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Cursitor Doom <curd@notformail.com>: Mar 16 06:16PM On Wed, 16 Mar 2016 09:42:30 -0700, DaveC wrote:   > "checked out fine..." means you tested what? Capacitance? ESR? > In-circuit? Removed?   > Details!   The ESRs were slightly high (in circuit) but not enough to cause sudden total failure. But they appear to be easily removeable so I'll take them out and check them independently. I should repeat I don't have the time right now to go down every avenue if this turns out to be more than a simple fix; I'm really just trying to establish whether the thing is salvageable at all. However, I am noting down all the suggestions made here for future reference for when I do have time.

DaveC <not@home.cow>: Mar 16 11:45AM -0700 > "checked out fine..." means you tested what? Capacitance? ESR? > In-circuit? Removed?   Visually?

Cursitor Doom <curd@notformail.com>: Mar 16 07:36PM On Wed, 16 Mar 2016 11:45:04 -0700, DaveC wrote:   >> "checked out fine..." means you tested what? Capacitance? ESR? >> In-circuit? Removed?   > Visually?   No signs of bulging or seepage.   I was just taking a closer look at the board a moment ago under a glass and spotted something that requires further investigation. Going to have to get my stereoscope out of storage for this one. Tiny clusters of what look like *very* fine gauge enamel copper wire clearly bridging across vias in various points around the board and obviously not *supposed* to be there. If they turn out to be conductive, I could be in business! Don't want to get my hopes up on this one, though. Probably just a false alarm but *definitely* requiring closer examination with something more powerful than a glass....   Turns out to get the caps out of circuit requires a 6mm ring spanner which I shall have to procure from a local emporium tomorrow when they re- open. Fortunately I already have a 13mm one for the other ends.

DaveC <not@home.cow>: Mar 16 01:00PM -0700 > Turns out to get the caps out of circuit requires a 6mm ring spanner > which I shall have to procure from a local emporium tomorrow when they re- > open. Fortunately I already have a 13mm one for the other ends.   Try 1/4". That's 6.35mm. Might work...

Cursitor Doom <curd@notformail.com>: Mar 16 08:23PM On Wed, 16 Mar 2016 13:00:19 -0700, DaveC wrote:   >> re- >> open. Fortunately I already have a 13mm one for the other ends.   > Try 1/4". That's 6.35mm. Might work...   I simply don't have anything that small (apart from sockets which are no good in this case) in either metric or imperial, I'm afraid. It won't kill me to buy one the correct size tomorrow.

Cursitor Doom <curd@notformail.com>: Mar 16 11:21PM On Tue, 15 Mar 2016 19:59:53 -0500, legg wrote:   > 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 don't know how the hell you were able to spot those markings from the poor detail in the photo. The last two details you posted show the extremely fine enamel copper wire-looking debris which crops up in other places on the board and across vias and traces. If this debris conducts, it could easily be the cause of the problem. I have to hoist my stereoscope out of storage and take a better look tomorrow. Well spotted indeed. Remarkable!   As for the other bits you found, I'll investigate them at the same time when my stereoscope is set up.

Jon Elson <elson@pico-systems.com>: Mar 16 08:51PM -0500 Cursitor Doom wrote:   > look like *very* fine gauge enamel copper wire clearly bridging across > vias in various points around the board and obviously not *supposed* to > be there. Woo Hoo! Sounds like tin whiskers! The conformal coat is "SUPPOSED" to suppress the whisker growth, but there are quite a few reports that the whiskers just poke through the coating, they ARE real sharp.   Jon

legg <legg@nospam.magma.ca>: Mar 16 10:50PM -0500 On Wed, 16 Mar 2016 23:21:41 -0000 (UTC), Cursitor Doom >indeed. Remarkable!   >As for the other bits you found, I'll investigate them at the same time >when my stereoscope is set up.   Looked to me more like dye concentrating as the curing epoxy puckered.   Did you ever reset this thing, while it was still in the vehicle?   RL

Cursitor Doom <curd@notformail.com>: Mar 17 10:08AM On Wed, 16 Mar 2016 22:50:06 -0500, legg wrote:   > Looked to me more like dye concentrating as the curing epoxy puckered.   So not likely to cause a fault then?   > Did you ever reset this thing, while it was still in the vehicle?   No. I think if the fix were that simple the service specialists who swapped the unit over wouldn't have gone to the trouble of sourcing a replacement. They charged me next to nothing for the job so I trust them.

Cursitor Doom <curd@notformail.com>: Mar 17 10:16AM On Wed, 16 Mar 2016 20:51:46 -0500, Jon Elson wrote:   > suppress the whisker growth, but there are quite a few reports that the > whiskers just poke through the coating, they ARE real sharp.   > Jon   Thank you, Jon. An interesting suggestion! But I was under the impression that:   1. TW growth happened solely inside chips and so was normally invisible.   2. tin whiskers were invariably silver in colour.   These I have here are like the old kind of enamel copper wire. Nowadays all enamel copper seems to be clear, but back in the day the enamel was a sort of deep plum shade - which is what I see here. I'll do some searches for pictures of TW and see if some match what I see on this board....

