sci.electronics.repair@googlegroups.com

Google Groups

Jim Horton <jhorton@nospam.net>: Oct 30 12:05PM -0400 Mainly from Rick's kind encouragement regarding using wax for potting, I picked up a spare pair of HEI coils from the junk yard yesterday. I decided to pot this pair in the leftover paraffin I had from my recent potting/ depotting. This time I did not fill completely to the top and left about an inch of space. Once the wax started to harden and leave a "well" in the center, I then topped off with some remaining hot wax. Once completely dried and cooled today, there was still a well, but very small and of no concern.   There was the capacitor/ resistor series combination I asked about prior. Still not sure what they are for, I went ahead and added them to this pair too, but I did it after the wax potting by leaving some target leads above the wax so the parts could be soldered. After confirming everything working, I covered and surrounded the RC's with high voltage tape.   I can only guess about the RC circuit. It was probably something someone recommended adding to my original circuit. It's purpose might have been as an interference filter, or maybe to drain the circuit when off so that one is not shocked from the possible stored charge in the capacitors.   Anyway, it's working great! The hardest part, and I must have forgotten about this, was getting solder to stick to the HV output terminals of the HEI coils! It took my 240 watt iron to do it, and even then it took a while for the heating to reach optimum.   This paraffin has a melting temperature of 130 F. No additives, easily melted in a double boiler. I did go with another 6x6x4 junction box after first trying a similar sized polypropylene dollar store container. While trying to punch holes in the side for the low voltage primary leads, the entire container cracked on that side. I tried gluing it with hot glue, but the moment the wax hit that, it went right through. Thank goodness for the aluminum tray underneath! With the junction box, although more expensive, JB Quik Weld has the primary feedthroughs cured well enough within 2 hours to hold up to wax and oven heat. I did not bring the HV TV wire leads out the side this time and had them exit at the top. Seems to work fine with no unwanted arcing. I did not cover over the top with the junction box cover, just made sure the wax filled it up.   I also made a solder smoke remover out of a Youtube video I saw using a plastic container, PC fan, and blue evaporative cooling filter you cut yourself. You wet the filters, activate the fan and go. It would be easy to add an activated charcoal layer, but I didn't this time as all I was working with was standard solder. Seemed to do the job although you have to be within about 6" with the circuit or iron for it to draw in the smoke.

Jim Horton <jhorton@nospam.net>: Oct 30 12:07PM -0400 Mainly from Rick's kind encouragement regarding using wax for potting, I picked up a spare pair of HEI coils from the junk yard yesterday. I decided to pot this pair in the leftover paraffin I had from my recent potting/ depotting. This time I did not fill completely to the top and left about an inch of space. Once the wax started to harden and leave a "well" in the center, I then topped off with some remaining hot wax. Once completely dried and cooled today, there was still a well, but very small and of no concern.   There was the capacitor/ resistor series combination I asked about prior. Still not sure what they are for, I went ahead and added them to this pair too, but I did it after the wax potting by leaving some target leads above the wax so the parts could be soldered. After confirming everything working, I covered and surrounded the RC's with high voltage tape.   I can only guess about the RC circuit. It was probably something someone recommended adding to my original circuit. It's purpose might have been as an interference filter, or maybe to drain the circuit when off so that one is not shocked from the possible stored charge in the capacitors.   Anyway, it's working great! The hardest part, and I must have forgotten about this, was getting solder to stick to the HV output terminals of the HEI coils! It took my 240 watt iron to do it, and even then it took a while for the heating to reach optimum.   This paraffin has a melting temperature of 130 F. No additives, easily melted in a double boiler. I did go with another 6x6x4 junction box after first trying a similar sized polypropylene dollar store container. While trying to punch holes in the side for the low voltage primary leads, the entire container cracked on that side. I tried gluing it with hot glue, but the moment the wax hit that, it went right through. Thank goodness for the aluminum tray underneath! With the junction box, although more expensive, JB Quik Weld has the primary feedthroughs cured well enough within 2 hours to hold up to wax and oven heat. I did not bring the HV TV wire leads out the side this time and had them exit at the top. Seems to work fine with no unwanted arcing. I did not cover over the top with the junction box cover, just made sure the wax filled it up.   I also made a solder smoke remover out of a Youtube video I saw using a plastic container, PC fan, and blue evaporative cooling filter you cut yourself. You wet the filters, activate the fan and go. It would be easy to add an activated charcoal layer, but I didn't this time as all I was working with was standard solder. Seemed to do the job although you have to be within about 6" with the circuit or iron for it to draw in the smoke.

