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Allodoxaphobia <trepidation@example.net>: Jan 19 06:09PM On Sun, 19 Jan 2020 10:08:04 -0500, Ralph Mowery wrote: > that some buttons are sewen on with will work.   > Where I worked making polyester sandoze was added to the material to > make the whites even whiter. That glows under UV light.   Cat piss. Cat piss shows up quite bright under UV light.   Glad to help, Jonesy -- Marvin L Jones | Marvin | W3DHJ.net | linux 38.238N 104.547W | @ jonz.net | Jonesy | FreeBSD * Killfiling google & XXXXbanter.com: jonz.net/ng.htm

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 02:17PM -0800 On Sat, 18 Jan 2020 16:11:01 -0500, KC JONES <kcharlie@nowhere.net> wrote:   >years, but recently brought it out to sterilize a room where a person >had been sick. However, I don't know if it still emits the germ killing >UVC spectrum. What's a quick way I could tell for sure? Thanks.   Ummm... perhaps a UV-C light meter? Something like this: <https://www.solarmeter.com/uvc-meters.html> <https://youtu.be/6Jaic8OwzaU> Response is 246-262 nm with a UV-C pass filter.   More of the same: <https://www.ebay.com/sch/i.html?_nkw=uvc+light+meter> Typically $350 to $1,100. You might want to look into borrowing or renting such a meter.       -- 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

Ralph Mowery <rmowery28146@earthlink.net>: Jan 19 07:01PM -0500 In article <04k92fhqd6l2ekn8gdfbhjqq3cug1r31cp@4ax.com>, jeffl@cruzio.com says... > <https://www.ebay.com/sch/i.html?_nkw=uvc+light+meter> > Typically $350 to $1,100. You might want to look into borrowing or > renting such a meter.   You would think that China would have some for way under $50 . While they may not work the best, China seems to have almost every thing else very inexpensive.   Bad to pay $ 300 + to check out a $ 20 or so light.

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 04:47PM -0800 On Sun, 19 Jan 2020 19:01:47 -0500, Ralph Mowery >they may not work the best, China seems to have almost every thing else >very inexpensive.   >Bad to pay $ 300 + to check out a $ 20 or so light.   I couldn't find anything from China that is substantially cheaper: <https://www.aliexpress.com/wholesale?trafficChannel=main&d=y&SearchText=uvc+meter<ype=wholesale&SortType=price_asc&groupsort=1&CatId=0&page=1>   The bulk of the cost seems to be in the sensor and the UV-C filter. <https://www.aliexpress.com/item/32998762871.html> <https://www.edmundoptics.com/c/optical-filters/610/#27587=27587_d%3A%5B200.00%20TO%20280.00%5D&ProductFamilies_ii=ProductFamilies_ii%3AMTQ5NjM1>   -- 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

whit3rd <whit3rd@gmail.com>: Jan 19 07:09PM -0800 On Sunday, January 19, 2020 at 2:18:04 PM UTC-8, Jeff Liebermann wrote:   > Ummm... perhaps a UV-C light meter? > Typically $350 to $1,100. You might want to look into borrowing or > renting such a meter.   It'll embrittle plastic quick if it's really UV-C; a disposable bag turning to dust would convince me it was shining. Or, you could imagine something with a slit, telescope mirror, thermopile, and grating, if intensity measurement was important.   I'd think of something quick-and-dirty before shelling out bucks.

