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John Robertson <spam@flippers.com>: Aug 26 07:46AM -0700 I am replacing an old TRIAC that is used for a solenoid driver driven by a photo-flash (I have dozens of these in my classic rifle gallery) and I can't find anything on line about this particular device.   I know it is 400V, 3A, and is in a TO-11 like metal can however what I can't find is the Gate current. This is a sensitive gate TRIAC and I suspect it is either a 3MA or a 10MA device, but would like a copy of the original TECCOR specs to be sure that the replacement I am using is close enough to the original for long term reliability. This is being controlled by a device called a Vactrol - VTL2C3, and I have several dozen of these controllers that eventually need upgrading.   So, if anyone has a TECCOR Electronics Inc. manual lying around from the early 70s and can scan me the page(s) on the Q4003M3 that would be great. I have found sheets online for other flavours of the Q4003 series, but just not the Mx version.   Thanks!   John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

MOP CAP <email@domain.com>: Aug 26 07:19AM -0700 I have an old one that only prints out a totally black page with just a shadow of the intended image. ??? Is it the corotron and is it worth reparing? What is the corotron? Thanks, CP

jeff.panasuk@cfl.rr.com: Aug 26 06:11AM -0700 > Back in February or March of 2010 the TV began changing from any channel to channel 2 intermittently. Sometimes very frequent. Other times more intermittent but it would not go more than a few hours without the problem popping up. Replaced IC0102 (MN14834HH) Main IC for the Channel Selection Ckt but no help. Remote control IR circuit not the problem as I disabled it. Over time have replaced some bad unrelated hw (burnt resistor, Caps). Have schematics and service manual but can't isolate the problem. Nice picture and everything else works fine. Unit in storage but every 4 months or so, when I see it and think about it, I fire it up. Hate to trash this old tv. Kind of part of the family now. Has anyone ever heard of this before?   8/26/2017 One final note. It's been over 6 weeks now and the tv has worked fine since cleaning the 3-way switch. I guess it's fixed. Thanks for all your help guys.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Aug 25 07:09PM +0100 What's the best I can do?   All the partition managers tried so far, offer a single partition just under 750Gb and no remaining unpartitioned space.   A 2Tb drive works just fine - I'd even settle for that from the 3Tb one..........   Thanks for any help.

dplatt@coop.radagast.org (Dave Platt): Aug 25 01:08PM -0700 >750Gb and no remaining unpartitioned space.   >A 2Tb drive works just fine - I'd even settle for that from the 3Tb >one..........   I suspect that what you're running into is the 2.2-terabyte limit in the standard PC Master Boot Record. This would correspond to 32 bits worth of sectors (4 hexabillion) at 512 bytes each.   Probably, when your partition table is being built, the software you're using is trying to read the hard drive size via the PC BIOS, and the sector count is wrapping around past 4 billion. The program ends up with (3 terabytes - 2.2 terabytes) worth of sectors, and so you only get 750 GB.   I'm not an expert in the PC BIOS, but I suspect that the "read drive sector count" call returns a 32-bit result, and the BIOS isn't smart enough to clip (rather than wrap) at 2.2 terabytes. If that's the case, no matter what program you use, you'll hit the same behavior.   There's probably a fix, although it won't be trivial. What you would need to do is let the software partition the drive. If you want more than one partition, delete the single 750-gig existing one and create the smaller ones you want at first, and then create a final partition which uses up the remainder of the 750 GB space.   Then go in with a sector-level disk editing program, and edit the partition table by hand. Take a look at   https://en.wikipedia.org/wiki/Master_boot_record   You'd want to edit the "number of sectors in partition" value at offset 12 (0x0C) for the last (or only) partition and set it to "0xFFFFFFFF" (or slightly less than that) and store this entry. This would expand that partition to 2.2 terabytes.   Save the MBR, reboot, and I think you'd find that you have more space available.   HOWEVER: depending on how your PC accesses the drive, you could find that Bad Things happen when it tries to write beyond the 2.2-terabyte boundary - reads and writes might wrap around to the beginning of the disk. For that reason, it would probably be safest to limit the total size of the partitions you create to slightly less than 2.2 terabytes, so that all of the subsequent I/O operations are compatible with a 32-bit sector-offset API.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Aug 25 09:15PM +0100 "Dave Platt" <dplatt@coop.radagast.org> wrote in message news:4nc67e-hp.ln1@coop.radagast.org... > size of the partitions you create to slightly less than 2.2 terabytes, > so that all of the subsequent I/O operations are compatible with a > 32-bit sector-offset API.   Pretty sure something nasty would happen if I tried for more than 2.2Gb partition - but I can't even get that.   I was thinking more along the lines of 2x 1.5Tb partitions.

dplatt@coop.radagast.org (Dave Platt): Aug 25 02:34PM -0700 In article <2A%nB.616461$JP7.13240@fx09.am4>, >Pretty sure something nasty would happen if I tried for more than 2.2Gb >partition - but I can't even get that.   >I was thinking more along the lines of 2x 1.5Tb partitions.   That _may_ be workable, but you're probably going to have to do more math, and become more familiar with the PC Master Boot Record and how to hack it.   Setting up the MBR to work in LBA (logical block address) mode, rather than C/H/S, would probably make things easier.   Again, it's going to depend a lot on your PC and its device drivers. If it's capable of accessing the drive in LBA48 mode (with a 48-bit logical block address) you may get away with it. If not, you may be stuck with 2.2 terabytes at most.

Mike Tomlinson <mike@jasper.org.uk>: Aug 25 11:32PM +0100 En el artículo <WJZnB.462838$a64.200548@fx16.am4>, Ian Field <gangprobi   >A 2Tb drive works just fine - I'd even settle for that from the 3Tb >one..........   >Thanks for any help.   This is the wrong group for a start.   3TB requires a GPT partition table, which XP32 doesn't support.   Either use a 2TB drive with MBR partition table (that XP does support), or upgrade to a later version of Windows (7 onwards supports GPT).   -- (\_/) (='.'=) "Between two evils, I always pick (")_(") the one I never tried before." - Mae West

stratus46@yahoo.com: Aug 26 01:30AM -0700 On Friday, August 25, 2017 at 11:10:02 AM UTC-7, Ian Field wrote:   > A 2Tb drive works just fine - I'd even settle for that from the 3Tb > one..........   > Thanks for any help.   If you can live with it as non bootable data only, put it in a USB3 enclosure and use it that way. XP is fine with 3tb USB drives.   G²

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Aug 26 04:28PM +1000 On 26/08/2017 12:08 AM, John-Del wrote: >> Trevor Wilson >> www.rageaudio.com.au   > Free is a admittedly a generous offer Trevor, but can you do better?   **LOL! He wants everything, doesn't he?   -- Trevor Wilson www.rageaudio.com.au

etpm@whidbey.com: Aug 25 11:34AM -0700 Well, this morning the phase converter won't start at all. There is a button that can be pressed that energizes the contactor that connects the 10 starting caps to the motor. This button bypasses the time delay relay that energizes the contactor. Pressing the button has no effect at all, the motor just hums. I don't know yet if the contactor is pulling in or not because I cannot see into the electrics enclosure while throwing the breaker that turns on the phase converter. Even though I can press the bypass button while throwing the breaker I cannot see the contactor. I'll have to get another set of eyes to look inside while I turn the converter on. Getting on subject, I have a DVM that has a capacitance measuring function. Measuring half a dozen known good oil filled caps the readings on the meter match very closely, within one MFD, the value printed on the caps. If I measure the caps in the phase converter and they measure close to the value printed on the case does this mean the caps are probably good? Is there another test I can perform with the meter? And since there are 10 starting caps connected in parallel could just one or two bad caps cause the starting problem? Thanks, Eric

"pfjw@aol.com" <pfjw@aol.com>: Aug 25 12:10PM -0700 Short answer on measuring caps with a DVM is:   If the reading is *NO MORE THAN* 20% higher than the label capacitance it is probably OK.   Lower by more than 10%, it is probably bad.   Problem is that with a VOM with, at best, a 9V battery in it cannot really test a line-voltage cap properly. And leaky caps may give a falsely high reading. So, a 60% over-label reading suggests (not guarantees) it is probably bad.   An ESR meter is better.   And testing a cap at full voltage is best of all.   Bridging in more capacitance is a mixed bag. Does no good if the cap is leaky. Does good if the cap is open.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Aug 25 02:56PM -0700 > could just one or two bad caps cause the starting problem? > Thanks, > Eric   AIUI you could have cap(s) leaking or a faulty switch contacts. Soldering a wire to short the starting switch could tell you which. Obviously don't power the motor for >5 seconds like that.     NT

etpm@whidbey.com: Aug 25 03:15PM -0700 >> Eric   >AIUI you could have cap(s) leaking or a faulty switch contacts. Soldering a wire to short the starting switch could tell you which. Obviously don't power the motor for >5 seconds like that.   >NT Soldering a wire across switch contacts won't work easily because the switch is a contactor. What I'm gonna do is get someone to look at the contactor when I turn on the breaker to see if it pulling in. If it is pulling in then I'll remove it and check the contacts. Then replace them if need be. If the contactor doesn't pull in then I'll need to find out if the coil is bad or if it isn't getting power. I will still need to check the caps if the contactor is working properly. Eric

