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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Component Damage
One of the books I picked up on faultfinding and troubleshooting whilst
in London the other day (title escapes me but I can find it if anyone cares) states that: a) A bipolar transitor may be permanently damaged by dropping it on a concrete floor from a height of over 4'. (I'm paraphrasing but that's the gist of it). Elsewhere it states that: b) static sensitive components can be damaged by careless use of air dusters, which can build up a static charge, in their vicinity. Whilst I'm prepared to place some faith in assertion b) I'm reluctant to do so in the case of a). However, I'm more concerned with b) because I recently purchased a fair sized air compressor for blowing dust out of the insides of test equipment which is of course considerably more powerful than the aerosol cans the author was thinking about when he asserted b). Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? |
#2
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Component Damage
On Tuesday, 13 June 2017 21:24:50 UTC+1, Cursitor Doom wrote:
One of the books I picked up on faultfinding and troubleshooting whilst in London the other day (title escapes me but I can find it if anyone cares) states that: a) A bipolar transitor may be permanently damaged by dropping it on a concrete floor from a height of over 4'. (I'm paraphrasing but that's the gist of it). Elsewhere it states that: b) static sensitive components can be damaged by careless use of air dusters, which can build up a static charge, in their vicinity. Whilst I'm prepared to place some faith in assertion b) I'm reluctant to do so in the case of a). However, I'm more concerned with b) because I recently purchased a fair sized air compressor for blowing dust out of the insides of test equipment which is of course considerably more powerful than the aerosol cans the author was thinking about when he asserted b). Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT |
#3
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Component Damage
On 14/06/2017 6:21 AM, Cursitor Doom wrote:
One of the books I picked up on faultfinding and troubleshooting whilst in London the other day (title escapes me but I can find it if anyone cares) states that: a) A bipolar transitor may be permanently damaged by dropping it on a concrete floor from a height of over 4'. (I'm paraphrasing but that's the gist of it). Elsewhere it states that: b) static sensitive components can be damaged by careless use of air dusters, which can build up a static charge, in their vicinity. Whilst I'm prepared to place some faith in assertion b) I'm reluctant to do so in the case of a). However, I'm more concerned with b) because I recently purchased a fair sized air compressor for blowing dust out of the insides of test equipment which is of course considerably more powerful than the aerosol cans the author was thinking about when he asserted b). Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? **a) is possible (barely). Rip the top off a TO3 transistor and examine the construction. You'll get the idea. As for b), I have no idea why any sane person would use compressed air on any product, unless required by very specific circumstances. It is a daft idea. A soft brush and a vacuum cleaner is a far superior and gentler way to do things. Even better, there is far less chance that the dust will end up inside pots, switches and other mechanical components. -- Trevor Wilson www.rageaudio.com.au |
#4
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Component Damage
On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote:
I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT Haha! I think even those old germanium diodes would easily cope with a four foot fall! |
#5
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Component Damage
Cursitor Doom wrote:
One of the books I picked up on faultfinding and troubleshooting whilst in London the other day (title escapes me but I can find it if anyone cares) states that: a) A bipolar transitor may be permanently damaged by dropping it on a concrete floor from a height of over 4'. (I'm paraphrasing but that's the gist of it). Elsewhere it states that: b) static sensitive components can be damaged by careless use of air dusters, which can build up a static charge, in their vicinity. Whilst I'm prepared to place some faith in assertion b) I'm reluctant to do so in the case of a). However, I'm more concerned with b) because I recently purchased a fair sized air compressor for blowing dust out of the insides of test equipment which is of course considerably more powerful than the aerosol cans the author was thinking about when he asserted b). Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? The original, point-contact trasnsistors from the 1950's were quite fragile devices, basically a pair of etched hair whiskers on a Germanium speck. Supposedly, it is the tiny dust particles in an air stream that create the triboelectric charge. So, clean air should be better. I live in Missouri, so we have enough humidity that ESD is a fairly rare phenomenon. I have used vacuum cleaners to clean old computer gear, and never had damage, although I was concerned about the possibility. I have seen a fat spark produced when firing off a CO2 fire extinguisher, which seemed like a pretty big design defect. They should have made the hose and nozzle with a static dissipative material. Jon |
#6
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Component Damage
On Tuesday, 13 June 2017 22:03:32 UTC+1, Cursitor Doom wrote:
