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N_Cook <diverse@tcp.co.uk>: Nov 17 02:21PM This variant , they've sorted out the bad thermal air path "design" for the main heatsink, but introduced another. Zobel network involving 2x 4.7R 5W in parallel litterally back to back and also hemmed in, touching, by the caps, relay and the copious white gunk. A pathetic looking flat baffle plate that presumably was someone's idea that the inlet air would then magically divert over the tops of these Rs, unlikely. So instead of 10W rating , presumably effectively derated to about 3W. Etiology looks as though PbF failure of one R solder joint (burnt pcb hole in the pcb around the pin ) leading to that R actually cracking up and going o/c and eventually the other one going high, and along the way the heat cooked one of the paralleled caps to short circuit . Also cooked and melted relay case , so the contact is permanently closed, explains the switch on and off thumps/chirps , over a few weeks, that did not used to be there.

N_Cook <diverse@tcp.co.uk>: Nov 17 03:33PM 2 exactly the same size and shape yellow block encased caps, in parallel. Surviving one marked 104K 400V and measures 94nF but the other one marked 33 ,then possibly 4, then the rest is burnt away. So amp , as a combo ,built for a specific speaker fair enough, but would zobel using 330nF instead of 430nF +/- 20% or whatever , be that significant?

etpm@whidbey.com: Nov 16 09:04AM -0800 On Wed, 16 Nov 2016 09:25:37 +0000, Geo <nhhu-o3hu@dea.spamcon.org> wrote:   >the last (bottom) regulator cathode? >I would guess it might be to chassis so "no output" is correct.   >If all three glow then the voltage across each should be fine. There is a connection. It does not go to the chassis. I think the tube is bad. All tubes are gonna be replaced anyway. Eric

etpm@whidbey.com: Nov 16 09:12AM -0800 On Wed, 16 Nov 2016 05:35:40 -0800 (PST), "pfjw@aol.com"   >Sheesh, guys and gals - it is almost as if this were rocket science. It ain't nohow.   >Peter Wieck >Melrose Park, PA That's it, I'm convinced. I'm gonna order the caps from JustRadio. They are the correct rating for voltage and capacitance, different connections-not screws, but big tabs instead. Easily soldered to the bus bars. I have been thinking about those big bus bars and am wondering if the size is either for mechanical reasons or lower resistance reasons. I can't see the original caps dumping enough current to need such robust bars. Especially considering the relay contacts connected to the cap bank and the much lighter wires running from the bus bars and relay to the xmfr. Lemme know if you have all the tubes and I'll send a check. Thanks, Eric

"pfjw@aol.com" <pfjw@aol.com>: Nov 16 09:23AM -0800 On Wednesday, November 16, 2016 at 12:06:15 PM UTC-5, et...@whidbey.com wrote:   Please note the interpolations:   > bus bars. I have been thinking about those big bus bars and am > wondering if the size is either for mechanical reasons or lower > resistance reasons.   Both. Mechanical as this machine moves, vibrates and is subject to various stresses thereby. And, consider that the shop I worked in a _long_ time ago used their welder two 10-hour shifts in a row, about 2 days per week. That is a lot of welds.   Electrical as the enemy of these machines is heat. Heat increases resistance which can throw off settings - and with 0.003 inconel pimple washers the difference between the weld not taking and a burn-through isn't much, and on aircraft and/or nuclear rated parts that is unacceptable.   I can't see the original caps dumping enough > contacts connected to the cap bank and the much lighter wires running > from the bus bars and relay to the xmfr. Lemme know if you have all > the tubes and I'll send a check.   You will have to wait into the weekend for me to get an edgewise to check my stock. Our youngest cat (3 years old, 18 pound Maine Coon mix) has just discovered that he can use the dog door. So, my primary task is to cat-proof the dog yard so he may go outside, but not any further. We may be suburban, but we have foxes, raccoons, other cats and cars to contend with.   As to sending a check, that is not how it works. If I have the tubes, I will send them to you - and then *if* they work out, you may send the check.   Peter Wieck Melrose p