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 20 05:39AM -0800 Not so long ago, someone here stated that this group exists to teach gullible individuals how to do things the hard way (as opposed to the correct way, or the effective way. Emphatically not the 'easy way').   This thread is a very nearly perfect example of that process.   a) Whereas light on the correct UV spectrum *will* kill many (not all) microbes and such, it is not designed against the stated purpose. As an Ozonator in a water sterilization device, fine. Or in a fume-hood.   NOTE FROM SECONDARY SOURCE: Germicidal lamps emit radiation in the UV-C portion of the ultraviolet (UV) spectrum, which includes wavelengths between 100 and 280 nanometers (nm). The lamps are used in a variety of applications where disinfection is the primary concern, including air and water purification, food and beverage protection, and sterilization of sensitive tools such as medical instruments. Germicidal light destroys the ability of bacteria, viruses, and other pathogens to multiply by deactivating their reproductive capabilities. The average bacteria may be killed in 10 seconds at a distance of 6 inches from the lamp.   b) That form of UVR that is effective in killing pathogens will also damage humans.   NOTE FROM SECONDARY SOURCE: UVR is not felt immediately; in fact, the user may not realize the danger until after the exposure has caused damage. Symptoms typically occur 4 to 24 hours after exposure. The effects on skin are of two types: acute and chronic. Acute effects appear within a few hours of exposure, while chronic effects are long-lasting and cumulative and may not appear for years. An acute effect of UVR is redness of the skin called erythema (similar to sunburn). Chronic effects include accelerated skin aging and skin cancer. UVR is absorbed in the outer layers of the eye – the cornea and conjunctiva. Acute overexposure leads to a painful temporary inflammation, mainly of the cornea, known as photokeratitis. Subsequent overexposure to the UV is unlikely because of the pain involved. Chronic exposure leads to an increased risk of certain types of ocular cataracts. Working unprotected for even a few minutes can cause injury. It is possible to calculate the threshold for acute effects and to set exposure limits. It is not possible, however, to calculate threshold for chronic effects; therefore, because no exposure level is safe, exposure should be reduced as much as possible.   c) If one takes the 30 seconds or so to research how UV light is used in laboratory settings to sterilize equipment, surfaces and instruments, one will see that, again, it is not indicated for the purpose stated hear.   Bottom line: UV light is not indicated. UV light is dangerous. UV light is not 'quick' either. To do what is required per the OP is good old 'asses and elbows' work, not the waving of a magic wand or, pun intended, light saber.   Put another way: There are two issues here: #1 is the sterilizing of a sick-room after the fact. For which UV light is neither safe nor effective. #2 is to determine if any given UV lamp is still emitting over the target frequency(ies). And that may be had right off the shelf, cheap:   https://www.teachersource.com/product/1099/light-ultraviolet?gclid=Cj0KCQiAvJXxBRCeARIsAMSkApqY9BBWjslaJA5PLzVT7qnP36iVSDKkQ2tk8DbdCzk909RKYiYm76kaAvyVEALw_wcB   https://www.amazon.com/JPSOR-Scientific-Changing-Reactive-Plastic/dp/B01LZFI7AF/ref=asc_df_B01LZFI7AF/?tag=hyprod-20&linkCode=df0&hvadid=198064277648&hvpos=1o3&hvnetw=g&hvrand=12129056433328399856&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007324&hvtargid=pla-350869888021&psc=1   And thousands (yes, thousands) of other sources.   Peter Wieck Melrose Park, PA

Stephen Wolstenholme <steve@easynn.com>: Jan 20 03:18PM On Sat, 18 Jan 2020 16:11:01 -0500, KC JONES <kcharlie@nowhere.net> wrote:   >years, but recently brought it out to sterilize a room where a person >had been sick. However, I don't know if it still emits the germ killing >UVC spectrum. What's a quick way I could tell for sure? Thanks.   All the UVC lights I have ever used have some part of the visible spectrum. See if white items "glow".   Steve   -- http://www.npsnn.com

Cursitor Doom <curd@notformail.com>: Jan 19 06:18PM Gentlemen,   Would I be correct in thinking that if you have an item of test equipment with a CRT display and it's dim and when you try to turn up the brightness it actually gets dimmer for the last bit as you get towards maximum? And there's nothing you can do about it; it's only fit for spare parts?   tia --   No deal? No problem! :-D

John-Del <ohger1s@gmail.com>: Jan 19 01:39PM -0800 On Sunday, January 19, 2020 at 1:18:51 PM UTC-5, Cursitor Doom wrote:   > tia > --   > No deal? No problem! :-D     Lots of circuit maladies will simulate a weak CRT. Start with voltage readings, move to waveforms. Low high voltage will cause the picture to dim as the drive to the tube is increased for instance.

