Post by thread:[EE]: build UV eeprom eraser

Hi everyone, I decided to build a UV eeprom eraser instead of purchasing one at inflated prices here in Australia. ($100 US) Turned out to be VERY easy, I got the UV germicidal tube, G4T5 (4w 5" tube) for $13 US at the local electronics store. I got a 4w "childrens nightlight" which runs directly from 240vac mains, from a K-mart type store for $9 US. It had a F4T5 white tube. The tubes are interchangable, so I have a mains powered 4w UV eraser for $22 US. If anyone is interested, I pulled the nighlight apart to see what was inside and was *intrigued* to find there are no active or expensive parts in it. No transistors, no coils, no transformers etc. It has 2 small resistors, 2 diodes, 2 small mylar style caps. Very cheap and easy to assemble. It doesn't even need the heater elements in the tube, just uses one pin at each end so it will work fine even on a tube with blown heater filament. If someone wants the circuit I can reverse engineer it and put up a circuit diagram. It interested me anyway, I was just about to design an inverter circuit to power the 4w tube but someone found a much simpler solution to me!! :o) -Roman -- http://www.piclist.com hint: To leave the PICList spam_OUTpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

Roman: Please do reverse engineer it for us. In trade, I will give you the reverse engineered info for an LED traffic light. My friend Al Brown did this. Al did a lot of work to get the schematic since there were 180 LED's in the circuit. Note to James Newton: What is the preferred method of posting a schematic? Is a PDF attachment proper? What maximum size is acceptable? -- Rich Roman Black wrote: {Quote hidden}> > Hi everyone, I decided to build a UV eeprom eraser > instead of purchasing one at inflated prices here in > Australia. ($100 US) > > Turned out to be VERY easy, I got the UV germicidal > tube, G4T5 (4w 5" tube) for $13 US at the local > electronics store. > > I got a 4w "childrens nightlight" which runs directly > from 240vac mains, from a K-mart type store for $9 US. > It had a F4T5 white tube. > The tubes are interchangable, so I have a mains powered > 4w UV eraser for $22 US. > > If anyone is interested, I pulled the nighlight apart > to see what was inside and was *intrigued* to find > there are no active or expensive parts in it. No > transistors, no coils, no transformers etc. It has > 2 small resistors, 2 diodes, 2 small mylar style > caps. Very cheap and easy to assemble. It doesn't > even need the heater elements in the tube, just uses > one pin at each end so it will work fine even on a > tube with blown heater filament. > > If someone wants the circuit I can reverse engineer > it and put up a circuit diagram. It interested me > anyway, I was just about to design an inverter > circuit to power the 4w tube but someone found a > much simpler solution to me!! :o) > -Roman > > -- > http://www.piclist.com hint: To leave the PICList > .....piclist-unsubscribe-requestKILLspam@spam@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestKILLspammitvma.mit.edu

>Hi everyone, I decided to build a UV eeprom eraser >instead of purchasing one at inflated prices here in >Australia. ($100 US) :oO Neither in Brazil an eprom eraser is so expensive!!! >Turned out to be VERY easy, I got the UV germicidal >tube, G4T5 (4w 5" tube) for $13 US at the local >electronics store. Expensive too! There you can find these bulbs at around $5, for a tube with 15" >If anyone is interested, I pulled the nighlight apart >to see what was inside and was *intrigued* to find >there are no active or expensive parts in it. No >transistors, no coils, no transformers etc. It has >2 small resistors, 2 diodes, 2 small mylar style >caps. Very cheap and easy to assemble. It doesn't >even need the heater elements in the tube, just uses >one pin at each end so it will work fine even on a >tube with blown heater filament. THIS is interesting. What about the lifetime of bulb? I'd love to see this thing working, hehehehehe -- http://www.piclist.com hint: To leave the PICList .....piclist-unsubscribe-requestKILLspam.....mitvma.mit.edu

