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"pfjw@aol.com" <peterwieck33@gmail.com>: Dec 19 10:14AM -0800 On Wednesday, December 19, 2018 at 10:45:45 AM UTC-5, tabb...@gmail.com wrote: There was good reason in the choke setup rather than just using a bigger cap.   Some historical perspective from this side of the pond, where 300,000,000 "valve" radios were manufactured from about 1913 to about 1963.   a) Low-cost, permanent-magnet speakers did not become common or reliable until well into the 1940s, and much of that was driven by war-time research. Sure, small speakers for portable radios were common, but larger speakers designed for severals-of-watts of power, not so much. And big, honking speakers such as were on large consoles, even less so.   b) Making the choke a (costly) necessity to provide a magnet for the speaker. Not a convenience. And, with that in mind, many manufacturers then cut back on the size of the transformers to save costs. Leading to the limitations on capacitance - which protects both the choke (limiting B+) and the transformer (current). Some AC/DC radios used half-wave rectifiers for their voltage-dropping properties.   c) One may, pretty much, used as much capacitance as one wishes _AS LONG AS_ the B+ remains withing spec. And this can be a close-run thing. Note that in the days of potted paper caps, some of the earlier consumer radio manufacturers such as Atwater-Kent were quite specific in their service literature that capacitance values were NOT to be exceeded, again referring to B+ voltages, not rectifier or transformer overloads. And, as it happened, these radios tended to have very large chokes, weighing several pounds in copper alone.   c) When repairing (vs. a museum-quality restoration), you have options not available to the OEM, as well as knowledge and materials unknown to them back when all this stuff was "New". What this means is that you may, without sin, make upgrades or make repairs based on present-day technology to replace compromised elements of/within the original item. The only valid endorsement of what is or is not 'good practice' is whether the radio functions properly, safely and without danger to its users into the foreseeable future. That it uses as many as is safe and practical of the original elements is a good thing. But, if it does that by means of compromising its safe and continuing use, to that extent, it is a failure.   There are sources for field-coil speakers. There are those that will rebuild existing field-coil speakers. If that level of restoration is your goal, go for it. Whatever else, enjoy it!   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Dec 19 11:38AM -0800 > There are sources for field-coil speakers. There are those that will rebuild existing field-coil speakers. If that level of restoration is your goal, go for it. Whatever else, enjoy it!   > Peter Wieck > Melrose Park, PA     A couple of points to pick up on there. If you look at valve rectifiers, they come with specs on max C. This should not be exceeded. There is good reason for that.   And no, it is not good practice to re-engineer antique radios without even having a reason. Not a bit. If you want modern junk there's plenty about, go buy it. Too much historic stuff is ruined & destroyed by people with insufficient clue what they're doing.     NT

tabbypurr@gmail.com: Dec 19 11:39AM -0800 On Wednesday, 19 December 2018 19:38:41 UTC, tabby wrote:   > A couple of points to pick up on there. If you look at valve rectifiers, they come with specs on max C. This should not be exceeded. There is good reason for that.   > And no, it is not good practice to re-engineer antique radios without even having a reason. Not a bit. If you want modern junk there's plenty about, go buy it. Too much historic stuff is ruined & destroyed by people with insufficient clue what they're doing.   > NT   I've just realised it's you again. You'll never see sense so I won't bother continuing.     NT

Ralph Mowery <rmowery28146@earthlink.net>: Dec 19 06:09PM -0500 In article <c7a86686-2882-4c65-8bfe-c5ad4a6e1ecd@googlegroups.com>, tabbypurr@gmail.com says...   > A couple of points to pick up on there. If you look at valve rectifiers, they come with specs on max C. This should not be exceeded. There is good reason for that.   Yes, the tube rectifiers do have a maximum filter capacitor value. Adding much more capacitance will not raise the voltage in most cases. It is the excessive current that is hard on the rectifier tube as the capacitor charges and discharges during each cycle.

tabbypurr@gmail.com: Dec 19 05:12PM -0800 On Wednesday, 19 December 2018 23:09:37 UTC, Ralph Mowery wrote: > Adding much more capacitance will not raise the voltage in most cases. > It is the excessive current that is hard on the rectifier tube as the > capacitor charges and discharges during each cycle.   mean i is the same, but peak i is higher & conduction angle narrower.     NT

