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hankvc@blackhole.lostwells.org (Hank): Nov 12 05:53PM In article <olnf0dpr1a0sr2r4c92040jh4j5sst9a5o@4ax.com>,   >The old one is reading 9.73 NF with my meter, so that is close to the >correct amount. (Of course there is no voltage on it, so it make >breakdown when voltage is applied).   Well, since you're the "expert" on restoring old radios, do you really need to be told how to restore a run-of-the mill AA5?   First off, a 10,000 pf Micamold is a paper cap, not a mica. Most AA5's had a .01 or .02 400 or 600 volt cap between the output tube plate and ground. Some hooked it across the output transformer terminals or to the output tube cathode if the output tube cathode resistor had a bypass cap. Very common failure point, and a common "quick fix" was to dike the cap loose, though it should be replaced. There's a reason why AA5 builders included it. You want at least a 600 volt cap there. A .01 or .02 mike 1000 volt disk ceramic between the 50B5 plate and ground is a good fix.   Restoration of an AA5 should include replacement of the input coupling cap to G1 of the output tube (typically 5000 pf), and a check that the ouput tube grid leak and cathode bias resistor (typically 470K and 150 ohms) are correct. Your choice whether to put a (typically) 20 mfd. bypass cap across the cathode bias resistor and/or to replace the bias resistor with 150 or 180 ohms.   Hank

Foxs Mercantile <jdangus@att.net>: Nov 12 02:46PM -0600 On 11/12/2017 2:38 AM, Frank wrote: > Seems likely your capacitor was clipped out by > an experienced serviceman a few decades ago.   Any "technician" that would clip a part, and leave it hanging, rather than replace it is NOT an experienced serviceman. He's a hack.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

tabbypurr@gmail.com: Nov 12 03:39PM -0800 On Sunday, 12 November 2017 20:46:11 UTC, Foxs Mercantile wrote:   > Any "technician" that would clip a part, and > leave it hanging, rather than replace it is NOT > an experienced serviceman. He's a hack.   Well... there's no lack of consumer products with parts missing, demonstrating that - in some cases the initial extra parts aren't really needed - in others more than one version exists or was planned   It's like cars, surprising how many bits you can remove and it still works.     NT

oldschool@tubes.com: Nov 13 12:21AM -0600 On Sun, 12 Nov 2017 17:53:27 -0000 (UTC), hankvc@blackhole.lostwells.org (Hank) wrote:   >>breakdown when voltage is applied).   >Well, since you're the "expert" on restoring old radios, do you really >need to be told how to restore a run-of-the mill AA5?   I dont recall saying that. Maybe you need a reading comprehension course.     >First off, a 10,000 pf Micamold is a paper cap, not a mica. Most AA5's   That's deceiving. It's called a MICAmold. That would tell me that it's a MICA cap.   But yea, I know that was a time when there was a lot of confusion between manufacturers of caps and some other components. I have a graphic image showing all the possible color codes for those domino caps. Each manufacturer had a different dot layout. (At least the colors matched the resistor code for numbers). But I saved that picture so I can look them up. Unlike most other parts, there is no simularity between brands and I actually have not run across all that many of them. I surely did not know they made paper caps in that style.   I sure am glad they pretty much standardized those parts by the late 50s or early 60s.   This particular radio has almost every type of cap that was made in those days. It's almost like they were using up whatever was on hand.   >builders included it. You want at least a 600 volt cap there. A .01 or >.02 mike 1000 volt disk ceramic between the 50B5 plate and ground is a >good fix.   I'll likely use a ceramic disk for that one. I am curiuous, since the radio likely works without that cap, what is the real purpose for it? >bypass cap across the cathode bias resistor and/or to replace the bias >resistor with 150 or 180 ohms.   >Hank   On this particular radio, I intend to replace all the caps. There are some very nasty looking caps in it. There is a 0.1 tubular cap across the power cord to the chassis that is literally melted. The ends are oozing out, and it's not wax, its some sort of hard plastic or (whatever it is). If it was not one of the nicest looking radios I have ever seen, I would not even fix it. I love the horse on top. As soon as I saw this, I had to buy it, even though it was in very poor shape.   By the way, I dont usually find bad speakers in these old radios, but this one is torn, and was already glued. It's listed as a 3.5 inch. I dont have a junked radio to get it from. Where do you guys buy replacement speakers for these antique radios?

