Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

@med, I think I have just spotted another problem for you, take a look at the attached photo, the blue tubular cap? 2nd one down does not seem to be connected at all, the hole where it should be soldered to is open??? 

[med6753]

This is getting real intense. It's looking more and more like I have a short in the board itself.  I've pulled and isolated just about every component hanging on the +15V bus and it's still shorted to ground. As much as I don't want to do it I'm going to cut the land in a choice spot where it branches in two directions and see what happens. 

Bring in a 15v (limit the current to say 1A) supply from your bench PSU and if you have either a thermal imaging camera or even a infra-red thermometer look around the board for signs of extra heat. If you don't have either, then you could use something like lighter fuel spread in areas on the board and components, (not too much as to make it a hazard) and then look for areas where the fuel evaporates quickest due to the increased temperature caused by the short circuit and then bingo, you'll have found the source of your problem.

I think IPA would probably be a better choice although it does evaporate pretty quickly on it own.

[med6753]

@med, I think I have just spotted another problem for you, take a look at the attached photo, the blue tubular cap? 2nd one down does not seem to be connected at all, the hole where it should be soldered to is open??? 

Nope, they are connected.

[Specmaster]

This is getting real intense. It's looking more and more like I have a short in the board itself.  I've pulled and isolated just about every component hanging on the +15V bus and it's still shorted to ground. As much as I don't want to do it I'm going to cut the land in a choice spot where it branches in two directions and see what happens. 

Bring in a 15v (limit the current to say 1A) supply from your bench PSU and if you have either a thermal imaging camera or even a infra-red thermometer look around the board for signs of extra heat. If you don't have either, then you could use something like lighter fuel spread in areas on the board and components, (not too much as to make it a hazard) and then look for areas where the fuel evaporates quickest due to the increased temperature caused by the short circuit and then bingo, you'll have found the source of your problem.

I think IPA would probably be a better choice although it does evaporate pretty quickly on it own.

Yep it does and I think that maybe why I have noticed that quite a lot of YouTubers use lighter fluid because it will totally evaporate in a few minutes and does zero damage but will visibly evaporate far quicker in any areas where there is extra heat such as a short circuit.   

[Cubdriver]

This Dana 5330 voltmeter listed on ePay.com in the wrong category may be of interest here, it has nixie bulbs:
eBay auction: #254237958335

David

Damn you!!!       

Hmm. Does that mean you own it now? Looking forward to the teardown.

I was hesitant to answer this earlier, given my experience a year or so ago with the Fluke that I bought that turned out to be either lost or "failed testing and was scrapped" by the vendor (after having been listed and sold as "for parts or not working"  ), but it has now been marked as shipped, so I hope I am safe in saying yes, I bought it.  Why, you might ask?  Well, it has nixies in it, and I don't have one of THAT particular model yet.  Reason enough for a TEA addict.  (And I'd been doing kind of well with staying off the Bay of Iniquity, too, dammit!)

-Pat

[mnementh]

We'll be holding a vigil for your sanity in the chapel pending delivery. You figure what; Thursday-ish...? 

mnem
*agitating-ily* 

[Cubdriver]

ETA shows as between the 7th and the 9th, though of course it's not yet scanned into the system so that's just a guess for now...

-Pat

[0culus]

I need more Nixie tubes. I was considering getting one of those fancy clock kits....but a nixie counter would be super tasty on the bench.  Currently the only nixies I have is that Nonlinear Systems voltmeter.

[Brumby]

When I read this:

This is getting real intense. It's looking more and more like I have a short in the board itself.  I've pulled and isolated just about every component hanging on the +15V bus and it's still shorted to ground. As much as I don't want to do it I'm going to cut the land in a choice spot where it branches in two directions and see what happens. 

This outcome was my first thought:

I made what I thought was a strategic cut in the land and BOTH sides still reading short to ground. I think I need to step away from this for today and start fresh in the morning. 

[Kosmic]

This is getting real intense. It's looking more and more like I have a short in the board itself.  I've pulled and isolated just about every component hanging on the +15V bus and it's still shorted to ground. As much as I don't want to do it I'm going to cut the land in a choice spot where it branches in two directions and see what happens. 

Bring in a 15v (limit the current to say 1A) supply from your bench PSU and if you have either a thermal imaging camera or even a infra-red thermometer look around the board for signs of extra heat. If you don't have either, then you could use something like lighter fuel spread in areas on the board and components, (not too much as to make it a hazard) and then look for areas where the fuel evaporates quickest due to the increased temperature caused by the short circuit and then bingo, you'll have found the source of your problem.

I think IPA would probably be a better choice although it does evaporate pretty quickly on it own.

Yep it does and I think that maybe why I have noticed that quite a lot of YouTubers use lighter fluid because it will totally evaporate in a few minutes and does zero damage but will visibly evaporate far quicker in any areas where there is extra heat such as a short circuit.   

You could also use freeze spray. But it tend to leave water all over the place.

To find shorts, I had some success using y 34401a in ohms mode.