John Robertson <spam@flippers.com>: Dec 19 05:20PM -0800 On 2018/12/19 3:09 PM, Ralph Mowery wrote: > Adding much more capacitance will not raise the voltage in most cases. > It is the excessive current that is hard on the rectifier tube as the > capacitor charges and discharges during each cycle.   An example - the 5U4GB (RCA) is recommended to have no more than 40UFD on the Input To Filter. The note on this value says:   "Higher values of capacitance than indicated may be used, but the effective plate-supply impedance may have to be increased to prevent exceeding the maximum value for peak plate current."   From the RCA Receiving Tube Manual - RC-30 - 1975.   I have a nice assortment of tech books on tubes as we fix tube amps regularly for jukeboxes.   Hmm, tube amps...I wonder if we should install them in pinball games...that would be a hoot!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

tabbypurr@gmail.com: Dec 19 05:31PM -0800 On Thursday, 20 December 2018 01:20:57 UTC, John Robertson wrote:   > Hmm, tube amps...I wonder if we should install them in pinball > games...that would be a hoot!   > John :-#)#   My 1924 set has all of a few 2uF paper caps on the supply line. They cheated though - it's for dc mains. I've seen rather less than 40uF on some ac mains sets.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Dec 20 07:38AM -0800 On Wednesday, December 19, 2018 at 6:09:37 PM UTC-5, Ralph Mowery wrote:   > It is the excessive current that is hard on the rectifier tube as the > capacitor charges and discharges during each cycle.   Only in direct relationship to the actual load. Assume the cap is sized precisely to the anticipated maximum load - then, theoretically, it should discharge 100% and recharge 100% on each cycle.   Assume that the cap is sized to 100% more than the anticipated load - then, theoretically, it will discharge to 50% and recharge to 100% on each cycle.   Also assuming that the power-supply is capable of delivering the full load + some additional amount of current.   Overloading the transformer will occur if the load increases due to the additional capacitance. If it remains the same, not so much.   The analogy is a number of individual cells in parallel. The amount of current they can deliver increases. But a 5 watt lamp will remain a 5 watt lamp, no matter what *could be* delivered. And that DC motor will not spin any faster if it is fed its design voltage and amps. What is a capacitor other than an ultra-fast battery? All sorts of (usually bad) things happen when the voltage increases, however. And that is why, by specific reference, the likes of Atwater Kent warned against excessive capacitance in their mains-driven radios - mostly with potted paper caps of 2-or-less uF.   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: Dec 20 11:33AM -0500 In article <e8bde4d2-1688-4a32-9f80-48d903167743@googlegroups.com>, peterwieck33@gmail.com says...   > Only in direct relationship to the actual load. Assume the cap is sized precisely to the anticipated maximum load - then, theoretically, it should discharge 100% and recharge 100% on each cycle.   > Assume that the cap is sized to 100% more than the anticipated load - then, theoretically, it will discharge to 50% and recharge to 100% on each cycle.   This is one of he dumbest statements I have ever heard about how a capacitor works in a power supply. In the normal tube or simple diode supply the capacitor never discharges anywhere near 100 %   As a capacitor discharges to any percentage and then recharges, the ammount of capacitance determins how much peak current will be drawn from the transformer and through the rectifier. That is what is hard on the rectifier tubes and why they sp;ecify a certain maximum capacitance.

John-Del <ohger1s@gmail.com>: Dec 19 08:49AM -0800 > actually finishes a part. So whatever new control I put on must have > this feature. It is very convenient and saves lots of time. > Eric   If the hybrid is potted in epoxy then I don't see any way of getting lucky. Any attempt at depotting epoxy will likely add to it's problems.   If it's potted in a soft silicone snot or not potted at all, you might be able to spot something. If you need to do any soldering you MUST preheat the crap out of it as the ceramic substrate will steal heat like an Amazon porch pirate doing his Christmas shopping.

Jeff Liebermann <jeffl@cruzio.com>: Dec 19 09:55AM -0800 >The reason I wondered about the hybrid is not to fix it but to find >out what it does so that I can figure out how to test it. The same >board keeps failing in the control and I don't know why.   Third try: If you want specific information, models and numbers are needed. You get zero points for being as vague as possible.   Any particular board in the Fanuc 3T that is failing? Do you have the Fanuc 3T maintenance manual? With a schematic, you can probably guess what the A-RV06 hybrid does for a living by looking at the input/output pin labels. Ah, found the manual: <http://cncmanual.com/download/1647/> 24.5MBytes Ugh. Not much in the way of schematics and no mention of A-RV06.   At one point, we were blowing up servo amplifier boards and modules. By chance, I put my clamp ammeter around the drive lines and found that the common mode current was not zero. I scope later showed some rather large spikes. What had happened was that the frame and case grounding had gone intermittent because the screws had rattled loose. A little oil and rust in the under the ground lugs, and fairly soon there was no connection. I couldn't see it with a continuity tester so I systematically cleaned and tightened every ground frame screw that I could find. It worked.   >count is also restarted. The counter only counts when the program >actually finishes a part. So whatever new control I put on must have >this feature. It is very convenient and saves lots of time.   M54 for Fanuc, M30 for most others. A quick skim of the Chinese mill controller manual shows M30 is supported, but not M54. Also, I was thinking of the spindle turns counter in the lathe version of the Chinese controller that is useful for cutting threads. Sorry for the confusion.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

