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bitrex <bitrex@de.lete.earthlink.net>: Jul 10 10:46AM -0400 Worth fixing up, or destined only for a new home on the scrap heap?   <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   Asking price is too high either way IMO

Foxs Mercantile <jdangus@att.net>: Jul 10 09:53AM -0500 On 7/10/2017 9:46 AM, bitrex wrote: > Worth fixing up, or destined only for a new home on the scrap heap?   > <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   > Asking price is too high either way IMO   There's cheaper alternatives to waste your time/money on. <http://www.ebay.com/itm/B-K-precision-520-MHZ-frequency-counter-/322577742771?hash=item4b1b21bbb3:g:3vkAAOSwVJhZWr8z>       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

"pfjw@aol.com" <pfjw@aol.com>: Jul 10 08:20AM -0700 On Monday, July 10, 2017 at 10:47:03 AM UTC-4, bitrex wrote: > Worth fixing up, or destined only for a new home on the scrap heap?   > <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   > Asking price is too high either way IMO   Rode hard and put away wet...   Short answer is a resounding NO.   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: Jul 10 11:32AM -0400 In article <CrM8B.143823$np2.14071@fx06.iad>, bitrex@de.lete.earthlink.net says...   > Worth fixing up, or destined only for a new home on the scrap heap?   > <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   > Asking price is too high either way IMO   Unless it is for some collection, I would send it off to the scrap heap. I would not even think about paying the postage if it was given to me.   Some old things are worth playing with if you have nothing else to do. I don't think this is even one of those.

Adrian Caspersz <email@here.invalid>: Jul 10 04:51PM +0100 On 10/07/17 15:46, bitrex wrote: > Worth fixing up, or destined only for a new home on the scrap heap?   > <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   > Asking price is too high either way IMO   Gut it out. Build in a PC. Sell it to a hipster.   -- Adrian C

bitrex <bitrex@de.lete.earthlink.net>: Jul 10 11:54AM -0400 > Short answer is a resounding NO.   > Peter Wieck > Melrose Park, PA   I appreciate the sanity-check ;-)

bitrex <bitrex@de.lete.earthlink.net>: Jul 10 11:54AM -0400 On 07/10/2017 11:51 AM, Adrian Caspersz wrote:   >> <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   >> Asking price is too high either way IMO   > Gut it out. Build in a PC. Sell it to a hipster.   It's got like, toobs, man. They sound warm

N_Cook <diverse@tcp.co.uk>: Jul 10 05:10PM +0100 On 10/07/2017 15:46, bitrex wrote: > Worth fixing up, or destined only for a new home on the scrap heap?   > <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company-Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   > Asking price is too high either way IMO   If you like NIXIs strip them out and use modern driving and build a room clock , with a wow factor

Cursitor Doom <curd@notformail.com>: Jul 10 04:21PM On Mon, 10 Jul 2017 17:10:39 +0100, N_Cook wrote:   > On 10/07/2017 15:46, bitrex wrote: >> Worth fixing up, or destined only for a new home on the scrap heap?   >> <http://www.ebay.com/itm/Vintage-Computer-Measurements-Company- Electronic-Counter-400-MC-Frequency-Conv/271738245865?ssPageName=STRK% 3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649>   >> Asking price is too high either way IMO   Deffo.     > If you like NIXIs strip them out and use modern driving and build a room > clock , with a wow factor   Nice idea that.

Jeff Liebermann <jeffl@cruzio.com>: Jul 09 10:20AM -0700 On Sun, 9 Jul 2017 15:10:46 -0000 (UTC), Cursitor Doom   >Gentlemen,   Surely, you jest.   >waveshape and knows what causes it, that'd be "awesome" - as our American >friends describe everything. Check it out:   >https://www.flickr.com/photos/128859641@N02/35684682551/in/dateposted-public/   Is the mystery load the hardware appearing in adjacent photos? EXIF says that they were taken 4 days earlier, which suggests a connection.   These photos looks odd: <https://www.flickr.com/photos/128859641@N02/34892442244/in/photostream/> <https://www.flickr.com/photos/128859641@N02/35564536392/in/photostream/> because C17 (the 2nd blue electrolytic from the right) seems to have been soldered into the wrong PCB holes. The white silk screen circle makes a good target for installing capacitors. If my crystal ball is correct, this capacitor might be presenting a higher than normal current load to the power supply, which is reacting by producing excessive ripple that you're seeing on the scope.   Is this the capacitor you removed from the board? <https://www.flickr.com/photos/128859641@N02/35050368241/in/photostream/> If so, you ripped out the plated through hole. 4 terminal radial caps are not common, so I guess you substituted something else. What did you put in its place? Did you test and fix the PCB traces?   Oh, never mind. I found your rather ugly solder wick PCB fix: <https://www.flickr.com/photos/128859641@N02/35602405551/in/photostream/> You might want to double (or triple) check your soldering and PCB through hole connections.   From this photo: <https://www.flickr.com/photos/128859641@N02/35564539582/in/photostream/> there's a tuning screw, semi-rigid coax cable, and cavity filter on the left side. Too bad the power supply board is missing. There are some gold connector pins in the photo. So, what is it?     -- 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

