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ohger1s@gmail.com: Apr 26 12:55PM -0700 I have a transformer shorted from pri to sec for an industrial CNC machining center. It's in an Aartac type 921A power supply. The XFR is a Wagner + Grimm type EE554 made in Switzerland that I can't seem to locate. Anyone know a source or know of a trusted rewinder I can send this to?

"pfjw@aol.com" <pfjw@aol.com>: Apr 26 01:24PM -0700 > I have a transformer shorted from pri to sec for an industrial CNC machining center. It's in an Aartac type 921A power supply. The XFR is a Wagner + Grimm type EE554 made in Switzerland that I can't seem to locate. Anyone know a source or know of a trusted rewinder I can send this to?   electaudio at cox Dot net Ask for John.   Is a good rewinder, or will 'built-to-suit' at a reasonable cost.   There must be thousands of Hammond off-the-shelf transformers if you do not need multiple secondaries and multiple primaries.   What are the specific needs?   Peter Wieck Melrose Park, PA

legg <legg@nospam.magma.ca>: Apr 26 04:58PM -0400 >I have a transformer shorted from pri to sec for an industrial CNC machining center. It's in an Aartac type 921A power supply. The XFR is a Wagner + Grimm type EE554 made in Switzerland that I can't seem to locate. Anyone know a source or know of a trusted rewinder I can send this to?   You can buy the replacement power supply on-line.   http://www.cnc-shopping.co.uk/aartac-921a-acdc2425-power-supply-24vdc-25a-p-3509.html   If it's running off 240VAC, you could replace it with a generic switcher that fits, or even a linear if there's room. 24V 2A5 out....   RL

John Robertson <spam@flippers.com>: Apr 26 02:00PM -0700 > What are the specific needs?   > Peter Wieck > Melrose Park, PA   Hammond also winds to spec. Expensive, but I've yet to have a Hammond transformer fail that was operated within its design specs.   Not much you can't replace with the Hammond catalogue on hand and not worrying about extra un-needed windings.   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."

oldschool@tubes.com: Apr 27 07:33AM -0400 On Wed, 26 Apr 2017 14:00:33 -0700, John Robertson <spam@flippers.com> wrote:     >Not much you can't replace with the Hammond catalogue on hand and not >worrying about extra un-needed windings.   >John :-#)#   I dont know what a CNC is, or what voltages are needed, but I was recently looking on Ebay for a small transformer and saw more heavy duty industrial ones than I saw the smaller ones.

Andy Burns <usenet@andyburns.uk>: Apr 26 10:01PM +0100 > Don't forget that bane of the electrician's existence: The Arc-Fault Breaker. I gather they are being considered for inclusion in the 18th edition of the (rightpond) IET wiring regulations ...   <http://electrical.theiet.org/wiring-matters/61/18th-edition-report/index.cfm>

"Ron D." <ron.dozier@gmail.com>: Apr 26 03:53PM -0700 Rewiring could possibly increase it, but probably not perceptible. The GFCI/AFCI outlets may draw a bit of current.   Is the OP/TS one of those people you believe that not having on of those child protection caps makes the electricity leak out?   If your going fuse to breaker you might get a break on your insurance.

John Robertson <spam@flippers.com>: Apr 26 04:58PM -0700 On 2017/04/26 3:53 PM, Ron D. wrote: > Rewiring could possibly increase it, but probably not perceptible. The GFCI/AFCI outlets may draw a bit of current.   > Is the OP/TS one of those people you believe that not having on of those child protection caps makes the electricity leak out?   > If your going fuse to breaker you might get a break on your insurance.   If he has Knob & Tube wiring then he may have NO insurance. Of course knob & tube is pre-war (II) and most has vanished, but it shows up in older houses here in Vancouver (Canada).   http://www.carsondunlop.com/resources/articles/knob-and-tube-wiring-home-owners-insurance/   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."