Cursitor Doom <curd@notformail.com>: Jan 19 10:40PM On Sun, 19 Jan 2020 13:39:12 -0800 (PST), John-Del <ohger1s@gmail.com> wrote:   >Lots of circuit maladies will simulate a weak CRT. Start with voltage readings, move to waveforms. Low high voltage will cause the picture to dim as the drive to the tube is increased for instance.   I was given to understand elsewhere (which is why I'm double-checking here) that a CRT which has gone dim and reaches its peak brightness before dimming again towards the end of the intensity control sweep is irretrievably fucked and not worth further investment in time. It would be nice if that advice is indeed incorrect!   --   No deal? No problem! :-D

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 03:02PM -0800 On Sun, 19 Jan 2020 18:18:49 +0000, Cursitor Doom   >Gentlemen,   Hardly.   >the brightness it actually gets dimmer for the last bit as you get >towards maximum? And there's nothing you can do about it; it's only >fit for spare parts?   No. You would NOT be correct. Find the service manual of your unspecified model piece of antique test equipment, and check the voltages in the CRT and Hi-V section. Use a Hi-V probe if you value your life and your DMM. My guess(tm) is that you'll find some form of component failure or deterioration, such as a burnt resistor, leaky capacitor, arcing flyback, sick hi-v diode, or the usual high ESR electrolytic capacitor. Plenty of possibilities.   Now, I have question. Is there some reason you chronically fail to provide the maker and model number of what you are working on? I'm wondering if you have a pathological aversion towards numbers, or perhaps you might be embarrassed by your choice of test equipment.   -- 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

John Robertson <spam@flippers.com>: Jan 19 10:44PM -0800 On 2020/01/19 3:02 p.m., Jeff Liebermann wrote: > component failure or deterioration, such as a burnt resistor, leaky > capacitor, arcing flyback, sick hi-v diode, or the usual high ESR > electrolytic capacitor. Plenty of possibilities.   Also, some of us have CRT test fixtures that can also restore/rejuvenate almost any picture tube/CRT - B&K model 490 for example.   If the image grows/shrinks when you change the brightness, then there is usually a fault with the HV diode, especially in B&W CRTs.   I'd first look at the electrolytic caps in this unit - most are past their best before date... When replacing the caps take care to use caps specced for the circuit they are being used in. And try using a good quality cap like Panasonic from Digikey or Mouser. Not crap from eBay...   > provide the maker and model number of what you are working on? I'm > wondering if you have a pathological aversion towards numbers, or > perhaps you might be embarrassed by your choice of test equipment.   That might be considered to be cheating - actually providing useful background information...   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Cursitor Doom <curd@notformail.com>: Jan 20 09:56AM On Sun, 19 Jan 2020 15:02:37 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >provide the maker and model number of what you are working on? I'm >wondering if you have a pathological aversion towards numbers, or >perhaps you might be embarrassed by your choice of test equipment.   I didn't want to limit it to one specific item, Jeff; just wanted to make the question as general to CRO test equipment as possible. Someone opined thusly about the matter on some discussion forum and I thought it might be useful to keep it in mind for future eventualities, that's all! Anyway, it was bad advice, clearly.   --   No deal? No problem! :-D

Cursitor Doom <curd@notformail.com>: Jan 20 09:59AM On Sun, 19 Jan 2020 22:44:02 -0800, John Robertson <spam@flippers.com> wrote:   >usually a fault with the HV diode, especially in B&W CRTs.   >That might be considered to be cheating - actually providing useful >background information...   Since you didn't read the question in the first place I'll excuse myself on that one. The issue was *not* about the image shrinking/growing during intensity adjustment!! --   No deal? No problem! :-D

