^ Ouch!
My last repair was today on an Autoclave. A hydraulic piston blew a seal, so I unhooked it and now we can just manually open and close the door, much easier anyway.. Don't ya just love hydraulic oil all over the floor, wall, fun times
Reminds me of my dishwasher mess a few months ago...
During the last "empty" cycle, the output hose from the pump slipped off because the clamp was a bit loose, and/or the hose thickness "relaxed" over time.
No, the pump outlet port has no "ridges" to sink into the rubber, its smooth nylon.
What a nasty mess I had to clean up........ water all over the kitchen floor and coming down into the basement!
That hose is now tight, and I used adhesive gasket sealer too.
One of these (Otari MX-50N) purchased from a fellow in NJ that had rather extensive but random (salt) water damage. Fortunately it did not get to critical components.
Every single electrolytic replaced, a bunch of bearings, reel tables, and holders. Lots of cleaning with IPA and trouble shooting. I have a really pretty one, and a couple of others but this is the one I seem to use. It does sound pretty good actually, and gets a lot of use. (A few hiccups with the capstan motor deciding to run at 30 ips, now resolved.)
I relate to the dishwasher story - leaky fitting on the drain line into the sink waste line, same outcome, water all over the kitchen floor and into my basement electronics storage cabinets.
Every single electrolytic replaced, a bunch of bearings, reel tables, and holders. Lots of cleaning with IPA and trouble shooting. I have a really pretty one, and a couple of others but this is the one I seem to use. It does sound pretty good actually, and gets a lot of use. (A few hiccups with the capstan motor deciding to run at 30 ips, now resolved.)
I relate to the dishwasher story - leaky fitting on the drain line into the sink waste line, same outcome, water all over the kitchen floor and into my basement electronics storage cabinets.
Attachments
I built up a circuit board for a usb scope.
The pc said the scope was there but couldn't read its usb descriptors.
First problem was I hadn't set the clock to the crystal oscillator.
Then found the clock wasn't running right.
Turned out I missed a soldering a pin on the SMD microcontroller.
Then had trouble with the software displaying a very noisy sinewave.
Its seems for a dual channel A2D scope you read the A2D on both clock edges.
Alls well that ends well.
The pc said the scope was there but couldn't read its usb descriptors.
First problem was I hadn't set the clock to the crystal oscillator.
Then found the clock wasn't running right.
Turned out I missed a soldering a pin on the SMD microcontroller.
Then had trouble with the software displaying a very noisy sinewave.
Its seems for a dual channel A2D scope you read the A2D on both clock edges.
Alls well that ends well.
Marantz 4400 receiver. Powers up, no sound.
Just the fuse on the 35 V regulator. Corrected the voltage. Noting it had been "recapped" by someone, I went looking at the phono PCB. Sure enough, the 100R resistor was burnt to a crisp. Installed a new one, the filter cap on the phono board was in correctly, but I betcha one was originally put in backwards.
You know how if you go looking for trouble, you're sure to find it? I noticed the FM pointer was way off the proper place and it didn't line up with the reference mark. Re-positioned the pointer (one tab broke off), damn! Epoxied it into the right place and set the tracking. The osc cap trimmer was all over the place, so I cleaned the screw end carefully. Then it was all shifted right, but the cap was better. Cleaned the bearings in the tuning cap and gave it an hour, then aligned it all over again. A quick touch-up on the discriminator was done first, then touched up the distortion (Way off!) and optimized the sensitivity. Now it works really well.
One thing I didn't like were the lamps I was given to use in it. All cool white, including the function lamps. Now the pointer is a ghastly white and the function indicators all have bright spots along with an obvious white-blue hue. All that work to arrive at this. It was for a dealer, not my own customer. That doesn't make me feel much better.
I get that, people buying their own lamp kits off Ebay. They pretty much all look terrible compared to the lamps, or the LEDs I use and at the intensities I set. Too bad they can't just trust the tech to make intelligent choices for them.
One saw a receiver I had done my way and wanted to know why his looked so bad, then asked if I would exchange the lights and he would pay me ... for just the lights. Huh? His set still looks bad.
-Chris
Just the fuse on the 35 V regulator. Corrected the voltage. Noting it had been "recapped" by someone, I went looking at the phono PCB. Sure enough, the 100R resistor was burnt to a crisp. Installed a new one, the filter cap on the phono board was in correctly, but I betcha one was originally put in backwards.
You know how if you go looking for trouble, you're sure to find it? I noticed the FM pointer was way off the proper place and it didn't line up with the reference mark. Re-positioned the pointer (one tab broke off), damn! Epoxied it into the right place and set the tracking. The osc cap trimmer was all over the place, so I cleaned the screw end carefully. Then it was all shifted right, but the cap was better. Cleaned the bearings in the tuning cap and gave it an hour, then aligned it all over again. A quick touch-up on the discriminator was done first, then touched up the distortion (Way off!) and optimized the sensitivity. Now it works really well.
One thing I didn't like were the lamps I was given to use in it. All cool white, including the function lamps. Now the pointer is a ghastly white and the function indicators all have bright spots along with an obvious white-blue hue. All that work to arrive at this. It was for a dealer, not my own customer. That doesn't make me feel much better.
I get that, people buying their own lamp kits off Ebay. They pretty much all look terrible compared to the lamps, or the LEDs I use and at the intensities I set. Too bad they can't just trust the tech to make intelligent choices for them.
One saw a receiver I had done my way and wanted to know why his looked so bad, then asked if I would exchange the lights and he would pay me ... for just the lights. Huh? His set still looks bad.
-Chris
Marantz 4400 receiver. Powers up, no sound.
Just the fuse on the 35 V regulator. Corrected the voltage. Noting it had been "recapped" by someone, I went looking at the phono PCB. Sure enough, the 100R resistor was burnt to a crisp. Installed a new one, the filter cap on the phono board was in correctly, but I betcha one was originally put in backwards.
You know how if you go looking for trouble, you're sure to find it? I noticed the FM pointer was way off the proper place and it didn't line up with the reference mark. Re-positioned the pointer (one tab broke off), damn! Epoxied it into the right place and set the tracking. The osc cap trimmer was all over the place, so I cleaned the screw end carefully. Then it was all shifted right, but the cap was better. Cleaned the bearings in the tuning cap and gave it an hour, then aligned it all over again. A quick touch-up on the discriminator was done first, then touched up the distortion (Way off!) and optimized the sensitivity. Now it works really well.
One thing I didn't like were the lamps I was given to use in it. All cool white, including the function lamps. Now the pointer is a ghastly white and the function indicators all have bright spots along with an obvious white-blue hue. All that work to arrive at this. It was for a dealer, not my own customer. That doesn't make me feel much better.
I get that, people buying their own lamp kits off Ebay. They pretty much all look terrible compared to the lamps, or the LEDs I use and at the intensities I set. Too bad they can't just trust the tech to make intelligent choices for them.
One saw a receiver I had done my way and wanted to know why his looked so bad, then asked if I would exchange the lights and he would pay me ... for just the lights. Huh? His set still looks bad.
-Chris
Yes Chris, some of us techs do prefer to be "detail oriented" in our work.
I'm just as fussy as you in that respect.
As for the change to LED lighting, at times I install a frosted "diffuser" to eliminate/minimize the "beaming" effect of the LEDs.
Old flat screen monitor panels have a frosted sheet layer in the screen if you tear into them, or art supply stores have such sheets.
Those "fuse style" LED lamps from Parts Express - I cut a strip of frosted sheet long enough to slide into the end caps and wide enough to cover the LEDS - works great.
Other times, I'll "shave off" the convex lens end of a single LED to eliminate beaming.
It all depends on the result that I'm after.
Careful use of a Dremel with a cutoff wheel is good for that.
Hi wiseoldtech,
Yes, I would normally replace the vellum. Mine is from Germany, archival grade. The LEDs I use are "flat faced" as well, although the fuse lamps are fine the way they are.
I use individual lamps so I can set the current level myself if possible. You get a much better result that way.
Yes, detail work makes all the difference, but adds to service time quickly if you aren't careful.
-Best, Chris
Yes, I would normally replace the vellum. Mine is from Germany, archival grade. The LEDs I use are "flat faced" as well, although the fuse lamps are fine the way they are.
I use individual lamps so I can set the current level myself if possible. You get a much better result that way.
Yes, detail work makes all the difference, but adds to service time quickly if you aren't careful.
-Best, Chris
Solartron 7140 DMM. Input resistance 7.5kohm instead of 10M. Not showing "infinite" in ohms range.
At the end it was a heavily burned Plessey rotary switch, well hidden under a shield that was a nightmare ro remove. The burned disc of the switch showed 7.5 kohm between adjacent wipers, that was the resistance of the PCB that became charred There must have been really high voltage that caused arcing there. Fortunately no other component harmed.
I scratched away the charred bridge between the contacts, reassembled, and now it works!
At the end it was a heavily burned Plessey rotary switch, well hidden under a shield that was a nightmare ro remove. The burned disc of the switch showed 7.5 kohm between adjacent wipers, that was the resistance of the PCB that became charred
There must have been really high voltage that caused arcing there. Fortunately no other component harmed.I scratched away the charred bridge between the contacts, reassembled, and now it works!
Sorry I never got a notice for this reply. I can relate as the same thing happened to me once as well. And worse was coming home to a washing machine hose that gave way at some point while I was at work, turning my then residence into a mini Niagara Falls, that was a bad one..
Attempted repair between Uk and Paraguay of two IGBT power amplifiers.
First one burned the source resistors.
Second one lasted quite a while before doing the same.
Power supply volts are correct.
Wired correctly.
Swears he didn't fiddle with bias control trimmer.
Insulation pads between output transistors and heat sink.
Correct heat sinks.
First one burned the source resistors.
Second one lasted quite a while before doing the same.
Power supply volts are correct.
Wired correctly.
Swears he didn't fiddle with bias control trimmer.
Insulation pads between output transistors and heat sink.
Correct heat sinks.
Thanks for reminding me......
I've got a 1984 Maytag (god bless its soul) with likely the original water hoses on it.....(it came with the house) and keep forgetting to put new hoses on my shopping list.
Thanks for reminding me......
I've got a 1984 Maytag (god bless its soul) with likely the original water hoses on it.....(it came with the house) and keep forgetting to put new hoses on my shopping list.
For sure! I think that most everyone never thinks of the hot and cold water hoses connecting the washing machine to an unlimited supply of free running water if one were to blow, I know I never did lol. I'm just glad I wasn't away for a few days or something, that would have really been bad.
I have a Maytag as well circa late 70's I think?. Got it used 8 years ago from a paramedic who had an ad for the washing machine for sale. It just keeps on going and going and cleans really well. They just don't make em like that anymore! Now you get thin metal and circuit boards that seem to last a few years or more before problems start etc.
Anyhow yes, replace them hoses and you're probably set for another decade or more plus some peace of mind
A Tandberg TR 2075. Not a joy to fix even though access to boards isn't bad. It turns out that a solder monkey had been loose inside this thing. It had three faults, one a broken solder connection on a plug for the LEDs, a short in the preamplifier PCB and solder splash on the Mode/Filter PCB. Not surprising, given how much solder was used (excessive). These are some of the less accessible PCBs.
Given the trouble it was getting into it, and the history of intermittent faults, I replaced the electrolytic capacitors. The ones with voltage ratings less than 16 V are prone to going bad, although when tested they were okay in this one.
So now it's working normally. It doesn't sound very good and measurements bear that out. I can't understand why it is a cult hit. It looks neat, but controls feel CHEAP! and the buttons are clunky on top of that. Finally, it is the sound quality that is in the basement.
-Chris
Edit: It didn't help that this one doesn't match the service manual, or the MK II version manual. Wrong right where I was working. Got to love these guys.
Given the trouble it was getting into it, and the history of intermittent faults, I replaced the electrolytic capacitors. The ones with voltage ratings less than 16 V are prone to going bad, although when tested they were okay in this one.
So now it's working normally. It doesn't sound very good and measurements bear that out. I can't understand why it is a cult hit. It looks neat, but controls feel CHEAP! and the buttons are clunky on top of that. Finally, it is the sound quality that is in the basement.
-Chris
Edit: It didn't help that this one doesn't match the service manual, or the MK II version manual. Wrong right where I was working. Got to love these guys.
Chris, the "mindset of the masses" are tuned to certain ideas as a result of hype, bias, and the human trait (weakness) of superficiality.
Someone, somewhere, likely on the internet, or previously in a magazine publication, has deemed that a given product is wonderful.
And with that, the product is sought after, priced up high (sometimes as a result of rarity) and then eventually it becomes some sort of a legend.
It's got nothing to do with actual performance or function in most cases, but merely because "someone said" it was great.
It's easy to fall for such crap, as is the marketing of snake oil.
Because people in general are uneducated/ignorant of actual facts and figures, and/or in denial of real-world quality.
