- Transformer shot! (was scope SMPS/ capacitor venting) - 8 Updates
- Chip in e-cigarette battery. - 7 Updates
- Greasing up switches and connectors? - 5 Updates
| jurb6006@gmail.com: Mar 06 09:06AM -0800 On Wednesday, March 2, 2016 at 4:28:56 PM UTC-5, Dimitrij Klingbeil wrote: > > HTH. > You must be meaning X10 setting. Common scope inputs as well as probes > are not designed to handle the typical peaks from power supplies at X1. The quote function musta got screwed up. I always use 10X unless I really need the gain, which is rare. I also recommend others use the 10X at all times as well. Not only does it reduce circuit loading, it also protects the scope to some extent. Not the first time Usenet quoting got screwed up. I expect to see >> on a quote of a quote and > on a direct quote but it seems not to work that way all the time. |
| legg <legg@nospam.magma.ca>: Mar 06 01:28PM -0500 When you've got this thing plugged in and running, what is visible in the display? Can you get a locator dot? Traces in free-run? RL |
| Cursitor Doom <curd@notformail.com>: Mar 06 09:18PM On Sun, 06 Mar 2016 13:28:52 -0500, legg wrote: > When you've got this thing plugged in and running, what is visible in > the display? Can you get a locator dot? Traces in free-run? I haven't tried this yet as I can guess sod's law making it the case that I'd have to pull the plug just at the point where the CRT has warmed up sufficiently. The other slight problem is to test this requires the board to be completely inserted with every connection made plus a temp probe to the power resistor which is all rather fiddlesome and not to be done repeatedly if it can be avoided. I can see a situation arising (sod's law again) where someone here will post saying - "oh, whilst you still have the board out, just check this..." Nevertheless, if nothing is said in the next 18 hours, I will test it all reconnected and post the outcome here. |
| Dimitrij Klingbeil <nospam@no-address.com>: Mar 06 11:34PM +0100 On 06.03.2016 14:35, Cursitor Doom wrote: > 20.64kHz. (This is with the load connected.) I then tried again with > V1812 re-inserted and got 20.62kHz. Apologies for the earlier > error... Okay, that makes the difference somewhat less. Still higher than 17.35 kHz obviously. If I understood the service manual correctly, they seem to suggest to start from the lowest frequency when performing an adjustment and going up until output regulation is reached. (They write from "fully counter-clockwise" actually, referring to the "FREQ" trimmer, and looking at the schematic that would likely be from the "lowest" position of the wiper, meaning starting at the highest resistance and going towards lower resistance.) It's only my guess, but I think that they intended this supply to run rather somewhere below resonance than somewhere above. This would mean that adjusting the pulse frequency down to 17.35 kHz should do no harm as that value would be lower than the setting right now. If there was any danger of something blowing up by setting the frequency lower, they would not be recommending to set it to the absolute minimum before slowly adjusting it back "up" again. Can you adjust the pulse rate to 17.35 kHz and then test the supply with a dummy load? Can you test it with a variac and see if it still maintains output in regulation down to 175 V "mains" (adjusted to 17.35 kHz, that is)? Regards Dimitrij |
| Cursitor Doom <curd@notformail.com>: Mar 06 11:23PM On Sun, 06 Mar 2016 23:34:55 +0100, Dimitrij Klingbeil wrote: > looking at the schematic that would likely be from the "lowest" position > of the wiper, meaning starting at the highest resistance and going > towards lower resistance.) OK, well I can easily establish that safely by popping V1812 out of circuit temporarily so sweeping the frequency adjustment pot won't have any effect. > If there was any danger of something blowing up by setting the frequency > lower, they would not be recommending to set it to the absolute minimum > before slowly adjusting it back "up" again. Indeed. That seems to be the key point I have to observe. > Can you adjust the pulse rate to 17.35 kHz and then test the supply with > a dummy load? Well I could.... But that's spot on resonance. I was under the impression that they're not supposed to run actually directly at resonance? > Can you test it with a variac and see if it still maintains output in > regulation down to 175 V "mains" (adjusted to 17.35 kHz, that is)? Yes, no problem. It seems the key regulated output is the 12.7V one and if that's correct, the rest should follow. There's a trimmer for 12.7V on the underside of the board. Thanks again, Dimitrij. I'll report back tomorrow... |