Look165 <look165@numericable.fr>: Mar 17 12:07PM +0100 I wonnder how you can determine an ESR visually !   And technically, it's not so easy to measure this parameter.     Cursitor Doom a écrit :

legg <legg@nospam.magma.ca>: Mar 17 08:04AM -0500 On Thu, 17 Mar 2016 10:08:49 -0000 (UTC), Cursitor Doom   >On Wed, 16 Mar 2016 22:50:06 -0500, legg wrote:   >> Looked to me more like dye concentrating as the curing epoxy puckered.   >So not likely to cause a fault then?   Must have been pretty strong stuff, to strip colour out of the mask, but no, not a conductive path.   >No. I think if the fix were that simple the service specialists who >swapped the unit over wouldn't have gone to the trouble of sourcing a >replacement. They charged me next to nothing for the job so I trust them.   ?? Just charged you for the ECU, that they happened to have lying around? Very obliging...   If you trusted them from past work, that's another thing entirely.   RL

MJC <gravity@mjcoon.plus.com>: Mar 17 01:01PM In article <nce05k$n7j$2@dont-email.me>, curd@notformail.com says... > all enamel copper seems to be clear, but back in the day the enamel was a > sort of deep plum shade - which is what I see here. I'll do some searches > for pictures of TW and see if some match what I see on this board....   I didn't know modern enamel had gone clear. Sounds like a recipe for confusion! Even if all enamel is now also the sort that turns into flux if you try to solder the wire...   Mike.

Cursitor Doom <curd@notformail.com>: Mar 17 03:41PM On Thu, 17 Mar 2016 08:04:41 -0500, legg wrote:   > ?? Just charged you for the ECU, that they happened to have lying > around? Very obliging...   It wasn't a stock item. They had to order it in and it took about 10 days in all. I'm normally suspicious, but not on this one.

Cursitor Doom <curd@notformail.com>: Mar 17 03:46PM On Thu, 17 Mar 2016 13:01:37 +0000, MJC wrote:   > confusion! Even if all enamel is now also the sort that turns into flux > if you try to solder the wire...   > Mike.   Sorry, no idea what you're getting at here.

DaveC <not@home.cow>: Mar 17 08:43AM -0700 > only one pinch roller is engaged at a time, depending upon which direction > the tape is traveling?   Yes > so the two flywheels turn in opposite directions?   Yes > How do they get the second flywheel to spin in the opposite direction?   look at the diagram (in the original post). The Belt goes around the 2 flywheels such that the belts are driven in opposite directions. > Maybe that has something to do with the need for a different size?   > M   Flywheels are differentdiameters AND capstan spindles (pressed into the center of the flywheels) are different diameters. The flywheel/spindle diameters are calculated such that the resulting tape speed is the same for both, only in opposite directions (one for Side A, one for Side B).   The reason for the differences, it seems, is to help avoid (or minimize) resonant frequency set up by the spindles turning in their bearings. Different diameters/speeds = lower resonance.   (op)

Cydrome Leader <presence@MUNGEpanix.com>: Mar 17 05:07AM >> 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.   You're right. I re-read and saw it's for the +/- 15 rails. Still not really sure why a fuse there would not suffice though. The parts did their job so they did work as designed.   >> doesn't really explain what the breaker >> is protecting against though.   > ** A major fault of course - one that would burn the transformer.   yup.

Phil Allison <pallison49@gmail.com>: Mar 16 10:55PM -0700 Cydrome Leader wrote:       > You're right. I re-read and saw it's for the +/- 15 rails. Still not > really sure why a fuse there would not suffice though.   ** Looks to me like the unit has no easily replaced fuses - probably a good idea both for reliability and to avoid over hazardous fusing by amateurs.     .... Phil

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 16 06:34PM "legg" wrote in message news:o72jebd0tngn1f8gd9p5dqma845lgp9tk4@4ax.com...   On Fri, 4 Mar 2016 20:07:16 -0000, "Gareth Magennis" >jack >tip becomes separated from it's body and is left embedded in the Combi.   >Not good.   Most likely due to poor quality control in plug mfr. 'Normally' you'd expect to see the broken tip connector still attached to the central conductor, which holds the whole shebang together with a single swage in the wire connection area. It's a single piece. You shouldn't be able to break this into two pieces with manual extraction forces. A 'grabby' socket terminal would distort and crumple first.   Equipment vendors will often add an advisory in their users manual to use only parts complying to the standards, or mention specific mfrs brand types. Sockets are not manufactured to deal with this type of failure.   This is a simple plug and socket.   European standard is IEC60603-11.   You might mention the brand name or source of the broken part, so that others can avoid it, rather than running down Neutrix. The latter are exhorbitantly priced, but they work.   RL         That's the problem though, these cheap jacks are unbranded shite, poorly made. I am not trying to run down Neutrik, I know how good their products are, I personally don't use any other brand.     Problem also is, these cheap jacks make Neutrik look like the sole problem since they don't get stuck elsewhere.       Gareth.

mjb@signal11.invalid (Mike): Mar 16 09:24PM >People buy nice gold coloured , gold plated , connectors on blingey >leads and pay over the odds for them. But the phono jacks are crap, the >ground connector is a solid ring, no axial cuts to them, so they jam ...   High friction level + meaty connector body + fat "oxygen free" triple- plaited silver-loaded wire.   Great combination. Requires lots of insertion force AND provides lots of angular pull once in ... leading to the phono sockets breaking free of the PCB.   Money well spent.   -- --------------------------------------+------------------------------------ Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk

legg <legg@nospam.magma.ca>: Mar 16 10:33PM -0500 On Wed, 16 Mar 2016 18:34:37 -0000, "Gareth Magennis"   >Problem also is, these cheap jacks make Neutrik look like the sole problem >since they don't get stuck elsewhere.   >Gareth.   Bite each one to test, before paying?   Better than getting bitten.   RL

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