etpm@whidbey.com: Dec 19 11:24AM -0800 On Wed, 19 Dec 2018 09:55:06 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >thinking of the spindle turns counter in the lathe version of the >Chinese controller that is useful for cutting threads. Sorry for the >confusion. Boy Jeff, I am totally not trying to be vague. I was looking for just generic help but really should have provided as much info as possible. Especially since there are all sorts of hybrid ICs and they can even be on regular circuit board substrates, from what I have seen. So, to be specific and complete, which I should have been doing all along, here is the info: The board is the A20B-0008-0630/02A. It is also known as PC1 for this control, the 3T. The board handles the I/O from and to the machine. I do have all the generic 3T manuals from Fanuc as well as the manuals from Miyano. All the wiring manuals available. They do not show any circuit board specifics, just where wires and connectors go. The first time this board failed, a couple years ago, the machine had various alarms that said a certain switch was open. I forget exactly which switch. But it was for a door or cover. Anyway, my machine does not have this switch. Yet the board thought that it was open. Just to make sure I traced the pins on the board connector to the cable connector and added all the optional switches. Every switch would show its state in the diagnostic screen. and all would change a bit when on or off except for the switch that was supposedly causing the alarm. Replacing the board fixed the problem. Just recently I posted about a parameter changing and how changing it back made the machine work properly. I was being hasty. The fix lasted one part. The machine went back to ignoring programmed speed commands and the signal to the part counter went away. The changed parameter did not change again though. Fanuc thought that the PC1 board might again be the problem so I bought a used one and the machine works properly again. Fanuc thought the board might be the problem because it handles the I/O and because the control thought that it was executing the M25 code. The start light flashed and the machine didn't hang up as it would if the control didn't get a FIN signal after executing an M code. And even though the speed signal to the spindle drive comes off of the main control board, the speed control dial and all the switches all go throug the PC1 board. Thanks, Eric

Jon Elson <elson@pico-systems.com>: Dec 19 04:36PM -0600 On Tue, 18 Dec 2018 14:09:12 -0800, etpm wrote:   > has a turret, tailstock, and counter that would need some sort of PLC > programming to interface with the control. I might need to learn ladder > programming again. LinuxCNC contains a real-time version of Classic Ladder, a ladder logic implemented in software, that can be interconnected with other components in the motion and G-code interpreting sections. This is great for tool turrets and similar systems.   > The problem with changing the control is that I need enough time > when the machine is not needed to make the swap. Yes, certainly the classic conundrum! But, once you do it, you will be greatly relieved to know that the system is 100 X more reliable, and you can fix anything that goes wrong with modern and affordable parts.   Jon

Jon Elson <elson@pico-systems.com>: Dec 19 04:40PM -0600 On Wed, 19 Dec 2018 08:28:08 -0800, etpm wrote:   > restarted. The counter only counts when the program actually finishes a > part. So whatever new control I put on must have this feature. It is > very convenient and saves lots of time. I'm pretty sure somebody did this about a year ago in LinuxCNC. It should be pretty trivial to implement this even in the G-code, with the entire program in a do while loop, and the counter as a numbered variable. You could also display the counter value on the virtual control panel.   Jon

etpm@whidbey.com: Dec 19 04:43PM -0800 On Wed, 19 Dec 2018 16:36:06 -0600, Jon Elson <elson@pico-systems.com> wrote:   >greatly relieved to know that the system is 100 X more reliable, and you >can fix anything that goes wrong with modern and affordable parts.   >Jon I appreciate your posts Jon. I have been looking at LinuxCNC as has my son. In an effort to convince me to upgrade the control. You said: "I'm pretty sure somebody did this about a year ago in LinuxCNC. It should be pretty trivial to implement this even in the G-code, with the entire program in a do while loop, and the counter as a numbered variable. You could also display the counter value on the virtual control panel." I don't know what a do while loop is. I'm sure it's easy enough to find out though. As long as the programming doesn't change I don't really care. I mean, as long as all my old programs will work the same without needing any changes. Having the count displayed on the main display is fine but it would be best if the original counter operated the way it does now. That is, a number is entered via the thumbwheels on the counter and then when the displayed count reaches that number the counter sends a signal to the machine and it stops. Because the counter is not involved in the programming, except that it is incremented by an M code, the count can be changed while a part is running. Which I have done more than once. If I was able to read the ladder programming in the eproms that control the machine would I just be able to cut and paste it into the LinuxCNC software? Man, would that make life easy. If a breakout board can be made to act just like the existing boards then maybe the control will be pretty close to plug and play. Can it really be that easy? Eric

