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Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jun 18 01:53PM -0400 > (Scotch brite) and then tin it.   > I've always wondered what the tenacious oxide is.   > George H.   I don't know. It seems to be some sort of organic crud iirc.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Matthew Connor <connah@gmail.com>: Jun 19 05:46AM -0700 On Wednesday, 17 June 2015 13:30:40 UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   Good morning, Jeff! Thank you so much for your insight. My counter is a Lionel CD V-700 Model 6b, manufacture date 1962.   On one hand, I'm a little confused. You mentioned several times different variations of me having likely "trashed" my counter by doing what I did. At the very end however, when I asked if I had done any harm, you said, "No. They're fine. After all, the counter was probably designed to survive a nuclear attack." So I'm not quite sure that I'm understanding if what I did was bad or not.   On the other hand, you have given me lots of details to consider and suggestions in areas I haven't even started to think about. You've obviously got a great deal of experience and I'll be taking all of your suggestions into account as I move forward with my project. I'll be trying the breath moisture thing right away. Thanks for taking the time to educate an east coast newbie! :) -Matthew

Matthew Connor <connah@gmail.com>: Jun 19 05:47AM -0700 On Wednesday, 17 June 2015 11:58:03 UTC-4, Phil Hobbs wrote: > Briarcliff Manor NY 10510   > hobbs at electrooptical dot net > http://electrooptical.net   Dr. Hobbs: Thank you very much for your insight, sir! It's greatly appreciated! -Matthew

Matthew Connor <connah@gmail.com>: Jun 19 05:48AM -0700 On Wednesday, 17 June 2015 10:20:53 UTC-4, Ralph Mowery wrote: > solder. > It is often recommended to tin the bare copper wires before soldering them.   > I doubt you will get any failure because you scraped off the coating.   Ralph, good morning! Thanks a ton for your input! I'm appreciative! -Matthew

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jun 19 11:10AM -0400 On 06/19/2015 08:47 AM, Matthew Connor wrote:   >> Cheers   >> Phil Hobbs     > Dr. Hobbs: Thank you very much for your insight, sir! It's greatly appreciated! -Matthew   Just 'Phil' to colleagues. The fancy sig block is for SEO purposes. (It works great btw.)   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

captainvideo462009@gmail.com: Jun 18 09:19PM -0700 Just wanted to get back to the group about this AC motor that was running in reverse after being disassembled and then put back together. It turns out that reversing the brushes did indeed reverse the direction of the motor. We can't argue with success, but I still don't fully understand why this is so. Can anyone please explain this to me? Thanks, Lenny

all2001@spambog.com (Wolfgang Allinger): Jun 19 05:14AM -0300 On 18 Jun 15 at group /sci/electronics/repair in article 4f695716-1f25-4b1f-870d-72fb8c3b5cdd@googlegroups.com >the direction of the motor. We can't argue with success, but I still >don't fully understand why this is so. Can anyone please explain this >to me? Thanks, Lenny   Take a DC Motor. The brushes are directly connected to the + - connector. The permanent field is fixed. If you inverse the Batterie, the rotor will run in the other direction.   So do the AC Motor. However the brushes and the field is connected to the mains connector, so changing the mains connector will also change the field, therefor no change between field and rotor.   But you managed reversing by changing the internal brush connection. So the rotor is now to the opposite of the field direction.   Hope my Ginglisch is understandable :)     Saludos (an alle Vernünftigen, Rest sh. sig) Wolfgang   -- Wolfgang Allinger, anerkannter Trollallergiker :) reply Adresse gesetzt! Ich diskutiere zukünftig weniger mit Idioten, denn sie ziehen mich auf ihr Niveau herunter und schlagen mich dort mit ihrer Erfahrung! :p (lt. alter usenet Weisheit) iPod, iPhone, iPad, iTunes, iRak, iDiot

John-Del <ohger1s@aol.com>: Jun 19 03:03AM -0700 On Friday, June 19, 2015 at 5:14:57 AM UTC-4, Wolfgang Allinger wrote:     > Hope my Ginglisch is understandable :)   The sad thing Wolfgang is that your post was far better than some from people whose native language is *supposed* to be English...

all2001@spambog.com (Wolfgang Allinger): Jun 19 06:11AM -0300 On 19 Jun 15 at group /sci/electronics/repair in article 530841b1-2bf4-457f-b82b-033ac2a08453@googlegroups.com   >> Hope my Ginglisch is understandable :)   >The sad thing Wolfgang is that your post was far better than some from >people whose native language is *supposed* to be English...   So these natives should try harder if even a bloody Kraut can outperform them :)     Saludos (an alle Vernünftigen, Rest sh. sig) Wolfgang   -- Wolfgang Allinger, anerkannter Trollallergiker :) reply Adresse gesetzt! Ich diskutiere zukünftig weniger mit Idioten, denn sie ziehen mich auf ihr Niveau herunter und schlagen mich dort mit ihrer Erfahrung! :p (lt. alter usenet Weisheit) iPod, iPhone, iPad, iTunes, iRak, iDiot

