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Robert Bannon <rbannon@yahoo.spam.nowhere.invalid>: Nov 15 12:40AM I want to fix a half dozen or more 120VAC (USA) extension cords, all with molded on connectors, both male and female by putting on something like this: http://www.parts-express.com/Data/Default/Images/Catalog/Original/110-403_HR_0.jpg   I'd like to replace them with those big fat meaty ones like those you see in a hospital. https://static.grainger.com/rp/s/is/image/Grainger/5A076_AS01   Googling, they're pretty expensive at $20 to $40 each! https://www.grainger.com/category/ecatalog/N-1z0dqef   Lowes has not as good ones for $5 to $7 each: https://www.lowes.com/pl/Electrical-plugs-connectors-Cable-wire-connectors-Electrical/4294722553   Just curious if I can get the hospital grade plugs at about the Lowes price?   Any suggestions?

philo <philo@privacy.net>: Nov 14 06:51PM -0600 On 11/14/2016 06:40 PM, Robert Bannon wrote:   > Just curious if I can get the hospital grade plugs at about the Lowes price?   > Any suggestions?   Probably better to replace the whole cord but if you do replace either the plug or receptacle do not cheap out.   I used such things on my job. Since I retired a few years ago I forgot which brand names are which but those black and white ones will last for years. The yellow ones can melt.

Ed Pawlowski <esp@snet.net>: Nov 14 07:52PM -0500 On 11/14/2016 7:40 PM, Robert Bannon wrote: > https://www.lowes.com/pl/Electrical-plugs-connectors-Cable-wire-connectors-Electrical/4294722553   > Just curious if I can get the hospital grade plugs at about the Lowes price?   > Any suggestions?   You won't. Amazon has them cheaper than Grainger though. Everyone has them cheaper than Grainger.

jurb6006@gmail.com: Nov 14 01:51PM -0800 Oh boy, that's a blast from the past.   First a couple of comments after I tell you - I do not remember it all. First of all it is a very good point to point system. Second of all I would NEVER give this info out back when these things were being serviced still because they are very stable and you usually never have to touch them unless you change a CRT. (or possibly the whole convergence unit due to a coolant leak) So therefore you need to tell me WHY you need to do this. Did you change a CRT ? Did you transplant a projection box into a different cabinet ? Did you change te convergence module ?   WARNING - these things save settings on the fly. If you discover it is not responding correctly aqnd you did something wrong there is NO going back even if you unplug it. Unnastand ?? If it does not respond correctly that makes it harder to fix because as you do the actual repair you do not know if you have it fixed or not.   And to even do it you need an original remote or a select few universals (RCA from that era) or you simply cannot. newer RCA remotes even for the older newer ones won't do it.   Oh, and one other reason to do it is if you replaced the flyback with an aftermarket part, they have shorter retrace time and affect geometry, specifically the horizontal width. In that case, stay out of the convergence and just adjust the chassis width until the vertical lines converge at the sides. That is easier even though you have a different problem - the main service menu is not labelled. You need the list of parameters. Otherwise you are liable to change something you do not want to change. I don't remember how many there are but there are enough not to memorize. I could determine it o the fly, by adjusting each one and returning it to its original parameter, which they give you on the right side. On the left you get "P:_" which is the parameter, on the right you get "V:_" which is the numerical value of that parameter. Those also save on the fly.   Tell e why you need to adjust this and I will search my PC for the files, if I even still have them. But I can retrieve quite a bit from memory.   Those things are a fantastic design, if they had not been obsoleted by flat screens ad those eljunko LCDs and DLPs they would be worth putting money into today. Their only big problem is the power supply on the main chassis. When the main chopper blows it takes out so many (SMD)parts it is simply not worth it. I have actually cut the PC board in that area and inserted a PS from another unit, which is actually not all that hard but has to be done right. You have to know where to cut.   So, what is the symptom/situation ?

ohger1s@gmail.com: Nov 14 02:59PM -0800

ohger1s@gmail.com: Nov 14 03:01PM -0800 > Looking for how to get into the menu for fine adjustment of convergence on a rca P60908. Thank Ted   I have the procedure, but I don't like folks running around in the service menu. This TV was very well designed but one parameter bumped too far and out she goes.   Later versions of the 195 had a limited point to point convergence in the customer menu. This was very similar to the service menu procedure but wouldn't allow you to play deep in the corners in order to avoid overstressing the conv outputs. See if your model has this.

