On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote:>John Larkin <jlarkin@highlandtechnology.com> wrote: >> It's probably OK at 15, since I don't expect anybody to stall it, but >> it's weird. We'll get some 24 volt versions to test. > >Toss in a couple of 1N4001s (or surface-mount equal) in series with the >fan connector and get on down the road.But the original board, rev A, first try, works with no kluges. Hacking it would be a sin. https://dl.dropboxusercontent.com/u/53724080/PCBs/P350_SN1.JPG -- John Larkin Highland Technology, Inc picosecond timing laser drivers and controllers jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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Started by ●May 2, 2015
Reply by ●May 10, 20152015-05-10
Reply by ●May 10, 20152015-05-10
John Larkin <jlarkin@highlandtechnology.com> wrote:> On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote: >> John Larkin <jlarkin@highlandtechnology.com> wrote: >> >>> It's probably OK at 15, since I don't expect anybody to stall it, >>> but it's weird. We'll get some 24 volt versions to test. >> >> Toss in a couple of 1N4001s (or surface-mount equal) in series with >> the fan connector and get on down the road. > > But the original board, rev A, first try, works with no kluges. > Hacking it would be a sin.I think that about my code when all the modules are still sitting around version 0.x. Usually, by the time it ships, some modules are up to 1.5 or more. The beauty is still there, but you have to look past the cruft to see it. Stick the diodes in the fan harness? Matt Roberds
Reply by ●May 10, 20152015-05-10
On 5/10/2015 1:19 AM, John Larkin wrote:> On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote: > >> John Larkin <jlarkin@highlandtechnology.com> wrote: >>> It's probably OK at 15, since I don't expect anybody to stall it, but >>> it's weird. We'll get some 24 volt versions to test. >> >> Toss in a couple of 1N4001s (or surface-mount equal) in series with the >> fan connector and get on down the road. > > But the original board, rev A, first try, works with no kluges. > Hacking it would be a sin. > > https://dl.dropboxusercontent.com/u/53724080/PCBs/P350_SN1.JPGCouldn't you get Avnet to change their colour scheme? It clashes horribly. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by ●May 10, 20152015-05-10
On Sun, 10 May 2015 13:02:04 -0400, Phil Hobbs <hobbs@electrooptical.net> wrote:>On 5/10/2015 1:19 AM, John Larkin wrote: >> On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote: >> >>> John Larkin <jlarkin@highlandtechnology.com> wrote: >>>> It's probably OK at 15, since I don't expect anybody to stall it, but >>>> it's weird. We'll get some 24 volt versions to test. >>> >>> Toss in a couple of 1N4001s (or surface-mount equal) in series with the >>> fan connector and get on down the road. >> >> But the original board, rev A, first try, works with no kluges. >> Hacking it would be a sin. >> >> https://dl.dropboxusercontent.com/u/53724080/PCBs/P350_SN1.JPG > >Couldn't you get Avnet to change their colour scheme? It clashes >horribly. ;) > >Cheers > >Phil HobbsThink so? I kind of like it. But then, I have a red car and I'm typing in a red t-shirt. -- John Larkin Highland Technology, Inc picosecond timing laser drivers and controllers jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●May 10, 20152015-05-10
On Sun, 10 May 2015 06:18:04 +0000 (UTC), mroberds@att.net wrote:>John Larkin <jlarkin@highlandtechnology.com> wrote: >> On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote: >>> John Larkin <jlarkin@highlandtechnology.com> wrote: >>> >>>> It's probably OK at 15, since I don't expect anybody to stall it, >>>> but it's weird. We'll get some 24 volt versions to test. >>> >>> Toss in a couple of 1N4001s (or surface-mount equal) in series with >>> the fan connector and get on down the road. >> >> But the original board, rev A, first try, works with no kluges. >> Hacking it would be a sin. > >I think that about my code when all the modules are still sitting around >version 0.x. Usually, by the time it ships, some modules are up to 1.5 >or more. The beauty is still there, but you have to look past the cruft >to see it.Code can be, and often is, edited and recompiled scores, maybe hundreds of times, before people decide that it's good enough, or that it has to ship. Code doesn't have pads that fall off after a dozen reworks. A PC board can't be edited and re-etched in 10 minutes; iterations take more like a month, and are messy and expensive and publically embarassing. Electronic design has to be done right, and brutally checked, at the engineering level, before the Gerbers are formally released and boards ordered and assembled and tested. In general, the easier it is to change something, the less care will go into its design, and the more it will get changed. And the more bugs will never get fixed.> >Stick the diodes in the fan harness?We could, a 3 volt zener or a resistor in a bit of shrink tubing. Or just run a 12 volt fan at 15 volts! That looks like it will work. Our FPGA surface temp is over 100C, and the box quits working at 80 to 85C ambient. We could sell that, but we'd prefer a little more margin. That red uZed board has a couple of holes for mounting a tiny fan above the FPGA. We may do that, as opposed to trying to cool the entire box. -- John Larkin Highland Technology, Inc picosecond timing laser drivers and controllers jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●May 11, 20152015-05-11
On Sun, 10 May 2015 12:14:22 -0700, John Larkin <jlarkin@highlandtechnology.com> wrote:>On Sun, 10 May 2015 06:18:04 +0000 (UTC), mroberds@att.net wrote: > >>John Larkin <jlarkin@highlandtechnology.com> wrote: >>> On Sun, 10 May 2015 04:46:51 +0000 (UTC), mroberds@att.net wrote: >>>> John Larkin <jlarkin@highlandtechnology.com> wrote: >>>> >>>>> It's probably OK at 15, since I don't expect anybody to stall it, >>>>> but it's weird. We'll get some 24 volt versions to test. >>>> >>>> Toss in a couple of 1N4001s (or surface-mount equal) in series with >>>> the fan connector and get on down the road. >>> >>> But the original board, rev A, first try, works with no kluges. >>> Hacking it would be a sin. >> >>I think that about my code when all the modules are still sitting around >>version 0.x. Usually, by the time it ships, some modules are up to 1.5 >>or more. The beauty is still there, but you have to look past the cruft >>to see it. > >Code can be, and often is, edited and recompiled scores, maybe >hundreds of times, before people decide that it's good enough, or that >it has to ship. Code doesn't have pads that fall off after a dozen >reworks. A PC board can't be edited and re-etched in 10 minutes; >iterations take more like a month, and are messy and expensive and >publically embarassing. Electronic design has to be done right, and >brutally checked, at the engineering level, before the Gerbers are >formally released and boards ordered and assembled and tested. > >In general, the easier it is to change something, the less care will >go into its design, and the more it will get changed. And the more >bugs will never get fixed. > > >> >>Stick the diodes in the fan harness? > >We could, a 3 volt zener or a resistor in a bit of shrink tubing. Or >just run a 12 volt fan at 15 volts! That looks like it will work. > >Our FPGA surface temp is over 100C, and the box quits working at 80 to >85C ambient. We could sell that, but we'd prefer a little more margin. > >That red uZed board has a couple of holes for mounting a tiny fan >above the FPGA. We may do that, as opposed to trying to cool the >entire box.This rig lets us run up to 90C ambient. The guy who tested it wimped out there; I'd have cranked up the temp until something failed. https://dl.dropboxusercontent.com/u/53724080/Thermal/FPGA_Fan.JPG There is an on-chip temp sensor in the ZYNQ, but we'd need an FPGA compile and some ARM code to access it, which isn't in the budget just now. Maybe next iteration. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