John-Del <ohger1s@gmail.com>: Oct 30 04:48AM -0700 On Wednesday, October 30, 2019 at 12:53:20 AM UTC-4, John Robertson wrote:   > > NT   > Manufacturers tech support via email/web site?   > John   He can try, but I've found out over the years that manufacturers almost never divulge any information.   Early this summer I repaired an AC inverter module for a solar array for an old customer (and he asked nicely). The inverter is an $800 dollar item but when I contacted the manufacturer for a schematic, the engineer told me it was "proprietary". I told him AC inverters are not a unique product and all the ICs in the inverter were off the shelf sourced, but it fell on deaf ears. Fortunately, this one was stone dead and using the suggested circuits from the IC data sheets found on line, I was able to find the problem in a DC-DC circuit.   I would be very surprised if the scooter manufacturer offered anything but a rebate or exchange program.

tabbypurr@gmail.com: Oct 30 05:38AM -0700 On Wednesday, 30 October 2019 11:48:41 UTC, John-Del wrote:   > He can try, but I've found out over the years that manufacturers almost never divulge any information.   > Early this summer I repaired an AC inverter module for a solar array for an old customer (and he asked nicely). The inverter is an $800 dollar item but when I contacted the manufacturer for a schematic, the engineer told me it was "proprietary". I told him AC inverters are not a unique product and all the ICs in the inverter were off the shelf sourced, but it fell on deaf ears. Fortunately, this one was stone dead and using the suggested circuits from the IC data sheets found on line, I was able to find the problem in a DC-DC circuit.   > I would be very surprised if the scooter manufacturer offered anything but a rebate or exchange program.   Mfrs say go to your local dealer, have them do any work. I suspect they're scared of liability as well as looking to steam what they can out of everyone. Local dealer was approached once previously, and they wanted hundreds for a job a local eng firm quoted £60 for. Not a path of any use.     NT

tabbypurr@gmail.com: Oct 30 05:39AM -0700 On Wednesday, 30 October 2019 11:00:42 UTC, Adrian Tuddenham wrote: > properly and had gradually worked loose. Perhaps the speed control > connections were the first to go open circuit or perhaps Code 7 was the > first thing the error code software picked up on.   Maybe that's it, the throttle isn't zeroing right either. I'll go look at that later on. Thanks.     NT

Stephen Wolstenholme <steve@easynn.com>: Oct 30 01:01PM >Mfrs say go to your local dealer, have them do any work. I suspect they're scared of liability as well as looking to steam what they can out of everyone. Local dealer was approached once previously, and they wanted hundreds for a job a local eng firm quoted £60 for. Not a path of any use.   >NT   I have the same experience with my wife's scooter. The local dealer charges too much. The man who does anything that involves the replacement of any parts seems to have access to anything that the local dealer stocks but charges much less.   Steve -- http://www.npsnn.com

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Oct 30 01:16PM > > first thing the error code software picked up on.   > Maybe that's it, the throttle isn't zeroing right either. I'll go look at > that later on. Thanks.   There's probably a safety check in the startup routine to make sure power can't be applied if the 'throttle' is already open . Forklift trucks ran all sorts of tests like that (using relay logic in the older models) before they would close the main contactor.   -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

