picked up several HP5370 counters for dirt cheap because of that.  The processor is clocked by the frequency reference.  No ref -> dead counter.

A friend of mine bought a bad Tek 475 scope at a liquidation auction.  He missed the fine print in the auction listing that mentioned it was a pallet sized lot of dead scopes.   The problem... they were all set for 220V.  All were good.   I tested and calibrated all of them and received a 50% cut of the loot.

I wound up with a palette of Pace PRC-2000 solder stations because an auction failed to mention it was a large lot.  When I went to pick up the solder station, a big burly guy showed up pushing a palette jack with a huge pile of the beasts stacked on it.  I had to make a couple of extra trips to schlep them all home. (BTW, new they sell for around $6000 each with all the accessories).

Same as Racal 199x counters, if there's no reference there's no CPU clock, simple as reseating the Bliley crystal in one OCXO on mine, both had blown 630mA fuses as well even though they were set for the correct voltage. Simple fixes which got me some lovely counters.

Nice win on the 'scopes too, unfortunately it's more likely to be the other way round here in the UK, equipment set for 110 and blown up because it's been fed 240.

[CJay]

A good example was the photocopier that Dave found in his dumpster room.

He had a peek inside and found a paper jam. Once the rebellious piece of paper was removed the photocopier worked just fine and still had plenty toner left in it.

People's attitudes to printers and copiers are weird though, they get ridiculously overwraught about them.

Even if you can prove they don't fail as often as they think it becomes almost impossible to turn the tide of ill will so sometimes it's just easier to replace them (that's not to say I've not just shuffled them around departments after some judicious maintenance though...)

[GreyWoolfe]

Could this even be considered a repair?  Or simply a bit of maintenance.

One man's maintenance is another's repair. Unfortunately, too often even these levels of intervention are generally treated as catastrophic failures destined for the bin. So sad.

Thankfully, it ended up at the surplus store instead of the bin.  That gave it a new lease on life.  I am waiting for payday on Friday, they have an HP 13 MHz function generator for $40 USD that has 2 broken button caps on it.  A small screwdriver will operate the switches.  I plan to bring my DSO and a cable to see if it actually outputs anything.  I do have a frequency counter to go with it If it works and I decide to buy.

[bitseeker]

People's attitudes to printers and copiers are weird though, they get ridiculously overwraught about them.

...just shuffled them around departments after some judicious maintenance though...

That's excellent!

I am waiting for payday on Friday, they have an HP 13 MHz function generator for $40 USD that has 2 broken button caps on it.  A small screwdriver will operate the switches.

Very nice. Hope you score it.

[james_s]

I've lost count. I've received "broken" equipment that turned out to have no fault at all. I was once given a car that had broken down and I fixed a solder joint in the fuel pump relay in about 5 minutes and drove it home.

[TheWelly888]

Slightly tricky diagnosis but a dead easy repair of an electrical fault on my car several years ago.

I had a Ford Fiesta and one day the rear wiper and screen heater would not work at all. Fortunately I had a Haynes manual for that particular model and it included a circuit diagram - I found that the three contacts in the hatch were all used, two for the wiper and wiper parking and the rear heater but I realised that the common return were all through the hinges of the hatch into the body of the car. The hinges were rusty and so must have broken the circuit - all I had to do was to apply copper grease to the hinge rubbing faces and work them. They all worked perfectly afterwards!

Sadly I wrote the car off by driving off a sharp bend into a field a few months later.

[texaspyro]

I had a Ford Fiesta

My sincerest condolences...   

[Gyro]

Yes, that was a really lousy design. If my son's Fiesta was anything to go by, it contributed to rusting of the tailgate too! On his, the shaft seal leaked too and the wiper motor gears filled with water. The auto-return switch segment on the gear was made of....... wait for it....... Steel! 

[Oldtestgear]

I used to do contract repairs for a couple of Cal. Labs. One of these had a "faulty" HP 4274A which was offered to me for £20. This was about 8 years ago & prices were higher. Got it home, pulled the covers off & removed the (very flat) battery backing up the SRAM. Message immediately disappeared & it has been working ever since. The battery only holds data for limits etc. & was an option. Working & back in the case in about 15 minutes.  Certainly the cheapest repair I have done.

Phil

[bitseeker]

Hehe, nice one, Phil.

[andy2000]

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.

The easiest repairs are the ones where you can't find anything at all wrong.  My Fluke 189 came from a lot of e-waste, and I never did find a problem with it.  Probably user error, bad batteries, or an employee who wanted a newer model.

Earlier in the year I bought a fairly new 60" Samsung plasma TV for $30 off Craigslist.  When I got there, I discovered he was a tinkerer who had tried to fix it.  He said his boss gave it to him because of an intermittent issue that eventually became full time.  He couldn't see any obvious problems (like bad caps) so here it was.  I didn't have high expectations, but it was cheap.  When I took the back off, I quickly narrowed it down to a missing Vs supply.  As soon as I pulled the power supply, I found a very obvious bad solder connection on a power transistor.  I confirmed that the transistor wasn't shorted, and resoldered it, and it's been working fine since then. 

[Neomys Sapiens]

Oltronix B32-10 Laboratory Power Supply. Sold on Ebay as 'defective'. further stating, that 'voltage breaks down about mid-range'. There were even photographs with real good resolution. Looked at them, determined that the recessed front panel pot for the overvoltage protection (crowbar) is set about mid of it's adjusmend range.
Bought the unit, set crowbar to full CW, tested: GO.

