Parts $$ + Labor $$ vs. replace.

[JohnRoberts]

I am often impressed by the disconnect between parts cost and labor to effect repairs.

I just repaired the fancy (probably too fancy) control board for my coffee roaster. It has a large LCD display, and three color LED backlight, just because they can...  Well the LCD color started acting flaky making random colors, and I was fearful that the LCD was damaged from the cold temps this winter, but upon closer inspection I found that the LED back light was driven by a transistor array that had decided to malfunction.

Long story short I repaired the control board by replacing the $0.60 LED driver array. A replacement control board would have cost me $200...  So $0.60 + a couple hours of my time to reverse engineer the circuit and find the faulty component.

=====

Another similar repair where a minor part caused the malfunction. A year ago or more I repaired my neighbors electric wheelchair  battery charger. Another case where I had to reverse engineer the circuit to find the faulty part. In that case it was bad resistor, so more like a $0.02 parts cost....

====

We have all seen repairs that were $0 parts cost, where the product was fixed by reseating the ICs or touching up tired solder connections.

What was your cheapest and most satisfying repair?

JR

 

[12afael]

I bought an Blackstar HT5 5watt tube amp for $120 US at ebay I had to replace an internal PCB mounted fuse provably $0.5

I have an beringer BCF2000 surface controller, I bought it used and working and I manage to damage it minutes from having it, one trancistor went bad, I repair it very fast even without an schematic it felt good

 

[JohnRoberts]

Yup, back in the old days hand drawn schematics weren't very accurate, so we still had to be able to figure out what the actual circuit was doing, sometimes despite the schematic.  8)

JR

 

[Andy Peters]

What was your cheapest and most satisfying repair?

A few years ago I was getting into DAW mixing and like everyone I got tired of the mouse and looked for a control surface. (And yes, I seriously thought about DIY, but I couldn't find documentation for the HUI protocol anywhere.)

I went to the local Guitar Center to see what they had. I didn't expect to find anything affordable (I didn't want to drop over a grand into something I would use occasionally), but in their recording room they had a Mackie Control Universal for $299 with a sign that said "channel 3 fader scratchy."

For a device which doesn't pass audio, "scratchy pot" makes no sense, but I figured that I'd be way ahead even if I had to give Mackie $50 for a fader. I asked the sales guy what that meant, and he wasn't sure and said that it gave an error message at startup. We powered it up and sure enough  it threw an error, about fader calibration. At boot it moves each fader to the top of its travel and back down, I noticed that the fader in question barely moved.

I bought it, made them throw in a USB-MIDI interface, and took it home. I opened it up and took out the fader, and realized that the plastic dust dam was pinching the knob shaft.  Three seconds with an x-actor knife and it was fixed. Been using it ever since.

Whatever you think of Mackie, the Mackie Control Universal is a great piece of kit.

-a

 

[pucho812]

my most satisfying repair would have been my first one. It sure wasn't the cheapest by any means but it did open up a new way of thinking for me. 

 

[desol]

My Samsung SCX-4521 printer started acting up a while ago, not loading paper, giving errors, etc, so I decided to try my hand at fixing it rather than throwing it out or taking it in.

Disassembled the unit and found that some of the transistor legs, few legs on an IC and a couple jumpers had been eaten through from a coke I had spilled on it a long while back. I thought I had cleaned it up well enough, but apparently not.

Re soldered all the legs and jumpers as best I could, cleaned up the rest of the board with contact cleaner....turned it on and it worked perfectly.

Got a few more stories, but can't think of them all at the moment.  

 

[Ethan]

I feel I've gotten the best cost/benefit (satisfaction) ratio from fixing major appliances...most of which are still pretty low tech. The nylon motor coupler on my washer, $2. Dip tube and thermistor on my water heater, $15.  New thermometer/sensor for my refridgerater, $30. New draft motor for heater, $80.
All relatively easy fixes, but I can certainly understand why a repair tech would charge a minimum of a couple hundred bucks for the time and expense it takes to drive out, diagnose the problem, then actually do the repair. But if the appliance is more than a few years old, and the cost of replacement parts is more than half the price of a new unit, I'd be tempted to just replace the appliance.

