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DaveC <not@home.cow>: Mar 22 01:41PM -0700 Circuit:   http://imgur.com/YeELiHI   which is identical to the application note in the datasheet (scroll down to the ME2108A diagrams):   http://img.ozdisan.com/ETicaret_Dosya/431770_1622138.pdf   (easily translated via Google, but a bit more confusing...)   Measured current at the battery terminals is 275 mA (due to meter insertion loss it's difficult to get an accurate current reading at the LED's terminals--the LED dims). Voltage across the LED is a pretty-constant 4v. Estimating the efficiency of the converter at (roughly) 75 percent the LED is using 825 mW.   I guess I'm looking for a 1W replacement?   How's my math?   Thanks.

Jeff Liebermann <jeffl@cruzio.com>: Mar 22 04:42PM -0700 >Nebo NU15J: >https://www.nebotools.com/prod_details.php?id=31&cid=16&subid=94&subsubcid=   Looks like the flashing LED is a common problem: <http://www.candlepowerforums.com/vb/showthread.php?417142-Replacement-LED>   >I like this model for its good trade-off between brightness and battery life.   Some day, someone will design a flashlight with an automatic PWM light dimmer. Shine the light at something bright, and the flashlight runs at full brightness. Shine it at something in the dark, and it goes to fairly dim.   >No controller chip. Looks like a boost converter (inductor, BJT, schottky >diode, ceramic cap).   Yep, that's about it. No controller.   >small--20mv?--rise and fall as it switches on and off). Haven't yet >measured current. Surely if there was a bad solder joint or other failure it >would show up here.   Ok, I'm wrong. The flashing is not caused by the non-existent controller chip.   >Thanks for the referrals of other lights, but I'm not buying a replacement. >I'm doing this for fun and to learn.   Like I mumbled previously, see if there's a dome type LED under a plastic lens. You'll probably need to unsolder the LED leads to do this. If they really are two parts, it should be possible to find a replacement LED.   If you can't identify the LED by the power output, try measuring the current drain with a new battery. Multiply the current with your measured 4V, and you should get the power in watts. That should tell you if you should be looking for a 1/2, 1, or 1.5v LED.   -- 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

DaveC <not@home.cow>: Mar 22 04:56PM -0700 Jeff Liebermann sez:   > Looks like the flashing LED is a common problem: > <http://www.candlepowerforums.com/vb/showthread.php?417142-Replacement-LED>   That's my post on canblepowerforums.com. (c: > Like I mumbled previously, see if there's a dome type LED under a plastic lens. You'll probably need to unsolder the LED leads to do this. If they really are two parts, it should be possible to find a replacement LED.   Will do. > current drain with a new battery. Multiply the current with your > measured 4V, and you should get the power in watts. That should tell > you if you should be looking for a 1/2, 1, or 1.5v LED.   You mean 1/2, 1, or 1.5 *watt* LED, yes?   Thanks.

Jeff Liebermann <jeffl@cruzio.com>: Mar 22 06:16PM -0700 >> Looks like the flashing LED is a common problem: >> <http://www.candlepowerforums.com/vb/showthread.php?417142-Replacement-LED>   >That's my post on canblepowerforums.com. (c:   Oops(tm).   >> measured 4V, and you should get the power in watts. That should tell >> you if you should be looking for a 1/2, 1, or 1.5v LED.   >You mean 1/2, 1, or 1.5 *watt* LED, yes?   Oops 2.0(tm). I was in a rush to get out of door. Sorry. Also, I just noticed that there is no such thing as an individual 1.5w LED. -- 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

rickman <gnuarm@gmail.com>: Mar 22 09:46PM -0400 On 3/22/2016 4:41 PM, DaveC wrote: > using 825 mW.   > I guess I'm looking for a 1W replacement?   > How's my math?   Didn't you say it used a *single* 1.5 volt AA cell? I think that would make it 412 milliwatts not counting the conversion efficiency, so more likely a 1/2 watt LED.   --   Rick

DaveC <not@home.cow>: Mar 22 06:56PM -0700 > Also, I just noticed that there is no such thing as an individual 1.5w LED.   I think this is an under-used(?) 1W LED.   If I can’t find a direct replacement I’m considering flipping the PCB it’s soldered to and using the copper side to solder a SMD unit. That way can dissipate some W.   But that presents its own set of problems. Optics will need to be matched to the new LED.   Hmm...

