Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 18848354 times)

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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36850 on: August 13, 2019, 08:34:52 pm »
My car insurance policy also renews this month but luckily the payments are spread out monthly. And of course the rates went up again. I decided to shop around and I'm not finding anything cheaper to make it worth the effort to switch. Turns out I'm in that "senior citizen preferred rate" and it ain't gonna get any better....unless I decide to get rid of one car and then my rates would be almost cut in half.   
Yeah, likewise here, I'm in the same senior citizen bracket myself and we have a company over here called "Direct Line" and they reckon that they have the best rates and refuse to be on any of the compare websites. Meh, checked their quote, almost 50% higher then my current insurer who I must say have been very good so it looks like they have my money again this year.
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36851 on: August 13, 2019, 08:37:06 pm »
Here's the circuit in question. I have a strong pulse on the A sweep stop side of C824 and nothing on the other side. Which means no reset pulse to pin 16 of the IC. I thought the cap was bad. Nope. Checked both transistors and the diode. All good. Checked C821, R821, R826...all good. Proper voltages to the transistors. No shorts to ground on the line to pin 16...measures 1K as it should through R826.

The only thing I can figure is that there is a timing issue between A Gate Stop and A Sweep Stop which might possibly shut down the reset pulse to pin 16. Does that sound like a possibility?


Replace C824? it would appear to be effectively open.

I did replace it. Still no pulse. I checked the cap and it was good. That is what is so confusing and odd with this issue.
I did edit my earlier post, but I take it that you have physically checked that there is continuity between pin 16 and the collector of Q822?
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36852 on: August 13, 2019, 08:37:48 pm »
Maybe Q822/CR816 leaky, shunting to GND? Could lift pin at J816 see if it makes a difference.  :-//

mnem
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36853 on: August 13, 2019, 08:39:26 pm »
Here's the circuit in question. I have a strong pulse on the A sweep stop side of C824 and nothing on the other side. Which means no reset pulse to pin 16 of the IC. I thought the cap was bad. Nope. Checked both transistors and the diode. All good. Checked C821, R821, R826...all good. Proper voltages to the transistors. No shorts to ground on the line to pin 16...measures 1K as it should through R826.

The only thing I can figure is that there is a timing issue between A Gate Stop and A Sweep Stop which might possibly shut down the reset pulse to pin 16. Does that sound like a possibility?


Replace C824? it would appear to be effectively open.

I did replace it. Still no pulse. I checked the cap and it was good. That is what is so confusing and odd with this issue.
I did edit my earlier post, but I take it that you have physically checked that there is continuity between pin 16 and the collector of Q822?

Yep....full continuity.
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36854 on: August 13, 2019, 08:41:40 pm »
Maybe Q822/CR816 leaky, shunting to GND? Could lift pin at J816 see if it makes a difference.  :-//

mnem
 :popcorn:

Possible. Will do that tomorrow when I pick up on this mess again.  :palm:
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36855 on: August 13, 2019, 08:43:50 pm »
My gut reaction is... if no shorted caps, replace Q816, Q822, CR816 shotgun-style unless they're grievously expensive/unobtanium; if so replace one by one, least painful semis first. The balance is the assache factor of reassembling to test vs likelihood of handling damage. In my case, I tend to choose shotgun approach to minimize the latter.

mnem
*tzzzt*
« Last Edit: August 13, 2019, 08:49:31 pm by mnementh »
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36856 on: August 13, 2019, 09:11:39 pm »
My gut reaction is... if no shorted caps, replace Q816, Q822, CR816 shotgun-style unless they're grievously expensive/unobtanium; if so replace one by one, least painful semis first. The balance is the assache factor of reassembling to test vs likelihood of handling damage. In my case, I tend to choose shotgun approach to minimize the latter.

mnem
*tzzzt*

Q816 is a plastic NPN and Q822 is a plastic PNP. And chances are my parts mules have them so that's a good possibility too.

Edit, same with CR816.
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36857 on: August 13, 2019, 09:25:03 pm »
I gave up after S1. Was my attempt terminated early?

Looking for something to vegetate in front of now I've got through Star Trek Discovery (good), Disenchantment (excellent) and Rick and Morty (excellent)

Yes, we did. S1 wasn't remarkable, S2 was better, S3 is excellent, S4 was good but buggered up by Warner Brothers, S5 was pretty good.