 

[Ethan]

My scan/copy/fax/printer on the other hand...  I saw a newer model at Costco for $89.99, so that was an easy replacement choice,considering I paid $500 for mine a decade ago.

 

[hazel]

Few years ago i found a 200W per channel power amp beside a trash can on the street in front an electronics store i use to get components, they told me: "it's from a customer, he just threw it. Get it if you want to"

ISSUE: cold solder joint on binding posts

RESULT: didn't work at all

SOLUTION: a couple of solder and...voila! 200W/ch for free!

 

[JohnRoberts]

I've told this story before, but speaking of appliances I am reminded of my first appliance repair. I was just a teen and the family dishwasher was not working properly. My mother called in the repair man who said it couldn't be fixed, and she would have to buy a new dishwasher. I then asked if I could try to fix it, since it was going to be junked anyway. I traced the problem to a burned up switch contact in a motor driven timer switch that opened and closed the water valve solenoid.  Taking the switch apart I noticed that the switch was double throw, with contact buttons on both sides of the switch arm, but only one side was used, and burned up. The switch arm was symmetrical, so I just pulled it out, flipped it upside down, so now the unused contact was on the working side, and replaced it. The dishwasher worked perfectly for years after that.  I wish I was a fly on the wall to hear when my mother told the repair man that she wouldn't need to buy a new dishwasher because her young son had fixed the broken dishwasher for free.

JR

PS: Knowing what I know now, I would probably add a cap across the switch to reduce arcing, but I was just a young puke.

 

[djgout]

When I got my Yamaha M1532 there were 3 faders that wouldn't move at all. It came from a rental place and they were just clearing some stuff out. I was able to talk the guy down about $200 because I told him it'd be tough to find the replacements and have to order from japan or something. As soon as it was off my truck and into the house I pulled the channels and flipped them upside down and gave them a shake. The first module when shaken hard enough produced a dime from the fader, the next two each had a single penny. Once removed they worked fine. So that repair actually netted me $200.12!!

About a month ago our fridge starting not cycling into defrost so we had a repair guy come out. In about 10 minute he said *hate to do it but we'll have to replace the control board, it'll be $170*, I gritted my teeth and paid for the part and the labor for him to come back out and replace it. I had him give me the old control board and took a quick look, it was a failed electrolytic, all of a $0.21 part, and of course I had a bag of suitable replacements sitting 10 feet away in my shop the whole time.....pretty much washed out the saving on the console right there!

 

[jensenmann]

I often see defective gear appear at ebay because people don´t want to invest in costly repairwork. At a professional repairshop you have to expect that prices are higher than the real value of older pieces. So off it goes to ebay. Lately I picked up a defective Klark DN27 for <50€, replaced a 5532 and everything worked fine again.

 

[Mbira]

I can't answer what was muy most satisfying, but I have often found myself in the position (when I did a lot of guitar amp repair work) where I'd just tell people up front "look, this repair will probably be $2 in parts, but I will charge you $100 for the work"  I just tell them that right up front so there is no surprises. 

 

[JohnRoberts]

I just fixed one of my solar powered driveway lamps that stopped working last night... It was only $5 new but I felt like seeing how it was designed anyhow.

Pretty simple, a solar panel charging a battery through a diode, the battery feeds a charge pump that lights the LED, and that charge pump is turned off by a separate LDR.

I would have used the solar array output voltage but apparently they were able to make it profitably, using separate sensors.

I looked like some tin whiskers inside, but that was not the problem.

The LDR was too low Z even when dark... I removed it and it looked like it was completely encapsulated by a clear conformal coating... I scraped between it's two leads and bingo it started working again...

I must have very conductive dirt where I live, my lawnmower still suffers from leaky resistance in the kill switch circuitry.

I expect this driveway lamp to fail again, and when it does I may re-design the LDR out completely and sense for voltage across the solar cells.

I probably spent more than the initial purchase price in my time spent to fix this, but it is always interesting to dissect deep value engineering.