On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? Haha! I think even those old germanium diodes would easily cope with a four foot fall! I think those would be some of the more fragile items. Many have an extremely thin filament stretching a few mm with no support at all. NT |
#7
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Component Damage
On Wed, 14 Jun 2017 06:50:59 +1000, Trevor Wilson wrote:
I have no idea why any sane person would use compressed air on any product, unless required by very specific circumstances. It is a daft idea. I beg to differ. Air compressors totally *rock*! Having used one now for 7 years I could not imagine going back to *any* other method. Nothing else comes close. |
#8
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Component Damage
On Tue, 13 Jun 2017 16:16:01 -0500, Jon Elson wrote:
so we have enough humidity that ESD is a fairly rare phenomenon. I have used vacuum cleaners to clean old computer gear, and never had damage, although I was concerned about the possibility. I'd be more worried about the action of brushing itself giving rise to static charges. It's hard to know for sure what I have seen a fat spark produced when firing off a CO2 fire extinguisher, which seemed like a pretty big design defect. Yes, been there; done that. In fact a gave a co-worker a pretty nasty shock by using a CO2 extinguisher which must have charged me up to 10s of thousands of volts whilst I put out a fire with it. It was a very noisy situation so I needed to shout into his ear to make myself heard and this terrific blue spark shot straight from my nose to his ear! Had no effect on me but sent him reeling. You should have seen the look on his face! :- |
#9
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Component Damage
On 14/06/2017 7:39 AM, Chris wrote:
On Wed, 14 Jun 2017 06:50:59 +1000, Trevor Wilson wrote: I have no idea why any sane person would use compressed air on any product, unless required by very specific circumstances. It is a daft idea. I beg to differ. Air compressors totally *rock*! Having used one now for 7 years I could not imagine going back to *any* other method. Nothing else comes close. **OK. I'll trade your 7 years with my 40 years professionally servicing electronic equipment. And yes, I have a (filtered) air line into my workshop. However, a vac is vastly more preferable and much safer. I do use air, very sparingly, when required. -- Trevor Wilson www.rageaudio.com.au |
#10
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Component Damage
On Tuesday, June 13, 2017 at 2:03:32 PM UTC-7, Cursitor Doom wrote:
On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? Haha! I think even those old germanium diodes would easily cope with a four foot fall! Oh, no; a point contact diode can easily jar out of spec. There was even an old device (the 'coherer') which reformed a rectifying contact by motorized shaking during normal operation. |
#11
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Component Damage
On Wed, 14 Jun 2017 08:49:40 +1000, Trevor Wilson wrote:
**OK. I'll trade your 7 years with my 40 years professionally servicing electronic equipment. And yes, I have a (filtered) air line into my workshop. However, a vac is vastly more preferable and much safer. I do use air, very sparingly, when required. Yeah, air is so expensive you gotta use it sparingly hehehe! The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. |
#12
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Component Damage
On 14/06/2017 9:02 AM, Chris wrote:
On Wed, 14 Jun 2017 08:49:40 +1000, Trevor Wilson wrote: **OK. I'll trade your 7 years with my 40 years professionally servicing electronic equipment. And yes, I have a (filtered) air line into my workshop. However, a vac is vastly more preferable and much safer. I do use air, very sparingly, when required. Yeah, air is so expensive you gotta use it sparingly hehehe! **Read what I wrote, moron. Using air spreads dust to places inside the equipment where you don't want it to go. Like pots and switches for instance. How do you prevent that from occurring? The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. -- Trevor Wilson www.rageaudio.com.au |
#13
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Component Damage
In article ,
Jon Elson wrote: I have seen a fat spark produced when firing off a CO2 fire extinguisher, which seemed like a pretty big design defect. You're certainly right - if you had used it around any sort of flammable vapors, the spark might have started a fire. ;-) They should have made the hose and nozzle with a static dissipative material. I'm not sure that would have helped. Where would the charge have gone, during the second or three that one was blasting away with CO2? There'd be only a very limited amount of charge flow back into the CO2 cloud (neither the CO2 nor the ice crystals which were triboelectrically active, will be particularly conductive), or dissipate into the air nearby. The major charge-sink would still be the body of the person wielding the extinguisher. http://www.ece.rochester.edu/~jones/demos/charging.html is interesting. Apparently, even aluminum can generate a charge via triboelectric effect, and it's about as static-conductive as you could ask for. |
#14
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Component Damage
In article ,
Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). |
#15
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Component Damage
On 14/06/2017 9:43 AM, Dave Platt wrote:
In article , Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. **I confess that I had not thought of that, but certainly, spreading any dust around can be injurious to many people. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). **Of course. And MUCH safer for the equipment. -- Trevor Wilson www.rageaudio.com.au |
#16
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Component Damage
On 6/13/2017 5:02 PM, Trevor Wilson wrote:
On 14/06/2017 9:43 AM, Dave Platt wrote: In article , Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. **I confess that I had not thought of that, but certainly, spreading any dust around can be injurious to many people. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). **Of course. And MUCH safer for the equipment. How do you get the cat hair out of the CPU heat sink underneath the fan? |
#17
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#18
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Component Damage
On Tue, 13 Jun 2017 20:59:53 -0000 (UTC), Cursitor Doom
wrote: On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT Haha! I think even those old germanium diodes would easily cope with a four foot fall! Dont try that with a vaccuum tube! |
#19
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Component Damage
On Wed, 14 Jun 2017 06:50:59 +1000, Trevor Wilson
wrote: I have no idea why any sane person would use compressed air on any product, unless required by very specific circumstances. It is a daft idea. A soft brush and a vacuum cleaner is a far superior and gentler way to do things. Even better, there is far less chance that the dust will end up inside pots, switches and other mechanical components. I have an air compressor at home, in my palatial office, and a small one in my car. It was one of the best purchases I ever made. Lots of benefits: 1. It totally eliminated black nose disease, where the dust found inside computahs, test equipment, and flea market junk does not end up being inhaled and producing a disgusting black goo when ejected by sneezing. 2. I blow out EVERYTHING that arrives in the office that has even the possibility of containing dust. The result is that I only have to vacuum the office perhaps every 2 months. 3. I don't worry much about static electricity, but I do watch the relative humidity. If it drops below about 20%, I start throwing lighting bolts of static electricity. At that point, I take precautions, like discharging myself, wearing anti-static shoe coverings, and generally avoiding anything risky. So far, I've only blown up a few things in 30+ years, none of which involved an air compressor. 4. I have an electrostatic voltmeter for measuring static buildup. Something like these but home made: https://www.google.com/search?tbm=isch&q=electrostatic+voltmeter I don't guess, I measure. 5. I frequently wash PCB's and equipment. Getting them dry takes some time. So, I speed things up by blowing the water out from under components and in inaccessible locations. Without compressed air, a keyboard wash takes about a week to dry completely. With compressed air, 24 hrs will usually do the trick. However, there are disadvantages: 1. Everyone in the building asks me to put air in their tires, especially the bicycle riders. I have 100ft of air hose so that I don't need to drag the compressor outside. 2. An air compressor and air tools are noisy but I'm good at ignoring complaints from the neighbors. 3. I have to remember to drain the condensed water out of the tank or I end up spraying rusty water on everything. I could get a filter/dryer, but don't want to spend my life cleaning them. Incidentally, I've convinced some friends and competitors to buy air compressors for their office or shop. All have been very successful. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#20
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Component Damage
On 14/06/2017 11:58 AM, mike wrote:
On 6/13/2017 5:02 PM, Trevor Wilson wrote: On 14/06/2017 9:43 AM, Dave Platt wrote: In article , Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. **I confess that I had not thought of that, but certainly, spreading any dust around can be injurious to many people. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). **Of course. And MUCH safer for the equipment. How do you get the cat hair out of the CPU heat sink underneath the fan? **I vacuum it out, possibly with the aid of a brush. -- Trevor Wilson www.rageaudio.com.au |
#21
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Component Damage
On Tue, 13 Jun 2017 20:21:10 -0000 (UTC), Cursitor Doom
wrote: Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? I worked in a factory once that did a lot of cleaning of electronic modules. Air was supplied by a central compressor. I never had a problem with static and I don't think anyone else did but how would we have known as many of the modules were already faulty. Steve -- Neural Network Software for Windows http://www.npsnn.com |
#22
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Component Damage
On Tue, 13 Jun 2017 14:38:44 -0700 (PDT), wrote:
On Tuesday, 13 June 2017 22:03:32 UTC+1, Cursitor Doom wrote: On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? Haha! I think even those old germanium diodes would easily cope with a four foot fall! I think those would be some of the more fragile items. Many have an extremely thin filament stretching a few mm with no support at all. NT Regards, Boris Mohar Got Knock? - see: Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca void _-void-_ in the obvious place --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
#23
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Component Damage
On 13/06/2017 21:21, Cursitor Doom wrote:
One of the books I picked up on faultfinding and troubleshooting whilst in London the other day (title escapes me but I can find it if anyone cares) states that: a) A bipolar transitor may be permanently damaged by dropping it on a concrete floor from a height of over 4'. (I'm paraphrasing but that's the gist of it). Elsewhere it states that: b) static sensitive components can be damaged by careless use of air dusters, which can build up a static charge, in their vicinity. Whilst I'm prepared to place some faith in assertion b) I'm reluctant to do so in the case of a). However, I'm more concerned with b) because I recently purchased a fair sized air compressor for blowing dust out of the insides of test equipment which is of course considerably more powerful than the aerosol cans the author was thinking about when he asserted b). Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? I've used a 1KW handheld Martindale blower for decades, no known static problem ,just occassional physical breakage of shielding or something like that, because of the air pressure involved, blowing out tarry/greasy/hairy crud. |
#24
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Component Damage
"Cursitor Doom" wrote in message news On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT Haha! I think even those old germanium diodes would easily cope with a four foot fall! diodes would be OK but die mounting and bond wires in some germanium transistors was well, err - a bit amateurish. Nowadays; suppliers pack *ANY* components in anti-static bags - it used to be some sort of clue which bits to handle with care. There's some unexpected parts on the vulnerable list, so maybe they have a point. molded semiconductors can be subjected to pretty much anything that doesn't break the case. |
#25
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Component Damage
wrote in message ... On Tuesday, 13 June 2017 22:03:32 UTC+1, Cursitor Doom wrote: On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? Haha! I think even those old germanium diodes would easily cope with a four foot fall! I think those would be some of the more fragile items. Many have an extremely thin filament stretching a few mm with no support at all. The first successful anti aircraft shell proximity fuze that could be fired out of a gun had 3 hearing aid style tubes. The thyratron obviously isn't a hearing aid tube - its about the sixe & shape of the glass envelope. |
#26
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Component Damage
"whit3rd" wrote in message ... On Tuesday, June 13, 2017 at 2:03:32 PM UTC-7, Cursitor Doom wrote: On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? Haha! I think even those old germanium diodes would easily cope with a four foot fall! Oh, no; a point contact diode can easily jar out of spec. There was even an old device (the 'coherer') which reformed a rectifying contact by motorized shaking during normal operation. AFAIK: the point is "burned in" during manufacture. The weld is pretty much the alloying process that creates the PN junction. They're much less fragile than the old catswhisker/galena crystal. |
#27
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Component Damage
wrote in message ... On Tue, 13 Jun 2017 20:59:53 -0000 (UTC), Cursitor Doom wrote: On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT Haha! I think even those old germanium diodes would easily cope with a four foot fall! Dont try that with a vaccuum tube! I've seen one or two bounce - not very often though. |
#28
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Component Damage
"mike" wrote in message news On 6/13/2017 5:02 PM, Trevor Wilson wrote: On 14/06/2017 9:43 AM, Dave Platt wrote: In article , Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. **I confess that I had not thought of that, but certainly, spreading any dust around can be injurious to many people. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). **Of course. And MUCH safer for the equipment. How do you get the cat hair out of the CPU heat sink underneath the fan? Its very easy when you don't have a cat - but since you do, odour killing cat litter is great for packing in gear that came from a heavy smoker household. |
#29
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Component Damage
"Trevor Wilson" wrote in message ... On 14/06/2017 11:58 AM, mike wrote: On 6/13/2017 5:02 PM, Trevor Wilson wrote: On 14/06/2017 9:43 AM, Dave Platt wrote: In article , Trevor Wilson wrote: The one caveat I would add about blasting boards with (clean) compressed air is that you *gotta* do it outdoors for all sorts of reasons I can't be assed to go into here. **And yet another good reason to use a vac. In particular: I'd be cautious about using compressed air to clean out electronic equipment that's been stored in sheds, barns, or other locations where there might be rodent activity. I've seen some pretty grotty equipment donated to our ham club, which I thought might well have been peed or pooped upon by rats and/or mice. Hantavirus is no joke. **I confess that I had not thought of that, but certainly, spreading any dust around can be injurious to many people. A vacuum, particularly one with a HEPA filter, would be safer than compressed air (either indoors or outdoors). **Of course. And MUCH safer for the equipment. How do you get the cat hair out of the CPU heat sink underneath the fan? **I vacuum it out, possibly with the aid of a brush. Since de fluxing solvents were banned to protect the ozone layer, most electronics is cleaned with water - sometimes its an option, sometimes it isn't. Dish wash detergent works great, but they thicken it with salt - so make sure you rinse it all out. |
#31
