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Madness <policedept@thedonutshop.com>: Nov 20 03:55PM -0500 Just acquired a bunch of these lamps. They're in the same mini-bayonet style as lamps like the #44/47. But would anyone know if these lamps can be connected directly to 120 volts? Or do they need a resistor, @ if so, what value?

Jon Elson <jmelson@wustl.edu>: Nov 20 03:02PM -0600 Madness wrote:   > style as lamps like the #44/47. But would anyone know if these lamps can > be connected directly to 120 volts? Or do they need a resistor, @ if so, > what value? Oh, you definitely need a series resistor. About 100K is typical.   Jon

"Ian Field" <gangprobing.alien@ntlworld.com>: Nov 20 10:08PM "Jon Elson" <jmelson@wustl.edu> wrote in message news:3_2dnQ8Xm6h3FNLLnZ2dnUU7-TednZ2d@giganews.com... >> be connected directly to 120 volts? Or do they need a resistor, @ if so, >> what value? > Oh, you definitely need a series resistor. About 100K is typical.   Of 3 hits from searching NE51 - voltage rating was stated variously from 105 - 120.   Confusingly, one page displayed a picture of a filament bulb.   If a "bunch" of them is sufficient to sacrifice one, I'd peel the base cap and see if there's a resistor in there.   Anything with a plastic lens cap probably has a resistor in the base.   Ionisation voltage is usually 70 - 90V, across the mains with a 100k resistor in series would reveal the volt drop of the bulb - anything much above 90V suggests an internal resistor.

M Philbrook <jamie_ka1lpa@charter.net>: Nov 20 05:44PM -0500 In article <n2o178$ktt$1@dont-email.me>, policedept@thedonutshop.com says... > style as lamps like the #44/47. But would anyone know if these lamps can > be connected directly to 120 volts? Or do they need a resistor, @ if so, > what value? That lamp is set to operate at 120V AC, so no, you don't need a resistor. I do think they may be putting one in the base.   A NE-2 however, does need a resistor.

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 20 06:03PM -0500 "M Philbrook" <jamie_ka1lpa@charter.net> wrote in message news:MPG.30b96c56bc3991bb989db0@news.eternal-september.org...   > That lamp is set to operate at 120V AC, so no, you don't need a > resistor. I do think they may be putting one in the base.   > A NE-2 however, does need a resistor.   While some neon bulbs with a base may not need an external resistor, this one needs an external resistor.   All the data sheets I looked at states they need an external resistor , usually a 220 K . http://www.bulbtown.com/B1A_NE_51_Neon_Glow_Bulb_BA9S_Base_p/b1a.htm

hrhofmann@att.net: Nov 20 08:14PM -0800 On Friday, November 20, 2015 at 2:55:22 PM UTC-6, Madness wrote: > style as lamps like the #44/47. But would anyone know if these lamps can > be connected directly to 120 volts? Or do they need a resistor, @ if so, > what value?   anywhere from 100,000 - 200,000 ohms, 1/2 watt or larger. Smaller resistor, brighter light, shorter bulb life.

Madness <policedept@thedonutshop.com>: Nov 20 11:34PM -0500 Thanks for the replies, everyone. I forgot to mention that my lot (about 30) is of vintage GE NE-51's, not the modern "NE-2 w/ plastic lens" variety.

Tim Schwartz <tim@bristolnj.com>: Nov 21 08:38AM -0500 On 11/20/2015 3:55 PM, Madness wrote: > style as lamps like the #44/47. But would anyone know if these lamps can > be connected directly to 120 volts? Or do they need a resistor, @ if so, > what value?     Hello,   While I recall that they need the dropping resistor, since you have a bunch of them, I might try destructive testing, and break one apart to see if there is an internal resistor or not.   Regards, Tim

Fred McKenzie <fmmck@aol.com>: Nov 21 10:12AM -0500 In article <n2o178$ktt$1@dont-email.me>, > style as lamps like the #44/47. But would anyone know if these lamps can > be connected directly to 120 volts? Or do they need a resistor, @ if so, > what value?   Madness-   NE-51 does NOT have a resistor inside!   One thing you can do with them, is build a relaxation oscillator. From a 90 to 100 volt DC source, connect a series resistor, with a capacitor across the bulb. Perhaps 470K Ohms and 1 uF. Try different values to change the flashing rate. For smaller values, it can be used as an audio oscillator.   Another variation is to have several bulbs, each with its series resistor. But the capacitors are connected from bulb to bulb in a ring. The result is a somewhat random flashing. I once built one with 5 generic neon lamps using two small 45 Volt batteries in series. Some people would become engrossed, trying to figure out the flashing sequence!   Fred

c4urs11 <c4urs11@domain.hidden>: Nov 21 03:32PM On Sat, 21 Nov 2015 10:12:31 -0500, Fred McKenzie wrote:   > For smaller values, it can be used as an audio oscillator.   I remember repairing a church organ that used such oscillators, one for each key... That was some 40 years ago :-) Sawtooth oscillators do produce a nice sound.   Cheers!