"pfjw@aol.com" <pfjw@aol.com>: Apr 27 04:11AM -0700 On Wednesday, April 26, 2017 at 7:58:39 PM UTC-4, John Robertson wrote:   > knob & tube is pre-war (II) and most has vanished, but it shows up in > older houses here in Vancouver (Canada).   > http://www.carsondunlop.com/resources/articles/knob-and-tube-wiring-home-owners-insurance/   For the most part, those insurance companies tha

thekmanrocks@gmail.com: Apr 27 05:04AM -0700 John Robertson:   If you read back through this thread you will see where I mentioned that the last knob & tube wiring was removed from my house back in the 1980s.

Me, who knows about valves too. <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1068@example.com>: Apr 27 03:37AM responding to http://www.electrondepot.com/repair/transistor-identity-140609-.htm , Me, who knows about valves too. wrote: > arfa.daily At whites, a MFR of metal detectors 8050's were bought in bulk stuck into an automated tester. A bin lamp lit that you through it into. They were an un-classified very inexpensive if 1 amp+ 200MHz part. Your part had this tested, labeled and is a letter of the alphabet instead of "b" plus a 2 digit number. I have LB's of MPSA 5550's and 5123's with gold leads, having betas over 1100. They made crappy three pole oscillators but great touch pad amps for Moog's.

ohger1s@gmail.com: Apr 27 04:31AM -0700 On Friday, June 22, 2012 at 8:55:37 PM UTC-4, Arfa Daily wrote: > result all round, and Christ knows, I needed one of those for a Friday, > after the crap week I've had ... :-)   > Arfa       Except that the S8050 is a PNP and you said that yours checks out as an NPN (and you installed an NPN which works), so any data on that S8050 won't help identifying your part. I'd keep my eye on it a few days before shipping it.

"pfjw@aol.com" <pfjw@aol.com>: Apr 26 10:49AM -0700 > Huh, Well doesn't a paper cap add that certain 'crispness' to the sound? :^)     As in "burnt to a.... "?   Peter Wieck Melrose Park, PA

oldschool@tubes.com: Apr 26 01:33PM -0400 On Wed, 26 Apr 2017 05:28:17 -0700 (PDT), "pfjw@aol.com" <pfjw@aol.com> wrote:   >wicks were dipped multiple times into the solution, picking up a bit of additional > wax each time. the keyword is *DISSOLVED*. Even paraffin wax holds water, >and beeswax is directly water-soluble.   I know a woman who does historical re-enactments. One of her things is making candles. You are right, the wicks are dipped in pure beeswax, (Many times), and each time they get thicker.   I am not sure if you're saying the beeswax is dissolved *IN* the water, or if you mean the container holding the wax is placed in warm water. But to clearify this, there is NO WATER *IN* with the beeswax.   Melting the container of wax with the container in some warm water would likely work. Although she melts her container over a bed of hot coals, which were created by burning wood inside a shallow hole in the ground, surrounded by rocks. There is an iron grill across the rocks, and she has a tin pan between the wax container and the grill (to keep wax from dripping into the fire).   It's a simple but time consuming process. She says the main thing is to keep the temperature right, so the wax stays melted, but dont overheat. That's all accomplished by the spacing between the coals and the wax pot, as well as the coals themselves.   At least now I know what wax is used, (or combination of). The petroleum jelly (vaseline) part seems kind of bizarre, and why that helps with "handling" makes no sense to me. But I'll take your word for it.   So, now we know how water molecules can migrate thru the wax. But that dont explain how they get inside of those old plastic coated caps, (called bumblebees), or similar old caps. Those are sealed real well, unless they develop a crack.

Foxs Mercantile <jdangus@att.net>: Apr 26 02:20PM -0500 > old plastic coated caps, (called bumblebees), or similar > old caps. Those are sealed real well, unless they develop > a crack.   They are NOT "sealed real well." Nor are the old "Micamold" paper dielectric capacitors.   I just re-capped a Collins R-390A receiver. There are 28 paper dielectric capacitors in the one I worked on. About 20 of them were the Sprague bumble bee types, and the rest were Sprague Vitamine-Q.   Go ahead and say it, "Collins! Top of the line! Mil-Spec!" They were still crap capacitors         -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

"pfjw@aol.com" <pfjw@aol.com>: Apr 26 12:32PM -0700 Note the interpolations:     > I am not sure if you're saying the beeswax is dissolved *IN* the water, > or if you mean the container holding the wax is placed in warm water. > But to clearify this, there is NO WATER *IN* with the beeswax.   In the systems I have observed, the wax is mixed into the warm water, and for the most part floats on top - Little actually dissolves, and what does may be partially oxidized material. But there is definitely some that does. What this method does is allow a very thin layer of wax (as little as two inches) will allow full dipping once the wicks have their first coat. The old farmer that demonstrated this to me explained that it was much safer than putting a separate container in water, or, especially, over a fire.   > At least now I know what wax is used, (or combination of). The petroleum > jelly (vaseline) part seems kind of bizarre, and why that helps with > "handling" makes no sense to me. But I'll take your word for it.   It does make sense if you consider the need to make a stable material that is easily spread, and spread very thin, and does not go soft at hand-temperatures (which are generally much lower than the typical tube radio. Paraffin makes the hard base, but does not spread well and needs to be quite hot to melt fully. Beeswax gives the spreading properties, but gets soft, so is used in small quantities. Petroleum jelly (thick, pure oil) prevents the materials from clouding and also reduces sticking to the processing machinery, operating at high speed, mostly. Keep in mind that both the beeswax and the jelly are minor admixtures, > dont explain how they get inside of those old plastic coated caps, > (called bumblebees), or similar old caps. Those are sealed real well, > unless they develop a crack.   This is an easy one. A 'bumblebee' cap seal relies on the interface between two dissimilar materials with vastly different coefficients of expansion. Plastic and metal. Over time, micro-cracks will develop at the leads. Keep in mind that these capacitors live in a tough environment, and can go from freezing to very hot quickly and repeatedly.   The failure mechanisms are common, well understood, and time-sensitive - far shorter than "today". Unless you dabble in instrument amps, meaning that your caps serve as inductors, resistors, and occasionally as capacitors, you have no business leaving these beasts inside anything expected to function.   Peter Wieck Melrose Park, PA

"Michael A. Terrell" <mike.terrell@earthlink.net>: Apr 27 03:01AM -0400 analogdial wrote: > in a few years. So what? Electronics changes fast and the buyer > would almost certainly buy something newer before deteriorating caps > killed the device.     Those oil filled bathtub caps failed, as well. The paper broke down, just like waxed caps, plus the rubber plugs would harden, crack and leak oil.   -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

oldschool@tubes.com: Apr 26 12:33PM -0400 >gender of your XLR connector.   >Reference <http://www.coutant.org/matching/a95.pdf>   >Fred   This amp is strictly a power amp. I plan to get a mixer for it when I find one at a decent price. I dont really need a mixer, since I am using this for a home stereo, but a preamp appears to be needed, and even a small 4 or 6 channel mixer can and will provide that preamp.   On the other hand, maybe my receiver output will have enough preamp built into it (and I suspect it will). But I am aware that matching the impedense should be done. I knew they made such things, but I was not aware they could be purchased in the form of adaptors like these Shure ones. That should be real helpful.   I found out that the inputs are balanced 600 ohm. I am not yet sure what my receiver outputs in ohms. (Have to see if I can find a manual for it). I did however read about some of the (same brand) mixers that are often used with these amps, and they output 600 ohm balanced. Therefore that is a perfect match. One of those mixers, is a 6 channel unit which has 6 XLR connectors for microphones, but Two of those inputs also have a 1/4" jack, called AUX, and there is a switch to use either type (the XLR or the 1/4"). And there is also another switch to set either LOW or HIGH gain. So I'm guessing that those 1/4" inputs can be used to connect something with a high output, such as a receiver, or a DVD player or a Tape Player, etc. And I can only assume that this input can also be used for something like a guitar, when set to the HIGH gain position.   Until I get the XLR connectors I bought online, I cant do much, other than just patch things together. But yesterday I did connect the speakers and stick a direct probe into the XLR holes, connected to my audio generator. It worked like a champ, but I did have to turn the output up as high as it goes on that audio generator, which tells me that it does surely need a preamp.   But even with just a direct test lead jammed in the connector, there was no hum or unwanted noise, and I took it from 10cps all the way to 20Kcps, and it was clear as a bell. (At least from 30cps to 15Kcps). I dont hear above 15Kcps, and at 10cps it just made the speaker cones move and sound like a motor cycle engine.

