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bruce2bowser@gmail.com: Jun 30 06:58AM -0700 > the reciever is off, will intermittently do relay click and loudness amber led(s) on the front will glow gradually, > off, and repeat till I unplug it. Back in 2003-2004, I took my reciever to a authorized sony service center that > did not know how to fix it   Would you spend the money to train somebody to fix something like that 18 years later - especially when you could be addressing more late-model stuff? (I'm just sayin')

Jeff Urban <jurb6006@gmail.com>: Jun 30 06:07AM -0700 >I prefer to use a hi-fi or entertainment contrivance that already >has proper external speakers and better bass/treble controls.   Bass and treble ? I have a design that will blow your mind. If your public email is good I'll send you the print. Once I find it.   We are talking +/- 20dB, bass turnover continuously variable from about 40 to 400 Hz, treble has the same +/- 20dB with the turnover continuously variable from about 3KHz to 7KHz.   The only thing I am working on now is to decrease the effect of the treble when the turnover is lowered, meaning it boosts more frequencies. The reason is that if you got it set to 7K that 20dB boost is not that much, it is just bringing to you that sweet timbre. Take it to 4KHz and we are talking blowing tweeters fast like. So when I am done it is only going to have +/- 20 when set to the highest turnover.   Actually I am pretty sure I can just put some cutable jumpers on the board to allow the full range at all settings for those who get their tweeters wholesale...   It is a different approach to tone controls and I think I saw it implemented in some unit somewhere, but not as advanced as mine. No variable turnover.   I used to have the circuit values figured out but I lost it dammit. Doesn't matter I can figure it out again fast enough.   Actually if I get it up and send it you'll see because of the topology the values are very easy to figure.   Worse comes to worse I got it on paper and I can just scan it, where it was anyway, there is no Spice file of it.

OGY <X@NOWHERE.COM>: Jun 29 12:26PM -0700 Looking for but not sure the technical name of the intermediated water bubbler bottle that goes between the vacuum pump and the bell jar that will clean the stuff that may appear in the bell jar as being evacuated so as not to contaminate the vacuum pump.   Got links would be helpful   Thank you.

Arie de Muynck <no.spam@no.spam.org>: Jun 30 11:32AM +0200 On 2019-06-29 21:26, OGY wrote: > so as not to contaminate the vacuum pump.   > Got links would be helpful   > Thank you.   Scrubber?

bruce2bowser@gmail.com: Jun 29 02:08PM -0700 On Sunday, June 2, 2019 at 7:54:17 PM UTC-4, Cursitor Doom wrote: > question that's causing some folks to misinterpret it. > Anyway, the first two respondents told me all I wanted to know so many > thanks to them and their excellent comprehension skills.   Though, how would you say captain obvious in dutch maybe? Kapitein duidelijke?

bruce2bowser@gmail.com: Jun 29 02:00PM -0700 On Monday, May 13, 2019 at 5:03:59 PM UTC-4, bitrex wrote: > arrays. They come in different number of output channels per chip, too. > there's likely maximum number of individual ICs that can be > daisy-chained before clock skew becomes a problem.   I'm sure an operating system could help there.

Robert Roland <fake@ddress.no>: Jun 29 08:29PM +0200 > This will be a rarely used tool, and will be stored in my non-climate >controlled outdoor shed.   > How do I best protect the surface   Rust is caused by oxygen and an electrolyte, which is usually water.   To keep oxygen and water away from the metal, cover the bare metal surfaces with something so that the oxygen and water do not come into contact with the metal. On a tool where the bare metal surfaces need to stay bare, paint will not work. A layer of oil is often a good option. Oil evaporates slowly, clings well to the metal and is relatively easy to wipe off before use.   With metal objects that are kept at outdoor temperature, condensation is the main problem (unless you leave it out in the rain). Metal has a relatively high heat capacity, so when the weather changes from cold and dry to warm and humid, the metal stays cold for a while, causing condensation. If you can keep your tool slightly warmer than the outside air, you will greatly reduce condensation and therefore rusting. You don't need climate control. You only need to keep it somewhat warm. -- RoRo

