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legg <legg@nospam.magma.ca>: Mar 15 02:25PM -0500 On Tue, 15 Mar 2016 14:04:46 -0000 (UTC), Cursitor Doom >>>cheap!   >> The issue is with the new part, not the old one.   >Wrong! The question *solely* concerns the *old* unit that failed.   The issue is your dissatisfaction with the repaired automobile.   You're not in a position to resurrect the old ECU.   RL

DaveC <not@home.cow>: Mar 15 11:49AM -0700 On 15 Mar 2016, Cursitor Doom wrote   > Wrong! The question *solely* concerns the *old* unit that failed.   Welcome to USENET. There is no "on-topic"!   Under conformal coating it is difficult to examine anything.   Check any large transistors.   I'd also look for broken solder joints on the large devices (caps, transformer, choke, I/O connectors). Also look closely at the cap "north" of the big choke. Has it leaked and damaged a trace?   Also check ESR of all the electro caps.   And as was mentioned earlier, be sure the xtal is working. A success story:   https://www.youtube.com/watch?v=uLIHxqqrY_M   Good luck!

DaveC <not@home.cow>: Mar 15 12:09PM -0700 If all else looks good, a winding in that transformer might be open. Remove and "ring" it.

Cursitor Doom <curd@notformail.com>: Mar 15 08:01PM On Tue, 15 Mar 2016 14:25:41 -0500, legg wrote:     >>Wrong! The question *solely* concerns the *old* unit that failed.   > The issue is your dissatisfaction with the repaired automobile.   > You're not in a position to resurrect the old ECU.   The new ECU in all probability just requires a software tweak. My question was about the OLD one (at the risk of repeating myself).

Jon Elson <jmelson@wustl.edu>: Mar 15 04:53PM -0500 Cursitor Doom wrote:   > accounts for all the bright dots which appear on some of the parts - > they're not indicative of any failure.   > Any suggestions? Well, are there any symptoms that can be figured out? Do dash indicators do something like what they used to do? If it appeas totally dead, there's a possibility that a voltage regulator or other power switching circuit has failed. Looks like it has a switching power supply, that will make things a little harder. Yeah, the conformal coating is really necessary in automotive gear, but makes rework tough.   Also, check all connectors and other large parts soldered to the board, breaks in the solder joints are supposed to be a very common cause of failure.   Jon

legg <legg@nospam.magma.ca>: Mar 15 07:59PM -0500 On Tue, 15 Mar 2016 20:01:54 -0000 (UTC), Cursitor Doom   >> You're not in a position to resurrect the old ECU.   >The new ECU in all probability just requires a software tweak. My >question was about the OLD one (at the risk of repeating myself).   There's not much you can tell from a photograph of limited resolution. Looking at what you've offered, you might re-examine locally:   http://www.magma.ca/~legg/TVS/EMU_captive_detritus.jpg http://www.magma.ca/~legg/TVS/EMU_green_reflection.jpg http://www.magma.ca/~legg/TVS/EMU_red_reflection.jpg http://www.magma.ca/~legg/TVS/EMU_soluble_contaminant.jpg http://www.magma.ca/~legg/TVS/EMU_soluble_contaminant_2.jpg   I expect these are mostly reflections in the protective epoxy, or flow/tension marks formed in its application, but could be signs of contamination or damage.   Even checking point to point contact is a trial with this stuff.   Vibration produces intermittent faults on assemblies (where the parts don't actually shear off completely) The most suspect parts are those with mechanical attributes - the crystal as previously suggested, the connectors and bulky components. Reflowing the SJ of the latter might be informative - any uncharacteristic loosness in the soldered material of the melted joint is a giveaway.   As previous - an intermittent fault is unlikely to result in repeated DOA symptoms, but it can be recorded for posterity in the firmware, with DOA symptoms, or break small-signal paths with the same effect.   Did you try a reset on the 'dead' unit, before replacing it?   The fact that its replacement didn't involve the surrender of the defect unit (for a discount in pricing) is a signal from the mfr regarding their view on the viability of repair. They are in the most sensible position to do so, after-warranty.   RL

DaveC <not@home.cow>: Mar 15 05:21PM -0700 > http://tinyurl.com/hvk5eac   Any chance of posting a super-high resolution image?