Rohde&Schwarz Power Supply NGR20 on a Ham fleamarket, the seller started fo fidget when asked if it works by someone he obviously knew. Originally, he wanted 100€ for it. I jumped in, paid 40, came home, looked at the unit, moved the slide switch, which selects Sense int/ext two or three times to and fro: working flawlessly since then.

Siemens Multizet A1001 DC electronic multimeter, advertised as defective 'doesn't measure'. Was shown to switch on and give range indication on the secondary LCD. This LCD has a fuse symbol, which is shown when fuse is blown (or missing). This was clearly lit. Got the instrument, checked fuse (missing), replaced with the untouched, original spare fuse from the spare fuse holder: working, all nominal and within spec.

[Neomys Sapiens]

'Broken' M22520/7-01 Daniels Milspec crimping pliers (the green mid-range one): received and saw two-part spring in release mechanism. Two-part spring? Broken spring! Incidentally, I had much business with the company representing them in Germany, asked for a spring, received one, replaced it and DONE.

[iampoor]

Every repair is easy, only you need practice and experience in repairing, then every repair is like a twitch.

Sounds like you do not have much experience with repair then. 

[vk6zgo]

 ::)A couple more easy ones:-

HP N&D set kept blowing Mains fuses.
Opened it up, found that an internal panel could sometimes flex enough to hit the back of the fuse holder.
I glued a piece of perspex on the panel just behind the fuse holder.*

Icom IC 910 Ham Transceiver made clicking noises & overheated.

Repositioned the ribbon cable which was fouling the fan.

* Thinking back, either HP stuffed up the connections on the fuse holder, ( the incoming Mains should be on the centre pin), or it was the rack fuse that was blowing.

Too long ago.

[SaabFAN]

PC had very erratic behavior - it would sometimes run for hours and then suddenly shut off, or power on and immediately power off again.

On a hunch I measured the voltage at the power-button pins and discovered that the power button didn't disconnect properly. Even when not pressed, it still had a resistance of some 10k Ohm. Enough to pull the Powerbutton-Input low enough for the Mainboard to occasionally trip and regard the signal as the button being pushed.
Repair was easy: Set power-supply to 15V, 1A and connect the power-button to it. Zapped it and since then no more problems

[DrGeoff]

Plasma 46" TV from the roadside. DOA.
30 minutes and a 6 cent diode in the PSU and we have a nice working TV

[Tom45]

When I was an EE student in college over 50 years ago, I was asked to help with the repair of a Knight stereo amplifier another (and younger) EE student had built from a kit. It had never worked, so it was an error in building the kit.

Several guys had tried for days to find the defect, and they were referred to me after having given up.

I grabbed a screwdriver and with my finger on the shaft, I touched each grid starting from the output tube and working back towards the input stage. When I no longer heard hum and static when touching a grid I knew which stage wasn't working. A close inspection of that stage showed a solder blob that was shorting the signal. I pointed out the blob and told the guy to fix it.

They had spent several fruitless days, but I had the answer in a few minutes with no test equipment other than a screwdriver and my ears.

Those Knightkit amplifiers usually had some audible hum. I improved quite a few of them by replacing the power supply filter caps with larger values.

[Cubdriver]

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.

The easiest repairs are the ones where you can't find anything at all wrong.  My Fluke 189 came from a lot of e-waste, and I never did find a problem with it.  Probably user error, bad batteries, or an employee who wanted a newer model.

Earlier in the year I bought a fairly new 60" Samsung plasma TV for $30 off Craigslist.  When I got there, I discovered he was a tinkerer who had tried to fix it.  He said his boss gave it to him because of an intermittent issue that eventually became full time.  He couldn't see any obvious problems (like bad caps) so here it was.  I didn't have high expectations, but it was cheap.  When I took the back off, I quickly narrowed it down to a missing Vs supply.  As soon as I pulled the power supply, I found a very obvious bad solder connection on a power transistor.  I confirmed that the transistor wasn't shorted, and resoldered it, and it's been working fine since then.

As for the ones that are supposed to be easy, they're often a laugh.  The seller says "it's not working, but it's just a blown fuse."  I think "If that's all it is, then why don't you replace the less-than-$1.00 fuse and then sell it as working?"  Seems you'd get a lot more than that $1.00 invested in that fuse as a return for selling a working unit vs a non-working unit.   

   I was born at night, but it wasn't last night...   

-Pat

[LazyJack]

As for the ones that are supposed to be easy, they're often a laugh.  The seller says "it's not working, but it's just a blown fuse."  I think "If that's all it is, then why don't you replace the less-than-$1.00 fuse and then sell it as working?"  Seems you'd get a lot more than that $1.00 invested in that fuse as a return for selling a working unit vs a non-working unit.   

   I was born at night, but it wasn't last night...   

-Pat

Yeah, it is pretty much the same, when people selling cars, and say the AC just needs to be refilled with refrigerant to get it working. Any time I say, OK, then please have it refilled and deduct the refill price (which is peanuts...) from the price of the car, they always miraculously back down from the sale. Without of course admitting the gaping hole in the AC radiator or the seized as rock compressor.

[CatalinaWOW]

Of course I have sold a few as non working because the fuse holder was missing, difficult to replace and I just didn't want to fool with it.  No claims on whether anything other than the fuse is defunct.

This would be a dumb move on my part if I was running a business, but it is a hobby and if it isn't fun it isn't happening.

The same happens in reverse.  I have done several non-economic repairs because I was interested in the result or enjoyed the challenge.

Bottom line - if you want a really smoking good deal you have to take some chances.  In Yankee vernacular you will whiff a few balls between the home runs.

[james_s]

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!"