John Robertson <spam@flippers.com>: Nov 16 10:04AM -0800 > There is a connection. It does not go to the chassis. I think the tube > is bad. All tubes are gonna be replaced anyway. > Eric   Keep your old tubes until you can test them and be sure they are bad. These old tubes are not getting any more common! 2D21s were always a bit fussy and were replaced by 2050 tubes not long after they came out...even new out of the box there were failures. Seeburg jukeboxes used 2D21s for their early tormat design and quickly changed the design to 2050s part way through the second year of production due to read-out and write-in issues. I have schematics for 2D21 testers that I can dig up (probably find similar schematics easily enough online) and post of my tech ftp pages if there is a demand/request. The 2D21 is pretty easy to test, if you have access to a good tube tester it will usually show them on the Seldom Used auxiliary tube list. The 2D21s are go/no-go kinda things.   OA2s are also pretty basic tubes. They use a conductive gas to regulate to 150VDC. If the tube is not broken or gassy then it should be just fine. Check the Getter flash in the tube - it should not be showing any white powder, that is a tube that has lost its seal and oxygen has entered...   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 16 10:26AM -0800 On Wednesday, November 16, 2016 at 1:04:24 PM UTC-5, John Robertson wrote:   > fine. Check the Getter flash in the tube - it should not be showing any > white powder, that is a tube that has lost its seal and oxygen has > entered...   2D21s are/were used commonly in dental X-ray and Fluoroscope machines, and when, also back in the day, I was working for a GC doing some serious rebuilding at HUP in Philadelphia, one of the docs needed to resurrect such a machine for historical purposes. I found him the tubes he needed locally, including two 2D21s. This was "Before Internet", so not an instantaneous process.   I also keep a very good tester (Hickok 539B), so no tube would leave this house untested.   Yes, of course, keep any undamaged old tube.   Peter Wieck Melrose Park, PA

Clifford Heath <no.spam@please.net>: Nov 17 08:29AM +1100 > OK!! EVERYBODY!! > Step back a minute and have a look at what is being discussed here: > Sheesh, guys and gals - it is almost as if this were rocket science.   You're responding to Chris' answer to *my* question about how I can make *my* welder do more than it was designed to. I'm thankful to him for that, and I don't think he needs to "step back a minute".

"pfjw@aol.com" <pfjw@aol.com>: Nov 17 07:31AM -0800 On Wednesday, November 16, 2016 at 4:30:36 PM UTC-5, Clifford Heath wrote:   > You're responding to Chris' answer to *my* question about how I > can make *my* welder do more than it was designed to. I'm thankful > to him for that, and I don't think he needs to "step back a minute".   No, I made a generic suggestion that we not over-analyze what is, in actuality, a very simple issue. A discussion about cap-reforming has no place in this particular discussion, nor do photo-flash caps except as a perhaps interesting sidebar. A "you might try this if practical" type thing. And at that level, I agree, one might try it.   This discussion, for the OP in any case, is about restoring a piece of industrial equipment back to reliable and optimal function. Emphatically Not rocket science.   Now, here is the issue with industrial tools with the goal of making it 'do more than it was designed to do'. Well designed tools have a level of resilience already built in. Going beyond those parameters puts the tool, operator and surroundings at-risk either a little bit, or perhaps quite a bit depending on the tool. It is, in every case, under every condition, an exceedingly bad idea. If you choose to put yourself and your property at-risk, that is your privilege - and may you never be in line for a Darwin Award.   I have worked in an industrial production environment with very fast, very powerful, very hot machines, materials and moving parts in close proximity. I would NOT want to think that some lashed-up tool operating outside its design parameters had my life or health dependent upon its smooth operation.   Peter Wieck Melrose Park, PA