I could have done it even cheaper.  8)

JR

[edit  Light did not work again last night... looks like time for plan B... [/edit]
[edit 2 Took it inside the house and it's working again... WTF?  [/edit]

 

[ruffrecords]

I recently fixed my rechargeable battery shaver. It was getting slower and slower and the battery was starting not to hold so much charge. I took it apart and found the battery pack consisted of a pair of AAs soldered together. I replaced them with a couple of spare rechargeables I had lying around, oiled the mechanism with my wife's sewing machine oil and voila - new shaver.

Cheers

Ian

 

[JohnRoberts]

I recently fixed my rechargeable battery shaver. It was getting slower and slower and the battery was starting not to hold so much charge. I took it apart and found the battery pack consisted of a pair of AAs soldered together. I replaced them with a couple of spare rechargeables I had lying around, oiled the mechanism with my wife's sewing machine oil and voila - new shaver.

Cheers

Ian

My electric toothbrush was losing torque so about once every two weeks or so, I turn it on and let it run until it completely discharges. When it charges back up it is strong again... I probably need a new one, but for now it is acceptable.

JR

 

[JohnRoberts]

Despite the intermittent operation (works inside on my bench) I redesigned the turn off circuit to use two transistors (that I have laying around) instead of the LDR (that I don't),

So now it charges the battery through the base emitter junction of a PNP that also gives me a logic high from the PNP collector that I feed to a NPN (through a resistor)  to turn off the lamp while the battery is charging from the solar cell.

It worked OK last night... Turned on a little sooner than the other one still using a LDR. I might refine the design to sense directly across the  solar cell to turn on the lamp a little later.

I could do this all with one mosfet if I had the right sex laying around.  I might be able to use one of the uncommitted mosfets inside a CD4007 but that's awkward.  I use a SMD mosfet in my tuner but they are the wrong polarity for this. The nice thing about a mosfet is low low current. My transistors use a few microAmps... but I am not going to buy a part to fix a $5 driveway lamp.  ;D

JR

 

[gemini86]

I snagged an old motorola portable tube record player off craigslist a few years ago. It was non-working/ unknown condition. The old lady I got it from had bought it new in the 60s, IIRC. It used the typical 12ax7 preamp, el84 power amp for the "bass" channel and some 6BM8 tubes for the two stereo channels. I got it home, cleaned the moths out of it and found the rectifier rolling around in the bottom of the case. bent a couple pins a tad to get a snug fit, plugged it back in and fired it up. Worked just fine except for the scratchy old pots and the worn out needle. Now it has been torn apart to build 3 separate monoblocks and one HV bench supply.

I don't think I'll top that freebee score ever.

 

[lassoharp]

Once upon a hot summers day the central air stopped working around 2pm.  One of those days where the heat index was over 100 deg.  I troubleshot the thermostat - all good.  I remember walking outside in the miserable heat and thinking about the cost of a new compressor or fan motor which were the next possible culprits. $$$$$$$$.  I opened the control box and couldn't help but smile - a big bulging motor cap - prettiest thing I saw all day!  10 min later I was back from the store with a new cap and 10 min after that I had air conditioning again. Cap cost about eleven dollars and the cool air was priceless!


Gotta mention one just as good that unfortunately got away.  My Honda Accord had been prone to failing to start whenever the car sat in the sun too long on hot days.  I had been told by a Honda Tech what the likely cause was but it wasn't happening often enough to motivate me to investigate.  The car would eventually start after the doors were opened an it was allowed time to air out.  Then one day it happened and I couldn't get it started even after airing it out.  The car was parked in a place where the city would have towed it, I didn't have the right tools with me, and I had an appointment I was running late for already. I had to call mechanic to tow it in.  I told him to check the main relay/PGM board and what to look for.  My normal mechanic was not available and this guy didn't know Hondas very well.  He never bothered to check until after several hours of troubleshooting.  He had went ahead and replaced starter and finally remembered to check when nothing else worked.  Four cracked solder joints on the back of the board.  He did put back the old starter and didn't charge me for his misdiagnosis but it still wound up costing me nearly $400 for everything.  The replacement board was only about 45.00 and it really didn't even need that.  Coulda done it in a few minutes with a soldering iron and it wouldn't have cost me a cent. Lesson in preventative maintenance of lesser known problems.