etpm@whidbey.com: Jun 29 09:48AM -0700 On Fri, 28 Jun 2019 03:59:55 -0700 (PDT), "pfjw@aol.com"   >https://makezine.com/2007/05/30/35-avr-oscilloscope-clock/   >Peter Wieck >Melrose Park, PA     I have seen both links. The top one charges $100.00 plus shipping for the kit minus a CRT. I may go this route. The bottom link is to the kit that is no longer available. But I can download the files for the PC boards and the code for the microcontrollers. I did mention this in my post. Eric

etpm@whidbey.com: Jun 29 09:51AM -0700 On Fri, 28 Jun 2019 16:06:50 +0100, Geo <nhhu-o3hu@dea.spamcon.org> wrote:   >https://www.ebay.com/itm/Oscilloscope-Clock-Kit-for-many-crt-types-Wifi-OR-gps-CRT-Cathode-ray-tube-Scope/303198819933?hash=item46980ed65d:g:84wAAOSw3dxbTimZ Yeah, I saw that kit. $170.00 and he doesnt't even show a picture of the clock display. It's too bad I didn't think about doing this a few years ago when a board could be had for $34.00! Eric

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John Robertson <spam@flippers.com>: Jun 28 10:31AM -0700 On 2019/06/27 7:59 p.m., Rheilly Phoull wrote:   >> ....   Phil   > Might pay to check around, comes up OK for me in Oz   Works fine for me in Vancouver, BC...   Nice schematics with valves instead of tubes. Must be some furren idear.   John ;-#)#

~misfit~ <shaun.at.pukekohe@gmail.com>: Jun 29 11:30PM +1200 On 28/06/2019 8:55 PM, Jeff Layman wrote: > are using, but try using it with all add-ons disabled ("Safe Mode" when using Firefox, for > instance). If that allows you to see the page, you have to go back to normal mode and switch each > off add-on in turn until you find the one which is stopping the page from displaying.   Works fine here in NZ and I'm using an adblocker AND an anti-tracking add-on (Privacy Badger, I recommend it highly) in Firefox, works in Chrome too.   -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM" David Melville   This is not an email and hasn't been checked for viruses by any half-arsed self-promoting software.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Jun 29 07:22AM -0700 On Thursday, June 27, 2019 at 7:05:37 PM UTC-7, Phil Allison wrote:   > Am I missing something?   > .... Phil Based on all the successful responses, the answer is obviously "YES!"

John Robertson <spam@flippers.com>: Jun 29 08:26AM -0700 On 2019/06/28 1:14 a.m., Phil Allison wrote:   > ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one.   > Could that be it ?   > ..... Phil   Hi Phil,   I use this site when I'm not sure where the problem is:   https://isitdownorjust.me/   Hope that helps!   John :-#)#

etpm@whidbey.com: Jun 29 09:37AM -0700 On Thu, 27 Jun 2019 16:53:56 -0700, dplatt@coop.radagast.org (Dave Platt) wrote:     >The physical size of the CRT doesn't matter very much (directly) but >a larger or different CRT may have different voltage or current >requirements.   Thanks Dave. I downloaded the datasheet for the Mullard tube and I'll compare it to my CRT when it arrives. Eric   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

bruce2bowser@gmail.com: Jun 28 02:55PM -0700 Yes. BTW, I'm one of many, many stupid, slow, never-should-have-been-allowed-into-college liberal arts majors. Also, I'm a former east-coast union electrician helper. So you'll have to excuse me when I ask you: what does 'acedic' mean?