ALL it is, is a flourescent light, with a different tube. All you need, is a starter and ballast appropriate for the tube, and I'd prefer a safety switch on the door/lid/whatever, and a timer. Timer switches are available, for energy-savings on lighting, as standard home/industrial lighting items. -- Dave's Engineering Page: http://www.dvanhorn.org Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu

The amount of data that can be attached is limited, but I don't remember what the limit is... It was the number of lines of attached data in its encoded format rather than the size of the file before attachment so it may be hard to tell... Mike has the details on that... The best thing to do is upload it to a web server and then post a link Email it to me privately at jamesnewtonspam_OUTpiclist.com if you like and I will post it on piclist.com James Newton, PICList Admin #3 @spam@jamesnewtonKILLspampiclist.com 1-619-652-0593 phone http://www.piclist.com {Original Message removed}

part 0 51 bytes ies ist eine mehrteilige Nachricht im MIME-Format. part 1 1884 bytes content-type:text/plain; charset=us-ascii (decoded 7bit) "Alexandre Domingos F. Souza" wrote: > > >If anyone is interested, I pulled the nighlight apart > >to see what was inside and was *intrigued* to find > >there are no active or expensive parts in it. No > >transistors, no coils, no transformers etc. It has > >2 small resistors, 2 diodes, 2 small mylar style > >caps. Very cheap and easy to assemble. It doesn't > >even need the heater elements in the tube, just uses > >one pin at each end so it will work fine even on a > >tube with blown heater filament. > > THIS is interesting. What about the lifetime of bulb? I'd love to see this thing working, hehehehehe Quite a while ago, I bought a similar one here in germany. I used it to build - an eprom eraser! And I too was much to interested to leave it unopened :-). These units use the fact that the small 4W tubes don't have the same high ignition voltage than the big, long tubes. The big tubes use (better: used) an inductor in series to limit the current and to produce the ignition voltage together with a small neon tube - the starter. In the unit I bought the inductance is replaced by a cap which provides the same current limiting. To ignite the tube there is a simple sort of peak voltage doubler which gives 650V (at 230V mains), which is enough for this small tube (in most cases...). The main disadvantage: The doubled voltage to ignite the tube is not enough in every case. It happened to me that I switched the unit on and nothing happened - until I touched the tube. I don't expect the tube to ignite at low temperatures, either. And because eagle is already running, I have drawn the following short schematic, ripped from my unit when I examined it. So sad that I don't have use for more 4W tubes, so I haven't yet cloned this device ;-) Florian part 2 23959 bytes content-type:application/pdf; (decode) part 3 105 bytes -- http://www.piclist.com hint: To leave the PICList KILLspampiclist-unsubscribe-requestKILLspammitvma.mit.edu

At 05:37 PM 5/6/01 -0300, Alexandre Domingos F. Souza wrote: > >And because eagle is already running, I have drawn the following short > >schematic, ripped from my unit when I examined it. So sad that I don't > >have use for more 4W tubes, so I haven't yet cloned this device ;-) > > Very interesting! But will not work for - example - 10 watt > bulbs? What about 110V, that is the mains in Brazil? Use 10W ballast and starter from a cheap desk lamp or fishtank light. -- Dave's Engineering Page: http://www.dvanhorn.org Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -- http://www.piclist.com hint: To leave the PICList spamBeGonepiclist-unsubscribe-requestspamBeGonemitvma.mit.edu

>> This is the easy way, but I'm looking for learning new things :o) >I hear you. >I want to learn too, but not how to build eprom erasers. :) Sure! But what about a new type of ballast, lots CHEAPER than the ones used today (does in USA people use electronic balasts? Here we have it a lot!). Always an oportunity to learn and - who knows - put some buckets in the wallet :o) -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestEraseME.....mitvma.mit.edu