DaveC <not@home.cow>: Mar 22 07:00PM -0700 On 22 Mar 2016, rickman wrote   > Didn't you say it used a *single* 1.5 volt AA cell? I think that would > make it 412 milliwatts not counting the conversion efficiency, so more > likely a 1/2 watt LED.   1.5v boosted to 4v (measured) output from the converter. 275 mA (measured) at the battery terminals. I make that to be 1100 mW. If presume 75 percent efficiency, 825 mW.   No?

rickman <gnuarm@gmail.com>: Mar 23 12:19AM -0400 On 3/22/2016 10:00 PM, DaveC wrote: > the battery terminals. I make that to be 1100 mW. If presume 75 percent > efficiency, 825 mW.   > No?   Perhaps I am missing something. The battery terminals will be at the battery voltage, no? So why would you use 4 volts which is at the output? It would be 4 volts times the LED current or the battery voltage times the input current.   --   Rick

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 22 09:46PM Right,     I would really like a very small, cheap, air tank that I can charge every now and again at the local garage (i.e. can be filled with a standard car tyre pump). I would also like it to include one of these, to blow all the dust from the heatsinks and chassis in Power Amplifiers, amongst other things.   http://www.ebay.co.uk/itm/VINTAGE-1986-HEAVY-DUTY-CLIP-ON-AIR-BLOW-GUN-PORTABLE-AIR-TANK-/281924138448?hash=item41a3fcf5d0:g:QPYAAOSwpzdWrsUq       Does such a thing exist? Are retail tyre pumps powerful enough to charge these? I've been Googling but don't know the connector terminology that says "you can charge this with your local tyre pump".   I've found lots of portable air tanks aimed at Motorsports, but I'm really not sure about the local tyre pump mechanism thingy to charge it.     Cheers,     Gareth.

MOP CAP <email@domain.com>: Mar 22 03:04PM -0700 On 2016-03-22 21:46:56 +0000, Gareth Magennis said:   > really not sure about the local tyre pump mechanism thingy to charge it.   > Cheers,   > Gareth.   Go to Harbor Freight. They list five.   CP

"Ralph Mowery" <rmowery28146@earthlink.net>: Mar 22 06:19PM -0400 "MOP CAP" <email@domain.com> wrote in message news:20160322150453792-email@domaincom... >> I've found lots of portable air tanks aimed at Motorsports, but I'm >> really not sure about the local tyre pump mechanism thingy to charge it.   > Go to Harbor Freight. They list five.   Just buy one of the small air compressors at HF for under $ 100. If your hose does not leak, you can keep the tank filled up for a while before you need to run the compressor part.     If you want to , you can buy just the portabel tank and fill it anywhere there is an air supply, hopefully around 100 or so psi.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 22 10:21PM "Ralph Mowery" wrote in message news:rdWdnVD34aYXXmzLnZ2dnUU7-X3NnZ2d@earthlink.com...     "MOP CAP" <email@domain.com> wrote in message news:20160322150453792-email@domaincom... >> I've found lots of portable air tanks aimed at Motorsports, but I'm >> really not sure about the local tyre pump mechanism thingy to charge it.   > Go to Harbor Freight. They list five.   Just buy one of the small air compressors at HF for under $ 100. If your hose does not leak, you can keep the tank filled up for a while before you need to run the compressor part.     If you want to , you can buy just the portabel tank and fill it anywhere there is an air supply, hopefully around 100 or so psi.             Sorry, I forgot to include that I do not live in North America. I am in the UK.     Cheers,     Gareth.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 22 11:44PM "Ralph Mowery" wrote in message news:rdWdnVD34aYXXmzLnZ2dnUU7-X3NnZ2d@earthlink.com...     "MOP CAP" <email@domain.com> wrote in message news:20160322150453792-email@domaincom... >> I've found lots of portable air tanks aimed at Motorsports, but I'm >> really not sure about the local tyre pump mechanism thingy to charge it.   > Go to Harbor Freight. They list five.   Just buy one of the small air compressors at HF for under $ 100. If your hose does not leak, you can keep the tank filled up for a while before you need to run the compressor part.     If you want to , you can buy just the portabel tank and fill it anywhere there is an air supply, hopefully around 100 or so psi.             I don't think you are getting my question.   I would like something like a small Fire Extinguisher I can have near to my bench, not a big noisy compressor I have to store somewhere.       Gareth.

