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N_Cook <diverse@tcp.co.uk>: Feb 02 02:46PM No PbF statements anywhere but I assume it is. Reported as consistent intrusive mains hum with any settings of controls, but of course with me it is perfect. Expecting a loose cap or input socket problem, but nothing found. Before dismantling the amp, anything to check , from access side only at the moment. So far,cursory comparison, circuit looks like this one http://www.schematicsunlimited.com/o/orange/orange-rockerverb-guitar-amplifier-schematic/download/OTQ2Nw%3D%3D

dansabrservices@yahoo.com: Feb 02 07:11AM -0800 On Tuesday, February 2, 2016 at 9:46:47 AM UTC-5, N_Cook wrote: > anything to check , from access side only at the moment. > So far,cursory comparison, circuit looks like this one > http://www.schematicsunlimited.com/o/orange/orange-rockerverb-guitar-amplifier-schematic/download/OTQ2Nw%3D%3D   Sounds like a polarity problem with the AC input. Is there are polarity switch on this unit? Floating ground?

jurb6006@gmail.com: Feb 01 09:04AM -0800 There were also Sonys like that. I thought it was leakage in the neon that caused that failure.

"pfjw@aol.com" <pfjw@aol.com>: Feb 02 05:44AM -0800 On Monday, February 1, 2016 at 10:09:10 AM UTC-5, N_Cook wrote: > and flashes if its night time and next to no low light in the room, if > the ps is left switched on. Its a pip type, only a pip protrudes through > the casing if that is relevant.   This is an easy one... your vision is not linear based on lighting conditions, but very relative. A flash or low glow in a neon bulb would be entirely invisible under normal-light conditions, but in low light, your heightened sensitivity would pick it up easily. Further, Neon lamps, after they trigger, are not like many LEDs which are on/off devices. Once they trigger, voltage may drop considerably and they will still remain lit. So, if there is a capacitor in the circuit to trigger it, then when it reaches that point and 'fires' the lamp will flicker. But the carrier voltage to keep it running is not there. So it is only a flicker.   Some SS-relay operated neon ballasts from the very early days of electronic ballasts behaved the same way if wired with the 'neutral' switched, or at 277V under some conditions. Firing voltage is achieved, but operating voltage is not present. They flash. And if, as in some Euro applications, the "neutral" is above ground, this can be a real issue. The ballast design changed pretty quickly for this reason.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Feb 02 05:49AM -0800 > There were also Sonys like that. I thought it was leakage in the neon that caused that failure.   Yes, NE2 lamps age, and their internal resistance changes as a result. So, if the circuit depends on 'sensing' the operation of the neon lamp, and the operating resistance changes sufficiently, the circuit will latch.   Small pen-type one-point voltage sensors discern between AC & DC by only one side or the other glowing under DC, both under AC. Back in the day where mains DC was common (up to 2007 in NYC), that was important to know at a glance.   http://cityroom.blogs.nytimes.com/2007/11/14/off-goes-the-power-current-started-by-thomas-edison/?_r=0   Peter Wieck Melrose Park, PA

MJC <gravity@mjcoon.plus.com>: Feb 02 02:19PM In article <a01e0a11-b02e-4c29-a8f4-668cddee8b92@googlegroups.com>, pfjw@aol.com says...   > Yes, NE2 lamps age, and their internal resistance changes as a result.   BTW What does the "2" signify?   Mike.