Phil Allison <pallison49@gmail.com>: Jun 19 03:23AM -0700 > the direction of the motor. We can't argue with > success, but I still don't fully understand why > this is so. Can anyone please explain this to me?     ** A regular DC motor is surrounded by a *permanent magne*t - right?   If you reverse the external connections to the rotor, it spins the other way cos the relationship between the fixed and moving magnetic fields is reversed.   With your " AC/DC" motor, the fixed field is provided by the same current that drives the rotor. When fed by an AC or DC supply, the fixed and rotor fields always *change polarity at the same time* so the rotation direction remains the same.   You have to go inside and reverse the connection to the field or rotor to effect a change.     ... Phil

John-Del <ohger1s@aol.com>: Jun 19 03:30AM -0700 On Friday, June 19, 2015 at 6:12:11 AM UTC-4, Wolfgang Allinger wrote: > them :)   > Saludos (an alle Vernünftigen, Rest sh. sig) > Wolfgang   If we can only convince them to try harder. They seem to have no will, nor is there any incentive for them to do so.. Seems to get worse as time goes on!   :)

captainvideo462009@gmail.com: Jun 19 06:38AM -0700 > Just wanted to get back to the group about this AC motor that was running in reverse after being disassembled and then put back together. It turns out that reversing the brushes did indeed reverse the direction of the motor. We can't argue with success, but I still don't fully understand why this is so. Can anyone please explain this to me? Thanks, Lenny   Thanks everyone for the great explanations. It makes more sense now. The original owner of this thing apparently tried to replace the brushes himself. I can only surmise that he didn't realize that the bakelite brush holders were held into the housing with small set screws. So he did what any idiot would do. He used a "bigger hammer". Some people should never pick up a tool. It looks like he tried to pry the holders out without releasing the screws and cracked them into many pieces.   The field is connected to the brush holders with push on connectors. That's a good thing too because to get it out he must have ripped it loose from the remnants of the brush holders. Luckily the field wasn't damaged.   At this point he apparently gave up and gave the tool to my son who has been working on it since. So in dis assembly the correct orientation of the field then become unknown, and after replacing the brushes and holders we evidently switched the brush positions.   So he now has the direction problem resolved but the new brushes arc really bad. Perhaps the old ones did too and maybe that's why Mr Wizard tried to replace them in the first place but we don't know.   The commutator does not appear to have worn down much during it's lifetime. A growler test shows no shorted windings to ground, The areas between some of the the segments however appear to be a little ragged and opened a bit from the arcing, no doubt. A dial indicator on the commutator shows an out of round condition totaling 1.5 thousandth's, on each side for a total of three thousandth's for the entire piece. According to a machinist we consulted this doesn't seem like enough to warrant turning the commutator, but I've been considering something else. With this motor spinning at 9000 RPM would a 1.5 thousandth's out of round condition be enough to "bounce" the brushes and make them arc? Brushes and holders are new and each brush is mounted stationary, and it's relationship to the position on the commutator cannot be altered. I can't figure out what else could be causing this? Lenny

John Robertson <spam@flippers.com>: Jun 18 12:38PM -0700 On 06/17/2015 5:37 AM, Matthew Connor wrote:   > Any suggestions geared towards a newbie would be greatly appreciated. Thanks, all!   > Kindly,   > Matthew Connor   You can always encapsulate it in two part epoxy. MG Chemicals (and others) sell these kits.   Mind you you won't be able to easily remove the encapsulation later unless you soak the blob in acetone for a day or two to soften the epoxy...   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."

Matthew Connor <connah@gmail.com>: Jun 19 05:56AM -0700 > rocks may be more radioactive as well as concrete. Some green > glassware and some glazes on ceramics are radioactive. > Eric   Eric, thanks so much for your input! Based on your response and on Jeff's, it's obvious I should have included more detail. My apologies! This is a Lionel CD V-700 Model 6b manufactured in 1962. I do not know what type of material the PCB is made from for certain but I'd like to find out. If I included a picture, would that help?   As for its condition when I received it, it was in bad enough shape (PCB-wise) that I had to rebuild it. Many of the wires had all but one or two strands broken loose from their respective solder joints so relatively speaking, a lot of electricity was going through very little conductor. Because of the way those and some other components broken, I am suspecting shock as the primary cause, thus leading me to ask about this modification. I will certainly take your thoughts into account. I'm very grateful. Thanks again! -Matthew

Matthew Connor <connah@gmail.com>: Jun 19 05:57AM -0700 On Wednesday, 17 June 2015 13:10:06 UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   Hi, Jeff! Sorry for the lack of details. This is a Lionel CD V-700 Model 6b manufactured in 1962. I like the grommet idea very much...thanks! -Matthew