| legg <legg@nospam.magma.ca>: Mar 06 07:27PM -0500 On Sun, 6 Mar 2016 21:18:58 -0000 (UTC), Cursitor Doom >the board out, just check this..." >Nevertheless, if nothing is said in the next 18 hours, I will test it all >reconnected and post the outcome here. As long as you haven't been fooling with psu trimpots, you can forget about the resistor. If you have been fooling with trim pots, then you'll have to follow the manual adjustment procedure first...assuming similarity to PM3262. (check pot rotation effects expected between models). Forget about the resistor while you're doing this. Continue to forget about this resistor until (and if ever) V1811 dies again. RL |
| Cursitor Doom <curd@notformail.com>: Mar 07 12:51AM On Sun, 06 Mar 2016 19:27:19 -0500, legg wrote: [...] I am happy to assure you that I have not touched a single trimmer so far and neither will I be dismissing the heating of the power resistor, which is clearly indicating that something is still amiss here. |
| Cursitor Doom <curd@notformail.com>: Mar 07 01:46PM On Sun, 06 Mar 2016 23:34:55 +0100, Dimitrij Klingbeil wrote: > rather somewhere below resonance than somewhere above. This would mean > that adjusting the pulse frequency down to 17.35 kHz should do no harm > as that value would be lower than the setting right now. I've just noticed that towards the bottom of (true) page 106, it states the following:- "The oscillator frequency is approximately 25kHz, determined by network C1811, R1823 and is adjustable by means of R1824." It then goes on to specify the duty cycle. Two things stand out as requiring further investigation here. Clearly, the 25kHz clock frequency mentioned is *miles* away from what my clock is running at - and the frequency adjustment is made with R1827, not R1824 (which is fixed anyway). I'm guessing the reference to R1824 is just a typo, but can we say the same for 25kHz?? Since this *completely* changes our former assumptions, I'm going to confine myself to just replacing the flaky polyester caps for the time being. Be interested to hear how you think I should proceed now in the light of this... |
| "Ian Field" <gangprobing.alien@ntlworld.com>: Mar 06 06:04PM "M Philbrook" <jamie_ka1lpa@charter.net> wrote in message news:MPG.31452d64379c3a42989e9a@news.eternal-september.org... > belongs > No one needs them, just like the real thing, they don't need them > ether... At the end of the day; that chip is a lithium cell charge controller. Most of my home brew lithium chargers require supervision, the charge board from an e-cig can be left to get on with it - even if it takes a long time to charge a decent sized cell. |
| Jeff Liebermann <jeffl@cruzio.com>: Mar 06 10:59AM -0800 On Sat, 5 Mar 2016 18:23:49 -0000, "Ian Field" >The manufacturer may have slipped up on the house coded chip. >In one unit the chip was marked; 3417WA, in the other it was marked; >Esmoke33716M. I couldn't find anything on the specific chip. I suspect it's custom and well protected. This should help explain what's going on inside: <http://se.azinstall.net/2015/10/hacking-vuse-e-cig-puff-counter.html> As for e-cigs and vaping, I don't indulge and see no value in breathing fumes. However, a friends son got involved with the vaping scene and has demonstrated to me that there's plenty of demand and money available. They're generally banned in public places, which I guess adds to the mystique. Judging by the consumption of 18650 LiIon batteries, e-cigs have not only helped lower the price of these batteries, but have greatly contributed to my growing collection of half-dead 18650 cells. If you read candlepower forums or the various e-cig forums, you'll find plenty of discussion about which batteries are best (or cheapest). That gets my attention. -- 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 |