edu.gimeno.0@gmail.com: Jan 19 01:41PM -0800 Hi There. I have this weird device that is not fully working. It is a keypad used to control several tools in a harvester. It uses CAN bus to communicate with the devices in the machine. When it is powered on, it should flash all the buttons for a second, and then only the functions that are active, should remain lit. If you press a button, it should send a CAN msg and corresponding light behind the button should turn on/off.   The broken keypad still keeps its control abilities 100%, but you have to work blind, as the leds behind the keys don't light up at all. No powerup test flash, no working lights, nothing, but when you press a button, the specific tool is activated, so CAN connectivity seems ok.   Inside, it has 2 boards. Board A (check pics) has connections to harvester. Only 12V, GND, CAN-H and CAN-L are used in a real harvester. It has several transistors, probably for functions that are directly driven by the board, probably connected to the spare plugs, never seen them in use. It has a small connector to board B. Connector only has GND, VCC, CANH/L and 2 more unknown pins.   Board B has all the logic to drive the CAN signals and the LEDS. LEDS seem to be RGB, as they are driven by several pins, and I have seen them flashing in different colors. Each key has 2 leds. One helps you locate the function it does at night, other turns on/off whether the associated tools is activated or not. This is the faulty board, when I use this board on another Board A, it still fails.   IC's on this board are: 1xTLE4473 GV53, this is a LDO dual output regulator, for 3.3v and 5v (5v seems to be inhibited and unused) 2x762T, these are power FET switches. I think one activates TE11 and other activates TE12. 1xA1051/3, this is the CAN line driver, to interface with microcontroller 2xTCL5943, these are 16 output LED drivers 1 microcontroller 1x93LC86, this is an EEPROM for the microcontroler   As everything but the lights seem to work fine, I believe the problem is in some current driver for the LEDs set, but I can't tell how it could be driven.   I have a complete working set and another broken set (only board B is actually failing, as tested exchanging boards)   Can you provide any help on how to diagnose what could be wrong?   I uploaded pics of both boards (you can ignore board A) on both sides, and one of front B with annotated IC's markings   Thanks in advance! Link to photos: https://drive.google.com/drive/folders/1TvrYybxXDohq4cmN92YEnCmBARS9T8Df?usp=sharing

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 03:27PM -0800 On Sun, 19 Jan 2020 13:41:33 -0800 (PST), edu.gimeno.0@gmail.com wrote:     >have to work blind, as the leds behind the keys don't light up at all. >No powerup test flash, no working lights, nothing, but when you press >a button, the specific tool is activated, so CAN connectivity seems ok.   Good. The problem is therefore isolated to whatever is driving the LED lights. I count 18 LED's. On board B back, carefully remove the black plastic insulator so that you can trace the LED wires. Try to determine which chip, resistor pack, or whatever is driving the LED's.   I can't read the part number off the photos. The two TCL5943 seem to be likely cause of the problem. However, I can't find anything with Google for that part number. Are you certain that they are a TCL5943 or are they something else? Can you find a data sheet? Also, I find it odd that the device would require 32 outputs to drive 18 LEDs. Are there more LEDs somewhere as most of the outputs on both chips seem to go somewhere.   Plug everything back together and check for power and switching waveforms (for LED dimming) on all the TCL5943. I would be more specific if I could find a data sheet on this device. Basically, start with any LED and trace the signals and DC back through the TCL5943 chips, and on to whatever powers the chip.   My guess(tm) is one of the chip resistors on the PCB is acting as a fuse, and it's blown. I looked for something that looked like a fuse such as "F1" reference designator, but found nothing.   >Link to photos: https://drive.google.com/drive/folders/1TvrYybxXDohq4cmN92YEnCmBARS9T8Df?usp=sharing   Good luck.   -- 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

Michael Terrell <terrell.michael.a@gmail.com>: Jan 19 03:45PM -0800 On Sunday, January 19, 2020 at 6:28:04 PM UTC-5, Jeff Liebermann wrote: > a fuse, and it's blown. I looked for something that looked like > a fuse such as "F1" reference designator, but found nothing.   > >Link to photos: https://drive.google.com/drive/folders/1TvrYybxXDohq4cmN92YEnCmBARS9T8Df?usp=sharing   Maybe it is a TLC5943?   http://www.ti.com/product/TLC5943 16-bit ES-PWM with 7-bit Device Level Brightness Control