Cursitor Doom <curd@notformail.com>: Mar 16 12:56AM On Tue, 15 Mar 2016 17:21:08 -0700, DaveC wrote:   >> http://tinyurl.com/hvk5eac   > Any chance of posting a super-high resolution image?   If I can figure out how to get the back off and photograph both sides, I'll do it. The blurring issue I am having is with the autofocus which is being hijacked by the two big electrolytics. I'll have to read the camera's FM and find out how to switch it to manual. These damn things are so complicated nowadays. :(

Cursitor Doom <curd@notformail.com>: Mar 16 01:00AM On Tue, 15 Mar 2016 19:59:53 -0500, legg wrote:   > their view on the viability of repair. They are in the most sensible > position to do so, after-warranty.   > RL   Many thanks for that lot above (and the other tips & suggestions others have come up with). I don't think I will have sufficient time at this stage to see this through to the end if it turns out to be tricky; I can't face the prospect of this becoming another saga like the Philips scope turned out to be. :( I'll try to get the back off tomorrow...

Look165 <look165@numericable.fr>: Mar 16 11:30AM +0100 I would say the 2 electrolytic caps.   Cursitor Doom a écrit :

Cydrome Leader <presence@MUNGEpanix.com>: Mar 15 10:05PM > Cheap jack plugs don't usually get stuck in any sort of jack socket.   > Except there are increasing numbers now of cheap jacks that ONLY get stuck > in a Neutrik Combi socket.   This is my point. Do-all devics are compromises and clearly this product sort of sucks, or hasn't been tested at all. Either way it still sucks, apparently.   I use some neutrik connectors and for single purpose use they're very well made so I'm a bit surprised by this problem.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 15 10:39PM "Cydrome Leader" wrote in message news:nca0v3$evd$2@reader1.panix.com...     > Cheap jack plugs don't usually get stuck in any sort of jack socket.   > Except there are increasing numbers now of cheap jacks that ONLY get stuck > in a Neutrik Combi socket.   This is my point. Do-all devics are compromises and clearly this product sort of sucks, or hasn't been tested at all. Either way it still sucks, apparently.   I use some neutrik connectors and for single purpose use they're very well made so I'm a bit surprised by this problem.         It is not at all clear whether the problem lies with the Neutrik Combi, or the possibly badly designed/made cheap jack plug.   Probably it is a combination of both, being, as I currently believe, there is no standard for jack plug/socket dimensions or tip profiles.       Gareth.

N_Cook <diverse@tcp.co.uk>: Mar 16 09:09AM On 15/03/2016 22:39, Gareth Magennis wrote:   Maybe there is a type of jack that is marketed as less likely to pull out of sockets, when gyrating about on stage or something. I'd have thought the H&S argument was to have them less likely to pull over a speaker stack, but who knows.

Phil Allison <pallison49@gmail.com>: Mar 15 06:51PM -0700 > so the two flywheels turn in opposite directions?   > How do they get the second flywheel to spin in the opposite direction?   ** Look at the diagram - the belt goes most of the way around the larger flywheel ( 153 ) but only a small part of the way around the smaller one ( 152).   IOW it fits where the "151" is shown, where the belt is curved the opposite way.   .... Phil

Cydrome Leader <presence@MUNGEpanix.com>: Mar 15 09:58PM >> My question is why is on the output of the transformer. Is the input >> fused at all?   > ** The two on/off switch incorporate circuit breakers, but the trannys are very large and the low voltage windings need protecting against an overload or short that would not trip the breakers.   I've been thinking about this and can only conclude the fusible links are to protect against further damage from someobdy recycling the input breaker on a permanent fault. It doesn't really explain what the breaker is protecting against though. You could continue to flip the breaker/switch if the primary winding have a fault or short of some type. Is this device graceful enough to just trip the breaker instead of burning up in the case of an overload?   It's just a power amp so it's not like it needs to continue to run a cooling fan or something like that in case of other failures in the system.   Strange.

Phil Allison <pallison49@gmail.com>: Mar 15 06:45PM -0700 Cydrome Leader wrote:     > I've been thinking about this and can only conclude the fusible links are > to protect against further damage from someobdy recycling the input > breaker on a permanent fault.   ** No, the breaker/switch would never react to a fault in the low voltage supply.   > doesn't really explain what the breaker > is protecting against though.   ** A major fault of course - one that would burn the transformer.       .... Phil

captainvideo462009@gmail.com: Mar 15 01:59PM -0700 This is my own receiver. For the past couple of months I've started to notice that the time it was taking for the protection relay to activate was lengthening from around three seconds to a bit longer. Then recently the time has lengthened again only this time it seems exponentially. Yesterday after switching on the receiver I counted 82 seconds before the relay tripped and I got sound out. The sound was fine when I did.   I need to pull this out of the entertainment center to check it over so it will be a few days before I actually get to this but I wanted to run this by the group first for ideas. I'm thinking perhaps dried up cap or changed resistor somewhere but that's just a guess. I know that at least part of what this circuit does is look for DC on the output but I don't really understand exactly how that works and what that circuit is or how it's looking at that so if someone could please explain it to me I would be very grateful. Thanks. Lenny.