| Jeff Liebermann <jeffl@cruzio.com>: Mar 06 11:09AM -0800 On Sun, 6 Mar 2016 18:04:58 -0000, "Ian Field" >At the end of the day; that chip is a lithium cell charge controller. Yes, with the added bonus of a puff counter and copy protection system: <http://se.azinstall.net/2015/10/hacking-vuse-e-cig-puff-counter.html> >Most of my home brew lithium chargers require supervision, the charge board >from an e-cig can be left to get on with it - even if it takes a long time >to charge a decent sized cell. I've been experimenting with fast charging 18650 cells at 4A. So far, I've confirmed that I can charge at the data sheet rate without damage but only if I keep the cell cool and not try to get too close to 100% charge. The quality of the cell also makes a big difference. The typical "Fire" type cells are junk and are rarely capable to meeting their stated capacity (ma-hr). Therefore using a data sheet max charge rate is the same as charging too fast. I've destroyed a few cells verifying the problem. Also, heavily used cells are at reduced capacity, which also requires a reduced fast charge current and time. In other words, you don't have to wait a long time for it to charge, but only if you know the capacity and can control the temperature. I use a water bath, but that's not suitable for General Public. <http://vapingunderground.com/threads/charging-18650-batteries-at-2-0-amp.41432/> -- 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 |
| Jeff Liebermann <jeffl@cruzio.com>: Mar 06 11:17AM -0800 On Sat, 5 Mar 2016 20:21:45 -0500, M Philbrook > Did I miss something ? Yes. Nerds are often considered cool. I'm the consummate nerd, geek, and hodad all my life. For many years, this was anything except cool. The women would hang around with the sex athletes and those with the cool toys and just make fun of the nerds. Then, we all grew up together. Today, I'm being chased by about 5 women (I sometimes loose count). Their lives with the sex athletes and toy collectors have turned into life with a viagra addict and bankruptcy. Suddenly, nerds are starting to look very interesting. After about age 45 and when the kids are gone, I'm now the major attraction. As an added bonus, I don't smoke or vape, so I might survive a bit longer than most. -- 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 |
| "Ian Field" <gangprobing.alien@ntlworld.com>: Mar 06 07:43PM "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:4hvodbl5vc5gqmr5krh5414mrfia729lad@4ax.com... > I've been experimenting with fast charging 18650 cells at 4A. So far, > I've confirmed that I can charge at the data sheet rate without damage > but only if I keep the cell cool and not try to get too close to 100% The ones I've been doing so far are basically a TL431 shunt regulator - there are various ways to boost the current rating with external transistors. Nothing bad has happened yet - but I take care not to leave them charging too long. The current experiment is charging a 3x3 18650 laptop pack. The charger is an 8uF wattless dropper on 50Hz, no safety circuits - so it can only be on charge while I'm there monitoring it. 3 sessions so far, and its only up to 11.8V. |
| "Ian Field" <gangprobing.alien@ntlworld.com>: Mar 06 07:47PM "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:kiuodb9p0n70aljd0jgd7mr5la73jgh59v@4ax.com... > I couldn't find anything on the specific chip. I suspect it's custom > and well protected. This should help explain what's going on inside: > <http://se.azinstall.net/2015/10/hacking-vuse-e-cig-puff-counter.html> It (was) a Vapestick and doesn't look that sophisticated. 2 of the units had batteries that didn't take any charge current, the 3rd one still lit its LED when the button was pressed so I didn't scrap it. |
| "pfjw@aol.com" <pfjw@aol.com>: Mar 07 05:45AM -0800 On Sunday, March 6, 2016 at 2:17:34 PM UTC-5, Jeff Liebermann wrote: > I'm now the major attraction. It ain't nohow personal. Widowed (or reasonably divorced) single heterosexual males over 45, who are also financially viable, are in short supply. First, women live longer than men, statistically, and second most men in that demographic are married. There is a widowed gentleman down the street from us, entirely normal looking, but with a good job, and also a pet owner. He also seems to be fighting them off - and with good humor. He blames his black lab. Tobacco users are worse then lepers. Lepers can be cured. Peter Wieck Melrose Park, PA |