John Robertson <spam@flippers.com>: Jun 28 03:45PM -0700 > Yes. > BTW, I'm one of many, many stupid, slow, never-should-have-been-allowed-into-college liberal arts majors. Also, I'm a former east-coast union electrician helper. So you'll have to excuse me when I ask you: what does 'acedic' mean?   Acidic - vinegar based solvent. It was miss-speled.   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."

amdx <nojunk@knology.net>: Jun 29 08:20AM -0500 On 6/20/2019 5:20 PM, Jeff Liebermann wrote:   > That's tarnish (sulfur compounds). Some clues from how to clean brass > clock mechanisms: > <https://www.snclocks.com/TechnicalInformation/Tid-Bits/Clock-Cleaning-Solution/>   All very interesting and ties into my latest purchase. I bought a metal brake to bend flashing in my house. It came coated in oil, which I removed just by wiping with a paper towel, because it was so messy. Within two days in my screened porch it started to rust. So while I'm not using it, I used motor oil on a paper towel to re-oil the metal surfaces. This will be a rarely used tool, and will be stored in my non-climate controlled outdoor shed.   How do I best protect the surface   Ditto, my new drill press!.   Mikek

Jeff Liebermann <jeffl@cruzio.com>: Jun 29 09:35AM -0700 >How do I best protect the surface >Ditto, my new drill press!. > Mikek   Motor oil might work. I've never tried it. I use automotive grease on my drill press. Just about any grease or liquid wax that doesn't run, melt, or wash off should work. I've also used liquid furniture wax.   There are a wide variety of marine corrosion protection sprays and pastes available. <https://www.theruststore.com/Protect-Your-Boat-from-Rust-W39.aspx> <https://www.theruststore.com/Rust-Prevention-C4.aspx>   Also, automotive rust inhibitors: <https://www.eastwood.com/eastwood-heavy-duty-anti-rust-in-amber.html>   WD-40 Long Term Corrosion Inhibitor: <https://www.wd40specialist.com/products/corrosion-inhibitor/> <https://antonpug.com/blog/2015/5/11/diy-rust-protection-test>   You might search or ask the same question on: <https://www.cnczone.com/forums/> The forum is mostly about CNC machines, but also covers other aspects of machining. For example: <https://www.cnczone.com/forums/benchtop-machines/86146-rust-prevention.html>       -- 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

bruce2bowser@gmail.com: Jun 28 03:06PM -0700 >> 120 can be just as lethal as 240. >> (its the current, not the volts that's the problem in those accidents)   > But not nearly as fast or as certain.   Otherwise 120v ground fault protection would never trip as early as sensing just 5 milliamps.

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etpm@whidbey.com: Jun 27 04:28PM -0700 Well, I've been gone for a month and this group is dead. So maybe my questions will liven it up some. Or maybe everyone else is also on vacation. I know, this is a repair group. But I will no doubt need to repair whatever I build. And besides, I get better electronics advice here, as in more of it and correct, than on the basics group. While wasting some time on the computer while being on hold I came across some small ocsilloscope CRTs, then looking for something to light one of them up I saw some kits to make oscilloscope clocks. Only 34 bucks for the kit! So I ordered a two inch CRT with electrostatic deflection. Here's a link to the CRT I ordered: https://www.ebay.com/itm/5LO38I-Mini-5-cm-CRT-oscilloscope-cathode-ray-tube-FOR-DIY-NOS-BOXED/111978397405?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3Da8915a4a567c484c94f5f3b2d9e743c4%26pid%3D100675%26rk%3D4%26rkt%3D15%26mehot%3Dag%26sd%3D401706260380%26itm%3D111978397405&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3Afb320543-9930-11e9-9594-74dbd1808485%7Cparentrq%3A9b35da7016b0aa19f93d280effb7f16e%7Ciid%3A1 Then on to ordering the kit. Hah! No dice. The kits are no longer available. But I think I can still download the code for the microcontrollers and the files for the circuit boards. Here is a link to the page that the kit used to be available from: http://www.dutchtronix.com/ScopeClockH3-1-Enhanced.htm The kit was also available from other sources but I can't find it for sale anywhere. Darn. Maybe someone here bought one of these kits and never built it and it is collecting dust. If so why not sell it to me? I also need to drive the CRT and I found a simple circuit called the Mullard's Pupil Oscilloscope. Here's a link: https://www.instructables.com/id/Mullard-Pupils-Oscilloscope/ So, if I build the Mullard scope circuit will it drive the two inch CRT I ordered seeing as how it was made to drive a 1 inch CRT? And if that works will the Dutchtronix clock circuit work with the Mullard scope and give me a nice looking display? Look, this is just for fun. I am capable of safely dealing with the high voltage. But I don't know enough to know if all the parts will play nice with each other. I have also not built any tube or valve gear using point to point wiring so a little advice about that would be greatly appreciated. When it is all done the idea is to have as much of the tube circuitry as possible exposed with the modern microntroller stuff hidden away. I like tube stuff and exposed machinery, always have. I think a one tube scope with a hand wound xmfr could look pretty cool sitting on a shelf near my tube amplifier. Thanks All, Eric