>> >Use 10W ballast and starter from a cheap desk lamp or fishtank light. >> This is the easy way, but I'm looking for learning new things :o) >I hear you. >I want to learn too, but not how to build eprom erasers. :) Talking about "how to build eprom erasers", I remembered a funny thing... The year was around 1993. Maybe 94. I got my first apple II (it was a Brazilian clone of the ][+), with one disk drive (that couldn't write a disk - there was a chip broken, and it was so expensive I couldn't afford it) and I exchanged my MSX (it was EXPENSIVE at these times) for an IC TEST Board for the apple, and an Eprom programmer. Funny, it could program only 2716/32/64, and I hacked to program 128. You couldn't even select the proper vpp voltage in the program, you should give some "turns" in a multiturn pot in the board. More archaic, impossible :o) Even with that, I couldn't program EPROMs, 'cause I hadn't an eprom eraser. As "the need is the mother of all inventions" I started to think how could I do that, and found a way, with a transformer (to get 220V), a voltage doubler and a mains lamp. As the element to gimme ultraviolet, I remembered there was a kind of lamp - mercury vapour, if I'm not mistaken - that worked almost like a fluorescent lamp - but there was a "bulb" inside of it, that emitted UV, and the white coating of the external glass, turned that in visible light. So I got everything togheter, and built my first eprom eraser. It worked like a charm, could erase only 3 or 4 EPROMs at time, but it was better (wow, how better!!!) than absolutely nothing. Comercial eprom erasers costed a lot that days. Nowadays I have an industrial eraser, that comport 40 eproms at time. But I used the "poor Alexandre eprom eraser" until 1998, when I got this new eraser. And it's still working!!! I gave it to a friend of mine, and he uses it until today! Of course it's cheap to get a lamp, a ballast and a box now and do your own deccent eprom eraser. But that one works, and he needs nothing more than that. It's nice to remember that, because someone in this list, I'm sure, will use this simple knowledge (the eprom eraser we were talking) to do something great, at least to him. And that brings to my mind: Even the smallest knowledge, can be all the diference for the right man. -- http://www.piclist.com hint: To leave the PICList RemoveMEpiclist-unsubscribe-requestspam_OUTKILLspammitvma.mit.edu

> > It's nice to remember that, because someone in this list, I'm > sure, will use this simple knowledge (the eprom eraser we were talking) > to do something great, at least to him. And that brings to my mind: Even > the smallest knowledge, can be all the diference for the right man. All I'm saying, is that to me, the eraser is a tool. I use it to do other things. The other things are where I'd rather spend my limited time. -- Dave's Engineering Page: http://www.dvanhorn.org Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -- http://www.piclist.com hint: To leave the PICList RemoveMEpiclist-unsubscribe-requestTakeThisOuTspammitvma.mit.edu

part 1 1017 bytes content-type:text/plain; charset=us-ascii (decoded quoted-printable) James Newton wrote: > The amount of data that can be attached is limited, but I don't remember > what the limit is... It was the number of lines of attached data in its > encoded format rather than the size of the file before attachment so it may > be hard to tell... Mike has the details on that... The size limit on attachments is 1000 lines after any encoding that your emailer does. I'm not quite sure what that works out to in actual file size, though. I keep meaning to try and work that out. Like James said in the part of the message that I snipped, the best solution for large files is post the file to a web server (and there's *lots* of free servers out there) and then post the URL to the list. -- Mike Werner KA8YSD | He that is slow to believe anything and | everything is of great understanding, '91 GS500E | for belief in one false principle is the Morgantown WV | beginning of all unwisdom. part 2 233 bytes content-type:application/pgp-signature (decode) part 3 154 bytes -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