"(PeteCresswell)" <x@y.Invalid>: Mar 22 07:51PM -0400 Per Gareth Magennis: >I would really like a very small, cheap, air tank that I can charge every >now and again at the local garage (i.e. can be filled with a standard car >tyre pump).   Harbor Freight, as others have observed, is probably a good bet.   But how small?   If you want *really* small, start Googling "Paint Ball Guns". The paint ball people who do not use CO2 use compressed air and the tanks are quite small - yet hold something like 800 PSI. -- Pete Cresswell

"Ralph Mowery" <rmowery28146@earthlink.net>: Mar 22 08:00PM -0400 "Gareth Magennis" <soundserviceleeds@outlook.com> wrote in message news:UNkIy.80081$hz.37884@fx42.am4...   > I don't think you are getting my question.   > I would like something like a small Fire Extinguisher I can have near to > my bench, not a big noisy compressor I have to store somewhere.   No, we are not getting the question. Going by what you sent, the tank is about a foot in diameter and 2 feet long. Or 1/3 of a meter in diameter and a meter and a half long. The tanks are usually made to carry out on the road and blow up car tires.   You now appear to want a tank about 3 or 4 inches in diameter and a foot long. You probably would not get enough air in it to do much at 100 psi or so that many of the stations supply.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 23 12:01AM "Ralph Mowery" wrote in message news:qd2dnRGsIqfCRmzLnZ2dnUU7-VfNnZ2d@earthlink.com...     "Gareth Magennis" <soundserviceleeds@outlook.com> wrote in message news:UNkIy.80081$hz.37884@fx42.am4...   > I don't think you are getting my question.   > I would like something like a small Fire Extinguisher I can have near to > my bench, not a big noisy compressor I have to store somewhere.   No, we are not getting the question. Going by what you sent, the tank is about a foot in diameter and 2 feet long. Or 1/3 of a meter in diameter and a meter and a half long. The tanks are usually made to carry out on the road and blow up car tires.   You now appear to want a tank about 3 or 4 inches in diameter and a foot long. You probably would not get enough air in it to do much at 100 psi or so that many of the stations supply.         I only want to blow the dust out of a power amplifier occasionally. I can buy a can of air do do that, but it is expensive.   Surely there exists a small compressed air bottle that you can recharge at your local garage do do that same job.       Gareth.

etpm@whidbey.com: Mar 22 05:26PM -0700 On Tue, 22 Mar 2016 21:46:56 -0000, "Gareth Magennis" >not sure about the local tyre pump mechanism thingy to charge it.   >Cheers,   >Gareth.   Greetings Gareth, Small tire, oops, tyre pumps will fill a small air tank. The problem is how long it takes and the duty cycle of the pump. Some will have an extended duty cycle and can be used without stopping for it to cool down. The problem with all the small pumps is that they need to run the tiny piston up and down very fast in order to fill a tire in any reasonable length of time. This makes them noisy because the little DC motor is spinning so fast. Oh crap, I just re-read your message and it seems you are asking if the local gas station air compressor will be powerful enough to fill your tank. Here in the USA most gas station air compressors will be able to fill a portable air tank, but some to maybe only to 80 PSI or so. Some of the gas stations have a stand alone air compressor for filling tyres off away from the gas, er, petrol pumps and they tend to have undersized compressors so filling your tank may take a while. But they will fill it. I imagine that in the UK there are similar things since ti, um ,tyres are the same the world over no matter how you spell the name. I know some folks here will also use old beer kegs to hold compressed air. They are made from pretty heavy wall stainless steel. I have an old keg that I use for just this reason. Recently I modified a keg, converting it into a still for a new local micro distillery. The keg had stamped on it that it would burst if pressurized over 60 PSI. After putting some holes in it for various pipes I was able to measure the wall thickness and it would take more, something around 350 PSI, to burst it. I think there must be a lot of folks stealing kegs to use as air tanks. Cheers, Eric

Phil Allison <pallison49@gmail.com>: Mar 22 06:13PM -0700 Gareth Magennis wrote:     > I only want to blow the dust out of a power amplifier occasionally. > I can buy a can of air do do that, but it is expensive.   ** You are labouring under a misconception.   So called "air duster" is not air, but liquefied gas - normally a fluorocarbon.   This allows a small can to hold a useful amount of gas, about 200 litres. A bottle of compressed air would be hold only a few percent of that amount with rapidly diminishing pressure as it is used - IOW almost useless.   You need a continuous supply of compressed air for your tasks.   The usual way to clean a fluff & dust clogged power amps is with a vacuum cleaner and a soft brush. A damp cloth gets most of what is left over.   In cases of sticky contamination or carbon soot from a fire only disassembly and washing in warm water and detergent works.     .... Phil

Clifford Heath <no.spam@please.net>: Mar 23 09:32AM +1100 On 23/03/16 08:46, Gareth Magennis wrote: > I would really like a very small, cheap, air tank that I can charge > every now and again at the local garage (i.e. can be filled with a > standard car tyre pump).   A standard type of water-based fire extinguisher can be pressurized using air through a nozzle the same as a tyre nozzle. That is, you can fill it yourself and pressurize at the local fuel station. They have a pressure gauge so you can tell whether your extinguisher is ready for use.   I have a couple of these, and used one in a gas-flow experiment at 150PSI, no water. It will discharge through a 1mm nozzle for longer than 2 minutes. I have time/pressure graphs somewhere; that was the point of the experiment, we measured the speed of sound and calculated an approximation to absolute zero as a high-school experiment).   If you change the standard water nozzle for one with a smaller diameter, and don't mind reaching down to the cylinder to discharge it, you'd need no other changes.   My ones look like this: <http://www.gumtree.com.au/s-ad/sebastopol/miscellaneous-goods/9l-water-fire-extinguisher-refillable-50-each/1086145027>   Clifford Heath.

nutmeg3278@gmail.com: Mar 22 04:27PM -0700 Thanks Ron, speakers were "off." Not sure how kids managed to do that.

Top Cat <thomas.is.topcat@googlemail.com>: Mar 22 02:14PM -0700 I hope someone can help me.   I have an extremely old CRT attached to a Space Invaders B&W arcade cabinet. There is no available schematic, that I can find. The flyback has died but there is no modern replacement, mainly because the documentation for the historical model is non existent. So I dont know the input or output voltages, I have no circuit diagram, and I cannot find anything to determine what its input/output parameters can be. I do have the old flyback, I know the monitor size, and I have the actual circuit.   The model is marked as "Toei GM-140 TV MONITOR". It was produced around 1979; or from 1976 onwards.   My question is this: Can one retro/reverse engineer or somehow determine what modern equivalent could replace a flyback in this circumstance. Is this possible?   Cheers in advance.

dansabrservices@yahoo.com: Mar 22 02:22PM -0700 Any numbers at all on the flyback?

Top Cat <thomas.is.topcat@googlemail.com>: Mar 22 02:33PM -0700 > Any numbers at all on the flyback?   yes:   TF-1 Tj' 21 TOTOKU

Top Cat <thomas.is.topcat@googlemail.com>: Mar 22 02:48PM -0700 TF-1 Tj' 21 (This could be TJt 21) TOTOKU

captainvideo462009@gmail.com: Mar 22 02:12PM -0700 Thats interesting Jon. I'm going to look for that. Wouldn't have thought that such an old system would have recognized anything like that. And Jurb I too have never seen where you get dial tone back when someone hangs up. I think its purely theatrical. Lenny

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