Robert Bannon <rbannon@yahoo.spam.nowhere.invalid>: Nov 16 08:48PM On Tue, 15 Nov 2016 13:32:25 +0000, Stormin' Norman wrote:   > http://www.harborfreight.com/125-volt-15-amp-male-plug-93686.html   I need the female more than the male but that price of 3 bucks seems like the best I've seen for a good quality connector.   The females are also 3 bucks so this seems the best bet yet! http://www.harborfreight.com/catalogsearch/result?q=125+volt+15+amp+female+plug+connector

Robert Bannon <rbannon@yahoo.spam.nowhere.invalid>: Nov 16 08:48PM > Product # > HBLHBL5266CA > Just for starters.   Harbor Freight have HFT brand plugs for 3 bucks. http://www.harborfreight.com/125-volt-15-amp-female-plug-connector-61568.html   How is HFT as a company?

"pfjw@aol.com" <pfjw@aol.com>: Nov 16 01:35PM -0800 On Wednesday, November 16, 2016 at 3:48:30 PM UTC-5, Robert Bannon wrote:   > Harbor Freight have HFT brand plugs for 3 bucks. > http://www.harborfreight.com/125-volt-15-amp-female-plug-connector-61568.html   > How is HFT as a company?   It is not so much how HFT (H-arbor F-reigh-T) might be, it is the brute fact that Harbor Freight is mostly an outlet for Chinese Junque, and _ANYTHING_ from that source is suspect. I find Harbor Freight a very dangerous organization, as many of the tools they sell go from "new" to dangerous almost in a flash, with special attention to moving parts and anything gasoline driven or electrical. A neighbor purchased a 4,000 watt generator from them last spring for his truck - he is a high-end handyman. He reported that it blew up in less than 20 hours. HF took it back, but he then spent the money and purchased a small Generac unit. No more troubles.   Peter Wieck Melrose Park, PA

Stormin' Norman <norman@schwarzkopf.invalid>: Nov 16 10:57PM >the best I've seen for a good quality connector.   >The females are also 3 bucks so this seems the best bet yet! >http://www.harborfreight.com/catalogsearch/result?q=125+volt+15+amp+female+plug+connector   I have used quite a few of them and I have never experienced a failure.

clare@snyder.on.ca: Nov 16 08:52PM -0500 On Wed, 16 Nov 2016 20:48:28 -0000 (UTC), Robert Bannon   >Harbor Freight have HFT brand plugs for 3 bucks. >http://www.harborfreight.com/125-volt-15-amp-female-plug-connector-61568.html   >How is HFT as a company? Generally speaking they ar a purveyor of "middle of the road" Chiunese junk.. Likely adequate for your use but certainly not "hospital grade" quality.

clare@snyder.on.ca: Nov 16 08:57PM -0500 On Wed, 16 Nov 2016 20:48:29 -0000 (UTC), Robert Bannon >the best I've seen for a good quality connector.   >The females are also 3 bucks so this seems the best bet yet! >http://www.harborfreight.com/catalogsearch/result?q=125+volt+15+amp+female+plug+connector They "look like" a quality connector - but check them There is a reason they are 1/4 or less of the price of a brand name part. They MAY be "good enough"

micky <NONONOmisc07@bigfoot.com>: Nov 17 12:30AM -0500 In sci.electronics.repair, on Wed, 16 Nov 2016 13:35:07 -0800 (PST), >> http://www.harborfreight.com/125-volt-15-amp-female-plug-connector-61568.html   >> How is HFT as a company?   >It is not so much how HFT (H-arbor F-reigh-T) might be, it is the brute fact that Harbor Freight is mostly an outlet for Chinese Junque, and _ANYTHING_ from that source is suspect.   This is not fair. I had my appendix out at Harbor Freight Hospital and they did a real good job. Cute nurses too.   Wait. It was Harbor View Hospital. Sorry about that. That was a real hospital in Batlimore until they sold the naming rights to Medstar, maybe because too many people confused them with Harbor Freight. http://us.hospitalby.com/usa-hospital/harborview-9-hospital/ And I still have my appendix.

hgao14@gmail.com: Nov 16 01:10PM -0800

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