jurb6006@gmail.com: Nov 14 04:13PM -0800 > > Looking for how to get into the menu for fine adjustment of convergence on a rca P60908. Thank Ted   > I have the procedure, but I don't like folks running around in the service menu. This TV was very well designed but one parameter bumped too far and out she goes.   > Later versions of the 195 had a limited point to point convergence in the customer menu. This was very similar to the service menu procedure but wouldn't allow you to play deep in the corners in order to avoid overstressing the conv outputs. See if your model has this.   I still want to know why he wants in there. There are only so many reasons, as you most probably know. they do not just drift. Is it just one color ? If so, beat around the convergence board for loose connections and if anything moves, solder it. If it is two colors, look into the main chassis geometry. If it is all three colors then does it have pincushion distortion ? I so the convergence PS is not starting and that is because of a rectifier and filter on there, and many times that failure is a coolant leak. Sometimes though it is just a filter cap. That source runs off the flyback IIRC and that is the only place they could have tapped it off because the main SMPS runs all the time.   I agree, no divulging such information unless they demonstrate they are either a tech that understands not to try to adjust out a problem or at least someone who can comprehend it. And I still want a reason why. THEY DO NOT DRIFT !   Actually if you remember, NAP eventually gave the customer much more multipoint convergence control. And they would try to adjust out faults related to the STKs, some of them did't just short out. (remember those ? you just unplug that one plug and hear HV and you knew what it was)But after the repair I saw all kinds of things people did, fortunately they provided a factory restore and that usually fixed whatever damage they did to the data. Those RCAs had no such feature. Let that be a lesson in trepidation to this person. You can't just come in here asking for that. I do not prefer to help people screw things up.   Know what you NEVER want to tell anyone, even a competent tech ? How to get into a Pioneer. Those menus are so unfriendly I left them alone whenever possible. I fact I left them all alone if possible. None of this stuff drifts. Greyscale maybe but still on some units forget even that.

etpm@whidbey.com: Nov 14 10:38AM -0800 All, I know almost nothing about tubes(AKA valves). My son bought a capacitor discharge spotwelder that uses tubes. It doesn't work. Parts of it do but on the whole it appears that it doesn't charge the caps. There are three types of tubes in the thing. 3 each OA2WA voltage regulators 2 each 2D21 thyratrons 1 each 5U4GB rectifier There are also 6 each physically large electrolytic caps that are, I believe, rated for 450 volts. They are made by Sprague and are marked 200-450. No uf markings though. Apparently a couple rattle when shaken-probably not a good sign. There are two transformers. The first has many taps and the second is connected through a relay to the bank of caps. The secondary of this xmfr is the spotwelder output. As near as I can tell the circuit basically operates like so: The first xmfr provides 450 volts AC which goes through the 5U4GB tube to be rectified and then through three OA2WA tubes which are connected in series. From there the power goes to the cap bank and charges the caps. And from the caps through a big relay to the output xmfr. The OA2WA tubes have only two of the pins connected. So power goes in one pin and then out the other to the next OA2WA tube and so on. It looks like there is no output from the last tube in the series. So maybe this is why the caps won't charge. At least one 2D21 thyratron seems to work because the relay that connects the cap bank works when the machine is triggered. I would like to know how to test the tubes without a tube tester. Maybe this means I will need to make a tester. I also would like to know how to test the big caps. My meter has a cap test function but it doesn't seem to work with these big caps. Maybe this is because the caps are high voltage types. Is it (fairly) safe to attempt charging the caps with line voltage (120 volts) by first rectifying and then passing the current through a resistor and then to the caps? Here is a link to pics my son took of the guts of the spotwelder: https://goo.gl/photos/LF4JKeGyA4YWiCwv9 Any comments about the spotwelder would be much appreciated. Thanks, Eric

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 11:12AM -0800 First, where are you? All the tubes you mention are quite common and not very expensive. I probably have all of them in my rather random connection. The bigger issue are those capacitors.   Please note the interpolations.   > I believe, rated for 450 volts. They are made by Sprague and are > marked 200-450. No uf markings though. Apparently a couple rattle when > shaken-probably not a good sign.   200uF @ 450V. You could pay anywhere from $15 to $100 for those caps. Given the application, do not cheap out, but get as high a quality as you can afford. You also have the choice to put caps in parallel to make the capacity - and series/parallel to make a higher working voltage. There is plenty of room given the size of modern caps to go this route.   > in one pin and then out the other to the next OA2WA tube and so on. It > looks like there is no output from the last tube in the series. So > maybe this is why the caps won't charge.   It is probably a blessing that your rectifier (5U4) tube does not work. Were you to be passing B+ - well, the results may be unhappy - see below.   > At least one 2D21 thyratron seems to work because the relay that > connects the cap bank works when the machine is triggered. > I would like to know how to test the tubes without a tube tester.   Other than for filament continuity and gross shorts (shorts on a cold tube), no you have no certain way to test tubes without a tester.   > Any comments about the spotwelder would be much appreciated. > Thanks, > Eric   The big caps are toast - full stop. DO NOT EVEN TRY to operate the tester without them as it is possible to do permanent damage to the transformers if the caps are shorted.   If you are anywhere near the Melrose Park section of Cheltenham Township (Philadelphia area) let me know. Despite the size and industrial application, this is a fairly basic issue to troubleshoot.   Now, showing my age, I used one of those ancient beasts some 40 years ago when I was working as a machinist. When set up properly, they are amazingly versatile. I used one to weld various thickness of inconel wave washers and pimple washers onto stainless steel seal backs for aircraft and nuclear applications. From stuff that was almost as thin as paper (0.004 thick) to stuff as thick as index card stock - dial in the machine, pass the pull-tests and it would hold the setting, effectively, until changed. There was a small stash of tubes above the machine - but no 2D21s. When one of them died one way, I found it at Leon Fertik's establishment for $1.50. I replaced them both and purchased two spares. The machine shop is still with us and thriving. Leon, sadly gave up his shop after his wife passed.   Best of luck with it - I can think of a lot of uses.... Especially if your son is an artist.   Peter Wieck Melrose Park, PA

etpm@whidbey.com: Nov 14 11:52AM -0800 On Mon, 14 Nov 2016 11:12:07 -0800 (PST), "pfjw@aol.com"   >Best of luck with it - I can think of a lot of uses.... Especially if your son is an artist.   >Peter Wieck >Melrose Park, PA I'm north of Seattle on Whidbey Island so a visit would be unlikely. My son has tried to power the thing up and even though parts do work it won't do any welding. There is no odor of magic smoke so I think the xmfrs are both OK. I told my son not to power it up any more until we figure out what's wrong with the thing. The welder has two ranges: 0 to 20 watt seconds and 0 to 200 watt seconds. And my son has uses for both ranges. Since I sorta talked him into getting a spot welder like this one I kinda need to make sure we get it up and running. Thanks for the advice and cap ID. Eric

John Robertson <spam@flippers.com>: Nov 14 11:57AM -0800 >> in one pin and then out the other to the next OA2WA tube and so on. It >> looks like there is no output from the last tube in the series. So >> maybe this is why the caps won't charge.     I suggest you consider PHOTOFLASH rated caps - they have a very fast discharge (low internal ESR - you might want to get a Blue ESR meter to test these caps) and aren't too expensive...   http://ca.mouser.com/Passive-Components/Capacitors/_/N-5g7r?Keyword=photoflash&FS=True   Look up REFORMING capacitors. Even old ones like yours may be saved, there was a recent thesis published that showed how large value caps can last a long time if they are reformed carefully.   2D21's are very old design - there are many circuits online to replace them with SCRs if you want to bring the machine up to the 21st century...   Likewise your 5U4s, this can be replaced with a solid state bridge (dual diode) rectifier. As the 5U4 has its own transformer then you need to make sure it is fused correctly on the primary side in case of a shorted diode.   OA2 tubes are 150VDC regulators, so with three of them the output is regulated to 450VDC. If the OA2s are glowing purple then they are at their regulated voltage (more or less) - all three need to be glowing for your 450VDC to be regulated. I would expect them to be across the output of the 5U4 to ground to regulate the output voltage...   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>: Nov 14 12:14PM -0800 > like this one I kinda need to make sure we get it up and running. > Thanks for the advice and cap ID. > Eric   Yeah - that is a bit distant, for now. I did get a chance to visit one of the participants herein in his native habitat (central Texas) recently, so, stranger things have happened.   At this point:   a) Focus on the caps. Get them replaced with caps rated, either singly or in combination at 200uF @ 450V minimum. Some basic rules of thumb: Caps in series are additive for capacity, but not for voltage. 10 x 20uF @ 450V (IN PARALLEL) = 200uF @ 450V.   Two caps in series must be calculated, but keeping it very simple, if two 20uF @ 450V are connected in series, the actual capacitance will be 5uF @ 900V. You may see the calculations here: https://www.kitronik.co.uk/blog/how-to-calculate-capacitors-in-series-and-parallel/   b) Test the tubes by checking the filaments and for any dead shorts internally when cold. A base diagram will tell you which are the filament pins, and then any pin to any pin not internally connected (also given on the base diagram) for shorts.   There are lots of sources for tubes - if you get stuck, let me know and I will root through my spares box. I have 0A2s and 5U4s, most likely in some quantity. As to 2D21s I am not sure, but they are stocked at Antique Electronics Supply (AES) for $5 or so.   Then, your best friend is cleaning anything that can be cleaned without damage. Dust removal, correct lubrication if applicable, rust removal (Beware of steel wool!) and similar.   Best of luck with it - given that you are in the PNW, and, worse, on an island, make sure that you keep the system dry and free of salt. Given the operating parameters of that beast - you DO NOT want stray currents floating around.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 12:20PM -0800 Forgive the top posting but WARNING: if a big honking electrolytic capacitor that is more than 60 years old is rattling when shaken, it is absolutely and irredeemingly, irrevocably TOAST. As are its siblings. Reforming is an exercise in futility, and possibly very dangerous, as if by some chance you do actually reform one (or more) for the moment, and it should fail under actual use, all the work previous would be for naught. **POW**.   Agree on the photoflash caps in any case. However, I suspect that the OEM caps are vastly oversize to make up for their rather slow chemistry.   Peter Wieck Melrose Park, PA   On Monday, November 14, 2016 at 2:57:48 PM UTC-5, John Robertson wrote:

John Robertson <spam@flippers.com>: Nov 14 12:36PM -0800 > Agree on the photoflash caps in any case. However, I suspect that the OEM caps are vastly oversize to make up for their rather slow chemistry.   > Peter Wieck > Melrose Park, PA   I hear what you are saying Peter, but those caps are industrial grade caps, not what you would find in a radio. Agreed the shake test will tell if they are really bad (no rattles!), however attempting to reform them is not an exercise in futility unless there are obvious signs of venting around the rubber plug on the top of the can.   If you have access to an ESR meter that will give you a pretty good idea of the capacitors condition. We sell the Bob Parker kit (as do others) and using that with an ohmmeter to see if the low ESR is an actual short circuit or not will give you a pretty good idea of the condition of these electrolytic caps.   These would have been photoflash rated caps originally and they were common in photographic gear from the 50s and on. My dad's architectural photography studio had many flash boxes that used racks of those caps, back in the 50s/60s and 70s.   John :-#)#   PS, I forgive the top-posting (ducking)     -- (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>: Nov 14 12:56PM -0800 On Monday, November 14, 2016 at 3:36:25 PM UTC-5, John Robertson wrote: > back in the 50s/60s and 70s.   > John :-#)#   > PS, I forgive the top-posting (ducking)   I keep "that" ESR meter, and it is extremely useful. I also have a neat little cap tester that actually tests caps at full operating voltage (up to 450V, that is). It is quite interesting to see caps that seem to test OK in the short term, but over time start to get *warmer* and *warmer* until that **POW** actually happens. It may take an hour or two... When I find one of these, I will hang it (connected) in a Home Depot bucket outside and wait ;-)>   My point is that a capacitor, even half-a-dozen capacitors are usually pretty cheap if measured against the alternative failing at a critical moment. These are not the typical cap found in the typical radio - there is a LOT of energy stuffed inside those beasts. Too many for me to trust a 50+ year old cage for containment.   Peter Wieck Melrose Park, PA

jurb6006@gmail.com: Nov 14 01:12PM -0800 >"Two caps in series must be calculated, but keeping it very >simple, if two 20uF @ 450V are connected in series, the >actual capacitance will be 5uF @ 900V. "   That's not what I "heard". It should be 10 uF.

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 01:26PM -0800 > >"Two caps in series must be calculated, but keeping it very >simple, if two 20uF @ 450V are connected in series, the >actual capacitance will be 5uF @ 900V. "   > That's not what I "heard". It should be 10 uF.   (C1 x C2) / (C1 + C2) = Working Capacitance is the equation I have used these many years.   Example 1:   10 x 10 = 100 10 + 10 = 20 100 / 20 = 5   Example 2 (from the link):   10 x 22 = 220 10 + 22 = 32 220 / 32 = 6.875   At least where I come from.   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: Nov 14 04:46PM -0500 In article <6fc1c49e-9ee2-4471-8eaf-7746c5246c9c@googlegroups.com>, pfjw@aol.com says...   > At least where I come from.   > Peter Wieck > Melrose Park, PA     If equal value capacitors are in series (same for resistors in parallel) all you have to do is devide the value of one of them by the number. That would be 20 devided by 2 for 10.   You can also take the long hard way and do the product over the sum as in your example. You just need to LOOK AT THE VALUE IN THE EXAMPLE AS BEING 20 INSTEAD OF THE 10 FOR EACH ONE THAT YOU USED.   For equal values of capacitance the voltage will add, if the voltages are not equal then there are problems. Resistors are needed across the capacitors when equal values of capacitors are used. This is mainly due to the wide variation of capacitance in most of them. Helps to bleed off the stored charge also.

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 01:58PM -0800 On Monday, November 14, 2016 at 4:46:42 PM UTC-5, Ralph Mowery wrote: > capacitors when equal values of capacitors are used. This is mainly due > to the wide variation of capacitance in most of them. Helps to bleed > off the stored charge also.   OK - I have enough stray caps at home to do a lash-up and I have enough very accurate meters to test the actual results of that lash-up. But, I just rebuilt the power-supply of my Dynaco ST-70 and my actual working results were as the equation implied, as I remember.   Nor would I ever run caps of differing voltage in series. Or parallel for that matter.   I will report my results.   Again, here is the link. I am NOT making this up.   https://www.kitronik.co.uk/blog/how-to-calculate-capacitors-in-series-and-parallel/   Peter Wieck Melrose Park, PA

Adrian Caspersz <email@here.invalid>: Nov 14 10:07PM > I will report my results.   > Again, here is the link. I am NOT making this up.   > https://www.kitronik.co.uk/blog/how-to-calculate-capacitors-in-series-and-parallel/   Read Ralphs post again?   Example 1:   C1 = 20, C2 = 20   not 10 ...   -- Adrian C

John Robertson <spam@flippers.com>: Nov 14 02:11PM -0800 > https://www.kitronik.co.uk/blog/how-to-calculate-capacitors-in-series-and-parallel/   > Peter Wieck > Melrose Park, PA   The previous poster was simply pointing out that you made an error in your math. You had a 10uf and a 20uf cap as your math components based on the link, but were speaking of two 20uf caps in series in the preceding text.   20*20=400 20+20=40 400/40 = 10uf   For two identical value caps in series divide be two for the resulting capacitance. Voltage is added. If there are differences in the capacitance between the two caps then the formula is needed.   Hey, we all make mistakes, even I've made one or two (a minute)...   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."

etpm@whidbey.com: Nov 14 02:45PM -0800 On Mon, 14 Nov 2016 12:20:23 -0800 (PST), "pfjw@aol.com" >> (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) >> www.flippers.com >> "Old pinballers never die, they just flip out." I found 220 mfd 450 caps at JustRadio.com. I'm not sure if these will discharge fast enough. I emailed the site and am waiting for an answer. A quick search for photoflash caps turns up 300 volt caps, no 450 volt caps. So I'll wait to see if Just Radio thinks its caps are up to the job. I have decided to just change out all the caps in the thing if the correct main big caps are available at a reasonable price. I don't think I want to go through the trouble of coming up with solid state solutions and then rewiring the unit just yet. If it worked that well in the past with tubes and if they have reasonable lifetimes I'll just keep it the way it is. On the other hand, it is my son's machine and he can do whatever he wants with it, no matter what kind of help dad wants to give. Eric

Ralph Mowery <rmowery28146@earthlink.net>: Nov 14 06:15PM -0500 In article <q5fk2cppqo2i0v69gdvdcq3bu5f147u9b7@4ax.com>, etpm@whidbey.com says...   > >> "Old pinballers never die, they just flip out." > I found 220 mfd 450 caps at JustRadio.com. I'm not sure if these will   The 220 mfd will work fine where the 200 mfd caps are used. Many of them have a large tolerance of 20 to 50 %or more.

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 10:11AM -0800 On Saturday, November 12, 2016 at 6:50:27 AM UTC-5, Michael Terrell wrote:   > Nazi conspirator, George Soros?   > It is the sheep who sell their soul for a free cell phone and > section eight housing.   That sounds strangely conspiratorial. And, of course, the problem with popular conspiracy theories is that far too many people have to know about it to keep in even a little bit secret, or even dimly lit.   Point being that "begging the question" fallacies usually start with a statement along the lines of "you do know that....".   Followed by the 'false premises' fallacy: "But everyone knows that....".   Usually there is a sprinkling of "ad hominum" in the mix - such as the word Nazi and so forth.   Sorry. But we here in the US are entirely within a "time will tell" situation. We have not had such a polarized election with two such foul candidates since Grant ran against Seymour in 1868. Grant did not rise to the occasion. One hopes that this is not an historical precedent.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Nov 14 10:14AM -0800 https://mail.aol.com/webmail/getPart?uid=33646633&partId=2&scope=STANDARD&saveAs=Trump.jpg     Just an FYI.

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