Yeah, S1 of many shows still has the writers, actors, etc. settling into their roles. I usually tough it out until S2. If it's still no good (or gets worse), then I bail.

The writer (JMS) is extremely literate, plants "random" seeds that don't mature until the next season, and drops in all sorts of references to just about everything. You won't spot them all, but JMS commented on them on rec.arts.sf.tv.babylon5.moderated in real time. If you watch B5, after seeing an episode look at the relevant page on http://www.midwinter.com/lurk/countries/us/eplist.html

Wow! I wish I had this when I first watched B5. Now I'll have to watch it again. At least it's only 5 seasons. It's been quite some time since I've watched SG1. Time to watch that again, too.
.
Midwinter site is the edited highlights, looking backwards. The realtime interaction occurred on Usenet.

B5 started in 1994,when it was still possible to know the entire web. Basically you went to CERN.ch, and people notified that when they had a new site. There was even a best of web 1994 awards, preserved at https://botw.org/1994/awards/index.html
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36858 on: August 13, 2019, 09:28:12 pm »
Well thank you Captain Obvious. I know that. Duh.  :-DD It would be more a novelty more than anything else. Was just wondering if anyone has any experience with them.

Yes, and I advise avoiding them like the plague.

I bought a DS212 from ebay for a little short of eighty quid (that's about one hundred of your colonial dollars).

Initially I was well chuffed with it, but that changed after about 10 minutes of exploring the menus, when it decided to crash. Turning it off and on again had no effect; I was the proud owner of a (very small) brick.

I contacted the seller, who asked me to wait while they contacted their supplier regarding the issue, and after waiting to almost the point of the ebay case expiry, I contacted them again and was granted a full refund. They didn't even ask me to return the item. If you leave it long enough without turning it on(a few days) it will work again for a few minutes, but really, it's just a useless novelty.

The Tek TDS420A I got for about the same price was a much better investment... especially as it has all the options installed and came with 4 Tek x10 probes, a Tek x1/10 switchable, and 2 other x1/10 switchable probes (some nice quality German brand I never heard of), not to mention the user and service manuals


Hold it, we need to regroup. The question was not about the cheap miniature Chinese LCD scopes. Mnem muddied the waters by tossing them into the conversation. I'm not interested in those but thanks for the info.  :-+ My question is about the NLS mini CRT scopes you used to see advertised in the back of electronics magazines in the 1980's. There's one for sale on my local CL and while I realize it's usefulness is extremely limited it might be fun to play with.
Well you could use the equivalent Sinclair model (SC110) and after that you would cherish the NLS as 'having transitioned to a large-screen model'.
 

Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36859 on: August 13, 2019, 09:35:07 pm »
My gut reaction is... if no shorted caps, replace Q816, Q822, CR816 shotgun-style unless they're grievously expensive/unobtanium; if so replace one by one, least painful semis first. The balance is the assache factor of reassembling to test vs likelihood of handling damage. In my case, I tend to choose shotgun approach to minimize the latter.

mnem
*tzzzt*

Q816 is a plastic NPN and Q822 is a plastic PNP. And chances are my parts mules have them so that's a good possibility too.

Edit, same with CR816.

Have a look at http://w140.com/tek_xref_free.pdf from  http://w140.com/tekwiki/wiki/Reference_material

You may find there is a standard part number, not just the Tek number.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36860 on: August 13, 2019, 09:45:31 pm »
Maybe Q822/CR816 leaky, shunting to GND? Could lift pin at J816 see if it makes a difference.  :-//

mnem
 :popcorn:
Close to what I thought. Q822 leaking would not shunt the signal to GND, but swamp it level-wise.
 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36861 on: August 13, 2019, 09:50:34 pm »
I just did a quick check. I can harvest exact replacements for Q816, Q822, and CR816 out of my 465B parts mule.

Tomorrow's project.  :-+
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36862 on: August 13, 2019, 10:03:55 pm »
My very first PEBKAC   ;D


I SO miss UF.  :'( They were my lifeline back when I worked HellDesk... *Makes mental note to do a deep-dive again, as I'm all caught up on Schlock Mercenary*

But I can't blame Illiad for burning out after producing daily for like 2 decades.  :palm: Most of us don't even keep a life partner that long nowadays...  :o

Last time I looked they were recycling them from the beginning. Unfortunately it is quite difficult to notice that, unless you know what's happening.