On Sun, 6 May 2001 18:17:55 -0500, you wrote: >> >> It's nice to remember that, because someone in this list, I'm >> sure, will use this simple knowledge (the eprom eraser we were talking) >> to do something great, at least to him. And that brings to my mind: Even >> the smallest knowledge, can be all the diference for the right man. > >All I'm saying, is that to me, the eraser is a tool. >I use it to do other things. Exactly, I don't make my own pliers, or make paper to print on. But sometimes improvisation CAN be fun. > >The other things are where I'd rather spend my limited time. >-- >Dave's Engineering Page: http://www.dvanhorn.org >Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -------------------------- He Who Laughs Last Thinks Slowest. ------------------------------------ -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Richard Ottosen wrote: > > Roman: > > Please do reverse engineer it for us. > > In trade, I will give you the reverse engineered info for an LED traffic > light. My friend Al Brown did this. Al did a lot of work to get the > schematic since there were 180 LED's in the circuit. Hi Richard, sounds great. :o) I will get the schematic and put it up with a couple of photos on my web page tonight. -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

David VanHorn wrote: > > ALL it is, is a flourescent light, with a different tube. > > All you need, is a starter and ballast appropriate for the tube, and I'd > prefer a safety switch on the door/lid/whatever, and a timer. Ha ha! I'm not afraid of building a flourescent light. :o) Have you found a good source for obtaining 4w ballasts?? And micro 2-pin fittings for a 4w tube? That's why I just bought a cheap 4w nightlight from the supermarket. The part that I thought intriguing was that it doesn't use a ballast or even a starter for that matter. And no "electronic" ballast. Just 2 caps, 2 resistors and one cheap diode. Can't get better than that. ;o) > Timer switches are available, for energy-savings on lighting, as standard > home/industrial lighting items. They are normally 24-hour timers. Better timers come from small microwave ovens, 0-60min countdown timers. :o) -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> >Ha ha! I'm not afraid of building a flourescent light. :o) >Have you found a good source for obtaining 4w ballasts?? >And micro 2-pin fittings for a 4w tube? That's why I just >bought a cheap 4w nightlight from the supermarket. Ballasts and starters from Fishtank light, Old desk light. Sockets from same, or from battery flourescents. >The part that I thought intriguing was that it doesn't >use a ballast or even a starter for that matter. And >no "electronic" ballast. Just 2 caps, 2 resistors and >one cheap diode. Can't get better than that. ;o) Someone else commented that this start method isn't real reliable. I'd be pissed after a couple rounds of expecting erased parts and not getting them. >They are normally 24-hour timers. Better timers come >from small microwave ovens, 0-60min countdown timers. :o) Not so. I've seen them in 0-60 min, and 0-8 hours. The microwave offers a novel approach though. If you can get the microwaves to excite the nitrogen, then you'll get plenty of UV. You MAY need an EMI shield over the EPROMs though :) -- Dave's Engineering Page: http://www.dvanhorn.org Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Florian Voelzke wrote: {Quote hidden}> "Alexandre Domingos F. Souza" wrote: > > THIS is interesting. What about the lifetime of bulb? I'd love to see this thing working, hehehehehe > > Quite a while ago, I bought a similar one here in germany. I used it to > build - an eprom eraser! And I too was much to interested to leave it > unopened :-). > These units use the fact that the small 4W tubes don't have the same > high ignition voltage than the big, long tubes. The big tubes use > (better: used) an inductor in series to limit the current and to produce > the ignition voltage together with a small neon tube - the starter. > In the unit I bought the inductance is replaced by a cap which provides > the same current limiting. To ignite the tube there is a simple sort of > peak voltage doubler which gives 650V (at 230V mains), which is enough > for this small tube (in most cases...). > The main disadvantage: The doubled voltage to ignite the tube is not > enough in every case. It happened to me that I switched the unit on and > nothing happened - until I touched the tube. I don't expect the tube to > ignite at low temperatures, either. > And because eagle is already running, I have drawn the following short > schematic, ripped from my unit when I examined it. So sad that I don't > have use for more 4W tubes, so I haven't yet cloned this device ;-) Hi Florian, yes that circuit looks very similar to the light I bought. Mine doesn't have the two 68ohm series resitors to the tube, but instead has the wires 8 inches long. Probably a cheaper way of keeping the RF down. The capacitor and resistor values are slightly different, but the circuit is essentially the same operation. Just a note, there is a very important component, a copper foil stripe that runs the length of the tube and is attached to one tube wire. This is vital to start the tube and is the reason yours doesn't start until your finger touches the tube. Mine starts fine, and quickly, even when quite cold. These foil stripes are often used in cheap inverter fluoros. :o) -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