tabbypurr@gmail.com: Aug 25 08:33PM -0700 > >AIUI you could have cap(s) leaking or a faulty switch contacts. Soldering a wire to short the starting switch could tell you which. Obviously don't power the motor for >5 seconds like that.   > Soldering a wire across switch contacts won't work easily because the > switch is a contactor.   that makes no sense   > find out if the coil is bad or if it isn't getting power. I will still > need to check the caps if the contactor is working properly. > Eric   That might get you there.     NT

etpm@whidbey.com: Aug 25 04:52PM -0700 It looks like the problem wasn't caps after all. Or the time delay relay. While poking around inside the electrics enclosure and putting number labels on wires so that I could remove the contactor I found a female spade connector just hanging behind the contactor coil spade terminal. It's really hard to see the coil connections because it is buried pretty deep and a lot of wires are in the way. So I pushed the spade connector back on and it just slipped on real easy. Too easy. I pulled it back off and wormed the wire through the others and could see that the female connector was open too much. Maybe years of vibration loosened it. So I closed the connector some with pliers and when I tried pushing it on again it was quite tight. After putting the rest of the wiring back in order I tried starting the RPC (Rotary Phase Converter) and it started normally, which is essentially instantly. Now I have another question. Since the spade connector was loose could this have caused a high resistance connection which in turn caused the contactor to barely pull in which then made for another high resistance connection between the starting caps and the motor? I know that at least some types of relays have a higher pull in current than the holding current. So that once they pull in less current is required to keep the contacts closed. In other words a curve of the current required is shaped like a hill, with the holding current past the crest a little. But I think that maybe contactors for motors may work differently because they have so much more travel in the solenoid after the spring loaded contacts first make contact, unlike "regular" low current relays. And since the current required to pull in the contactor remains the same even a slight decrease in current would cause the contactor to drop out. And maybe a low current situation could cause the contacts to make only a light, high resistance, contact. Anyway, thanks for reading all these posts and thanks for the advice given. While writing this post I have started the RPC 6 times and each time it has started normally. Cheers, Eric

Rheilly Phoull <rheilly@bigslong.com>: Aug 26 09:06AM +0800 > and each time it has started normally. > Cheers, > Eric   I would guess that the connector was moving a little each start until it finally came out. The last few times it would make up with the previous start. Generally contactors either buzz - vibrate or close, no in between.

etpm@whidbey.com: Aug 25 11:03AM -0700 <SNIP>   >There is an electronic device that's got its innards potted. It senses >the starting current and when the current drops to the set level it >drops out the contactor that connects the starting caps. <SNIP>   >spinning the rotor, albiet slowly? >Thanks, >Eric     Whoops! I was wrong about the starting device. I just assumed it was some sort of potential relay like I had seen in other motors. It's a bad thing to assume sometimes. In reality the starting device in an adjustable delay solid state relay. The on time, once energized, is from .25 to 5 seconds. It resets when power is removed. Supossedly good for 100,00,000 operations. But the original timer failed after only approximately 600 operations. Eric

ggherold@gmail.com: Aug 25 11:05AM -0700 > Advice? > Thanks, > Eric   Knowing little about converters, it sounds like it could be mechanical? Is it anything like a starter motor with a 'bad' spot? It's hard for me to see how a cap would need two tries to do it's job right.   George H.

etpm@whidbey.com: Aug 25 12:07PM -0700 >spot? It's hard for me to see how a cap would need two tries >to do it's job right.   >George H. Yeah, I'm starting to think the contactor contacts are the problem. Just so you know, a Rotary Phase Converter (RPC) is just a 3 phase AC induction motor that is run from single phase power. Once the motor is spinning it generates power in the third winding, AKA leg, that would normally be connected to a three phase supply. They are started the way many single phase motors are started. A typical type of single phase induction motor has a starting winding that is powered only while the motor is starting. This winding is shifted in phase about 90 degrees from the main winding. Both physically as well as electrically. The electrical phase shifting can be done using resistance, capacitance, or a combination of the two. There are other schemes as well but the capacitance method is common on motors that need lots of torque when starting, like a motor on an air compressor. A simple RPC can be made using just a 3 phase motor. A rope can be wrapped around the motor shaft and then pulled fast to get the motor spinning. Once it is spinning single phase power is supplied and the motor will spin up to operating speed if the shaft was spinning fast enough from the rope pull. Another motor can be used to spin up the RPC motor as well. This motor is then either disconnected mechanically or just turned off once the RPC motor is running. Capacitors can also be used to supply phase shifted current just like a single phase motor. Again, once the motor is up to speed the starting capacitance is disconnected. Even though the RPCs described above will supply 3 phase power the generated power will not be perfectly in phase with the other two phases. And depending on the load the phase shift will vary as will the voltage. So more sophisticated RPCs will use capacitors across the windings to balance the power so that the phases are very close to 120 degrees apart and the voltage in the generated leg is close to the voltage supplied to the motor by the single phase line. That's my simple explanation of RPCs. Eric

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