"Tim Williams" <tiwill@seventransistorlabs.com>: Jul 09 01:24PM -0500 If it's your signal generator thing, yes, it's very possible / likely to have dried out caps (excess ESR).   Yes, the nippley appearance is likely ESR. But, if you say it's okay, then it must be okay. Right?   Tim   -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website: http://seventransistorlabs.com   "Cursitor Doom" <curd@notformail.com> wrote in message news:ojth1m$vqg$1@dont-email.me...

Cursitor Doom <curd@notformail.com>: Jul 09 06:34PM On Sun, 09 Jul 2017 10:20:47 -0700, Jeff Liebermann wrote:   > Is the mystery load the hardware appearing in adjacent photos? EXIF > says that they were taken 4 days earlier, which suggests a connection.   If the adjacent photos were of any relevance, Jeff, I'd have mentioned it and linked to them.     > <https://www.flickr.com/photos/128859641@N02/35602405551/in/photostream/   > You might want to double (or triple) check your soldering and PCB > through hole connections.   All I did was replace an electro with one of identical parameters; it just happened to be a bit smaller than the original (which is not at all uncommon).     > there's a tuning screw, semi-rigid coax cable, and cavity filter on the > left side. Too bad the power supply board is missing. There are some > gold connector pins in the photo. So, what is it?   You're complicating this unduly and massively, Jeff. I simply posed a question about an oscilloscope trace, that's all.

mike <ham789@netzero.net>: Jul 09 12:34PM -0700 On 7/9/2017 8:10 AM, Cursitor Doom wrote: > friends describe everything. Check it out:   > https://www.flickr.com/photos/128859641@N02/35684682551/in/dateposted- > public/   You might get this when you have two caps separated by an inductor. First cap usually gets more peak charge current than the second one and develops high ESR first. Even if both caps are good, the inductor (or resistor) in between can cause this effect.

Cursitor Doom <curd@notformail.com>: Jul 09 08:44PM On Sun, 09 Jul 2017 12:34:51 -0700, mike wrote:   > First cap usually gets more peak charge current than the second one and > develops high ESR first. Even if both caps are good, the inductor (or > resistor) in between can cause this effect.   Someone on SER said a non-linear load could explain the shape of that trace and my initial reaction was that sounded quite plausible. However, on reflection I think if that *were* the case, then the knee would span 600-700mV (when the semis start conducting) and that isn't what we see here. The obvious thing to do next is whip off the output plugs from the PSU one by one and see if that clears the problem and if so, which sub- circuit is responsible for the overload as it may be nothing to do with the PSU at all.   -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Robert Baer <robertbaer@localnet.com>: Jul 09 02:04PM -0800 Cursitor Doom wrote: > friends describe everything. Check it out:   > https://www.flickr.com/photos/128859641@N02/35684682551/in/dateposted- > public/   Cause: stored charge in the rectifiers.

"David Eather" <eather@tpg.com.au>: Jul 10 08:17AM +1000 On Mon, 10 Jul 2017 01:10:46 +1000, Cursitor Doom <curd@notformail.com> wrote:   > friends describe everything. Check it out:   > https://www.flickr.com/photos/128859641@N02/35684682551/in/dateposted- > public/   a soft diode in the bridge rectifier?   -- Using Opera's mail client: http://www.opera.com/mail/

"tom" <tmiller11147@verizon.net>: Jul 09 07:37PM -0400 "David Eather" <eather@tpg.com.au> wrote in message news:op.y24qvzulwei6gd@fx-6300... >> public/   > a soft diode in the bridge rectifier?   > -- It is showing two half cycles at 50 Hz and they are the same. Most likely not a diode issue. Most likely a bad capacitor with high ESR. Or you got the replacement capacitor in the wrong holes on the pc board. Can you remove the new cap and get a photo of the top side of the board?