dplatt@coop.radagast.org (Dave Platt): Jun 27 04:53PM -0700 In article <bkiahetm7sd5tu5le62altohhbp9vnevra@4ax.com>, >inch CRT I ordered seeing as how it was made to drive a 1 inch CRT? >And if that works will the Dutchtronix clock circuit work with the >Mullard scope and give me a nice looking display?   Maybe. :-)   In principle it ought to work, if you get the voltages correct. If you don't, it'll either not work, or damage the CRT or something else.   Among the things you'll need to look at, in matching up the various circuits and components, are;   - The required heater (filament) voltage and current for the CRT you are using. - The cathode, grid and deflection voltages for the CRT you are using. - The voltages being created by the clock circuit (microprocessor) and being fed to the X and Y inputs of the scope circuit   Read through the data sheet for the DH3-91 CRT that the circuit was designed to work with (http://www.labguysworld.com/1CP1(db3-91).pdf) and for the CRT you bought.   The physical size of the CRT doesn't matter very much (directly) but a larger or different CRT may have different voltage or current requirements.

John Robertson <spam@flippers.com>: Jun 27 04:57PM -0700 > cool sitting on a shelf near my tube amplifier. > Thanks All, > Eric   Looks like a fun project! Make some PCBs and offer them here, I'd probably buy one just for fun. I've got a few 'scopes sitting around that aren't doing anything useful...   As for the Mullard scope, it should work with a larger tube, you just may have to raise the deflection voltage a bit. Find the specs on the two tubes to see what the deflection differences are - if any!   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."

Phil Allison <pallison49@gmail.com>: Jun 27 07:05PM -0700 > https://www.instructables.com/id/Mullard-Pupils-Oscilloscope/   ** No pics or diagram showing up for me.   Am I missing something?     .... Phil

Rheilly Phoull <rheilly@bigslong.com>: Jun 28 10:59AM +0800 On 28/06/2019 10:05 am, Phil Allison wrote:   > .... Phil   Might pay to check around, comes up OK for me in Oz

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Jun 28 05:49AM +0200 On 28.06.19 4:05, Phil Allison wrote:   > Am I missing something?   > .... Phil   Loads fine here(Netherlands). Interesting circiut diagram. Needs a few mods, if you dont want a 12v supply.

Phil Allison <pallison49@gmail.com>: Jun 28 01:14AM -0700 Sjouke Burry wrote:   > Loads fine here(Netherlands).   ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one.   Could that be it ?     .... Phil

Jeff Layman <jmlayman@invalid.invalid>: Jun 28 09:55AM +0100 On 28/06/19 09:14, Phil Allison wrote:   > ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one.   > Could that be it ?   > .... Phil   I doubt it. I am using an adblocker and see the page without problem. I don't know what browser you are using, but try using it with all add-ons disabled ("Safe Mode" when using Firefox, for instance). If that allows you to see the page, you have to go back to normal mode and switch each off add-on in turn until you find the one which is stopping the page from displaying.   --   Jeff

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 28 03:59AM -0700 http://oscilloscopeclocknixiecrt.com/Kit.htm   https://makezine.com/2007/05/30/35-avr-oscilloscope-clock/   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Jun 28 04:36AM -0700 On Friday, June 28, 2019 at 4:14:28 AM UTC-4, Phil Allison wrote:   > ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one.   > Could that be it ?   > .... Phil     Odd.. You can try converting the web page to a .pdf right on line. If you can open this: https://webpagetopdf.com/ or one the many like it, input the instructables url and it will convert it to .pdf.