>Ha ha! I'm not afraid of building a flourescent light. :o) >Have you found a good source for obtaining 4w ballasts?? >And micro 2-pin fittings for a 4w tube? That's why I just >bought a cheap 4w nightlight from the supermarket. And it's nice to remember that sometimes is way cheaper to buy a complete product, than it's parts! >The part that I thought intriguing was that it doesn't >use a ballast or even a starter for that matter. And >no "electronic" ballast. Just 2 caps, 2 resistors and >one cheap diode. Can't get better than that. ;o) I will ressearch into this...maybe I can use it with a 10 watt bulb :o) >They are normally 24-hour timers. Better timers come >from small microwave ovens, 0-60min countdown timers. :o) BTW these are nice circuits to dig around! Microwave boards are cheap and have lots of interesting components, even hi power relays and a clock!!! -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

>> element to gimme ultraviolet, I remembered there was a kind of lamp - mercury vapour, if I'm not mistaken - that worked almost like a fluorescent lamp - but there was a "bulb" inside of it, that emitted UV, and the white coating of the external glass, turned that in visible light. << Flourescent lamps ARE mercury vapor lamps. These all work by electrically exciting the mercury atoms. At the right temperature and pressure, a mercury vapor is quite efficient at converting the electrical energy into UV radiation. A normal white-light flourescent lamp has a phosphor coating on the inside of the glass. The UV from the mercury excites the phosphor, which re-radiates the energy in the visible range. UV lamps for prom erasers and germ killing use the UV directly from the mercury vapor. The bulb has to be made of quartz instead of ordinary glass because glass will absorb most of the UV. Quartz is still mostly transparent at the mercury UV wavelength. Personally I'd rather pay for a UV prom eraser with a proper safety interlock. The UV coming from a quartz mercury vapor lamp is ionizing radiation. This is serious business. It can damage eyes and other things. ******************************************************************** Olin Lathrop, embedded systems consultant in Littleton Massachusetts (978) 742-9014, olinSTOPspamspam_OUTembedinc.com, http://www.embedinc.com -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

i built a four hour timer :-) http://www.qsl.net/n1yew Andy ----- Original Message ----- From: "Roman Black" <spamBeGonefastvidSTOPspamEraseMEEZY.NET.AU> To: <KILLspamPICLISTspamBeGoneMITVMA.MIT.EDU> Sent: Monday, May 07, 2001 4:03 AM Subject: Re: [EE]: build UV eeprom eraser {Quote hidden}> David VanHorn wrote: > > > > ALL it is, is a flourescent light, with a different tube. > > > > All you need, is a starter and ballast appropriate for the tube, and I'd > > prefer a safety switch on the door/lid/whatever, and a timer. > > Ha ha! I'm not afraid of building a flourescent light. :o) > Have you found a good source for obtaining 4w ballasts?? > And micro 2-pin fittings for a 4w tube? That's why I just > bought a cheap 4w nightlight from the supermarket. > > The part that I thought intriguing was that it doesn't > use a ballast or even a starter for that matter. And > no "electronic" ballast. Just 2 caps, 2 resistors and > one cheap diode. Can't get better than that. ;o) > > > > Timer switches are available, for energy-savings on lighting, as standard {Quote hidden}> > home/industrial lighting items. > > They are normally 24-hour timers. Better timers come > from small microwave ovens, 0-60min countdown timers. :o) > -Roman > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads