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jurb6006@gmail.com: Jan 17 09:46PM -0800 Looking for some info on this. Internet searches come up with very little. Normally a tuner I would just ditch the bitch (you know a divorce lawyer used that phrase in his advertising ? lol) but I see one went on eBay for like $79. That is alot for a tuner on eBay. I notice it has selectable IF bandwidth as well. I've only had one or possibly two tuners in my life that had that. I know what it does and that it takes a little doing to put it in as a feature. So maybe this thing is worth fixing.   It does not use any of the usual front ends I recognize. The front end is not integrated PLL from what I see. It is bigger than the usual and it has terminals marked "Vt" and I think "Fosc" or something like that. That indicates the PLL is not in there.   There is very little out there on this thing, one sold on eBay, and there is a monitor or something with the same or similar model number that polluts the web results. So I decided to attack the chipset. What I can see is an LA1247 AM IC, LA1235 FM IF/detector IC, LA3450 stereo decoder IC, two M5218L OP AMP ICs near the audio output jacks and two "c1163" right near the front end. (obviously upc1163)   I can get nothing on these for some reason. Web searches indicate it is equivalent to a Sony 8-759-111-72. They're only a seven or ewight pin SIP through hole. I believe they are probably just OP AMPs but it wod be nice to at least know their pinouts with them being right next to the front end.   Symptom is it pretty much tunes nothing. One time as I am hitting the up button and the display is incrementing though the stations it got something weak but it was at more than one station. Bottom line is that it is not tuning what it is supposed to be tuning.   None of these chips I see are a microprocessor. It might be a surface mount on the bottom of the board or it is might be on the front panel. Thing is I don't see any shielded cable running up there to feed it the local oscillator sample.   That leads me to believe it could be a surface mount on the bottom of the main board.   Why are those obviously unsophisticated ICs right by the front end ? Are they the active filters for the digitally generated tuning voltage ? Perhaps one for AM and one for FM ? Anyone know WTF a upc1163 is ? Or the pinout ? I doubt they are for AGC, but then we are talking NEC. Sometimes they did things a little different. If this tuner is of the vintage I think, they did a little different in it.   The fact that it got a station on multiple station settings, when supposedly being a PLL, means the L in PLL ain't there and it is therefore not Led. Any idea about what I should expect on a scope fron the "Fosc" or whatever that terminal is ? (don't have the unit in front of me right now)I popped the lid and I don't see any ICs in there so I really doubt there is a prescaler of any kind. It is probably a direct sample. Hell, we are talking less than 20 mHz here. It must, however be somehow unloaded from the local oscillator so it can run. That is especially true if they pipe it all the way to the front panel.   I do not even know what year the thing is. Information is that scarce, at least to my searches. The year is not marked on it, rather a date code. Of course that is not the holy grail either, it could have surface mounts on the other side or even be those hybrid boards where they cover the IC with a blob of epoxy type stuff.   I can't say this is a labor of love, but it is something I will do in spare time. It would be nice to have a high end tuner. My one Pioneer tunes really well and I have a Technics that pulls in IHF 0.95 uV. Not that I use it. This, or that or whatever will probably go to my sister because I accidentally cut the dial string in her vintage Marantz. I mean really vintage, not the junk ones. A 2225. I have to order all the lamps for it and figure I'll put it back together so she can at least use the amp for now. So it would be nice to have a tuner. (hmm, there is an Onkyo T-4055 around here she could use that we can't sell because of cosmetic issues, but I still want to fix this thing)   Either way, I am not as concerned that the resale value isn't all that high, I think it might be one hell of a good tuner. If it rivals the tuner in my SX-850 which has been teaked and can pick up a stick in the mud from China, and it has this IF bandwidth doohickey on it, I want it. Why not ? I got three turntables in the house and about five records. No, four, one is on loan from someome else lol.   But this might turn into REAL troubleshooting, and I might find a one meg resistor open or some shit. Like the old days.   Any info you got is appreciated. Even comments unless they are, well you know.   Thanx in advance.