oldschool@tubes.com: Nov 12 11:54PM -0600 If you collect radios and have more than 10 radios, this is the solution:   http://78.media.tumblr.com/971e9154425b73a47b8e28ede4a2fb60/tumblr_inline_mrnnt99phm1qz4rgp.png   (Now you can listen to ALL of them at once) !!! :)

bruce2bowser@gmail.com: Nov 12 09:36PM -0800 mode? On Wednesday, November 1, 2017 9:39PM, tschw...@gmail.com wrote: NT: > and yes they seem silly in many cases. Manufacturers feel pressured > to display that "Energy Star" logo.... but it does add cost and complexity, > and does not generally contribute to reliability.   How can you tell if these logos are genuine or not?

piglet <erichpwagner@hotmail.com>: Nov 12 04:59PM > What is the color code for a -10 ohm resistor. > That's a NEGATIVE 10 ohm resistor, not a standard (positive) 10 ohm > brown-black-black resistor. (Thats 10 ohms below zero ohms).   Just buy one please and tell us all.   piglet

Mike Coon <gravity@mjcoon.plus.com>: Nov 12 05:23PM In article <9c349087-7ae9-4770-8e74-24c02cef456d@googlegroups.com>, luismartino76@gmail.com says... > > brown-black-black resistor. (Thats 10 ohms below zero ohms).   > Come on...   > You can?t have a negative resistor. It?s physically impossible.   But you can. It was mentioned only a day or two ago in the thread on neon indicator bulbs. It is incrementally negative, mind, not averaging across the whole voltage space. And therefore called resistance rather than resistor.   Also applies to the tunnel diodes I used to play with in the 1960s which could be made to oscillate at GHz with hardly any other components.   Mike.

Michael A Terrell <mike.terrell@earthlink.net>: Nov 12 02:42PM -0500 Mike Coon wrote: > than resistor.   > Also applies to the tunnel diodes I used to play with in the 1960s which > could be made to oscillate at GHz with hardly any other components.     He doesn't know the seceret handshake, so none of the cool things aren't available to him.

John Robertson <spam@flippers.com>: Nov 12 01:24PM -0800 > What is the color code for a -10 ohm resistor. > That's a NEGATIVE 10 ohm resistor, not a standard (positive) 10 ohm > brown-black-black resistor. (Thats 10 ohms below zero ohms).   Isn't negative resistance a battery? After all one can measure the ESR of batteries...   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."

rickman <gnuarm@gmail.com>: Nov 12 04:44PM -0500 John Robertson wrote on 11/12/2017 4:24 PM: >> brown-black-black resistor. (Thats 10 ohms below zero ohms).   > Isn't negative resistance a battery? After all one can measure the ESR of > batteries...   That's still a positive resistance just like a resistor you add to the circuit. The only negative resistance I know of is in certain semiconductor devices and only applies over a limited range of voltage and current.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

krw@notreal.com: Nov 12 06:37PM -0500 On Sun, 12 Nov 2017 16:59:40 +0000, piglet <erichpwagner@hotmail.com> wrote:   >> That's a NEGATIVE 10 ohm resistor, not a standard (positive) 10 ohm >> brown-black-black resistor. (Thats 10 ohms below zero ohms).   >Just buy one please and tell us all.   Best Answer!!

lsmartino <luismartino76@gmail.com>: Nov 12 03:40PM -0800 > >> brown-black-black resistor. (Thats 10 ohms below zero ohms).   > >Just buy one please and tell us all.   > Best Answer!!   Indeed!

krw@notreal.com: Nov 12 06:41PM -0500 >That's still a positive resistance just like a resistor you add to the >circuit. The only negative resistance I know of is in certain semiconductor >devices and only applies over a limited range of voltage and current.   That would only be a negative incremental resistance. A negative resistor can't be a passive device. Power has to be added to get a true negative resistance. Line amplifier are an example of negative resistors.

"pfjw@aol.com" <pfjw@aol.com>: Nov 12 05:19PM -0800 Wholey (and entirely) SH*T!!   Negative Resistor:   One (any) resistor in parallel with any other resistor - the net is less than either. That, ladies and gentlemen, and children of all ages, would be a 'negative' resistor. Full stop.   Peter Wieck Melrose Park, PA

Mike Coon <gravity@mjcoon.plus.com>: Nov 12 05:25PM In article <pUZNB.3887$%K.239@fx22.iad>, mike.terrell@earthlink.net says...   > Is there any law of Physics, that Acme can't break? :)   That's probably the deepest philosophical question that's ever been asked on this NG!   Mike.

John-Del <ohger1s@gmail.com>: Nov 12 10:44AM -0800 On Sunday, November 12, 2017 at 10:36:56 AM UTC-5, Michael Terrell wrote:   > > https://www.rollerskishop.com/   > Is there any law of Physics, that Acme can't break? :)       ACME products are grossly over-rated. I once ordered the Acme Wildcat and the damned thing mauled me instead of the person I directly aimed it at.

