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Cursitor Doom <curd@notformail.com>: Oct 25 03:56PM So I've had to pull 6 transistors one by one out of this amplifier board, in the strong suspicion at least one of them was faulty. They all tested fine - until the last one (typical!). Anyway, these are small signal PNP BJTs in TO-8 tin cans. The last one checks out fine for base-emitter and base-collector junctions giving about 650mV in one direction only on the diode test setting - I very nearly didn't bother testing further at this point, given it was looking increasingly futile. Anyway, for the sake of completeness one last check across the C-E terminals and I got 295mV both 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?       -- 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.

Fox's Mercantile <jdangus@att.net>: Oct 25 10:42AM -0500 <https://www.netmeister.org/news/learn2quote.html>   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Michael Terrell <terrell.michael.a@gmail.com>: Oct 25 06:39AM -0700 > > > all.   > try a 0.1uF across the switch contacts   > m   Why?

Phil Allison <pallison49@gmail.com>: Oct 24 07:08PM -0700 Hi,   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 that are wired for 120VAC, 60Hz power.   One blew up soon as the owner plugged it in.   The second one, a Fender valve combo amp, has an auto-transformer step down that travels with it. Nevertheless, it is still vulnerable to the same accident as the first since anyone can plug 240V power into the back anytime.   On its second visit to me in a month, the 3A fuse in the back was splattered.   So, took the IEC to USA plug lead a cut off the IEC end.   Then I fitted a right angle IEC plug to the same lead.   The inlet on the amp had to be inverted so the plug would point the cable downwards when fitted. A bit of metal work had to be trimmed away.   Result: a neat installation that cannot be tampered with easily since the flush fitting plug is trapped by the removable back cover of the amp's cabinet.       ..... Phil

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.

Phil Allison <pallison49@gmail.com>: Oct 24 11:50PM -0700 Andy Burns wrote:   -------------------- > 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.   ** You have misread my post.   I live in a 240V country = Australia.   The 120V gear arrives here by air or sea from dealers in the USA.   They come packed with USA 3pin to IEC 3 pin lead which cannot be used without a step-down tranny.   But that inviting IEC inlet is still a sittun thare.   Whose barking mad idea was it for the US to adopt a 240VAC Euro supply connector ???     .... Phil

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>

Phil Allison <pallison49@gmail.com>: Oct 25 12:37AM -0700 Andy Burns is an IDIOT wrote:   ----------------------------   > 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,     ** Shame how they were designed and first standardised there for 240V power.     > most of the planet manages to produce equipment that's 120V/240V agnostic.     ** What planet is that exactly ??   Plant Burns where every fool believes his own bullshit ??   Piss off nutcase.       ..... Phil       <https://en.wikipedia.org/wiki/International_Electrotechnical_Commission#/media/File:IEC_membership.png>

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

Phil Allison <pallison49@gmail.com>: Oct 25 01:51AM -0700 Andy Burns TROLLING ASSHOLE wrote:   ------------------------------- :   > > Piss off nutcase.   > I suggest upping your medication ...   ** I suggest you consume a whole box of rat bait.   Die a horrible death.       ..... Phil

Fox's Mercantile <jdangus@att.net>: Oct 25 06:56AM -0500 On 10/25/19 1:50 AM, Phil Allison wrote:   > But that inviting IEC inlet is still a sittun thare.   > Whose barking mad idea was it for the US to adopt a 240VAC Euro supply connector ???   > .... Phil   The whole idea of the IEC connector was global markets. Want to sell US equipment overseas? Make it simple to switch input line voltages, and use the correct cord without having to change a hard wired cord. Apparently American guitar amp sellers haven't gotten the memo yet.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Phil Allison <pallison49@gmail.com>: Oct 25 05:42AM -0700 Fox's Mercantile wrote:   -----------------------   > > But that inviting IEC inlet is still a sittun thare.   > > Whose barking mad idea was it for the US to adopt a 240VAC Euro supply connector ???   > The whole idea of the IEC connector was global markets.     ** Bullshit.     > Want to sell US equipment overseas? Make it simple to switch > input line voltages, and use the correct cord without having > to change a hard wired cord.     ** Strange how they are fitted to so much 120V ONLY gear then ?   For a great time, maybe still, it was not legal to sell domestic appliances in the USA user switchable to a higher voltage than 120V.   For very obvious safety reasons.   Way over your totally fucked head.   YOU are one arrogant, revolting Ass.       .... Phil

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.}---

Ralph Mowery <rmowery28146@earthlink.net>: Oct 24 07:48PM -0400 In article <qota2l$h0t$1@reader2.panix.com>, vjp2.at@at.BioStrategist.dot.dot.com says... > 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.   Most of the LED bulbs ( the 40, 60,100 watt replacements) are made up of a ring of LEDs that are about 1/8 to 1/4 of an inch square. The long 4 foot tubes are made up of a string of similar small LEDs. They usually have capacitors in them that hold a charge that takes a second or two to fully discharge.   What gets me is the LED tubes that I have. Some come on as soon as the switch is turned on and some take about 2 seconds to come on.

tabbypurr@gmail.com: Oct 25 01:45AM -0700 > 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.   LED & hlogen look very different, there's no mistaking them.     NT

Phil Allison <pallison49@gmail.com>: Oct 25 01:53AM -0700 vjp...@at.biostrategist.dot.dot.com wrote:   ---------------------------------------------   > I am deathly afraid of halogen because of fires and I > keep wondering if I got halogen instead.   ** Well, that is a new phobia to me.   Wot is the fire issue with halogen light bulbs?   None the industry knows of.     ..... Phil

Stu jaxon <stankowalski02@gmail.com>: Oct 24 02:04PM -0700 Hi Group, can someone help please?, This Sceptre 55 inch tv can to me with no backlights, I repaired those and they are working fine. Now i have a faint blue screen, no pic and no signal, I have no remote, the only button that works is the on/off. I replaced the main board three times, along with the tcon board, no results. there is proper voltage to the main board. I tested the fuse on the tcon bd and there is 12v. no voltage on pins to the ribbon cables to the panel, they are all less than one volt. any help in this matter will be taken seriously, Thanks.   Stan..

John-Del <ohger1s@gmail.com>: Oct 24 02:59PM -0700 On Thursday, October 24, 2019 at 5:04:55 PM UTC-4, Stu jaxon wrote: > Hi Group, can someone help please?, This Sceptre 55 inch tv can to me with no backlights, I repaired those and they are working fine. Now i have a faint blue screen, no pic and no signal, I have no remote, the only button that works is the on/off. I replaced the main board three times, along with the tcon board, no results. there is proper voltage to the main board. I tested the fuse on the tcon bd and there is 12v. no voltage on pins to the ribbon cables to the panel, they are all less than one volt. any help in this matter will be taken seriously, Thanks.   > Stan..   Something may have gone wrong when you removed the display from the frame. It could have been a static discharge or a damaged ribbon on (one of) the address board(s).   If the tcon has two ribbons to the display, see if it runs with just one ribbon connected to the display (then try the other side).   Otherwise, you really should scope the differential signals both going into and out of the tcon to see what's going on.

Paul Drahn <pdrahn@jodeco.com>: Oct 24 02:20PM -0700 On 10/20/2019 6:29 AM, John Robertson wrote: > what their replacement policy is - assuming the inspection shows nothing > snuck in with the fan!   > John :-#)#   No need to take it apart. Just blow the dust and dirt out with compressed air.   Paul

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