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Cursitor Doom <curd@notformail.com>: Mar 14 11:02PM Hi guys,   I have an EMU from a Land Rover which just suddenly failed one day without warning as I was driving down the road. I was wondering if there's any possibility of fixing it, given that schematics are AFAIK unavailable due to commercial confidentiality. Of course there are some basic checks that can be done without a diagram, but take a look at this thing and tell me what I could try doing with it. I've carefully inspected it close up but can find *nothing* at all visibly wrong with it:   http://tinyurl.com/hvk5eac   BTW, the whole board has been thickly sprayed with clear varnish which accounts for all the bright dots which appear on some of the parts - they're not indicative of any failure.   Any suggestions?

Clifford Heath <no.spam@please.net>: Mar 15 06:06AM +1100 On 15/03/16 10:02, 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?   "My car is broken. Can you tell me how I can fix it?"

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Mar 15 12:24AM +0100 On 15.03.16 0:02, 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?   A:try to get a replacement from a car wreckers shop. B:Or get a magnifier glass and start searching for damage/discoloration. And check big caps and big transistors. If no success, try solution A. Or let repair shop handle it.

Cursitor Doom <curd@notformail.com>: Mar 14 11:39PM On Tue, 15 Mar 2016 00:24:02 +0100, Sjouke Burry wrote:   > And check big caps and big transistors. > If no success, try solution A. > Or let repair shop handle it.   It's up and running again with an exchange unit, but it ran smoother, quieter and started up quicker with the old unit that failed, so I'd like to get the old one working again if at all possible.

Clifford Heath <no.spam@please.net>: Mar 15 06:42AM +1100 On 15/03/16 10:39, Cursitor Doom wrote:   > It's up and running again with an exchange unit, but it ran smoother, > quieter and started up quicker with the old unit that failed, so I'd like > to get the old one working again if at all possible.   It can take some time for an ECU to "learn" your engine. You'll probably find it runs just as well as the old one after a tank or two of gas.

M Philbrook <jamie_ka1lpa@charter.net>: Mar 14 07:52PM -0500 In article <56e744db$0$41576$b1db1813$145976f0@news.astraweb.com>, no.spam@please.net says... > > they're not indicative of any failure.   > > Any suggestions?   > "My car is broken. Can you tell me how I can fix it?"   I have fixed a couple of ECM's and in both cases the Xstal failed due to mechanical vibration. Power it up using basic shop electrical prints to the unit and find that the Xstal not operating.   Another one I did was intermitting in some function and popping up codes randomly. I replaced a couple of caps, fixed.. The coating is tricky to get off without damage.   Jamie

M Philbrook <jamie_ka1lpa@charter.net>: Mar 14 07:58PM -0500 In article <nc7i2r$ui0$2@dont-email.me>, curd@notformail.com says...   > It's up and running again with an exchange unit, but it ran smoother, > quieter and started up quicker with the old unit that failed, so I'd like > to get the old one working again if at all possible.   That will fix itself.   The same is true if you disconnected the battery for a while with the other one.

Cydrome Leader <presence@MUNGEpanix.com>: Mar 14 07:28PM > If you force them out, the tip of the jack will just not get past the > connector, but instead will just take it with it and destroy it, or the jack > tip becomes separated from it's body and is left embedded in the Combi.   It's not surprising combination connectors sort of suck in practice. That jack looks about on par with a chinese travel plug adapter.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 14 11:50PM "Cydrome Leader" wrote in message news:nc73cv$hcb$1@reader1.panix.com...   > connector, but instead will just take it with it and destroy it, or the > jack > tip becomes separated from it's body and is left embedded in the Combi.   It's not surprising combination connectors sort of suck in practice. That jack looks about on par with a chinese travel plug adapter.         I think you missed the point.     The Neutrik Combi works fine usually.   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.       Gareth.

Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Mar 14 12:56PM -0400 Over the years I've had to replace maybe a half dozen thermal fuses which appear to have failed without ever being heated beyond their rated temperatures.   Most recently a small electric space heater used in our office under my desk stopped working because its thermal fuse had opened. The fuse was a MICROTEMP G4A0 121 degree C unit, and I'm pretty sure that nothing had blocked air passage through the heater and caused its internal temperature to rise enough to open the thermal fuss.   Jeff     -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

John Robertson <spam@flippers.com>: Mar 14 10:20AM -0700 On 03/14/2016 9:56 AM, Jeff Wisnia wrote: > blocked air passage through the heater and caused its internal > temperature to rise enough to open the thermal fuss.   > Jeff   My expectation is yes, they do fail from age/power cycles. Most likely failure point is the wire to passive element junction...why not take it apart and see?   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

N_Cook <diverse@tcp.co.uk>: Mar 14 06:21PM On 14/03/2016 16:56, Jeff Wisnia wrote: > blocked air passage through the heater and caused its internal > temperature to rise enough to open the thermal fuss.   > Jeff   They also have a current limit , but I do believe than can fail by deterioration or something

Cydrome Leader <presence@MUNGEpanix.com>: Mar 14 06:29PM > MICROTEMP G4A0 121 degree C unit, and I'm pretty sure that nothing had > blocked air passage through the heater and caused its internal > temperature to rise enough to open the thermal fuss.   They seem to have poor aging characteristics. I've seen dead thermal fuses in completely unused spares heater assemblies sitting on shelves for years. Everything was x-rayed so new ones could be custom made. Told them to leave out the thermal fuses on the new ones.