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 05:16PM -0800 On Sun, 19 Jan 2020 15:45:11 -0800 (PST), Michael Terrell   >Maybe it is a TLC5943? >http://www.ti.com/product/TLC5943 16-bit ES-PWM with 7-bit Device Level Brightness Control   Oops. Telephone call and visitor interruption induced dyslexia. Ummm... thanks.   Continuing from where I fumbled the ball: <http://www.ti.com/product/TLC5943/technicaldocuments> <http://www.ti.com/lit/ds/symlink/tlc5943.pdf>   Start by looking for Vcc of 3 - 5VDC on pin 28. If that's missing, look for something open in the 12V to 5V(?) power supply section. My guess(tm) is still a well hidden fuse in this area.   The LED current is controlled by a resistor to ground at IREF pin 27. Make sure this resistor is the correct value. See Fig 14 (Pg 13) for resistor value and LED current. Check resistor with an ohmmeter (with the power disconnected from the device).   Please verify that all 18 LED's are connected to a common power wire and that it has VCC on this common power wire. See VLED on Pg 1 "Typical Application Circuit".   The LED brightness is set digitally by the controller. Check for data and the correct levels on all the pins labeled "I" (input) on Pg 8. Verify that XTEST ping is either pulled high or grounded (but not open or floating).           -- 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

edu.gimeno.0@gmail.com: Jan 19 11:45PM -0800 El lunes, 20 de enero de 2020, 2:16:57 (UTC+1), Jeff Liebermann escribió: > and the correct levels on all the pins labeled "I" (input) on Pg 8. > Verify that XTEST ping is either pulled high or grounded (but not open > or floating).   Yes Sorry, there was a typo in the LED driver part number. It was TLC. There are no components in the LED side hidden by the black plastic neither discrete nor active. Just traces I will definitely check those values tonight, thanks a lot!

Jeff Liebermann <jeffl@cruzio.com>: Jan 19 02:55PM -0800 On Sun, 19 Jan 2020 10:10:50 +0000, Cursitor Doom   >>The round top is an epoxy glob covering the die, which sits on the flat thick sheet material that holds the leads. 2 tone ones make this easy to see, all black ones not so much.   >Ah. Ok. I have a few hundred of those but some obscure part numbers >and all PNP so are unlikely to be called into service here. :)   Those bring back not so fond memories. The black potting epoxy was optically transparent to infrared light. I had a hell of a time dealing with weird problems in the 1960's until I found the light sensitivity problem with those transistors. It took about a year for Fairchild to clear their inventory and screw their unsuspecting customers by continuing to sell these devices. Eventually, they changed over to the "PN" (TO-92) style package, which initially was made from silicon epoxy instead of epoxy-B. Silicon epoxy shrinks slightly at high temperatures, causing the corrosive fluxes from the wave soldering equipment to creep up the transistor leads by capillary action, and corrode the leads and chip. We had to x-ray the dead parts to determine the failure mode and guess the cause. It usually took about a month for the transistors to rot to death. I had a difficult time getting Fairchild to understand that having *ALL* the transistors on a PCB fail almost simultaneously after only a month was sufficient grounds for suspecting that something might be wrong with the parts. They eventually switched to epoxy-B, but only after again unloading their defective inventory on unsuspecting customers. There was also a problem with the UA2136 IF amp/detector IC, where chips made in different Fairchild factories produced radically different performance and stability. I took great pride in personally removing Fairchild from the approved vendor/manufacturers list, and finding alternate sources for about $2.5 million/year of their components. When I mentioned this to the sales rep, he acted like he didn't care or it wasn't important.   -- 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

Trevor Wilson <trevor@rageaudio.com.au>: Jan 20 10:04AM +1100 On 20/01/2020 9:55 am, Jeff Liebermann wrote: > alternate sources for about $2.5 million/year of their components. > When I mentioned this to the sales rep, he acted like he didn't care > or it wasn't important.   **Oh, now that is interesting stuff.   -- Trevor Wilson www.rageaudio.com.au

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