mroberds@att.net: Jan 18 10:22AM > There is very little out there on this thing, one sold on eBay, and > there is a monitor or something with the same or similar model number > that polluts the web results.   You may have seen these already:   One guy on a forum bought one from another guy on that forum. No tech info, but pics of it lit up and working. http://www.audiokarma.org/forums/showthread.php?t=443860   Another guy on that same site was trying to fix one that had a hum in the audio: http://mail.audiokarma.net/forums/showthread.php?p=8337075   From that thread...   "I recapped the power supply and found that the glue used with some of the bigger caps had eaten away the leads of a diode and a resistor. But it didn't hum, so I don't know...just throwing an idea out there."   There are a couple of images of the boards posted in that thread, but you have to be a member of the forum to see them.   A "what's it worth" site that has dates of 1987 to 1989: http://www.usedprice.com/items/audio/nec/tuner/t710-digital-28507.html   Hey, this one has a little bit of technical description: http://fmtunerinfo.com/reviewsM-N.html#NEC   Quoting the above link:   - Thanks to our contibutor Dave N. for this writeup: "The T-710 is a - 4-gang, dual-gate front end MOSFET design, that features copper foil - capacitors. That means that it still sounds like new, after 15 or so - years, and is very quiet. The T-710 has wide/narrow bandwidths, - separate mute/mono switching, fluorescent display, auto and manual - tuning of .2 kHz, calibration tone and auto and preset channel scan. - [...] The specs include usable sensitivity of 10.8 dBf, S/N ratio of - 78 dB stereo and 85 dB mono, image rejection ratio of 80 dB and IF - rejection ratio of 100 dB.   There is apparently a review in Stereophile Volume 12 (1989), issues 9, 10, or 11, but Google Books won't show you the full text for it.   There is also a review in Stereo Review, December 1987 (probably Volume 52 Number 12), per http://www.roger-russell.com/magrevsr2.htm .   If you get desperate, this place has the service manual for $20 plus unknown shipping (they don't know how to run a shopping cart): https://www.agtannenbaum.com/n_cat.htm#NEC   and this has it for $17 + $6 shipping: http://www.stereomanuals.com/man/rep/nec/   Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.   Matt Roberds

walter_evening@post.com: Jan 17 01:18PM -0800 fOn 11/14/2014 12:39 PM, David Farber wrote: > http://www.today.com/video/today/56422860#56416055   "The term stray voltage describes a special case of voltage developed on the grounded-neutral system of a farm and is defined as <10 volts (measured as the root-mean-square value of 50 or 60 Hz alternating voltage, Vrms) between two points that can be contacted simultaneously by an animal (animal contact voltage). The grounding and neutral systems on a farm or in a home wiring system should be properly bonded to ensure electrical safety. As a result, some level of voltage between the grounded-neutral system and the earth (neutral-to-earth voltage) [NEV] is always present as a normal consequence of the operation of properly installed electrical equipment. The term stray voltage is often applied incorrectly to other electrical phenomena such as electric fields, magnetic fields, electric current flowing in the earth (earth currents), or electric current flowing on a grounding conductor (ground currents). Electric currents flowing in the earth or on grounded metal objects will affect animals only if sufficient animal contact voltage is developed."   -- http://www.merckmanuals.com/vet/management_and_nutrition/stray_voltage_in_animal_housing/overview_of_stray_voltage_in_animal_housing.html   ------------------- Many utilities disclaim responsibility in the US and Canada ...   by OE Board - 2008 May 30, 2008 - Farm Stray Voltage: Issues and Regulatory Options. May 2008 ...... distributor is not responsible for variations in voltage from external forces   -- http://www.ontarioenergyboard.ca/oeb/_documents/eb-2007-0709/staff_discussion_paper_20080530.pdf

jurb6006@gmail.com: Jan 17 10:03PM -0800 I just dropped by to mention something since the thread is still kinda alive.   Don't think just going home will save you from electrical shock. there are so many people who doi wiring in houses who don't know WTF they're doing that I would GUESS that the chance of getting electrocuted at home is still more likely than out on the street. I did a bunch of remodeling over the years and have seen the nightmares. I know hat I am doing and got my bona fides frome the toughest electrical inspector in the area, dubbed "Ivan The Terrible". COntractors feared him but he didn't bother me.   Thing is, these stray voltages, they can be more of an indication of the infrastructure getting old. They WERE instaled according to code. Designed to last how many years ? Maybe they have lasted all those years by now. Like an old car. If you got a 1967 Chevy that needs its first new set of ball joints, you got nothing to bitch about to Chevy.   In the Cleveland case I mentioned I suspect someting might have been done wrong and they might have been culpable. Like I said, instead of news after that happened we got all kinds of commercials form the power company on the TV.   But still, that does not prove them culpable. It proves them to havve a public relations department. when thingss go wrong you deal with it either way.   I'd like to sue the asshole who used extension cord to hook up a new outlet in her bathroom. And then hooked it up backwards. That is worse than a regular outlet then, when it trips you no longer SHARE the current with the fault, you get it all.   The things I've seen in residential electric would puthair on your chest, curl it and take it off all in one fell swoop. And as some here can attest, I even thought the story about the phone ringing and the dog barking was a joke.   For real ? For real.

etpm@whidbey.com: Jan 17 10:29AM -0800 On Fri, 16 Jan 2015 17:27:07 -0800, John Robertson <spam@flippers.com> wrote:   >drug like WD in my books. I guess I'm the anti-WDhrist.   >(ducking)   >John ;-#)# WD40 is good for some stuff but it does indeed leave a waxy coating behind when it dries. For this reason it only gets used in my shop for certain things. It does smell good though, which makes it nice to use for rust removal when using it with steel wool or scotchbrite. Eric

"Ron D." <Ron.Dozier@gmail.com>: Jan 17 12:09PM -0800 On Thursday, January 15, 2015 at 12:30:47 PM UTC-5, Bill E. wrote: > What is the best way to remove the corrosion (chemical or mechaical) > and try to keep the shaft as smooth as possible. i will use a teflon > lube when reassembling.     One guy uses reverse electrolysis. Somewhere here: http://zombieengines.blogspot.com/

walter_evening@post.com: Jan 17 01:29PM -0800 At 3:09 PM, Ron D. wrote in sci.electronics.repair:   > > and try to keep the shaft as smooth as possible. i will use a teflon > > lube when reassembling.   > One guy uses reverse electrolysis. Somewhere here: http://zombieengines.blogspot.com/   But, the debris still being there is the issue.

Phil Allison <pallison49@gmail.com>: Jan 17 08:06PM -0800 > WD40 is good for some stuff but it does indeed leave a waxy coating > behind when it dries.   ** Bollocks.   http://www.wd40.com.au/wd-40_faqs     > For this reason it only gets used in my shop for > certain things.   ** Then your are missing out very badly.     ... Phil

jurb6006@gmail.com: Jan 17 10:49AM -0800 Crosspost much ?   Anyway, sometimes there is a difficulty with determining which phase is leading and which is lagging. For (example) a reciprocating compressor it does not matter if it uses reed valves. But other things, it might matter.   Many years ago my Father ran horizontal boring mills. Big uns. One machine he said first of all had shitty coolant flow. What's more every once in a while the impeller of the centrifugal coolant pump would come unscrewed. The company lived with that problem for a long time until he got there and got sick of it.   He figured out that the pump was running backwards. Just switch any two wires and it reverses the motor. Any two, doesn't matter which two as long as it is a delta configuration. There is no reason to use the Y configuration on a little shitcan motor like that.   For some reason the machine itself ran the right way. Go figure, I did not wire it.

walter_evening@post.com: Jan 17 12:36PM -0800 On Fri, 16 Jan 2015 22:50:01 -0600, Martin Eastburn   >Use the two good and a wild for real 3 phase. If you put a computer >on a wild phase you can have issues...   >Martin - 377 three phase in shop from my 208 single phase.   Sure. And just in case you've scared the fire department, maybe here's how to tidy things up to standard per code:   "The high leg service conductor of a 4-wire, 3-phase, delta connected service must be permanently marked orange or identified by other effective means [NEC Article 230-56], and must terminate according to the following: meter termination: ANSI requires termination on the C phase; panelboard and switchboard termination on the B or center phase [NEC Article 384-3(f)]. "

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