Must cut 40mm hole in 1/4" aluminum bar

If they are the cluster closest to the CPU, you should replace all of them. The remaining old caps will continue to go up in ESR, and generate internal heat until they fail. I replace a lot of bad caps. :(

Windows 10 may be "designed for touch screen and cell phone" but it is a pretty kick-ass desktop OS as well. I was a XP man. Perhaps the solidest MS OS ever by the time SP3 had rolled out - then the Win7 and Win8 abortions came along. Win10 brought back the reliability and functionality of XP, in my opinion. It's different than XP, but I actually - after a short time, found it to be an even better desktop OS.

Unless I had an app that would NOT run on 10, or specialized equipment that wouldn't talk to 10, there's no way I'd go back to 7 or XP.

I was never an apple person - but given a choice of IOS or Android -

- - I bought an older I-Phone (SE) I have an android tablet I don't use, and got a Win10 convertible tablet for the wife. I'd have stayed with my old BB10 phone but it doesn't talk to my hearing aids - the fruit-phone does.

If they are the cluster closest to the CPU, you should replace all of them. The remaining old caps will continue to go up in ESR, and generate internal heat until they fail. I replace a lot of bad caps. :(

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Electrolytics didn't used to go bad like that. My stock of beer-can-sized ones from the 80's which I occasionally reform leak less than 1mA after a few minutes connected to a (vacuum tube) power supply set to their working voltage and 15mA.

There was a rumor that the bad ones originated when an Asian manufacturer stole an intentionally leaked faulty formula.

Windows 10 may be "designed for touch screen and cell phone" but it is a pretty kick-ass desktop OS as well. I was a XP man. Perhaps the solidest MS OS ever by the time SP3 had rolled out - then the Win7 and Win8 abortions came along. Win10 brought back the reliability and functionality of XP, in my opinion. It's different than XP, but I actually - after a short time, found it to be an even better desktop OS.

Unless I had an app that would NOT run on 10, or specialized equipment that wouldn't talk to 10, there's no way I'd go back to 7 or XP.

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My policy is to assign risky tasks to the least valuable computer that can handle them. My Win 10 laptop goes online for updates but not general browsing.

Some of the performance improvement over W7 is due to having an i5 CPU instead of a Core 2 Duo although the clock speeds aren't much different, 2.4 and 2.8 GHz.

I've worked on boards with 18 layers. You need the right rework tools to prevent damage on those. Most people don't use a hot enough desoldering iron, so it weakens the board's hold on the plated through vias. It's no fun having yo scrap a new board that cost over $8,00 to build.

If you use a vacuum desoldering iron and you don't get all of the solder the first try, use some 63/37 solder to replace what you removed. Then try again. You need that solder to transfer the heat to the bottom of the via. Another thing to watch. Often the lead is stuck to the wall of the via after the solder is removed. touch the lead with a hot soldering iron and push i away from the wall. Wait a second o two for the plating to cool, the remove the iron. I as NASA rated for soldering when I worked at Microdyne, and I repaired a lot of the old Commodore C64 computer boards. I had to teach the assemblers at Cincinnati Electronics how to solder the tabs of a small audio transformer to a circuit board at the rework station. The soldering irons weren't hot enough to melt the old solder to remove the transformer after their leads were cleared. I showed them how to use two irons and their wet wicking to remove it, and to heat the tab to bend it away from the plated through slot. Soldering was a union job. I worked in QA, so I had a very angry union steward glaring at me as I worked. They had two boards with that problem, so I looked her in the face and said, "Watch closely, I'm only going to do This one more time!"

She had got in my face my first day there, to inform me that 'No man has ever been able to solder anything!" I told here that I had a business during the daytime, and that I used up to a half pound a mont. Her jaw dropped. :)

Those capacitors weren't used in high frequency applications, and they didn't pass as much current. Some CPU ICs operate at 1.8V at up to 100 amps. All the ripple is passed to the ground plane as those capacitors filter the rail. Multiple capacitors in parallel are used for several reasons. They are smaller, so each one generates less heat. A cluster of them have a mower ESR than a single capacitor. They can be a lot closer to the CPU to improve voltage regulations, and reduce the radiated noise.

That was around 1999 and they failed while the computers were under warranty. I had it happen to a two month old Compaq computer. I contacted them. I was told to drop it off at the closest Radio Shack, and it would be serviced at their service center in Orlando. Then they said, "Back up all of your files, because they will reformat and install the operating system. I told them that it was dead, and I couldn't back it up without removing the drive. That would beak the security seal and void the warranty. I told them that I was gong to remove the drive, and never buy another of their products.

Those capacitors weren't used in high frequency applications, and they didn't pass as much current. Some CPU ICs operate at 1.8V at up to 100 amps. All the ripple is passed to the ground plane as those capacitors filter the rail. Multiple capacitors in parallel are used for several reasons. They are smaller, so each one generates less heat. A cluster of them have a mower ESR than a single capacitor. They can be a lot closer to the CPU to improve voltage regulations, and reduce the radiated noise.... ==============================

On one-off military and FAA digital radio prototypes where GHz-range performance was more important than production cost I used tantalums for distributed bulk capacitance and 0.01uF paralleled with 0603 or 0402 1nF MLC chip caps, typically on the bottom of the board under the device, as close to the power vias as possible, and sometimes overlapping them which I could get away with since I soldered everything myself. We based this on network analyzer sweeps of the capacitors and graphs like these:

Those caps took a long time to work themselves out of the supply chain and lots of them managed to get through warranty. I had quite a few where the computers had to go back for warranty where I asked for permission to pull the drive and noted the permission on the RMA form.

Not buying another Compaq / Pakard Bell / HP computer definitely was not a BAD decision. Some of their (HP) printers are / were pretty decent but Canon and Lexmark have sure eaten their lunch over the last

Most of the time, I'm sitting in front of a high-end i7 machine with 64G of ram running Windows 10. I have VMWare virtual machines with various operating systems for doing tests and developing inter-computer applications. One of the VMs is specifically for doing the more "dangerous" tasks. This PC has a 55" quad definition monitor attached, so all those vm processes have healthy sized windows to run in - a single 55" is equivalent to four 26" screens.

On the list of things to get is an optically isolated USB cable - I ONCE made a nasty mistake and let some smoke out of my laptop while connected to a large machine I was repairing. Somehow, the USB port on the laptop was not 480V compliant ;->

---- As for desoldering, I have a Pace MBT which makes plenty of heat for through holes and an Aoyue hot-air rework station. For particularly stubborn through-hole parts or for multi-sided surface mount parts, Chipquik makes a very low melting point alloy that you can add to the joint making it much easier to melt

That was my first thought.

I recently needed to replace my shop laser printer (really old Brother) and took a chance on a Pantum M7102DW. Though I had never heard of the company, this gives me scanning with autofeeder and double-sided b&w printing for a whopping $119 (delivered) from Amazon. I have absolutely no complaints, and bought another for a customer.

By way of comparison, my first laser printer was an HP Laserjet III which cost $1600.

Most of the time, I'm sitting in front of a high-end i7 machine with 64G of ram running Windows 10. I have VMWare virtual machines with various operating systems for doing tests and developing inter-computer applications. One of the VMs is specifically for doing the more "dangerous" tasks. This PC has a 55" quad definition monitor attached, so all those vm processes have healthy sized windows to run in - a single 55" is equivalent to four 26" screens.

Nice! I no longer have or need anything nearly that powerful, but this aged monitor and laptop collection does measure 45" diagonally and is separately showing live TV news, the 7 day forecast, your post and this reply.

I recently needed to replace my shop laser printer (really old Brother) and took a chance on a Pantum M7102DW. Though I had never heard of the company, this gives me scanning with autofeeder and double-sided b&w printing for a whopping $119 (delivered) from Amazon. I have absolutely no complaints, and bought another for a customer.

By way of comparison, my first laser printer was an HP Laserjet III which cost $1600.

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My HP6110 cost nothing, because it didn't work until I cleaned the fogged front surface mirror with no-residue automotive MAF sensor cleaner. The repair manual's procedure for that problem is to trash it and buy something better. My sister unloads such dead office stuff from her clients on me when they can't easily get rid of it otherwise. Usually it's better than anything I have, and easily fixed.

Any cheap CNC machines that will cut through 1/4" 6061 aluminum?

Was looking at "generic" (a.k.a. the Chinese "brand") CNC machines recently. Says they will cut PVC. That is potentially useful.

The early HP laser printers were workhorses. I am currently using a Samsung networked printer tat prints on both sides.

I have a junk HP color all in one with a total of 24 pages printed before it stopped feeding paper. What a waste, for whoever bought it new. I picked it up with a pile of junk computers.

Any cheap CNC machines that will cut through 1/4" 6061 aluminum?

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Why CNC? Slide rules, paper drawings and manual machine tools got us to the Moon.

You're kind of a pack rat hoarder of worthless s*it like Wieber, aren't you?

A spaceship got us to the moon.