"pfjw@aol.com" <pfjw@aol.com>: Mar 14 11:43AM -0700 On Monday, March 14, 2016 at 12:56:59 PM UTC-4, Jeff Wisnia wrote: > blocked air passage through the heater and caused its internal > temperature to rise enough to open the thermal fuss.   > Jeff   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.   Peter Wieck Melrose Park, PA

Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Mar 14 02:44PM -0400 Cydrome Leader wrote: > in completely unused spares heater assemblies sitting on shelves for > years. Everything was x-rayed so new ones could be custom made. Told them > to leave out the thermal fuses on the new ones.   Thanks folks, I think my guess about aging effects was probably correct.   The only PIA for me is now that I'm retired and no longer working for a company which does business with component suppliers I have to find out where to buy things like those thermal fuses myself. (When Mozart was my age he'd been dead for 45 years.)   Radio Shack used to carry thermal fuses and I could have one sent to a local store two blocks away from our home for pickup by me at no extra charge, but they're kaput now so I had to go online and buy one for 75 cents and pay a minimum $5.50 for S&H.   Oh well, I would have used up that many dollars in driving costs running around trying to find one locally, and it's still cheaper than buying a new heater.   Yes I could have just shorted it out and been extra careful using the heater, but my luck is so bad that if someone gave me a cemetery people would stop dying. I might burn down the whole building with that heater and have some smart investigator tie it to my replacing the thermal fuse with a piece of wire.   Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Mar 14 03:06PM -0400 > 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.   > Peter Wieck > Melrose Park, PA   That may be what's going on inside the 2Amp 3AG fast blow fuses I installed in the four metal bodied table lamps I'd added "touch dimmers" to.   When the 150 watt bulbs I use in those lamps burned out the "thermal arc" would often send the touch dimmers to the graveyard, so I added fuse holders and fuses to the lamps. Those fuses protect the touch dimmers, even though I have to replace a 15 cent fuse almost every time a bulb burns out.   It's still worth having touch dimmers in the lamps because SWMBO and I don't have to stick our arms up under the lamp shade and fumble around for the rotary switch on the socket.   Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

Look165 <look165@numericable.fr>: Mar 14 09:38PM +0100 My opinion is electrical peak ( = overvoltage ) !     Jeff Wisnia a écrit :

Cydrome Leader <presence@MUNGEpanix.com>: Mar 14 09:22PM > local store two blocks away from our home for pickup by me at no extra > charge, but they're kaput now so I had to go online and buy one for 75 > cents and pay a minimum $5.50 for S&H.   Ha! RS was my thermal fuse and sketchy crimp terminal supplier of choice too.

Jon Elson <jmelson@wustl.edu>: Mar 14 05:24PM -0500 Jeff Wisnia wrote:   > blocked air passage through the heater and caused its internal > temperature to rise enough to open the thermal fuss.   > Jeff   After having the thermal fuse in our dishwasher fail several times, and then an aftermarket part fail on the first time it was used, I bought some from Digi-Key. Hmmmph, should have known better, DON'T solder it in without a heat sink! The (2nd) new part seems to be working fine. Instead of $15 each for a nice piece in a plastic housing with 1/4" quick-connect terminals, I can get a bare sensor/fuse for $1.50 from Digi-Key.   Jon

Look165 <look165@numericable.fr>: Mar 14 09:45PM +0100 Bios virus   janetnkansah1@gmail.com a écrit :

Look165 <look165@numericable.fr>: Mar 14 09:42PM +0100 Farnell !     DaveC a écrit :

DaveC <not@home.cow>: Mar 14 11:29AM -0700 On 14 Mar 2016, N_Cook wrote > then be compatible to 2 available bearing diameters and hence spindle > diameters. > That is the reason i'd go for   I (op) have accepted the theory that difference is to avoid additive resonance of the capstan shafts in bronze(?)--not ball--bearings. Difference flywheel sizes plus different capstan shaftssizes (2mm and 2.1mm) results in same tape speed (in opposite directions--this is an auto-reverse mechanism) and different resonances.

"pfjw@aol.com" <pfjw@aol.com>: Mar 14 11:41AM -0700 On Monday, March 14, 2016 at 12:28:26 PM UTC-4, legg wrote:     > Supposition is that the difference in flywheel dia is related to belt > thickness, as one flywheel is inside, and other is outside the drive > belt loop.   Um... A flywheel is a momentum device attached to a system to provide smoothing. Many (very much most) DC motors are pulse driven. The flywheel removes these pulses. Tape speed is determined by the capstan motor pulley diameter. FULL STOP.   Peter Wieck Melrose Park, PA

legg <legg@nospam.magma.ca>: Mar 14 03:56PM -0500 On Mon, 14 Mar 2016 11:41:28 -0700 (PDT), "pfjw@aol.com" >> thickness, as one flywheel is inside, and other is outside the drive >> belt loop.   >Um... A flywheel is a momentum device attached to a system to provide smoothing. Many (very much most) DC motors are pulse driven. The flywheel removes these pulses. Tape speed is determined by the capstan motor pulley diameter. FULL STOP.   In these machines a single motor with a pulley on its shaft, drives the outer rims of the two differently sized flywheels, through a single belt.   I've measured the spindles at the pinch rollers and they are a different diameter, as was suggested by DaveC, so belt thickness isn't responsible for compensation of the flywheel sizes - the spindles are scaled with the flywheel diameter.   Never occurred to me to wonder about this, before, or to check it out. Happy just to keep them going.   RL

Cydrome Leader <presence@MUNGEpanix.com>: Mar 14 07:00PM > (One side has melted both these wire fuses, as the caps are bad)   > Why would a manufacturer do this? I'd be inclined to put back wire ended > fuses.   Fusible links handle surge currents better than fuses.   My question is why is on the output of the transformer. Is the input fused at all?

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