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frank <frank@invalid.net>: Sep 07 07:38AM Hi all, has anyone ever seen a VFD (vacuum fluorescent display) failure in which half the display is very dim and the other half looks good? I have this 16 character (16 segments) 1 row display and the first 8-10 characters have a normal brightness, the rightmost ones are very dim, barely readable. I first suspected a problem with the filament supply, but swapping the filament pins has no effect, so I'm a bit puzzled. Waveforms look identical on all the 16 grids too. Unfortunately I have no schematic of this instrument (digelec 824 eeprom programmer), nobody else in the world seems to have this programmer also, so I could not ask anyone for some quick waveform comparison. I'm starting to suspect a bad VFD but I can't imagine how would it fail like this. Part of the filament supply is made with a NE555 that's getting quite hot and also a 120 ohm 1/4W resistor near it gets too hot to touch, but all components I could test looks ok. I swapped the 555 and it doesn't make any change. If I leave the 555 out, the display has no filament supply. Any hint is really welcome. Regards   Frank IZ8DWF

JW <none@dev.null>: Sep 07 05:59AM -0400 On Wed, 7 Sep 2016 07:38:16 +0000 (UTC) frank <frank@invalid.net> wrote in >any change. If I leave the 555 out, the display has no filament supply. >Any hint is really welcome. >Regards   Just a WAG, but perhaps in normal operation the dim digits were constantly lit, while the bright ones weren't?

Tim Schwartz <tim@bristolnj.com>: Sep 06 10:53PM -0400 Hello all,   Can anyone point me to an 'official' table or chart about switch ratings, such as what is the difference between a TV3, TV4 and TV5 marking on the switch?   Many thanks, Tim Schwartz Bristol Electronics

JW <none@dev.null>: Sep 06 02:39PM -0400 http://www.ebay.com/itm/Bulk-Lot-180-pallets-mixed-Server-Pc-Printers-Phone-Home-Electronics-E-Waste-/112122190565?hash=item1a1b00dae5:g:84YAAOSwFe5Xx66f   Think again. This guy better re-think his pricing strategy...

dansabrservices@yahoo.com: Sep 06 11:53AM -0700 At $10,500 per pallet US$, this sounds extremely expensive!!   If this was in the US, the most I would pay (including shipping) would be $1000 per pallet. Even that is a major risk without knowing the actual contents. You can buy store returns for around $1500 per pallet. At least there, you have an idea of the contents and the status of the units.   I think, I'll pass on this one. Dan

"pfjw@aol.com" <pfjw@aol.com>: Sep 06 11:54AM -0700 On Tuesday, September 6, 2016 at 2:39:11 PM UTC-4, JW wrote: > http://www.ebay.com/itm/Bulk-Lot-180-pallets-mixed-Server-Pc-Printers-Phone-Home-Electronics-E-Waste-/112122190565?hash=item1a1b00dae5:g:84YAAOSwFe5Xx66f   > Think again. > This guy better re-think his pricing strategy...   I would expect him to pay me at least AU$880,000 to take it away. Comes to only about AU$2/pound or AU4.40/kg.   Peter Wieck Melrose Park, PA

Don Y <blockedofcourse@foo.invalid>: Sep 06 01:03PM -0700 On 9/6/2016 11:39 AM, JW wrote: > http://www.ebay.com/itm/Bulk-Lot-180-pallets-mixed-Server-Pc-Printers-Phone-Home-Electronics-E-Waste-/112122190565?hash=item1a1b00dae5:g:84YAAOSwFe5Xx66f   > Think again. > This guy better re-think his pricing strategy...   "I started collecting buying selling fixing many years ago as a hobby..."   "My Home, Garage, four sheds, Carport, Driveway, front and back yard is full of stuff"   ...and it hasn't RAINED on ANY of this kit in ALL that time?   [Do they have pack rats (rodents) in Oz?]   A "scrap" PC -- unless it is something "precious" -- is worth about $10-20. A pallet of PC's is worth maybe $500 (?). A pallet of (reasonably new -- then how did HE come by them?) servers might be worth twice that -- assuming it is a *full* pallet (~4'x4'x4')   Have a gander at what stuff goes for here, in bulk:   <https://uaauctions.arizona.edu/>   I'd be tempted to add up the prices of ALL the lots for one of the "past auctions" to see what a "warehouse full of stuff" sells for... (but, I have more interesting things to do!)