Jeff Liebermann <jeffl@cruzio.com>: Dec 19 09:53PM -0800 On Wed, 19 Dec 2018 16:40:14 -0600, Jon Elson <elson@pico-systems.com> wrote:   >entire program in a do while loop, and the counter as a numbered variable. >You could also display the counter value on the virtual control panel. >Jon   This might help with the parts counter function:   "Parts counter M code?" <https://www.practicalmachinist.com/vb/cnc-machining/parts-counter-m-code-290803/>   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Diesel <me@privacy.net>: Dec 19 09:41PM "David B." <"David B"@nomail.afraid.org> news:J3cSD.370640$7P5.35300@fx19.fr7 Tue, 18 Dec 2018 19:41:25 GMT in alt.computer.workshop, wrote:   >> []'s   > It's now apparent that he and I are already part of the body of > Christ.   Along with the priests who can't keep their hands off the private parts of small children entrusted in their care? Or, are you speaking of another body of Christ? > When was the malware removed from the destination of that link, > Shadow?   When was malware ever present via that link, David? As you full well know, Securi hit on a false positive and has since corrected it. At no time (And you know this, it was explained the first time you tried to distract people from the site contents with totally made up slime about the site and/or it's administrator) was the site ever infected with anything or capable of infecting any visitors with anything.   This was explained like I said, ad nausem the first time you tried to besmirch the site in an effort to try and discredit it. You failed to do so because anyone who's interacted with you over time previously already knows by experience with you that the contents of the site is accurate to the letter concerning you. Stalking is what you do. It's what you've done for years, and, I've little doubt you'll continue to do it until the police visit you (again) and explain (again) that what you're doing isn't okay, is infact illegal in some parts of the world, and you should stop doing it. It's just the gun thing all over again for you.   Btw, about that gun. You made it a point on several occasions to tell the usenet audience at large that you had special permission and paperwork that goes along with it to have it. Why, when the cops visited you didn't they know about this paperwork? Why did you have no firearm to show them? They came to see you (after months of you ducking their attempts to make contact with you; yes, you remember telling us about your concerns that 'fake' police were trying to reach you? :) They were trying to reach you because of your posted threat of using a firearm towards another posters children, on your boat. You tried to back peddle and do some serious damage control when, basically, everybody picked up on your veiled threat and called you out on it. Wasn't a good enough cover thy ass job though, because the police considered it serious enough to warrant multiple communications attempts as well as an in person visit when they finally could reach you.   You intentionally ignored them while out on the sewage canals though and kept usenet uptodate with your 'concerns'. Do you remember any of this David? Or, has the alcohol gone ahead and pickled that area of your long term memory?   I'll remind you, again:   You told many of us on usenet in various newsgroups that you not only had a handgun, but also had the necessary paperwork to be in possession of it. Yet, the police recovered no firearm and told the victim you claimed not to have one. And, they couldn't find any valid paperwork stating that you had permission to have one.   Were you lying to the cops or us David? At some point, it's obvious you lied about the gun. The only question is, who did you lie to about the gun? The police, or us? If you lied to the police about it, then it's clear you lied to us about having the necessary paperwork. Either way you slice it, David, you lied at some point about the gun. You may have lied to both parties, infact. One, you have the gun, but it's not legal so you couldn't let the police know you had it. So you lied to us about having permission to 0wn one in your home. Or, you really don't have a gun, and, lied to us all when you stated that you did as well as have permission to be in possession of it, due to your previous military service.   Again, either way, you lied your ass off at various points along the way. So much for that 'good guy' facade you try so hard to convince people you are. You just continue to forget this important little detail: You have an established reputation as a lying, scumbag, stalking troll of the worst kind. I just don't see how you could possibly go about fixing it when you continually lie as often as you do.   It's really bad when you consider how easy it is to prove you're lying. You don't even put forth real effort into it. You insult others intelligence with your facade 'investigator' claims. You have no training, no license, nothing of the sort. You *are* a stalker, not an nvestigator. And, I don't think your investigator rouse is going to keep you out of trouble for an indefinate period of time.   Speaking of some of the lies you've told, you also recently admitted to considering filing a known false counter notice to a DMCA notification you got served. You know full well that fair use doesn't cover what you were doing and never did. You also know that the counter notice cannot be filed out by you and be completely honest and legal as you do so.   At no time were you given permission, and, on more than one occasion you've been specifically made aware of the fact you do NOT have permission to host my things elsewhere, in public you've been told this on more than one occasion. I have succesful previous dmca notices which were upheld against you for the very same thing you recently abused wordpress, imgur, and vimeo terms of service to host video and images that you knew, first hand, prior to uploading either that you didn't have permission to do so and were infact, knowingly committing copyright infringement for the purposes of stalking and blackmail.   It's worth more to me from a 'boo ya' point of view than the dmca notices i've got you with in the time I've had the misfortune of knowing of your sorry existance.   You have until this weekend before I make my next move, that, I guarantee you, isn't going to be fun for you. :-) I promise that if you think you regret having met me now, you'll really be kicking yourself in the ass for not negotiating a cease fire when you had the chance. When i'm done firing on your zone, they'll be nothing left but craters.   I sincerely hope you think I'm bluffing and do absolutely nothing with the clear evidence all over your blog that supports my complaint. Along with email correspondence I retained between myself, google, youtube, vimeo and imgur (You've got several valid dmcas against you with imgur, I'm sure you know that already though), I've got you dead to rights this time around, and this time, David, I'mnot going to let you go to rejoin the swarm. This time, you're coming onboard to be processed into food.   -- Don't become the next David Brooks cyberstalking victim! Visit https://tekrider.net/pages/david-brooks-stalker.php (10/10 WOT) to learn more. If you've already become a victim or know someone who has, you can provide the following information to them, your lawyer, local law enforcement, etc. https://www.devon-cornwall.police.uk - His local police. Report? David Brooks (BoaterDave) Jersey Cottage 86 Granary Lane Budleigh Salterton Devon EX9 6ER United Kingdom Phone: 44-1395-443340 (H) 07974-193550 (M) Email(s): davidandtrishab@btinternet.com, boaterdavetj@aol.com