Chuck <chuck@mydeja.net>: Jun 19 08:01AM -0500 >rocks may be more radioactive as well as concrete. Some green >glassware and some glazes on ceramics are radioactive. >Eric     If you happen to have any Pentax or Carl Zeiss Jena lens from the 60s that have turned yellow, they are a good radiation source for testing a Geiger counter.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Arfa Daily" <arfa.daily@ntlworld.com>: Jun 19 02:31AM +0100 I currently have a Peavey PVX-P12 amp chassis on the bench. There was no audio at all from either the HF or LF digital output ICs. The IC in question has a 'go / mute / standby pin and this pin on both ICs is connected to a little control circuit. That in turn is driven by the "AC Detect" circuit on the power supply. This bit of circuitry is very straightforward, and comprises a bridge fed with AC from the line input, via a 0.47 uF 275 v ~ x-class cap. Across the output of the bridge, are two caps in parallel, shown on the schematic as being 22uF at 25 v working. But here's the thing. They are not shown as being polarised, nor is there any marking that I can see on the caps themselves, that indicate any polarity. They are surface mount and small - approx 3.6 x 2.6 x 1.8 mm - and look just like a typical sm ceramic cap. Pink-y glazed body with conventional 'end caps'. One of these two capacitors is short circuit. With it removed, everything returns to normal, and the amps both un-mute. The circuit only produces a few volts, and this is used to drive the LED in an opto via a 47 ohm R, the transistor side of the opto being the "AC Detect" signal that connects to the mute control circuit on the amp board.   So what type of caps are these ? They seem awfully small for any kind of solid dielectric non-polarised cap of that value, and that sort of voltage rating. I've had a look around at a few component supplier's offerings, and can't find anything that seems to match. I checked the capacitance of the one that isn't short, and it came up at 18 uF, so a bit low, but in the ballpark of what it says on the schematic. Given that these caps only seem to serve as the filter for the bridge output, and that there is only a few volts across them in normal operation, can anyone see any potential problems with replacing them with a pair of 'conventional' 22 uF 16 v polarised tants, obviously taking care to put them the right way round ?   Arfa

Phil Allison <pallison49@gmail.com>: Jun 18 07:56PM -0700 Arfa Daily wrote: > solid dielectric non-polarised cap of that value, and that sort of voltage > rating. I've had a look around at a few component supplier's offerings, and > can't find anything that seems to match.   ** I found lots - eg:   http://www.newark.com/murata/grm32er61e226me15l/ceramic-capacitor-22uf-25v-x5r/dp/24R6350       > volts across them in normal operation, can anyone see any potential problems > with replacing them with a pair of 'conventional' 22 uF 16 v polarised > tants, obviously taking care to put them the right way round ?   ** Should work fine. The SMD caps are cheaper than tants of the same ratings.     .... Phil

N_Cook <diverse@tcp.co.uk>: Jun 19 07:48AM +0100 On 19/06/2015 02:31, Arfa Daily wrote: > 'conventional' 22 uF 16 v polarised tants, obviously taking care to put > them the right way round ?   > Arfa   Why would they have to be unpolarised? Just 2 paralleled together to get the required capacitance. Any polarising mark on the SM carrier strip perhaps

"Arfa Daily" <arfa.daily@ntlworld.com>: Jun 19 08:49AM +0100 "Phil Allison" <pallison49@gmail.com> wrote in message news:d1c37f77-0764-47d7-aa2c-872280577727@googlegroups.com... >> can't find anything that seems to match.   > ** I found lots - eg:   > http://www.newark.com/murata/grm32er61e226me15l/ceramic-capacitor-22uf-25v-x5r/dp/24R6350     Thanks, Phil. Oddly, I searched in Farnell, which is basically the same company as Newark, and these caps did not appear. But sticking the Murata part number into the Farnell search engine - there they are. Just goes to show that what I have always said - that Farnell's product searcher is useless - has been borne out again ... >> with replacing them with a pair of 'conventional' 22 uF 16 v polarised >> tants, obviously taking care to put them the right way round ?   > ** Should work fine.   Yeah, I thought so. The guy is hoping to use it tonight so I think I will just go with the tants   Arfa

"Arfa Daily" <arfa.daily@ntlworld.com>: Jun 19 09:04AM +0100 > Why would they have to be unpolarised? Just 2 paralleled together to get > the required capacitance. Any polarising mark on the SM carrier strip > perhaps     I don't think that they *do* have to be un-polarised, as such, given the ones that Phil has found. I think it's just because they *are*, if you see what I mean. To be honest, I never knew that you could get multilayer ceramics in such high values. Presumably, they don't go up as high as 47 uF which the designer felt he needed, so he just put 2 x 22 uF in parallel instead. As I said, the circuit is absolutely un-critical in that it only needs to produce a small amount of DC from the incoming mains to power the LED in the opto that produces the muting signal. Because of time constraints with ordering-in those ceramics, I think I'm just going to go with a pair of small tants, fitted to observe their polarity.   Arfa