| Kevin McMurtrie <mcmurtrie@pixelmemory.us>: Mar 06 09:00AM -0800 In article <0001HW.1C8B4B670002EE5111CD2E3CF@news.eternal-september.org>, > contra-indicated. > What say y'all? > Thanks. Grease is more easily pinched through than corrosion. It extends the life of sliding switches by reducing friction. It's only used for low level signal switching. Grease and oil slow down switching time so they'll cause power switches to arc and catch fire. -- I will not see posts from astraweb, theremailer, dizum, or google because they host Usenet flooders. |
| Jeff Liebermann <jeffl@cruzio.com>: Mar 06 10:41AM -0800 >> would want in an RF connector. >Jeff, I think he means he uses it under the boot, not inside the connector… >Dave Yep. "...under the weather boot to keep the oxidation down". My apologies for expanding the topic, but I assumed that connector performance was more important than surface cosmetics. The problem with petroleum based greases, such as GC 10-8101 which is about 10-15% mineral oil, is they cause the rubber boot and F connector O-ring seal, to swell and possibly deteriorate depending on rubber composition. I must admit that I've never seen it happen where it can be easily attributed to grease because nobody around here covers the outsides of TV/CATV/TVRO/DBS connectors with grease. For more expensive RF connectors, where water incursion is a problem, I wrap the connectors with PTFE tape followed by a layer of electrical tape. Then some clear acrylic spray to reduce UV deterioration. Another problem is that greases like to migrate when warm. I can usually tell when someone has stuffed a connector full of grease because the grease eventually appears on the outside of the connector where it accumulates dirt and dust. Capillary action also works for viscous fluids, like grease. I've been told that F connector threads are designed to be a rather loose fit to handle expansion caused by corrosive products (aluminum oxide) and not jam the threads. If true, such threads would not make a very good seal. The phone monopolies have the same problem with outdoor NID (network interface device) boxes, which have at least one RJ11 connector. The gold connector wires can take care of themselves, but the copper flat ribbon cable that connect to the RJ11 are a problem. Instead of grease, they use a very viscous polydimethylsiloxane (silicone) gel to seal the connector area. There's a tech description near the bottom of the patent: <http://www.google.com/patents/US6971897> A gel doesn't run when hot and doesn't seem to attract dirt because it's fairly non-sticky. Note that all the references at the bottom are for a "gel" compound, not a "grease". -- 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 |
| stratus46@yahoo.com: Mar 06 01:05PM -0800 On Saturday, March 5, 2016 at 9:11:03 PM UTC-8, DaveC wrote: > > would want in an RF connector. > Jeff, I think he means he uses it under the boot, not inside the connector... > Dave I actually put it directly on the center conductor after the connector is attached and then screw it on the fitting. While the grease is an 'insulator', the metal parts touch and the grease prevents moisture getting to the wire. I did not put any grease on the rubber boot except for any residue that was on the outside of the connector. G² |
| "Ian Field" <gangprobing.alien@ntlworld.com>: Mar 06 09:34PM "DaveC" <not@home.cow> wrote in message news:0001HW.1C8B4B670002EE5111CD2E3CF@news.eternal-september.org... > kind of grease in it. > …which has always confused me: grease is an insulator (well, the grease in > this switch is—just tested and it's infinite ohms). When I worked for a calibration firm, they had special contacts grease for the old decade boxes. AFAICR: it was called Elvolube - but I haven't been able to find it online. Often I use GT85 - its like WD40 but PTFE enhanced, it doesn't interfere with contacts but the solvent destroys any ABS plastics in anything you spray it on. |
| N_Cook <diverse@tcp.co.uk>: Mar 07 07:51AM On 05/03/2016 17:14, DaveC wrote: > contra-indicated. > What say y'all? > Thanks. Can we summarise this thread by saying - Any grease is better than no grease, in low voltage, wiped contact situations, as long as the grease doesn't go hard with age or otherwise degrade or corrode the contacts itself |
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