Geo <nhhu-o3hu@dea.spamcon.org>: Jun 28 04:06PM +0100 https://www.ebay.com/itm/Oscilloscope-Clock-Kit-for-many-crt-types-Wifi-OR-gps-CRT-Cathode-ray-tube-Scope/303198819933?hash=item46980ed65d:g:84wAAOSw3dxbTimZ

Don Brown <edfredcorp@gmail.com>: Jun 27 11:29AM -0700 On Wednesday, June 26, 2019 at 9:10:30 PM UTC-7, Don Brown wrote:   > I took some photos of when it is at it's best:   > Here is a sample curve trace - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Curve%20Test%20Scope%20Screenshot%20Working.jpg   > Here is the calibration screen, fairly normal I think with two steps per division as expected - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Calibration%20Scope%20Screenshot%20Working.jpg   OK, it has been stable for hours. I repeatedly cleaned and worked all switches and adjusted component clearances to avoid possible touching to case. Also gently flexed the pc board looking for sources of intermittent signs.   Maybe the non electrolytic capacitors needed time to reform, though I did not think it mattered to those.   At this point I did not address the 13v-14v power supply deficit, since it seems to be working. If anybody thinks I should address that for better precision, I will.   Also now have the Heathkit manual for review.   Thanks for all the tips from everybody.

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Jeff Urban <jurb6006@gmail.com>: Jun 26 12:59PM -0700 You can't attach things here. Bama probably has it but I can't confirm it right now because of this wonky MODEM that is going back to SBC with stab wounds, three bullet holes and half burned by a Bernzomatic torch. I am seriously about to jump ship but the only other thing I can get here is Hughesnet and in this area since there is a temporary rain forest to the south every year it is going to drop when it rains south of here just like the Dish TV thing.   But you probably got it online, just throw up a link.   I suppose I don't have to tell you to scrutinize every small signal PNP in there right ?   Nice thing is they all work the same. You should be able to put a low value resistor on the base drive and derive current that way. the noise and whatever have to be there. You can leave that on one channel of the scope and just start going backwards with the other. Unless you already have, if you are sure it is at the beginning of the "chain".   Nice to have it localised of course but when things get old they get weird failure modes. I have seen PC boards that worked for more than a decade and then came to me and looking for a bad connection on the board bending things a huge piece of solder simply came off the copper. It wasn't clean enough when they wave soldered it but it took all that time to manifest itself.   I think on this unit you are probably down to the small caps. some of them like to be a piece of wire sometimes.   More later, I am going to go shoot the MODEM. Don't worry I got another one.

Fox's Mercantile <jdangus@att.net>: Jun 26 03:51PM -0500 On 6/26/19 2:59 PM, Jeff Urban wrote: > Bama probably has it but I can't confirm it right now   They don't. <http://bama.edebris.com/manuals/hickok/>   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Don Brown <edfredcorp@gmail.com>: Jun 26 01:53PM -0700 On Wednesday, June 26, 2019 at 1:51:20 PM UTC-7, Fox's Mercantile wrote: > Jeff-1.0 > WA6FWi > http:foxsmercantile.com   I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.