oldschool@tubes.com: Apr 26 12:59PM -0400 >Reference <http://www.coutant.org/matching/a95.pdf>   This link PDF file is quite useful. But it dont specifically state what devices can be plugged into them. I know there are unbalanced microphones that have a 1/4" plug on their cord, and things like a guitar. But it does not specify if the preamp output from a receiver will match....   One question I have, is there some standardized output (in ohms) for things like the preamp output from a receiver, or the output from something like a DVD or Tape player, or even a small MP3 player? I assume all these devices have some sort of "standard" output impedence, or are they all different?   Most of the time I just hook the stuff up, and if it sounds OK, then I just use it. But I know this commercial equipment, with balanced inputs, is in a class of it's own.......

"pfjw@aol.com" <pfjw@aol.com>: Apr 26 11:45AM -0700 Impedances are guidelines. Not hard absolutes. Most (not all) equipment is remarkably tolerant. Commercial equipment is, typically, more tolerant than consumer equipment, if only because it will get harder use under a wider range of operating conditions.   Put another way, if it sounds good, and nothing gets hot - there you are.   Peter Wieck Melrose Park, PA

Pat <pat@nospam.us>: Apr 26 06:13PM -0400 >Most of the time I just hook the stuff up, and if it sounds OK, then I >just use it. But I know this commercial equipment, with balanced inputs, >is in a class of it's own.......   There is little need to match impedances unless you need to maximize power transfer (for example, coax for radio equipment). Almost everything you run into with consumer audio equipment has hi-z inputs. The outputs are designed to drive those hi-z inputs (which is very easy to do as long as the outputs are lower impedance than what they are driving). The term for this type of signal is line level (as opposed to mics and guitars which can be much lower level). As you have discovered, professional audio equipment uses 600 ohm balanced lines in order to minimize hum and be able to handle longer runs of cable. Any preamp with RCA connectors for its output can drive the hi-z unbalanced input of your amp. If you want to use the 600 ohm balanced input, you need a preamp with that type of output of a converter, but the hi-z inputs (ie, RCA connectors) will work just as well in normal home use.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Apr 27 12:05AM +0100 >Most of the time I just hook the stuff up, and if it sounds OK, then I >just use it.       **********************************************************   Amen.   Most of the time, hooking stuff up just works. Because that what it is designed to do.   All this guff about impedance matching is pretty much irrelevant nowadays, I'm not sure how it made it into this thread.         Gareth.

Phil Allison <pallison49@gmail.com>: Apr 26 05:33PM -0700 > I found out that the inputs are balanced 600 ohm.   ** You are wrong again, the specs say the input impedance is 30kohms balanced, or 15kohms unbalanced.       ..... Phil

Bennett <bjprice@cal.berkeley.edu>: Apr 26 04:02PM -0700 On 4/25/2017 4:04 AM, J.B. Wood wrote:   > Hello, and thanks much for responding. Does your spec sheet indicate > that the chemistry of the #303 is silver oxide or something else? Thanks > for your time. Sincerely, Silver oxide

amdx <nojunk@knology.net>: Apr 26 12:30PM -0500 On 4/26/2017 2:30 AM, gregz wrote:   > I once used a length of copper wire, computed resistance to wire table. > Worked for my test.   > Greg   Yes, so have I, but I'm sure you know, the problem is the resistance varies with temperature. Your current has to be low to avoid heating the wire. Mikek   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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