[Specmaster]

This is getting real intense. It's looking more and more like I have a short in the board itself.  I've pulled and isolated just about every component hanging on the +15V bus and it's still shorted to ground. As much as I don't want to do it I'm going to cut the land in a choice spot where it branches in two directions and see what happens. 

Bring in a 15v (limit the current to say 1A) supply from your bench PSU and if you have either a thermal imaging camera or even a infra-red thermometer look around the board for signs of extra heat. If you don't have either, then you could use something like lighter fuel spread in areas on the board and components, (not too much as to make it a hazard) and then look for areas where the fuel evaporates quickest due to the increased temperature caused by the short circuit and then bingo, you'll have found the source of your problem.

I think IPA would probably be a better choice although it does evaporate pretty quickly on it own.

Yep it does and I think that maybe why I have noticed that quite a lot of YouTubers use lighter fluid because it will totally evaporate in a few minutes and does zero damage but will visibly evaporate far quicker in any areas where there is extra heat such as a short circuit.   

You could also use freeze spray. But it tend to leave water all over the place.

To find shorts, I had some success using y 34401a in ohms mode.

Yeh, the advantage with the fluid method is that it is far quicker to locate without having to isolate one end of each part, find the dry spot, and that is where the heat is, jackpot.

[bitseeker]

This Dana 5330 voltmeter listed on ePay.com in the wrong category may be of interest here, it has nixie bulbs:
eBay auction: #254237958335

David

Damn you!!!       

Hmm. Does that mean you own it now? Looking forward to the teardown.

I was hesitant to answer this earlier, given my experience a year or so ago with the Fluke that I bought that turned out to be either lost or "failed testing and was scrapped" by the vendor (after having been listed and sold as "for parts or not working"  ), but it has now been marked as shipped, so I hope I am safe in saying yes, I bought it.

No need to hesitate. Things happen, even after they've shipped. *sigh* If you've paid, that's close enough to ownership in this neck of the woods (until the situation changes, of course).

Why, you might ask?  Well, it has nixies in it, and I don't have one of THAT particular model yet.  Reason enough for a TEA addict.  (And I'd been doing kind of well with staying off the Bay of Iniquity, too, dammit!)

No, I'll not ask that. TEAmateurs might.

I need more Nixie tubes. I was considering getting one of those fancy clock kits....but a nixie counter would be super tasty on the bench.

Yep, that's how four Nixie counters ended up finding their way to my lab. Beware!

[bitseeker]

(And I'd been doing kind of well with staying off the Bay of Iniquity, too, dammit!)

Speaking of which, I too had been taking an intermission from the evil online inlet of the sea. But then I got a few things on the way to my dock: a probing thing, a vibrating thing, and a thing with 14 LED digits. Coming soon to a post near you...

[0culus]

Here's something some of you might be able to answer: I have a nice set of Teledyne drafting tools. Unfortunately, the foam in their case badly deteriorated and created some kind of chemical reaction with the metal that was touching it, causing pitting. I've removed the instruments and cleaned them as best I can, but I'd like to replace the foam with something modern, but it needs to be easy to cut so the nice little spots for the instruments can be recreated. Any recommendations? It appears the foam in the bottom of the case is about 0.6" (1.524 cm) thick, while the top is about 0.4" (1.016 cm) thick.

[rhb]

Plaster of paris and velvet.

[0culus]

Plaster of paris and velvet.

Interesting....do tell more. Mold with plaster and cover with velvet?

[bitseeker]

You can also use styrofoam sheets and cover with your choice of fabric. A potentially messy and unsatisfactory, but strangely intriguing, option could be foam caulk (white stuff). It's easier to control and expands less than foam insulation (yellow stuff).

I'd go to the art/craft supply store and get some high-density foam.

[beanflying]

Bitch Lives.

mnem
I'm goin' to bed.

Bout time  Yes I am a biatch .....

Enjoy the speediness.

[Cubdriver]

Yep, that's how four Nixie counters ended up finding their way to my lab. Beware!

Only FOUR?     

Slacker!    

-Pat

[mnementh]

Who saw THAT coming...? *raises hand*

mnem
 

[Kosmic]

You could also use freeze spray. But it tend to leave water all over the place.

To find shorts, I had some success using y 34401a in ohms mode.

Yeh, the advantage with the fluid method is that it is far quicker to locate without having to isolate one end of each part, find the dry spot, and that is where the heat is, jackpot.

I don't isolate anything. Just connect the lo terminal of the multimeter to ground and use the hi terminal to probe following the rail path. The point where the resistance is the lowest is usually really close to the short you are looking for.

[bitseeker]

Yep, that's how four Nixie counters ended up finding their way to my lab. Beware!

Only FOUR?     

Slacker!    

LOL! Counters started much later than more voluminous collections such as DMMs.

[Cubdriver]

Yep, that's how four Nixie counters ended up finding their way to my lab. Beware!

Only FOUR?     

Slacker!    

LOL! Counters started much later than more voluminous collections such as DMMs.

I'm afraid to count my counters.   

[bitseeker]

Yes, an advantage of having only four.

[Cubdriver]

Yes, an advantage of having only four.

Touché!   

-Pat