Michael Black <et472@ncf.ca>: Nov 21 10:47AM -0500

"jfeng@my-deja.com" <jfeng@my-deja.com>: Nov 21 08:01AM -0800 On Saturday, November 21, 2015 at 5:38:50 AM UTC-8, Tim Schwartz wrote: > see if there is an internal resistor or not.   > Regards, > Tim If you take this approach, it does not have to be destructive. If you own a soldering iron, you can melt the two solder blobs on the bayonet, loosen the cement, and remove the bulb intact. After inspection, you can reglue and resolder, and the lamp will be as good as new.

Cursitor Doom <curd@notformail.com>: Nov 21 01:24AM Hi all,     I'm looking to acquire a new LCR meter to replace the old bridges I've been formerly using, which can be a bit cumbersome. Can anyone recommend one from personal experience? I've watched all sorts of 'tear down' videos on YT but it's not clear if the people reviewing are involved in some way with the manufacturers and therefore biased, hence I'd like to hear from regular, independent users on their personal experience with these devices.   thanks,   CD

Dimitrij Klingbeil <nospam@no-address.com>: Nov 21 03:27PM +0100 On 21.11.2015 02:24, Cursitor Doom wrote: > I'm looking to acquire a new LCR meter to replace the old bridges > I've been formerly using, which can be a bit cumbersome. Can anyone > recommend one from personal experience?   I've been using an "LCR700" for a while now.   http://overseas.sanwa-meter.co.jp/items/detail.php?id=333   Frequencies: 100, 120 Hz, 1, 10, 100 kHz   Works well so far, can resolve single-digit milliohms ESR too (although for such low values one really needs to run the self-calibration just before making the measurement). Has limits at very high capacitances in the tens of thousands microfarads (where it can only measure ESR but not the capacitance itself). Battery life is ok, but not stellar. I would recommend taking the battery out of the meter when it's kept in storage for longer periods of time (and also to use rechargeable batteries).   Unfortunately quite expensive at official Sanwa overseas distributors, but at much more reasonable prices in online shops in Japan (even with package forwarder fees, import duties and taxes still basically 2/3 of the official distributor price here).   Regards Dimitrij

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 21 10:31AM -0500 "asdf" <asdf@nospam.com> wrote in message news:n2p7pg$r2i$1@speranza.aioe.org... > All reviews I read so far are very positive about their accuracy.   > Here is just one example, search for "lcr tester" to find more. > http://www.ebay.com/itm/252035832599   Ther is no real difference in the Peak meter and the other one off ebay other than the case. Many of the ones on ebay for around $ 15 to $ 25 test LCR and solid state devices where Peak tries to sell two seperate meters.   The one I bought off ebay a couple of years ago seems to work very well. I did put it in a plastic case. While not lab quality, it is good enough to test devices to see if they are close to their specified values or not any good at all.

asdf <asdf@nospam.com>: Nov 21 07:51AM On Sat, 21 Nov 2015 01:24:25 +0000, Cursitor Doom wrote:   > I'm looking to acquire a new LCR meter to replace the old bridges I've > been formerly using, which can be a bit cumbersome. Can anyone recommend > one from personal experience? I've watched all sorts of 'tear down'   I'm happy with this one purchased years ago.   http://www.peakelec.co.uk/acatalog/jz_lcr40.html   Today there are some really interesting and much cheaper multi purpose testers (transistor, lcr, esr etc.) on Ebay. All reviews I read so far are very positive about their accuracy.   Here is just one example, search for "lcr tester" to find more. http://www.ebay.com/itm/252035832599

Chuck <chuck@mydeja.net>: Nov 20 11:47AM -0600 On Fri, 20 Nov 2015 03:43:10 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:   >bought 20 years ago. I almost didn't buy it because I did't have a >digital camera and didn't expect to get one. Didn't get one for >another 10 years (and even it doesn't use an adapter like this.))   One of the capacitors that goes high esr and causes a power supply to die if it cools off doesn't show any physical deterioration. Usually 47uf 50V.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

mike <ham789@netzero.net>: Nov 20 09:50AM -0800 On 11/20/2015 12:43 AM, Micky wrote: > bought 20 years ago. I almost didn't buy it because I did't have a > digital camera and didn't expect to get one. Didn't get one for > another 10 years (and even it doesn't use an adapter like this.))   Bottom line...buy the new supply. Problem with that one is the plug on the end is different from most other router power supplies. Get the right one and be done with it.   I fix wall warts all the time for my own use. I'd never sell a gizmo with a power supply that I repaired. Too much liability involved.   Most fail with shorted input diodes, but that also blows the fuse. I've been fixing stuff for almost half a century, but working on line-connected stuff still scares the hell out of me...and I've got a completely isolated scope probe system. Even if you do find out what's broke, where are you gonna get the replacement part? Putting it back together is problematic. What happens if you try to unplug it and the glue breaks...you end up with AC in your hands...not fun.   Look at the risk/reward ratio. Best that can possibly happen is you save $7.50. Worst is electrocution? burning down your house? For stuff connected directly to the line, if you don't know what you're doing, keep it that way.