John-Del <ohger1s@aol.com>: Jun 19 03:12AM -0700 On Friday, June 19, 2015 at 4:04:09 AM UTC-4, Arfa Daily wrote:   > I don't think that they *do* have to be un-polarised, as such, given the > ones that Phil has found. I think it's just because they *are*, if you see > what I mean.   That's correct. They are not polarized because that's the technology. Electrolytics are generally polarized because that's the tradeoff in the technology at the time. You can always use a non polarized cap in place of a polarized.     >To be honest, I never knew that you could get multilayer > ceramics in such high values.   The first time I ran across these caps was about 10 years ago in LCD TVs on the tcon board. Six to ten paralleled in a bypass on the main dc-dc convertor to give several hundred uf of capacitance. Take up no room at all. Not as short happy as tants but they short more than typical electrolytics.   Because of time constraints > with ordering-in those ceramics, I think I'm just going to go with a pair of > small tants, fitted to observe their polarity.   If they fit and you can keep the leads short, no problem.

N_Cook <diverse@tcp.co.uk>: Jun 19 11:36AM +0100 On 19/06/2015 09:04, Arfa Daily wrote: > just going to go with a pair of small tants, fitted to observe their > polarity.   > Arfa   So to get that capacity in that package , they must be seriously multi MLCC. Was it actually dead short or very low resistance. I suspect the usual metal migration failure mode of MLCC , then paralling-up just increases the chance of failure , for the circuit. Someone mentioned paralling ten , asking for trouble.

N_Cook <diverse@tcp.co.uk>: Jun 19 12:00PM +0100 On 19/06/2015 09:04, Arfa Daily wrote: > just going to go with a pair of small tants, fitted to observe their > polarity.   > Arfa   So to get that capacity in that package , they must be seriously multi MLCC. Was it actually dead short or very low resistance. I suspect the usual metal migration failure mode of MLCC , then paralling-up just increases the chance of failure , for the circuit. Someone mentioned paralling ten , asking for trouble.

dougnlizt@gmail.com: Jun 18 11:35AM -0700 > I tried but it won't even let me turn it off like that   Though I'd share my experience with my first (and last) Harman Kardon product...   I bought this a couple years ago from Best Buy. After some months of buying the AVR-1700, a 'BCO Update Please Wait...' message came up, essentially locking the receiver. Following the reset steps didn't work... leaving it powered off for a long period didn't help. After much google searching and working to find a solution, I tried to update the firmware. Because of work and family obligations, this self-fix-it troubleshooting took me a couple months before I finally decided to take it back to Best Buy.   But... alas... it is out of warranty.   My continued searches discovered that I was not alone... several others experienced the same issue, with no help from Harman Kardon. I finally came across a work around (posted here) that walked me through how to 'pretend' to update the firmware (it always says 'failed'), but this process alone does some sort of 'reset', and the receiver begins working normal again.   We sort of got used to this 4-6 month ritual of resetting the receiver when this message would appear. However, I suddenly lost video. Sound was there, but no video output (HDMI - I didn't try the other outputs) from the receiver. At all. I decided to buy a $20 optical cable to at least allow me to connect my HDMI resources to the TV then pipe the sound from the TV to the receiver. But... guess what? Getting the 'BCO Update' message suddenly. Coincidence? Doubtful.   I tried our tried-and-true method of resetting the receiver. Did not work. BCO Update message will not go away.   I can honestly say I have exhausted nearly every available resource to get the AVR-1700 working, to no avail. Contacted the Harman Kardon 'tech support', who directed me to contact a local service place. I called them, and they said $40 to do a diagnostic, and from my description he's guessing between $150 and $200 total to get it working again.   I'm excited to get home today and try out my new Yamaha receiver that just showed up today!   I think that if Harman Kardon had taken more responsibility for this product and corrected the problem, I would feel differently. However, with the experience I have had, Harman Kardon is unfortunately no longer a list of future viable options. On top of that, my children now feel the same way I do, having witnessed my quiet fits of rage with this product.   As of this moment, the Harman Kardon AVR-1700 is officially a boat anchor... now all I need is a boat...   You may ask, "Why is this guy writing us all this stuff?" It's because I believe in making ourselves better. Without feedback on experiences such as this, how can we possibly improve? I do want Harman Kardon to succeed -- I think it is a great looking, sounding product. I wish they would stand by their product when there is a seriously obvious issue.   If you are experiencing the same thing I am, I suggest you stop wasting your time with trying to fix it and just 'start over' with something else. Good luck to you all!

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