John Larkin <jjlarkin@highlandtechnology.com>: Nov 12 10:53AM -0800 On Sat, 11 Nov 2017 11:12:00 -0500, Phil Hobbs   >https://www.rollerskishop.com/   >Cheers   >Phil Hobbs   Falling on snow is pretty benign and often fun. Snow is soft and the coefficient of friction is low. Falling onto dirt and rocks and pavement might not be as fun.     --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Michael A Terrell <mike.terrell@earthlink.net>: Nov 12 02:40PM -0500 John-Del wrote:   >> Is there any law of Physics, that Acme can't break? :)   > ACME products are grossly over-rated. I once ordered the Acme Wildcat and the damned thing mauled me instead of the person I directly aimed it at.   Did you specify the victim, when you ordered it? If not, it goes for the fool who opens the package. :)

Clifford Heath <no.spam@please.net>: Nov 13 08:40AM +1100 On 12/11/17 03:12, Phil Hobbs wrote:   > On the plus side, you can get roller skis now. Instant water available > soon.   > https://www.rollerskishop.com/   Skikes are a much better option for most people. Many rollerskis don't have brakes, or only have brakes on one ski. Skikes are like roller skis but they have larger pneumatic tyres, brakes on both, and they work with normal shoes. That makes it easier to keep your skin attached.   Clifford Heath.

Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com>: Nov 12 03:25PM -0700 On Sun, 12 Nov 2017 10:53:08 -0800, John Larkin <jjlarkin@highlandtechnology.com> wrote:     [snip]   >Falling on snow is pretty benign and often fun. Snow is soft and the >coefficient of friction is low. Falling onto dirt and rocks and >pavement might not be as fun.   I have an 11-year-old grandson who is, for all intents and purposes, _pro_ level at ice _and_ roller-blade hockey (*) He takes some might nasty falls (he is, as you might expect, somewhat combative ;-), but he's padded every which way from Sunday.   (*) He is the go-to-guy for the _whole_ league when a substitute player is needed.   He's the first "jock" that I know of in the family history. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | STV, Queen Creek, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | It's what you learn, after you know it all, that counts.

bitrex <bitrex@de.lete.earthlink.net>: Nov 12 06:01PM -0500 On 11/10/2017 03:57 PM, Michael A Terrell wrote:   >    No surprise at all, since I worked in a radio & TV shop at the time. > DIY types would see ads for them, and bug the shop to buy one for them, > even after telling them that it only looked for open filaments.   Not an entirely useless function; probably not all metal tubes get warm under normal operation. Certainly not all glass tubes do; there are a fair number of glass tubes whose filaments don't even get hot enough to glow visibly. Probably in the 1960s not everyone could afford a VTVM or a bench supply that also had a current meter, and the filament resistance might be too high to trigger some simple basic continuity testers

John Larkin <jjlarkin@highlandtechnology.com>: Nov 12 03:01PM -0800 On Sun, 12 Nov 2017 15:25:13 -0700, Jim Thompson >player is needed.   >He's the first "jock" that I know of in the family history.   > ...Jim Thompson     Here is yours truly attempting 360's in the features park at Sugar Bowl:   https://www.dropbox.com/s/u8tgnyedl2r94tu/crash360b.mp4?raw=1   Well, it's hard to hold a camera and spin at the same time.   I'm about as close to a jock that my family had created up to then (not very close) but The Brat is a real athelete. I can still out-ski her just because I'm crazier than she is.   Sanity is over-rated.           --   John Larkin Highland Technology, Inc   lunatic fringe electronics

krw@notreal.com: Nov 12 06:11PM -0500 On Sun, 12 Nov 2017 10:36:52 -0500, Michael A Terrell >> soon.   >> https://www.rollerskishop.com/   > Is there any law of Physics, that Acme can't break? :)   That coyotes actually eat roadrunners?

frank <frank@invalid.net>: Nov 12 10:04PM > traces inside the PSU, rendering the printer inoperable at least. The way > the PSU was designed allowed for the cap to be damaged without causing a > fire risk or destroying the PSU.   Well, not quite. The capacitor still burned completely, the PCB was mostly carbonized under both the capacitor and the resistor. The resistor measures now 1k5 ohms, I don't know what was its initial value, but it could only limit the current and burn itself too. Not too clever as a fuse. If I'd expect an X2 rated capacitor to catch fire, I'd chose a different brand of X2 capacitors. They are not supposed to start burning if used under their voltage limit.   Frank

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