Tim Schwartz <tim@bristolnj.com>: Oct 26 05:25PM -0400 Hi,   The D40D5 is an obsolete case style, but a TO-220 transistor can be used though the pin out may be different. The specs for the D40D5 are here:   https://pdf1.alldatasheet.com/datasheet-pdf/view/130481/ETC1/D40D5.html   Many common TO-220 devices will work, like a TIP-41C or a BD-911. You may have to put sleeving on the leads and twist them around to the correct hole, depending on the board.   It would be helpful if you mentioned what product you are working on, as you might get better advice.   Regards, Tim     On 10/25/2019 7:34 PM, TheExperimenter wrote:

TheExperimenter <theexp8712@noaol.net>: Oct 26 05:38PM -0400 On 10/26/19 5:25 PM, Tim Schwartz wrote: > on, as you might get better advice.   > Regards, > Tim   Ok, I'll try it here too. I posted this in another group and finally reluctantly shared what it was for to be met with almost instant criticism, but here we go (I'm just quoting what I wrote in the other group):   Unfortunately, the exact schematic does not appear online and is copyrighted. However, it appeared in Radio Electronics Magazine September 1986, p. 42 stun gun. A similar one adapted from the article is here, but does not use the same components:   http://www.learningelectronics.net/VA3AVR/circ/hv/stungun/stungun.html   I built the gun from the kit in 1994, but my wife used it a month ago and burned it out while scaring off a would be attacker.   I originally contacted the firm that made it, but have not heard back after several weeks, so I went parts looking myself. I don't trust the ones with the puny "400 KV" modules that seem to be front and center now. This one really worked and was tested scientifically at the time which is why I'd like to get the replacement components.

Chris <cbx@noreply.com>: Oct 26 09:49AM On Sat, 26 Oct 2019 00:33:57 -0400, Jim Horton wrote:   > Just wanted to share the demo for the spark generator in its new > housing. The sparks you see are about 110 mm.   Is it FCC compliant?

Cursitor Doom <curd@notformail.com>: Oct 27 05:58PM On Sun, 27 Oct 2019 08:35:01 -0500, Fox's Mercantile wrote:     > You mean you've never heard of it. > In the words of Jon Stewart, "You can look this shit up you know."   > <https://en.wikipedia.org/wiki/Oudin_coil>   Obviously. But what I said still stands. Everyone's at least *heard of* Tesla coils even if they don't know what they are.           -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Jim Horton <jhorton@nospam.net>: Oct 27 03:22PM -0400 On 10/27/19 1:58 PM, Cursitor Doom wrote:   >> <https://en.wikipedia.org/wiki/Oudin_coil>   > Obviously. But what I said still stands. Everyone's at least *heard of* > Tesla coils even if they don't know what they are.   Actually, the so-called "violet ray" device I have and a "Tesla" coil I used to have were both made by Electro Technic. Both devices used almost the same components throughout which consisted of an adjustable vibrator/ kicker which drove a resonant coil/ capacitor. The only difference was in the main coils: the hand held vacuum checker (aka violet ray) used a wax/ epoxy potted coil whereas their "Tesla" coil used a single air coil would around a plastic form. Both of the devices operated on identical frequencies and would give a slight shock/ burn, but neither were dangerous. In fact, I built their portable Tesla coil myself year ago, using both parts from them and ones I had lying around. I still have all the parts to build another someday as I sold the original. And I have several of the hand held coils in my drawers. Only one is assembled, but there are parts for others. I always considered them as close to "safe" as anyone was going to get because the 2" sparks really are weak just in case kids or others decide to touch one (and they have plenty of times!). My spark generator device I recently rehoused though is a different animal entirely. You definitely DON'T want any of the direct sparks touching you. Even when I'm struck with the weaker sparks through the HV tv wire, I really feel it. So, other than for demos and me using the device the entire time, no one gets around it.   Now I should point out that my Electro Technic coils and parts are not that old and it's quite possible that original, antique violet ray devices used a different set up as I've never come across one to investigate for sure.