Jeff Liebermann <jeffl@cruzio.com>: Nov 20 01:03PM -0800 On Fri, 20 Nov 2015 03:43:10 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:   >What should I look at first?   Ummm... perhaps Google for "JTA0302 repair"? <http://hardware-today.com/articles/networking_hardware/how_to_repair_power_supply_adapter_d_link_5v_2a_jta0302d_e>   Drivel: Here's my collection: <http://802.11junk.com/jeffl/pics/repair/> with a few wall wart repairs. -- 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

Micky <NONONOmisc07@bigfoot.com>: Nov 20 05:46PM -0500 >One of the capacitors that goes high esr and causes a power supply to >die if it cools off doesn't show any physical deterioration. Usually >47uf 50V.   So you're suggesting there was no surge, but the lack of power let the PS cool off and the capacitor fail! I never would have thought of that. Also, you name the same cap that the url Jeff gave found was bad (along with the zener diode).   And you're right, it looks fine.

Micky <NONONOmisc07@bigfoot.com>: Nov 20 05:50PM -0500 On Fri, 20 Nov 2015 13:03:27 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >wrote:   >>What should I look at first?   >Ummm... perhaps   I recognize the sarcasm. ;-)   >Google for "JTA0302 repair"?   It never occurred to me to do that. Wow, the perfect page.   ><http://hardware-today.com/articles/networking_hardware/how_to_repair_power_supply_adapter_d_link_5v_2a_jta0302d_e>   That's it all right. A slightly different arrangment, but all the same parts.   And a schematic too! I have to spend a bunch of time looking at that. >Drivel: Here's my collection: ><http://802.11junk.com/jeffl/pics/repair/> >with a few wall wart repairs.   No kidding!   Thanks, and thanks all.

Jeff Liebermann <jeffl@cruzio.com>: Nov 20 03:20PM -0800 On Fri, 20 Nov 2015 17:50:23 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:   >On Fri, 20 Nov 2015 13:03:27 -0800, Jeff Liebermann <jeffl@cruzio.com> >wrote:   >I recognize the sarcasm. ;-)   I was on the phone with a very polite but useless support personality possibly in India. I hope you don't mind me taking out my frustrations on you.   >It never occurred to me to do that. Wow, the perfect page. >><http://hardware-today.com/articles/networking_hardware/how_to_repair_power_supply_adapter_d_link_5v_2a_jta0302d_e>   Yep. I usually don't get that lucky. I recently tried to repair one of those by replacing 3 of the caps mentioned. It didn't work. Of course, I didn't bother searching for info until after I had given up and recycled the power supply. Do like I say, not like I do.   >That's it all right. A slightly different arrangment, but all the >same parts.   There are A through E variations. I've only seen B and C which look like the same board layout, but built by different contractors. I don't know if there are any component value changes or schematic variations.   >And a schematic too! I have to spend a bunch of time looking at that.   You should be able to get some theory of operation in the data sheets and app notes for the UC3843B chip: <https://www.google.com/search?q=uc3843b> <http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/CD00003930.pdf>   >><http://802.11junk.com/jeffl/pics/repair/> >>with a few wall wart repairs.   >No kidding!   I don't know why I bother trying to fix those. It's certainly not making me any money. Worse, I've accumulated a fairly large collection of wall warts that really need to be recycled instead of occupying space.   "One day, son, all of these perfectly good A.C. adapters, which have long outlived the products they were originally designed for, will be yours." <http://www.newyorker.com/wp-content/uploads/2012/01/120116_a16285_g2048-600.jpg>   -- 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

M Philbrook <jamie_ka1lpa@charter.net>: Nov 20 06:26PM -0500 In article <mk6v4bpocom5vgak3obft2occj3cua1961@4ax.com>, NONONOmisc07 @bigfoot.com says... > >with a few wall wart repairs.   > No kidding!   > Thanks, and thanks all.   Its amazing how you guys can find schematics to these things.   I would check the primary side of the transformer, make sure it didn't get opened from a latch on.   Also check that little blue thingy that is attached to the line fuse feeding the common choke. You may need to do that under power via a volt meter.   Have fun.   Jamie

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