What did you last repair?

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Joined 2004
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Hi Nigel,
That was a tougher repair than most where you get it before someone else has been in there. If the number had been on the part it probably would have struck you right away. But part numbers don't come off semiconductors unless someone grinds them off, so not only was the part the wrong polarity, but it was probably a remarked part that threw off the original repair person.

-Chris
 
Hi Nigel,
That was a tougher repair than most where you get it before someone else has been in there. If the number had been on the part it probably would have struck you right away. But part numbers don't come off semiconductors unless someone grinds them off, so not only was the part the wrong polarity, but it was probably a remarked part that threw off the original repair person.

-Chris

It was a round metal can so the number would just be ink that rubbed off in those days. It had a round heatsink on it so maybe that rubbed off the ink ?

Its the amp on the top right side. The two transistors near the bottom with round heatsinks.
The one on the left was wrong type but the other was fine.
maplin-3amps.jpg
 
repairs

Last repair?, the other day I changed out a dual SPST wall-switch . "Why is the dining-room light not on, do you live in a cave?...Oh, I see...". Also, changed out the wall switch/outlet in the bathroom...the outlet had "collapsed", trying to push the whole assembly inside when trying to plug in anything.

--------------------------------------------------------------------------Rick......
 
Just to be clear, the Atlas V is not 50yr old design? - but the Saturn heavy lift certainly is. Do I understand correctly that there are still three of these fully built and ready to go - or as close to that as something mothballed for that long can be?
Five F1s firing at once must have been something to behold.
 
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Joined 2015
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Today's repairs: replaced the faulty automatic document feeder unit from a office multifunction printer; then replaced the stuck cooling fans inside the touch screen operator panel of a industrial machine; and finally replaced several backup batteries from handeld mobile computers. The last audio related repair was last month; a complete recapping job on a Pioneer SA500 integrated amplifier. I then had to change all the small bjt transistors because they became noisy after almost 50 years. I'm surprised by how good this little amp sounds.
 
A 1 Spot Pro CS12 guitar pedal power supply. I broke it, too - plugged in to 240Vac without switching the voltage from my 120Vac 'home' setting.


Most of the outputs are on switching supplies that don't even see the voltage selection switch, but there's a 9Vac output fed by a small toroid. That appeared to have burned (shorted or open, I forget) along with the PCB-mount fuse, which killed the whole device.


Fortunately Newark had a suitable replacement toroid.
 
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Hi soundchaser001,
Normally a high level signal, like line level, will not harm the low level chips. They will clip, that's all. Not unless you mean low impedance and high voltage like amplifier output signals. That has the capacity to burn out any protection diodes and the chips with ease.

-Chris
 
Member
Joined 2007
Paid Member
Hi soundchaser001,
Normally a high level signal, like line level, will not harm the low level chips. They will clip, that's all. Not unless you mean low impedance and high voltage like amplifier output signals. That has the capacity to burn out any protection diodes and the chips with ease.

-Chris

Hey Chris;

Pretty much that. Power amp into the LL inputs. There were no protection diodes. That was just my guess of the root cause. Not sure what else would have caused it otherwise. Maybe the first repair attempt simply broke more than it fixed :(.
 
Last repair?, the other day I changed out a dual SPST wall-switch .

Changed out yet still another switch in the shop. This is the 4th one I had fail just this summer. They were all Leviton 20A/277V spec grade units, put in when I built the shop in 2010. The highest load was 8 32 watt T8’s, and the one yesterday was running a 50VA control transformer (for the winch reversing relay). I expected better from these, but then again they did come from Home Depot.
 
Sofa & table rebuild (hope the post survives)

Original built from oak with wood doweling (sort of Shaker minimalist) 1979. Replaced worn upholstery / refinished wood 2018
 

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