Phil Allison <pallison49@gmail.com>: Jul 09 04:40PM -0700 Foxs Mercantile wrote:     > Not sure what's causing it, but it's indicative of a non- > linear load. The "knee" is where the load transitions from > one value to a smaller value.   ** The "knee" or bump on the saw tooth is caused by electro cap ESR.   If you add a say a 1 ohm resistor in series, the bump will get much larger.   The bump is visible, along with ripple, on most unregulated DC supplies.       .... Phil

Tauno Voipio <tauno.voipio@notused.fi.invalid>: Jul 10 10:36AM +0300 On 9.7.17 23:44, Cursitor Doom wrote: > one by one and see if that clears the problem and if so, which sub- > circuit is responsible for the overload as it may be nothing to do with > the PSU at all.     The peak is definitely from the charge pulse from the rectifier. A capacitor-input PSU charges only 5 to 10 % of the half-cycle time, depending on the resistances and inductances in the charge path.   --   -TV

Phil Allison <pallison49@gmail.com>: Jul 10 01:38AM -0700 Tauno Voipio wrote:   ----------------------------------   > The peak is definitely from the charge pulse from the rectifier. A > capacitor-input PSU charges only 5 to 10 % of the half-cycle time, > depending on the resistances and inductances in the charge path.   ** Wrong on both claims.   The charging current pulse has the same duration as the rising part of the voltage waveform - about 15 to 30% of the half cycle period.   The bump is due to resistance in series with the capacitance - use a film cap and it disappears.         .... Phil

Cursitor Doom <curd@notformail.com>: Jul 10 09:58AM On Sun, 09 Jul 2017 19:37:39 -0400, tom wrote: - > likely not a diode issue. Most likely a bad capacitor with high ESR. Or > you got the replacement capacitor in the wrong holes on the pc board. > Can you remove the new cap and get a photo of the top side of the board?   When I tested this psu out-of-circuit with a dummy load I got less than 5mV of ripple on that rail. Now I may have too lightly-loaded the output, I can't say for sure, but that does tend to indicate to me I should check for shorted components down the line from the psu before I do anything else.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 09 07:13PM +0100 <mhooker32@gmail.com> wrote in message news:ce6b58ea-d6d6-4fa0-8e64-6042dfc63f20@googlegroups.com...   >> A ringer is the best instrument to check for shorted turns.   > not sure what a ringer is, but im pretty sure i dont have one. you mean > like a tone generator, and you move it around the yoke ?   The DSE one has a comparator rigged to generate spike pulses - the ringing pulses clock a logic 1 along a shift register and basically counts how many times the inductor rings.   The schematic is floating about the web, and there's nothing hard to find in the parts list.

Foxs Mercantile <jdangus@att.net>: Jul 09 01:43PM -0500 On 7/9/2017 1:13 PM, Ian Field wrote: > basically counts how many times the inductor rings.   > The schematic is floating about the web, and there's nothing > hard to find in the parts list.   <https://www.flippers.com/fbt-main.html>       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

mhooker32@gmail.com: Jul 09 02:50PM -0700 On Sunday, July 9, 2017 at 2:43:31 PM UTC-4, Foxs Mercantile wrote:   > --- > This email has been checked for viruses by AVG. > http://www.avg.com i swapped the D360 diode with another from the board, no difference. i dont really understand from the schematic what the pump up circuit is. it has 24V thru a electrolytic cap in series to pin7 . is that an input or an output? the same circuit( before the cap) goes to pin 3. there is only about 1/2 volt on pin 7. is it supposed to pulse, pin 7 pulling down the 24 v?

RoyceGrey@yahoo.com: Jul 09 11:05AM -0700 Hello!        I know this is besides the point, but I've got a unit conversion app that I'm releasing a new version of, and I thought I'd see if people around here would like to test it.        You can convert units and ratios.        You can convert two units at a time.        You can use fractions.        You have more units than you can shake a stick at (but don't, it make them mad).        So, if anyone wants it's here: https://play.google.com/apps/testing/appinventor.ai_RoyceGrey.Frank_Harr_s_Conversion_App

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