MsPacMan
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From: krw on 18 Jul 2010 21:05 On Sun, 18 Jul 2010 21:00:44 -0400, Phil Hobbs <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >krw(a)att.bizzzzzzzzzzzz wrote: >> On Sun, 18 Jul 2010 20:38:30 -0400, Phil Hobbs >> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >> >>> On 7/18/2010 4:42 PM, Joerg wrote: >>>> krw(a)att.bizzzzzzzzzzzz wrote: >>>>> On Sun, 18 Jul 2010 09:52:00 -0700, Joerg<invalid(a)invalid.invalid> wrote: >> <snip> >> >>>>>> Mostly that will result in a complete redesign. That is when the NRE >>>>>> that entails must be factored in, to see how fast the effort truly >>>>>> amortizes. Anything north of four years is generally frowned upon. >>>>> Yep. I'm doing a redesign now, but at least on this pass the ground rules >>>>> state that no firmware can be changed. That alone cuts the possibilities some >>>>> 80% (I've already done the design, including firmware changes). The real >>>>> bigies would hit the case, though. There is well into six figures in the >>>>> molds so there is no way that's going to pay. >>>>> >>>> That would put enclosure changes off-limits, unless you make a bazillion >>>> of these per year. I've often run into this "no SW change" or "no >>>> firmware change" requirement and never really understood it. There are >>>> nowadays so many trick you can play in firmware that save beaucoup bucks >>>> because whole chunks of hardware could simply vanish. >>>> >>> Depends whether the original firmware guy is still there, >>> though...often, getting somebody to change somebody else's working >>> firmware is a complete can of worms. >> >> The lead programmer is still around. Actually, they all are with the >> exception of the guy who went to the FBI. Chasing terrorists was more fun, >> evidently. >> >>> OTOH, since you can still make the previous version, at least there's a >>> revenue stream paying for all that mucking about. >> >> It's an opportunity cost issue. That's above my pay grade. I give them the >> numbers and they tell me what to work on. Well, I gave them the numbers nine >> months ago... > >Being on my own, and working mainly with startups, I can assure you that >opportunity cost is a much nicer thing to worry about than cash flow! I understand. Before we got the TI DSP boat right-side-up there was no cash flow. The owner isn't wanting to go back there, for some reason. He now has a choice, save tens of buck per copy or make something new. The only advantage I see of doing yet another redesign is that he doesn't have to actually build anything (more) to put that money in his pocket. The engineering costs are fixed.
From: Mark Zenier on 18 Jul 2010 14:07 In article <aml346p9blsmkbe9p1o5bsgsh2l2gbu8ks(a)4ax.com>, krw(a)att.bizzzzzzzzzzzz <krw(a)att.bizzzzzzzzzzzz> wrote: >There once were connectors that would accept a scope tip. Has anyone seen >those recently? They were *expensive* but for test jigs they would be useful. I scored a few of them from the shop inventory on a job I had back in the early 1980s. The company on the packaging was "Specialty Connector Corp.". Last I searched for them, it looked like their corporate sucessor only did pricey microwave stuff. Mark Zenier mzenier(a)eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)
From: JosephKK on 20 Jul 2010 01:51 On Fri, 16 Jul 2010 12:18:33 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >On Fri, 16 Jul 2010 10:29:43 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>This is cool, a nanograbber for clipping onto fine-pitch parts. >> >>ftp://jjlarkin.lmi.net/MsPacMan.JPG >> >>As you squeeze it to open the little wire clamp things, it looks just >>like the PacMan thing gobbling up dots. Flip the image over, and it >>looks like some fancy Israeli assault rifle. These cost $14 each, by >>the dozen. >> >>But to be serious for a second: We seed our boards with "test points", >>really just unmasked vias with 42 mill drills, a nice size to jam a >>scope probe tip into. What I really need is a thing that I can solder >>to the end of a wire, like a scope ground clip or a test lead, that >>will plug into such a hole and stay put and make contact. It would be >>a little metal tube with a bustle of curved, springy wires, 2 or more, >>poking out the end... >> >> springy wires jam into via >> tube >> =========== /------\ >> wire ----- \ >>===================== >> -----\ / >> =========== ------- >> >> >>Google's no help. Does anybody know if someone makes these things? >> >>John > >I vaguely remember, from my GenRad days, "pogo" pin ?? > > ...Jim Thompson Well known from bed of nails testers. You would kind of need to convert the scope probe to use one, not pretty.
From: JosephKK on 20 Jul 2010 02:02 On Sat, 17 Jul 2010 06:02:00 +0200, Frank Buss <fb(a)frank-buss.de> wrote: >Joerg wrote: > >> I believe Newark carries them. > >Digikey has it, too. Search for "keystone test points" and you'll get a >nice selection for diameter, color etc. Looks like it is popular, because >some types are available in container quantities :-) > >http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=5002K-ND By the container? Let's see, about 5000 on a 7 inch tape reel. A container is about 500,000,000? Sorry, my 'rithmetic is crashing on me.
From: JosephKK on 20 Jul 2010 02:05
On Sat, 17 Jul 2010 09:38:50 -0700, Joerg <invalid(a)invalid.invalid> wrote: >krw(a)att.bizzzzzzzzzzzz wrote: >> On Sat, 17 Jul 2010 09:11:49 -0700, Joerg <invalid(a)invalid.invalid> wrote: >> >>> krw(a)att.bizzzzzzzzzzzz wrote: >>>> On Sat, 17 Jul 2010 06:33:23 -0700, Joerg <invalid(a)invalid.invalid> wrote: >>>> >>>>> Frank Buss wrote: >>>>>> Joerg wrote: >>>>>> >>>>>>> I believe Newark carries them. >>>>>> Digikey has it, too. Search for "keystone test points" and you'll get a >>>>>> nice selection for diameter, color etc. Looks like it is popular, because >>>>>> some types are available in container quantities :-) >>>>>> >>>>>> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=5002K-ND >>>>>> >>>>> Thanks, I didn't know they carried these. Unfortunately such test points >>>>> are comparatively large, for 0.040" holes and similar. >>>> Come on Joerg. They're only three for ten bucks. You can afford them! >>>> >>>> <yikes!> BTW, we use something similar for less than $.10 each. ...and those >>>> are usually deleted when production settles down. >>> >>> I didn't say I can't afford them :-) >> >> ;-) >> >>> They are just a bit large for modern SMT layouts. Technologically a bit >>> long in the tooth. >> >> We use them on power supplies and a couple of communications lines (RS-422). >> They're useful for scope grounds. >> >> There once were connectors that would accept a scope tip. Has anyone seen >> those recently? They were *expensive* but for test jigs they would be useful. > > >Not recently. I often use needles, the ones that come with higher end >shirts. You know, where Murphy says that you'll always forget one when >trying it on and ... OUCH. Many can be soldered to (not all) and then >occasionally I use a rubber band to tug a bit on the cable or the needle >so it won't fly out. > >The needles are free, as long as you pay the $49 plus tax for the shirt :-) That is a mildly pricey shirt. I generally get shirts for $20 each or less. |