Chuck <chuck@mydeja.net>: Feb 02 08:33AM -0600 On Tue, 2 Feb 2016 14:19:50 -0000, MJC <gravity@mjcoon.plus.com> wrote:     >> Yes, NE2 lamps age, and their internal resistance changes as a result.   >BTW What does the "2" signify?   >Mike. It is a type of bulb number.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chuck <chuck@mydeja.net>: Feb 02 08:41AM -0600 >Without a memory, either mechanical or electronic, this should have >been reset on recycling of power.   >RL     It was channel independent, never intermittent and not hot or cold dependent and the sets never returned for the same problem. By the way Jur006 had the correct explanation. I had forgotten what it was but his answer jarred my memory.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chuck <chuck@mydeja.net>: Feb 02 08:43AM -0600 >There were also Sonys like that. I thought it was leakage in the neon that caused that failure.   You are right. I had forgotten that was what caused the problem. Thank you for jarring my memory.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Miguel Giménez" <me@privacy.net>: Feb 02 12:10PM +0100 Hello   I'm trying to repair a dead LG 32LS570S LCD screen. The backlight work OK, all the power supply voltages are nominal and the unit turns on and off via the remote or the keypad, but there is no image. The service manual says "change the main board", but first I want to ask here if this is a known fault.   Thank you   -- Saludos Miguel Giménez

John-Del <ohger1s@aol.com>: Feb 02 06:35AM -0800 On Tuesday, February 2, 2016 at 6:11:03 AM UTC-5, Miguel Giménez wrote:   > -- > Saludos > Miguel Giménez   There are four causes of your problem: bad main, bad LVDS cable, bad tcon, bad display (display and tcon are often combined in cheap TVs). You can either start buying parts and throwing them at the TV or you can scope for differential signals and check the dc buck converters at the main and tcon for proper voltages.

frank <frank@invalid.net>: Feb 02 12:00PM Hi all,   I'm repairing an old Commodore 1702 CRT monitor. The PTC driving the degauss coil desoldered itself from the PCB, probably it was too hot (missing solder from the "common" pin of the two PTCs). This PTC (dual type, one across the 240V line, one in series with the coil) is marked CE 40595-1 / 4 0 0 3 / TDK (on three different lines). The degauss coils measures 12 ohms at DC. I haven't found any reference about this PTC so I can't decide if it's good or not. It measures 6 ohms in the coil side and 126 ohms in the AC side when cold. The only service manual I've found for this monitor lists a JVC part number for the PTC that gives no results on google. However the PTC I've found on the monitor PCB look the original one since the soldering on the pins (the ones that didn't desolder themselves) looked original. I'm tempted to put a 18 ohms (on the coil side) standard TV PTC on it (the C180N kind), but I seek suggestions and hints. Thanks in advance   Frank IZ8DWF

N_Cook <diverse@tcp.co.uk>: Feb 02 12:34PM On 02/02/2016 12:00, frank wrote: > C180N kind), but I seek suggestions and hints. > Thanks in advance   > Frank IZ8DWF   Any room for a/few suitably rated polyswitch/s as a backup in case it doesn't drop out?

frank <frank@invalid.net>: Feb 02 01:01PM > Any room for a/few suitably rated polyswitch/s as a backup in case it > doesn't drop out?   hm, I *could* find room for a couple of them, that would prevent solder melting in case of failure, but still I'd like to replace the original PTC if it's faulty.   Thanks Frank IZ8DWF

firstimpressionbob@gmail.com: Feb 01 12:46PM -0800 On Saturday, 17 May 2008 16:34:37 UTC+1, Graz wrote: > When switched on, shows "1" (out of range) on all ranges instead of > "000". Any suggestions as to where to start troubleshooting? > All suggestions welcome - even facetious ones!   Hello Graz Mine has the same fault, Its been a fantastic tool untill it went wrong, Did you get any answers please. Robert

firstimpressionbob@gmail.com: Feb 01 12:46PM -0800 On Saturday, 17 May 2008 16:34:37 UTC+1, Graz wrote: > When switched on, shows "1" (out of range) on all ranges instead of > "000". Any suggestions as to where to start troubleshooting? > All suggestions welcome - even facetious ones!   Hello Graz Mine has the same fault, Its been a fantastic tool untill it went wrong, Did you get any answers please. Robert

Tim R <timothy42b@aol.com>: Feb 01 09:34AM -0800 > > >This past week I was coming from the other direction and clearly saw the street light flash twice, very brightly.   > red light cam?   I'll have to drive past there on the other road. My impression was street light, not near the traffic signal.   It's a part of town not conducive to hanging around watching for it to recur.

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