Well, the first clue is right there in that example strip; ClunkBox monitors.  :-DD

It's been recycling with sporadic updates for more than 10 years. Illiad has had more than one "life paradigm shift" which caused his strip to go on hiatus; sometime for more than a year at a time. He made it OFFICIAL a decade or so ago. ;)

mnem
*Currently making a backup*
Your dresdencodak is missing a 'd'.

Some suggestions along those line:

http://monstersoupcomic.com/

http://www.girlgeniusonline.com/comic.php

http://killsixbilliondemons.com/

https://tapastic.com/series/Sammy

http://www.doesnotplaywellwithothers.com/

NSFW:
http://www.richwallaceart.com/shroud/
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36863 on: August 14, 2019, 02:16:21 am »
Maybe Q822/CR816 leaky, shunting to GND? Could lift pin at J816 see if it makes a difference.  :-//

mnem
 :popcorn:
Close to what I thought. Q822 leaking would not shunt the signal to GND, but swamp it level-wise.

I was thinking B-C leakage, like if an excessive input had cascaded that far down the chain. But Q822 leaking would tend to pull pin 16 HI thru R822 and/or R823 connected to +5V DCPL2. It would have to be both Q822 & CR816 to shunt any current to GND, and then we'd have some warm resistors there.

@med: C821 is an electrolytic; is it possibly a crunk tant?

I just did a quick check. I can harvest exact replacements for Q816, Q822, and CR816 out of my 465B parts mule.

Tomorrow's project.  :-+

Good luck!  :-+

mnem
*currently very low on current*
« Last Edit: August 14, 2019, 03:48:59 am by mnementh »
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36864 on: August 14, 2019, 04:30:50 am »
Your dresdencodak is missing a 'd'.

Some suggestions along those line:

http://monstersoupcomic.com/   http://www.girlgeniusonline.com/comic.php   http://killsixbilliondemons.com/ https://tapastic.com/series/Sammy   http://www.doesnotplaywellwithothers.com/   NSFW:
http://www.richwallaceart.com/shroud/

Ooooh... it's been years since I tuned into Girl Genius; sometime around Von Rijn's Automata. I kindof preferred the hand-penciled era; but I'm weird like that.

Thanks for the heads-up; linky fixed now. Poked around Kill6Billion while I relaxed a little... good hook. We'll see how I like it.

Another one I forgot in my list; a must-read from like a decade ago; FreakAngels.  https://readcomiconline.to/Comic/FreakAngels/Issue-1?id=95399

mnem
*toddling off to ded*
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Offline Brumby

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36865 on: August 14, 2019, 05:06:45 am »
Well, looky what just turned up...

... and no sign of the word "Amazon" anywhere to be seen.

I only had to wait three quarters of the day.....
 

Offline bitseekerTopic starter

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36866 on: August 14, 2019, 05:31:47 am »
Woohoo! So, what's first on your measuring agenda?
TEA is the way. | TEA Time channel
 

Offline Brumby

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36867 on: August 14, 2019, 06:08:16 am »
A quick test on a PSU I have hooked up to two LED strips under my desk (Absolutely fantastic for locating things that fall to the floor).

There are two separate pairs of wires running from the PSU.  Measure both legs on one side: 384mA - then measure each individually: 182mA and 204mA.  Considering the readings were flipping around 1-2mA (or more) just working around my desk, I call that a good result.  Love the zeroing feature.

I think I'm am happy.   :D
« Last Edit: August 14, 2019, 06:09:48 am by Brumby »
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36868 on: August 14, 2019, 06:35:18 am »
A quick test on a PSU I have hooked up to two LED strips under my desk (Absolutely fantastic for locating things that fall to the floor).

There are two separate pairs of wires running from the PSU.  Measure both legs on one side: 384mA - then measure each individually: 182mA and 204mA.  Considering the readings were flipping around 1-2mA (or more) just working around my desk, I call that a good result.  Love the zeroing feature.

I think I'm am happy.   :D
I call that a very neat party trick and as you said, the zeroing button is a great addition, enjoy your 210E, it's great tool to have at your disposal[emoji106]

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Offline Zucca

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36869 on: August 14, 2019, 07:48:06 am »
Please excuse my random outburst but fuck DHL in the fucking arse.