Chuck <chuck@mydeja.net>: Mar 15 04:08PM -0500 On Tue, 15 Mar 2016 13:59:05 -0700 (PDT), captainvideo462009@gmail.com wrote:   >This is my own receiver. For the past couple of months I've started to notice that the time it was taking for the protection relay to activate was lengthening from around three seconds to a bit longer. Then recently the time has lengthened again only this time it seems exponentially. Yesterday after switching on the receiver I counted 82 seconds before the relay tripped and I got sound out. The sound was fine when I did.   >I need to pull this out of the entertainment center to check it over so it will be a few days before I actually get to this but I wanted to run this by the group first for ideas. I'm thinking perhaps dried up cap or changed resistor somewhere but that's just a guess. I know that at least part of what this circuit does is look for DC on the output but I don't really understand exactly how that works and what that circuit is or how it's looking at that so if someone could please explain it to me I would be very grateful. Thanks. Lenny.   Lenny,   It is probably that C06 33uf 50 volts has dried up. Hope this helps. Chuck   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

captainvideo462009@gmail.com: Mar 15 03:47PM -0700 > This is my own receiver. For the past couple of months I've started to notice that the time it was taking for the protection relay to activate was lengthening from around three seconds to a bit longer. Then recently the time has lengthened again only this time it seems exponentially. Yesterday after switching on the receiver I counted 82 seconds before the relay tripped and I got sound out. The sound was fine when I did.   > I need to pull this out of the entertainment center to check it over so it will be a few days before I actually get to this but I wanted to run this by the group first for ideas. I'm thinking perhaps dried up cap or changed resistor somewhere but that's just a guess. I know that at least part of what this circuit does is look for DC on the output but I don't really understand exactly how that works and what that circuit is or how it's looking at that so if someone could please explain it to me I would be very grateful. Thanks. Lenny.   Thanks Chuck. I'll look for that. Lenny

John-Del <ohger1s@aol.com>: Mar 15 11:13AM -0700 On Tuesday, March 15, 2016 at 12:29:33 PM UTC-4, Jeff Wisnia wrote: > Jeffry Wisnia > (W1BSV + Brass Rat '57 EE) > The speed of light is 1.8*10^12 furlongs per fortnight.   Make sure any plug in types have a clean and tight contact, or there'll be heat generator at the plug.

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 15 08:16PM "N_Cook" <diverse@tcp.co.uk> wrote in message news:nc6v8q$ru2$1@dont-email.me...   >> Jeff   > They also have a current limit , but I do believe than can fail by > deterioration or something   All fuses die eventually, but in most cases they outlive the equipment.   Once or twice I've even seen corrosion kill a fuse, but most thermal types are in sealed encapsulation. That would be an unlikely failure mode.

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 15 08:21PM <pfjw@aol.com> wrote in message news:f122697d-8ae2-41b4-ac4e-98102ca92234@googlegroups.com...   > They most certainly do die of old age. As do regular current-limited > fuses. If ever one wants some very dry amusement, bring a glass fuse close > to its current limit and watch the filament dance inside the glass.   Thermal fuses are often installed with crimp connections to avoid high failure rates during soldering.   Occasionally, a bad crimp makes a resistive join that heats up and pushes it past the trip point.

Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Mar 15 04:56PM -0400 John-Del wrote: >> (W1BSV + Brass Rat '57 EE) >> The speed of light is 1.8*10^12 furlongs per fortnight.   > Make sure any plug in types have a clean and tight contact, or there'll be heat generator at the plug.   Not a plug in type. This thermal fuse just has its leads soldered to lugs on the heater's thermostat and its heating element.   Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

Jon Elson <jmelson@wustl.edu>: Mar 15 04:59PM -0500 John-Del wrote:       > Make sure any plug in types have a clean and tight contact, or there'll be > heat generator at the plug. Yes, the kit that came with the aftermarket replacement had all this, and I replaced it, but it still blew the thermal fuse the first time we used it.   The Digi-Key replacement has held for several months, now.   Jon

captainvideo462009@gmail.com: Mar 15 02:05PM -0700 > Don't be afraid to take heroic measures if the alternative is landfill.   > Peter Wieck > Melrose Park, PA   Fish fingers must be very small. Do you eat them by the gross or the ounce? Lenny

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