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Component Damage
"Dave Platt" wrote in message ... In article , Jon Elson wrote: I have seen a fat spark produced when firing off a CO2 fire extinguisher, which seemed like a pretty big design defect. The one I fished out of a skip is now fitted with a tyre adaptor and used for blowing tubeless tyre onto the rim. You have to hold it upside down - if the syphon tube puts liquid CO2 into the tyre, the rim starts creaking ominously. |
#32
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"Stephen Wolstenholme" wrote in message ... On Tue, 13 Jun 2017 20:21:10 -0000 (UTC), Cursitor Doom wrote: Has anyone ever caused damage to static-sensitive components through the use of compressed air? Is this something we really need to be mindful of? I worked in a factory once that did a lot of cleaning of electronic modules. Air was supplied by a central compressor. I never had a problem with static At tea break a bunch of us sat on the compressor - somehow I always ended up next to the intake filter, and I tend to fart. |
#33
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Component Damage
On Fri, 16 Jun 2017 21:48:37 +0100, Ian Field wrote:
molded semiconductors can be subjected to pretty much anything that doesn't break the case. Are you the same Ian Field that has authored several books on UHF/VHF subjects? |
#34
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On Sunday, June 18, 2017 at 11:44:48 AM UTC-4, Cursitor Doom wrote:
On Fri, 16 Jun 2017 21:48:37 +0100, Ian Field wrote: molded semiconductors can be subjected to pretty much anything that doesn't break the case. Are you the same Ian Field that has authored several books on UHF/VHF subjects? Plasma physics too... oh sorry that was Ion Fields. :^) George H. |
#35
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Component Damage
On 2017/06/16 1:48 PM, Ian Field wrote:
"Cursitor Doom" wrote in message news On Tue, 13 Jun 2017 13:45:40 -0700, tabbypurr wrote: I'd first be mindful of mechanical damage from doing that. When was the book written? Germanium? NT Haha! I think even those old germanium diodes would easily cope with a four foot fall! diodes would be OK but die mounting and bond wires in some germanium transistors was well, err - a bit amateurish. Nowadays; suppliers pack *ANY* components in anti-static bags - it used to be some sort of clue which bits to handle with care. There's some unexpected parts on the vulnerable list, so maybe they have a point. molded semiconductors can be subjected to pretty much anything that doesn't break the case. IC sockets though? Why do they pack them in anti-static bags (Digi-Key)! John ;-#)# |
#36
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Component Damage
compressed air can over-speed some small fans...
m |
#37
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Component Damage
On 6/19/2017 3:43 PM, John Robertson wrote:
IC sockets though? Why do they pack them in anti-static bags (Digi-Key)! John ;-#)# For the same reason drive through ATMs have instructions in Braille. One kind of something is cheaper to inventory than two kinds of something. If you don't inventory non-static bags, nobody gets sensitive parts in the wrong bags. -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com --- This email has been checked for viruses by AVG. http://www.avg.com |
#38
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Component Damage
On 2017/06/19 2:07 PM, Foxs Mercantile wrote:
On 6/19/2017 3:43 PM, John Robertson wrote: IC sockets though? Why do they pack them in anti-static bags (Digi-Key)! John ;-#)# For the same reason drive through ATMs have instructions in Braille. One kind of something is cheaper to inventory than two kinds of something. If you don't inventory non-static bags, nobody gets sensitive parts in the wrong bags. Now that makes sense. I imagine that the cost of anti-static vs regular bags is minuscule when you buy at Digi-Keys volume. Thanks, John :-#)# |
#39
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Component Damage
On 19.06.2017 22:43, John Robertson wrote:
On 2017/06/16 1:48 PM, Ian Field wrote: Nowadays; suppliers pack *ANY* components in anti-static bags - it used to be some sort of clue which bits to handle with care. There's some unexpected parts on the vulnerable list, so maybe they have a point. molded semiconductors can be subjected to pretty much anything that doesn't break the case. IC sockets though? Why do they pack them in anti-static bags (Digi-Key)! Most likely for compliance reasons. Thanks to the general CYA style over-protectiveness, ESD safety rules are going postal. In various places, rather than using common sense and somewhat educated employees, they don't allow any sort of non-ESD-protected items on the production floors any more. Having the sockets delivered in a non-dissipative plastic bag would have some QC lunatics throw a hissy fit and run screaming because they found something (the bag) that was (allegedly) compromising the ESD safety of the factory |
#40
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Component Damage
On Mon, 19 Jun 2017 16:07:31 -0500, Foxs Mercantile
wrote: For the same reason drive through ATMs have instructions in Braille. Not really. Drive-up ATMs have Braille because it is not uncommon for a blind person to take a cab or have a friend drive them to the bank and use the ATM from the back seat or get out and walk to the drive-up ATM while their friend monitors them for safety. The National Federation of the Blind insisted that ALL ATMs provide a means for use by blind people. |
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