Ordered a new phone for one of the kids. Day 1 - driver can't find the address. Day 2 - driver can't find the address. Called up DHL, they got hold of the driver and told him to go back. No show! Phoned up customer services - fuck this I'll have to drive a 40 mile round trip to Slough to go and get it. They said, yeah sorted. Soo go back, delivery rescheduled for tomorrow. Use their online service to set it to pick up as their driver is a slack arse and get a 500 error. Phone customer services back, closed! CUNTS FROM HELL.

Edit: the demise of human society will occur because the average man does not care about the effects of his actions or lack thereof.

If I ponder about the "Back to the Future" movie:
1) nobody could see that giant network called internet coming
2) if they only know how many packages need to be delivered in 2019... imbarassing.

The entire post/package system will go balls up soon.

« Last Edit: August 14, 2019, 12:16:29 pm by zucca »
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Can't love what you don't know. Zucca
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36870 on: August 14, 2019, 08:07:01 am »
Thing that always gets me about the post system here is that it usually takes less time for stuff to get from the EU to here than it does from the UK to here.

Anyway last night was interesting. Got up in the middle of the night to go for a wee and stood on what I thought was a kids toy on the way back. Foot hurt like hell. Didn’t think much of it as I was half asleep. Well woke up this morning with my eldest having a panic because there were bloody footprints all up the hall. Turns out I stood on a cocktail stick my youngest was using for “art”. There is blood over everything: hall, bedroom carpet, bed, sheets. And my foot still hurts and I need to drive to fucking slough.

This is annoying mostly because I’ve got a week away from the stresses of work so I can concentrate on some TE and electronics projects and this is day one  :--  :-DD
 

Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36871 on: August 14, 2019, 08:12:04 am »
Here's the circuit in question. I have a strong pulse on the A sweep stop side of C824 and nothing on the other side. Which means no reset pulse to pin 16 of the IC. I thought the cap was bad. Nope. Checked both transistors and the diode. All good. Checked C821, R821, R826...all good. Proper voltages to the transistors. No shorts to ground on the line to pin 16...measures 1K as it should through R826.

The only thing I can figure is that there is a timing issue between A Gate Stop and A Sweep Stop which might possibly shut down the reset pulse to pin 16. Does that sound like a possibility?


Replace C824? it would appear to be effectively open.

I did replace it. Still no pulse. I checked the cap and it was good. That is what is so confusing and odd with this issue.

May I suggest one of these fancy Hameg component tester scopes?  ;)

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg2568363/#msg2568363



Very handy things. Btw, do Tek scopes have such a thing?  ;D
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 

Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36872 on: August 14, 2019, 08:16:08 am »
Please excuse my random outburst but fuck DHL in the fucking arse.

Ordered a new phone for one of the kids. Day 1 - driver can't find the address. Day 2 - driver can't find the address. Called up DHL, they got hold of the driver and told him to go back. No show! Phoned up customer services - fuck this I'll have to drive a 40 mile round trip to Slough to go and get it. They said, yeah sorted. Soo go back, delivery rescheduled for tomorrow. Use their online service to set it to pick up as their driver is a slack arse and get a 500 error. Phone customer services back, closed! CUNTS FROM HELL.

Edit: the demise of human society will occur because the average man does not care about the effects of his actions or lack thereof.

In Germany DHL means "Dauert Halt Länger" (takes even longer) which seems to be very true in your case.  :(
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36873 on: August 14, 2019, 11:29:12 am »
In Germany DHL means "Dauert Halt Länger" (takes even longer) which seems to be very true in your case.  :(
Heh... when I first saw that I read it as "Dauert Halt Lager", and my own poor internal translator said "Holds & takes beer...?"

Needless to say, I wasn't seeing a downside to the idea of a delivery company that specialized in beer...  :-DD

mnem
« Last Edit: August 14, 2019, 11:30:45 am by mnementh »
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #36874 on: August 14, 2019, 11:48:15 am »
In Germany DHL means "Dauert Halt Länger" (takes even longer) which seems to be very true in your case.  :(
Heh... when I first saw that I read it as "Dauert Halt Lager", and my own poor internal translator said "Holds & takes beer...?"

Needless to say, I wasn't seeing a downside to the idea of a delivery company that specialized in beer...  :-DD

mnem


 ;D

We are all victims of our prepossesions, aren't we?  8)

Edit:
Here, especially for you:
« Last Edit: August 14, 2019, 11:55:51 am by BU508A »
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 


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