Benchmark idea presented at the bottom between stars (***** *****) Lots of counterfeit capacitors out there. Some [mostly] Chinese companies stole the formula for the electrolyte and started making their own capacitors; of course they did it wrong (process, etc) and produced these capacitors that have been plaguing a surprising percentage of products on the market today.
The engineers who design products don't usually specify the brand; that is left up to the company or division that is responsible for actually mass producing the parts. To cut costs and maximize profits, the cheapest parts that meet the spec. are selected. These bad caps are often fine at first, but after a few months or years of service, or so many hours of use, they electrolyte breaks down and the tops bulge, the plates are distorted, and the specification of the capacitor changes, often greatly. What's unfortunate, is that different production runs or batches of the same hardware part can end up with different brands of capacitors. So even in Neil's computer, the motherboard, or power supply or any of the components, could have bad capacitors, if they are not inspected before put into service. My friends and I have pulled from our university's trash, tons of motherboards and power supplies and other equipment, measured the physical sizes of all of the capacitors, and ordered replacements, a few hours with a soldering station and we have working equipment again. All for a few dollars spent at mouser or digikey. Here is a list of some brands known to produce problematic capacitors. http://www.badcaps.net/forum/showthread.php?t=388 If you are buying caps from mouser, digikey etc you will probably never encounter these brands. I think this whole 'special computer' thing is a bit overblown. Some good points have been raised though. The type of computer needed for SDR is not that of your typical consumer PC. Best performance will not be achieved on a machine with a million bells and whistles on the mother board, (turning these off in the bios may help in some situations) A workstation type of computer is probably more appropriate. What about laptops? The Flex-3000 is advertised to be a companion to a laptop computer. There are a lot less options for laptops. If the Flex will not work properly on the average modern (Dell, Gateway, whatever) computer, then this is a problem that should be smoothed out by the Flex/PowerSDR developers. I believe it is the goals and intentions of Flex to produce a product that is compatible the majority of computers out there. For those willing and able to spend extra, and get a Flex-C, or a custom computer (build by themselves or some company willing to work with them) then they can have a system that works a bit better than the off the shelf alternatives that are more practical for many users. ***** What I think PowerSDR/Flex needs is a benchmark utility that measures the parameters and performance of the sub-systems that matter. Things like latency etc. come to mind. This way, Neil can build a computer, he has a way of advertising the performance. Or I could build my own computer, and see how well it works, do some tweaking, and see if I have changed things for the better. I also could check to see if new drivers are affecting the system. Or someone could buy a Dell, and do the same. Using a benchmarking utility we have a way to compare and share with each other what works. This way we can make educated recommendations to help everyone settle on an appropriate system that fits their needs, their budgets, and their shack. ***** -Greg, N2GZ --- Bad caps caused problems across a range of products. http://www.badcaps.net/ Mel, k0pfx --- Thanks Don, 1st I've heard of it. Will keep an eye out for that problem. Another good reason to try Neal's pre-configured approach Brian --- Don wrote: Be careful with the 8400 as this was one of a number of PCs from Dell that experienced the capacitor failure - where the top of the cap pushed up and was no longer flat. apparently they were using a bad batch of caps on their motherboards. I had two of the 8400s and I just recently trashed them both as the motherboards failed. Up to about 1.5 years ago Dell was providing replacement motherboards regardless of whether the pc was in warranty or not. They have since discontinued that service. Don - kx9q _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