Don Brown <edfredcorp@gmail.com>: Jun 26 03:00PM -0700 On Wednesday, June 26, 2019 at 1:53:53 PM UTC-7, Don Brown wrote: > > WA6FWi > > http:foxsmercantile.com   > I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.   Here is a photo gallery that I created with the schematic and circuit description: http://www.edfredcorp.com/Hickok/httphotos/index.html

Don Brown <edfredcorp@gmail.com>: Jun 26 03:40PM -0700 On Wednesday, June 26, 2019 at 1:53:53 PM UTC-7, Don Brown wrote: > > WA6FWi > > http:foxsmercantile.com   > I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.   Here is a photo gallery that I created with the schematic and circuit description: http://www.edfredcorp.com/Hickok/httphotos/index.html   And an enlarged schematic link: http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickock%20440%20Schematic.jpg

Don Brown <edfredcorp@gmail.com>: Jun 26 03:42PM -0700 On Wednesday, June 26, 2019 at 1:53:53 PM UTC-7, Don Brown wrote: > > WA6FWi > > http:foxsmercantile.com   > I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.   Here is a photo gallery that I created with the schematic and circuit description: http://www.edfredcorp.com/Hickok/httphotos/index.html   And here is a link for a high resolution schematic: http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickock%20440%20Schematic.jpg

Don Brown <edfredcorp@gmail.com>: Jun 26 04:17PM -0700 On Wednesday, June 26, 2019 at 3:42:36 PM UTC-7, Don Brown wrote:   > > I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.   > Here is a photo gallery that I created with the schematic and circuit description: http://www.edfredcorp.com/Hickok/httphotos/index.html   > And here is a link for a high resolution schematic: http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickock%20440%20Schematic.jpg   By temporarily reducing the resistance of R22 & R23 in the 15+ & 15- I was able to bring up voltages to exactly 15v.That does heat up the zeners, which I upgraded from 1/2W to 15v 1W. No change on stability issue.

John Robertson <spam@flippers.com>: Jun 26 08:06PM -0700 On 2019/06/26 3:42 p.m., Don Brown wrote:   >> I looked everywhere for it and ended up buying the hard copy. So I need to scan it and link it.   > Here is a photo gallery that I created with the schematic and circuit description: http://www.edfredcorp.com/Hickok/httphotos/index.html   > And here is a link for a high resolution schematic: http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickock%20440%20Schematic.jpg   Hi Dan,   The Heathkit IT-1121 curve tracer is somewhat similar to your schematic. Have you read that manual?   Pretty sure you can download it from www.tech-systems-labs.com - use web.archive.org and look in 2007 archives...   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."

Don Brown <edfredcorp@gmail.com>: Jun 26 09:10PM -0700 On Wednesday, June 26, 2019 at 8:06:47 PM UTC-7, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."   I will review the Heathkit manual. I am new to curve tracers and have several manuals to study and plenty to learn.   My problem is intermittent. Cannot find what causes it yet. It does not change with length of time on (heat), case open or closed, switch movements or settings, tapping components. Maybe she is like me, getting old and not consistently useful.   I took some photos of when it is at it's best:   Here is a sample curve trace - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Curve%20Test%20Scope%20Screenshot%20Working.jpg   Here is the calibration screen, fairly normal I think with two steps per division as expected - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Calibration%20Scope%20Screenshot%20Working.jpg

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whit3rd <whit3rd@gmail.com>: Jun 26 02:46AM -0700 On Tuesday, June 25, 2019 at 6:54:49 AM UTC-7, Don Brown wrote: > I have a Hickok 440 curve tracer that I am having difficulty troubleshooting, even though it is a relatively simple circuit.   > The base generator staircase is not stable     Typically, there's a monostable making a current pulse into a capacitor for each step. If the capacitor is an electrolytic, it may be leaky now (but run the staircase overnight before you replace parts, it may be that some ON-time will reform the oxide layer). If the monostable has a capacitor, it is also a suspect (unstable times).   Resetting the staircase there's a charge-dump (transistor?) that could be leaky, or its drive might be picking up noise. Hanging an o-scope probe onto the step generator to show the rise/plateau qualities will tell where the problem lies.

Don Brown <edfredcorp@gmail.com>: Jun 26 08:15AM -0700 On Wednesday, June 26, 2019 at 2:46:50 AM UTC-7, whit3rd wrote:   > Resetting the staircase there's a charge-dump (transistor?) that could be leaky, or its > drive might be picking up noise. Hanging an o-scope probe onto the step generator > to show the rise/plateau qualities will tell where the problem lies   Yes, this is the way it works. I should attach the schematic and circuit description. It charges a ceramic non electrolytic capacitor, with a diode in line that keeps it from discharging each pulse. But since ceramics rarely fail I did not change it, but maybe I should. And from previous scope probing I saw various qualities of pulses but did not really understand what was normal and what was not.   Thank you.

fahmisant29@gmail.com: Jun 26 12:41AM -0700 Hello sir, Can i get Electronic principles by Malvino 8th ed manual solution? Thank you

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Don Brown <edfredcorp@gmail.com>: Jun 25 06:54AM -0700 I have a Hickok 440 curve tracer that I am having difficulty troubleshooting, even though it is a relatively simple circuit.   The base generator staircase is not stable, and will not stay in calibration. It looks like noise comes and goes and distorts it. I have replaced most of the semiconductors. The 15v power supply is a bit low at about 13.9v, though the regulator transistor and zeners have been replaced.   I have the manual, schematic, parts and usual test equipment.   Thank you, Don

John Robertson <spam@flippers.com>: Jun 25 08:00AM -0700 On 2019/06/25 6:54 a.m., Don Brown wrote:   > I have the manual, schematic, parts and usual test equipment.   > Thank you, > Don   Have you replaced any and all electrolytic capacitors and verified that the resistors are on spec?   Capacitors are bigger suspects than the semiconductors...   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."

Don Brown <edfredcorp@gmail.com>: Jun 25 08:07AM -0700 On Tuesday, June 25, 2019 at 6:54:49 AM UTC-7, Don Brown wrote:   > I have the manual, schematic, parts and usual test equipment.   > Thank you, > Don   I changed the two electrolytics in the 15v supply, and one polyester that is used in the base generator section (though it tested OK out of circuit). I did a quick run through on the resistors while in circuit, and they test within spec with nothing unusual.

Ralph Mowery <rmowery28146@earthlink.net>: Jun 25 11:08AM -0400 In article <o--dnbQEfIK0qo_AnZ2dnUU7-S2dnZ2d@giganews.com>, spam@flippers.com says...   > Have you replaced any and all electrolytic capacitors and verified that > the resistors are on spec?   > Capacitors are bigger suspects than the semiconductors...   In older equipment it is always to suspect the electrolytic capacitors first. For older tube equipment the 1/2 and 1 watt carbon resistors often seem to go up in value and are the next thing after the capacitors I check for equipment that is sort of working,but not up to specifications.

Don Brown <edfredcorp@gmail.com>: Jun 25 08:09AM -0700 On Tuesday, June 25, 2019 at 6:54:49 AM UTC-7, Don Brown wrote:   > I have the manual, schematic, parts and usual test equipment.   > Thank you, > Don   So the short answer is Yes.

John Robertson <spam@flippers.com>: Jun 25 08:50AM -0700 On 2019/06/25 8:09 a.m., Don Brown wrote:   >> Thank you, >> Don   > So the short answer is Yes.   OK, caps and resistors all good.   Then I'd scope the existing power supply to make sure it is clean & stable.   If you have a good bench power supply see if using a different +15VDC source clears up the issue.   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."

Don Brown <edfredcorp@gmail.com>: Jun 25 09:16AM -0700 On Tuesday, June 25, 2019 at 8:50:33 AM UTC-7, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."   I can do both. I did not think of an external power supply, will report back and post results.   Thank you

bruce2bowser@gmail.com: Jun 24 10:26AM -0700 > > Computers should not be run in the rain, they need to be protected from > > the weather...unless specifically designed for outdoor all-weather use!   > I dunno - were the OP to hold a 240 VAC power-supply for that computer between his legs in a driving rain, it may have a salubrious effect.   120 can be just as lethal as 240. (its the current, not the volts that's the problem in those accidents)

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 24 12:12PM -0700 > 120 can be just as lethal as 240. > (its the current, not the volts that's the problem in those accidents)   But not nearly as fast or as certain.