"David B." <"David B"@nomail.afraid.org>: Dec 19 10:10PM On 19/12/2018 21:41, Diesel (Dustin Cook) threatens David B.   > got you dead to rights this time around, and this time, David, I'm not > going to let you go to rejoin the swarm. This time, you're coming > onboard to be processed into food.   You once told me that you don't MAKE threats, Dustin.   Shall I add this one to my Blog?   One small point about taking down items. Can you remove them from an 'alt' Usenet newsgroup, where I've already put them for safe keeping?   -- Regards, David B.   https://vxer.home.blog/2018/12/08/vxer-a-profile/

"David B." <"David B"@nomail.afraid.org>: Dec 19 10:32PM On 19/12/2018 10:53, Shadow wrote:   >> Phil might >> be interested to view this finding too:-   > Message-ID: <vGx6B.191110$rM3.164669@fx17.fr7>   The website details found in the Source Code of the Tekrider site, when followed, go to a website which, when submitted to Virus total show that said site *IS* infected.   https://www.virustotal.com/#/url/42cbd72a208a75cd3526fc7fce3e3b4d7ddac2c55a78694434ad69416d2992ad/detection   Co-incidence? I don't know.   Final URL http://detail-cc.cc/check_availability.php?s=windows-web-browsers Serving IP Address 199.59.242.151 Status Code 200 Body Length 3.84 KB Body SHA-256 f7853b4ad6d9a012677e6a492443a13152e1733ff5ec601caac634367edcdc11 Headers connection: keep-alive content-type: text/html; charset=UTF-8 date: Wed, 19 Dec 2018 22:24:13 GMT server: openresty transfer-encoding: chunked x-adblock-key: MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANDrp2lz7AOmADaN8tA50LsWcjLFyQFcb/P2Txc58oYOeILb3vBw7J6f4pamkAQVSQuqYsKx3YzdUHCvb   -- Regards, David B.

John-Del <ohger1s@gmail.com>: Dec 19 01:12PM -0800 > got a monitor chassis with a bad ka3842. i have a tl3842, but am not well versed enough to compare via datasheets. can i do the substitution?   > thanks   Not telling you what to do (and I didn't go through every parameter), but they're close enough where I'd try it.   I might disconnect the output to make sure it doesn't cause an over volt in case the feedback is different.

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