JW <none@dev.null>: Sep 06 04:37PM -0400 On Tue, 06 Sep 2016 13:03:06 -0700 Don Y <blockedofcourse@foo.invalid>   >"My Home, Garage, four sheds, Carport, Driveway, front and back yard >is full of stuff"   >...and it hasn't RAINED on ANY of this kit in ALL that time?   By the looks of some of the stuff, yes!   >[Do they have pack rats (rodents) in Oz?]   I get the feeling his wife probably left him. Hence the need for a new house.

Ignoramus32044 <ignoramus32044@NOSPAM.32044.invalid>: Sep 06 05:06PM -0500 > http://www.ebay.com/itm/Bulk-Lot-180-pallets-mixed-Server-Pc-Printers-Phone-Home-Electronics-E-Waste-/112122190565?hash=item1a1b00dae5:g:84YAAOSwFe5Xx66f   > Think again. > This guy better re-think his pricing strategy...   He wants $13,888 per pallet of e-waste.   I would say he needs to find better medications...   i

Tom Gardner <spamjunk@blueyonder.co.uk>: Sep 07 12:02AM +0100 On 06/09/16 23:06, Ignoramus32044 wrote:   >> Think again. >> This guy better re-think his pricing strategy...   > He wants $13,888 per pallet of e-waste.   A perfectly reasonable "want", probably derived from "I need X, I have Y, therefore I want X/Y for each Y". All very logical, if unrealistic.   I'm cautious about making fun of someone with unknown circumstances and problems. "There but for the grace of god go I", and all that.

M Philbrook <jamie_ka1lpa@charter.net>: Sep 06 07:32PM -0400 In article <173usb1duhcb1ndb68s87mgsg15epotcs2@4ax.com>, none@dev.null says...   > http://www.ebay.com/itm/Bulk-Lot-180-pallets-mixed-Server-Pc-Printers-Phone-Home-Electronics-E-Waste-/112122190565?hash=item1a1b00dae5:g:84YAAOSwFe5Xx66f   > Think again. > This guy better re-think his pricing strategy...   it's a smorgasboard!!!   Jamie

Don Y <blockedofcourse@foo.invalid>: Sep 06 05:16PM -0700 On 9/6/2016 1:37 PM, JW wrote: >> [Do they have pack rats (rodents) in Oz?]   > I get the feeling his wife probably left him. Hence the need for a new > house.   I've got a fair bit of kit -- stashed in various (creative!) places around the house. But, with few exceptions, it's all "serviceable" or "in use" -- not piles of untested cruft that I'd *hoped* to do something with (e.g., SELL!), "someday". Test equipment purchased over the years for various "one-off" jobs, prototypes, patent-proofs, etc. Plus all sorts of "supplies" (you'd consider a box of spare DVD-R/W's "supplies", wouldn't you? Likewise, a box of SCSI cables, another box of patch cords, etc.? :> )   SWMBO grumbles, pretty regularly. But, perhaps EQUALLY regularly, she needs some-thing for some-reason and I deliver a-thing that will satisfy that-need, in a matter of minutes!   Whew! Another week with THAT "talk" averted!

ohger1s@gmail.com: Sep 06 07:01PM -0700 On Tuesday, September 6, 2016 at 6:06:17 PM UTC-4, Ignoramus32044 wrote:   > He wants $13,888 per pallet of e-waste.   > I would say he needs to find better medications...   > i   Not just e-waste, but also sewing machines, mowers, sinks, etc. For two and a half million you can turn your home and land into this man's toilet...   Which reminds me of a Jeff Foxworthy quote: "Why do rednecks always have a lawnmower but never have a lawn?"