John-Del <ohger1s@gmail.com>: Oct 30 04:53AM -0700 On Tuesday, October 29, 2019 at 5:05:53 PM UTC-4, Ralph Mowery wrote:   > > Links please.   > Are you sure it is a spike or is it possiable the refrigerator is > drawing enough current to drop the voltage ?   That was my first thought - wiring issue.

Cursitor Doom <curd@notformail.com>: Oct 25 09:40PM On Fri, 25 Oct 2019 21:36:51 +0000, Cursitor Doom wrote:   Let's try and make that clearer:   Q10: Vc +1.1v, Vb +0.5v, Ve +1.2v   Q9: Vc -3.2v, Vb +1.1v, Ve -1.34v (this is the faulty one)   Q8: Vc -3.8v, Vb -3.2v, Ve -3.9v       Q15: Vc -2v, Vb +0.11v, Ve +0.78v   Q14: Vc -7.74v, Vb -2v, Ve -1.34v   Q13: Vc +3.5v, Vb -7.74v, Ve -7v

Fred McKenzie <fmmck@aol.com>: Oct 25 04:35PM -0400 In article <qov5uu$thh$1@dont-email.me>, > ways! Double checking on the resistance range confirmed 600 ohms between > C and E both ways. I've never known a BJT fail in *this* way. Has anyone > else?   CD-   That sounds like leakage to me. Did you measure C, B and E voltages in-circuit?   I wonder if a coupling capacitor from the previous stage is leaking, and it might have damaged that transistor?   Fred

Ralph Mowery <rmowery28146@earthlink.net>: Oct 25 11:29PM -0400 In article <h1hsj2F7jmkU1@mid.individual.net>, trevor@rageaudio.com.au says...   > **Frequently. Invest in a PEAK transistor tester. It will save time and > heartache.   Instead of investing in the PEAK, go to ebay and get one of the component testers for about $ 15 to $ 25.   About the same as the Peak and one box tests solid state and passive components where Peak sells 2 boxes to do the same thing.

Andy Burns <usenet@andyburns.uk>: Oct 25 08:49AM +0100 Phil Allison wrote:   > Piss off nutcase.   I suggest upping your medication ...

Andy Burns <usenet@andyburns.uk>: Oct 25 07:42AM +0100 Phil Allison wrote:   > seems many folk are addicted to buying on-line these day but forget about the different power systems in the USA and Japan compared to the rest of the planet.   > Twice recently, I have been given instrument amplifiers with IEC 3-pin inlets   you mean a C14 inlet presumably?   > that are wired for 120VAC, 60Hz power. > One blew up soon as the owner plugged it in.   I'm wondering why an average USA user would even /have/ a lead kicking around from a 240V outlet to C13 trailing plug? I mean that such a lead is rated only for 10A, so a high power appliance (typically tumble dryers and ovens?) would be more likely to be hard-wired, or perhaps use a C19/C20 connector.

Andy Burns <usenet@andyburns.uk>: Oct 25 08:00AM +0100 Phil Allison wrote:   > Whose barking mad idea was it for the US to adopt a 240VAC Euro supply connector ???   There's nothing fundamentally "euro" about IEC connectors, most of the planet manages to produce equipment that's 120V/240V agnostic.   <https://en.wikipedia.org/wiki/International_Electrotechnical_Commission#/media/File:IEC_membership.png>

vjp2.at@at.BioStrategist.dot.dot.com: Oct 24 10:54PM Thanks. I though it was wierd. New bulb. It has like a circle of little dots of light which take a bit to shut down. In my mind LEDs should be the fastest to shut down. I am deathly afraid of halogen because of fires and I keep wondering if I got halogen instead.     - = - Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus blog: panix.com/~vjp2/ruminatn.htm - = - web: panix.com/~vjp2/vasos.htm facebook.com/vasjpan2 - linkedin.com/in/vasjpan02 - biostrategist.com ---{Nothing herein constitutes advice. Everything fully disclaimed.}---

You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com.