Rheilly Phoull <rheilly@bigslong.com>: Jun 25 10:04AM +0800 >> 120 can be just as lethal as 240. >> (its the current, not the volts that's the problem in those accidents)   > But not nearly as fast or as certain.   And given the high resistance of the human bod I feel they are interactive, you cant have a current through high resistance with low voltage

Lucifer <LuciferMorningstar@bigpond.com>: Jun 25 07:53PM +1000 >> with an adaptor which means the surge wudda had to jump the induction coild >> (unlikely). I realy want to put som erational persectiv eon this.   >You should consult Skybuck Flying, he is reasoning along the same lines.   Af lakeys pacebar?

Lucifer <LuciferMorningstar@bigpond.com>: Jun 25 07:57PM +1000 On Mon, 24 Jun 2019 08:44:26 -0700, John Robertson <spam@flippers.com> wrote:     >Computers should not be run in the rain, they need to be protected from >the weather...unless specifically designed for outdoor all-weather use!   >John ;-#)#   Her eallyn eedsa spellc hequera ndp roofr eading.

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 25 04:39AM -0700 On Monday, June 24, 2019 at 10:04:12 PM UTC-4, Rheilly Phoull wrote:   > And given the high resistance of the human bod I feel they are > interactive, you cant have a current through high resistance with low > voltage   The (healthy adult) human body is, effectively, a 10,000 ohm, 1/4-watt resistor. Anything that will put more than 1/4 watt through 10,000 ohms will cause damage.   Peter Wieck Melrose Park, PA

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Rob <nomail@example.com>: Jun 24 01:45PM > Ever since, I hesitate using my computers in the rain. And the laptop ran > with an adaptor which means the surge wudda had to jump the induction coild > (unlikely). I realy want to put som erational persectiv eon this.   You should consult Skybuck Flying, he is reasoning along the same lines.

John Robertson <spam@flippers.com>: Jun 24 08:44AM -0700 On 2019/06/24 6:45 a.m., Rob wrote: >> with an adaptor which means the surge wudda had to jump the induction coild >> (unlikely). I realy want to put som erational persectiv eon this.   > You should consult Skybuck Flying, he is reasoning along the same lines.   The OP said:   "Ever since, I hesitate using my computers in the rain."   Computers should not be run in the rain, they need to be protected from the weather...unless specifically designed for outdoor all-weather use!   John ;-#)#

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 24 09:00AM -0700 On Monday, June 24, 2019 at 11:44:34 AM UTC-4, John Robertson wrote:     > "Ever since, I hesitate using my computers in the rain."   > Computers should not be run in the rain, they need to be protected from > the weather...unless specifically designed for outdoor all-weather use!   I dunno - were the OP to hold a 240 VAC power-supply for that computer between his legs in a driving rain, it may have a salubrious effect.   Peter Wieck Melrose Park, PA

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Lucifer <LuciferMorningstar@bigpond.com>: Jun 22 10:41AM +1000 On Tue, 18 Jun 2019 17:24:44 -0700, John Robertson <spam@flippers.com> wrote:     >I'd like to argue with the manufacturers, but they stopping making the >games we fix back in the mid to late 90s...so I'm stuck with tinned >contacts and trying to extend their useful life.   What about wire wrap and insulation displacement connections?

John Robertson <spam@flippers.com>: Jun 21 06:31PM -0700 On 2019/06/21 5:41 p.m., Lucifer wrote: >> games we fix back in the mid to late 90s...so I'm stuck with tinned >> contacts and trying to extend their useful life.   > What about wire wrap and insulation displacement connections?   No wire wrap used in our commercial games, but an EPROM copier I made up back in the 70s worked when I last tested it in the late 90s. It is sitting in a drawer but unlikely to be used again as I have much better tools these days.   Insulation displacement? Don't make me laugh - those are quite the pain over crimped Molex pins. Lots of failures with power connectors on the insulation displacement connectors. Seemed to be related to the pin tension - they didn't grab the pin as well as the original design, certainly not as well as Trifurcon pins.   John :-#(#

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