Micky <NONONObobbyburns1111@gmail.com>: Sep 06 12:52PM -0400 On Sun, 04 Sep 2016 09:35:22 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   > "...with a 'less expensive' power supply and 'less expensive' LCD." >I would assume that implies that the rest of the electronics are the >same in both versions.   "Unfortunately, Hantek does not distinguish between their products by using different part numbers. However, when we order Hantek oscilloscopes, we always specify that they are to supply us with the upgraded versions."   I've been doing that for a long time.   At a restaurant, I always tell them I want prime grade beef.   When I buy a car, I tell the salesman, Give me a good one.   And at restaurants I always say that I want a clean glass.   I wonder if this method works.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 06 02:16PM -0400 In article <3pstsb5ginpn8q49h0ti8suk92kbrv56m2@4ax.com>, NONONObobbyburns1111@gmail.com says... > using different part numbers. However, when we order Hantek > oscilloscopes, we always specify that they are to supply us with the > upgraded versions."   Hantek does seem to have an INT or International after the part number on some of their scopes. This is suspose to be the upgraded parts if the advertisment is correct. I have not seen any scopes in person,so do not know if all of them inported to the US are that way or not, or if they even make any at all that do not have that International after the part number.   As just a hobby user I can not justify an expensive scope,but did put a DSO 5202P on order today from Circuit Specilies. This will be my first storage scope. The one that I have been using is a Tectronics 465b 100 mhz analog scope. Just thought a storage scope wold be nice to play with for around $ 300.

Jeff Liebermann <jeffl@cruzio.com>: Sep 06 11:44AM -0700 On Tue, 6 Sep 2016 14:16:24 -0400, Ralph Mowery   >As just a hobby user I can not justify an expensive scope,but did put a >DSO 5202P on order today from Circuit Specilies.   Argh, too late. You could have bought the cheaper Hantek model, which can be hacked to provide 200MHz bandwidth and additional features: <http://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg264085/#msg264085> <http://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/>   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"pfjw@aol.com" <pfjw@aol.com>: Sep 06 11:48AM -0700 On Sunday, September 4, 2016 at 11:37:26 AM UTC-4, Ralph Mowery wrote: > There is a lot of items comming from China now. Some seems ok and some > not.   I have never felt either the need or the inclination to purchase any electronics from China for my hobby, or on which I might depend. Full stop.   Peter Wieck Melrose Park, PA

JW <none@dev.null>: Sep 06 03:47PM -0400 On Tue, 6 Sep 2016 11:48:06 -0700 (PDT) "pfjw@aol.com" <pfjw@aol.com> wrote in Message id: >> not.   >I have never felt either the need or the inclination to purchase any electronics >from China for my hobby, or on which I might depend. Full stop.   I got to say +1 on that, but I make my living with such gear. I'll only trust equipment from first tier T&M manufacturers. Tek, Keysight/Agilent/HP, Keithley, Fluke, etc. Don't have time for the bugs.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 06 04:53PM -0400 In article <5c3usb11rmm66cako0cnpevgubet8s2g6r@4ax.com>, jeffl@cruzio.com says... > can be hacked to provide 200MHz bandwidth and additional features: > <http://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg264085/#msg264085> > <http://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/>     I have either seen that or something similar. Sometimes the components may not be up to the faster speed in the slower scopes. I did see one place where one of the scopes needed a capacitor changed or removed.   Can't prove it, but just thinking that they may do the chips like the old compuer chips. They would test them for speed and mark them for the maximum speed they could run without making errors.     I did buy a function generator a while back that went to 25 MHz with the sine waves. The faster square waves did not look too good but there was a modification to change about 10 parts to bring the waveform more up to speed.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 06 05:03PM -0400 In article <q27usbl6n0ldsnvir2uruljkgphidgrkuu@4ax.com>, none@dev.null says...   > I got to say +1 on that, but I make my living with such gear. I'll only > trust equipment from first tier T&M manufacturers. Tek, > Keysight/Agilent/HP, Keithley, Fluke, etc. Don't have time for the bugs.   If I made my living I would have the high quality equipment. I did work as an instrument technician for a large company and we bought the beter quality test equipment and much of it was calibrated by a lab that certified it to the NIST, or what ever it is called every year or so.   I do have some older HP and Tectronic and Fluke test equipment. It is just hard to justify paying several thousand dollars when $ 300 will tell me all or more than I need to know.   I look at it like the Harbor Freigh stuff. For something that may be used just a few times, much of that will get the job done. Say a hammer. They may use soft metel and the hammer will mushroom after a few hits, but if all yo want to do with it is drive in a few tent posts a couple of times a year it is worth it just to have that hammer in the box with the tent.

Jeff Liebermann <jeffl@cruzio.com>: Sep 06 04:47PM -0700 On Tue, 6 Sep 2016 16:53:28 -0400, Ralph Mowery   >Can't prove it, but just thinking that they may do the chips like the >old compuer chips. They would test them for speed and mark them for the >maximum speed they could run without making errors.   Nope. What they do is build them all to 200 MHz, and then reduce the bandwidth and remove features to accommodate those that don't want to spend as much money. I only know of one scope that has been modified in this manner. It was a Rigol something and it worked perfectly. Anyway, the EEVBLOG thread is rather long and has 2834 replies over the last 6 years. If there were any problems encountered doing the modification, I'm sure they would have appeared somewhere in the thread. I didn't read all 2834 replies, but in skimming, I found a few where some of the features didn't quite work as expected, but except for one person who had problems using decent parts, the reports were generally positive.   Too late to change your order?   >sine waves. The faster square waves did not look too good but there was >a modification to change about 10 parts to bring the waveform more up >to speed.   The square wave has all the odd order harmonics of the fundamental sine wave. Much depends on the corner frequency of the output low pass filter. In general, the filter will need to pass everything up to the 5th or 7th harmonic to looks like a square wave. In a function generator, the low pass is not really necessary, but helps if there is some digital junk that might leak into the output amplifier. It might also be there to keep the FCC happy, but since I've never type certified a function generator, I don't know if that's really necessary.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Paul <nospam@needed.invalid>: Sep 06 01:09PM -0400 Mr. Man-wai Chang wrote:   >> That was my point.   > Most mortals don't know what lithium is and how it behaves. Mind to > summarize? :)   It behaves badly and its parents have it on a strict 10PM curfew.   https://en.wikipedia.org/wiki/Lithium   The Alkali Metals: Reaction of Lithium with the air (Flash Video)   http://www.rsc.org/learn-chemistry/resource/res00001248/the-alkali-metals-part-1?cmpid=CMP00002458#!cmpid=CMP00002467   Paul

Tekkie® <Tekkie@comcast.net>: Sep 06 05:27PM -0400 Paul posted for all of us...     > The Alkali Metals: Reaction of Lithium with the air (Flash Video)   Clever little word there (stupid mind can't come up with the correct term.)   -- Tekkie

"James Wilkinson" <invalid@something.com>: Sep 06 10:31PM +0100 > Common causes   > There have only been 35 cases of the Galaxy Note 7 catching fire > reported worldwide following 2.5 million sales, Samsung says.   35 / 2.5 million = very small number.   -- Windows 95: n. 32 bit extensions and a graphical shell for a 16 bit patch to an 8 bit operating system originally coded for a 4 bit microprocessor, written by a 2 bit company, that can't stand 1 bit of competition.

mattzelazny@gmail.com: Sep 06 01:50PM -0700 > which has a very good circuit description that should allow you to > troubleshoot the problem.   > Arfa   Arfa,   I have the same issue with a wave radio. Can you hook me up with schematic as well??   thanks,   Matt

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