Test Equipment Anonymous (TEA) group therapy thread

[beanflying]

Spreading my current project pollution here rather than in the what did I buy... thread.

MK II Fume extractor, smaller, stronger, simpler design, less parts and laser cut a filter sample which works great. Also split the rear fan cover to get better material use/sheet (jigsaw feature  ).

Any thoughts on what would a flatpack kit with everything (including hardware) bar the 120mm fan be worth delivered to your door? Postage with 4-6 filters is just on $7 USD anywhere on the planet.

I'm the original cheap bastahd, and I'd buy that kit without thinking twice if I saw it at Fry's or MicroCenter in the $10-12 range. The more filters, the quicker I'd snatch it up. IME, that means normal, more "consumer-ey" minded folks would probably go as high as $15, maybe even $20; especially if you remind them that they're saving $40-50 over the HAKKO by DIYing.

The problem you're going to have with those sorts is... you'll have to write up a short treatise on fan selection. Sure as shootin', even in THIS relatively well-educated market on eevBlog, you'll get some yo-yo who puts a low-speed Noctua in there and blames you because it doesn't suck. 

A couple suggestions...

1) The center medallion area on the back seems a bit large; at a guess approx 55mm. Looking at my collection of 120mm fans, only one AC-powered unit has a motor that wide; the rest are 40-45mm. Whether it's so or not, that large medallion area APPEARS to block some airflow, and might cost you some potential sales.

2) You could also offer an "Option" of a strip of 12V white LEDs to go on the front inside edge of the hood; that thing will be well positioned to shine light right on the work pretty much any time it is in use. 

mnem
*Scurries off to sign up for 2 kits*

The rear in MK I was open so I was lazy but a shrink to 45mm would still work, the motor I had was 60mm across. With longer screws it will obviously take wider motors too if people don't mind the rear penis guard sitting out from the body.

LED strips people could do their own even RGB for that Disco Gamer look  Easily room for two runs of 6 and passing the wires around the motors rounded corner would be easy.

On pricing I still haven't done a full costing for it but more likely just over $20USD with the option of Eucalyptus Hardwood Ply for $3-4 more. It needs to stay under 250g and 20mm thick to keep the postage sensible worldwide so the hardwood might push that.

[mnementh]

As soon as I have a place for you to ship them, I'll take 2. 

mnem

[tggzzz]

We have a tendency to be hillbilly bodgers here. The metrology mob are the purists

It is easy and cheap to ensure all your equipment agrees on a value. It is trickier to ensure they agree in a week's time. It is difficult and expensive to ensure they agree with other people's equipment.

But, I'm a part of this metrology mob. A very very tiny one ...   
 

I'm just a wannabe voltnut who has been able to afford some old equipment of dubious accuracy, some of which he has no clue how to use.

The best "face" I can put on the situation is that at least I know (some of) my inadequacies

[worsthorse]

As soon as I have a place for you to ship them, I'll take 2. 

mnem

I'm in, fancified wood or not!  Nice work.

[worsthorse]

I finished cleaning up, calibrating, and testing the Heathkit voltage reference. It is ready to head to ebay.  Then I started thinking...

I have a Fluke 8800, Keithley 199, Keithley 197, B+K something or other, and at least one more HP DMM on the shelf. I plan on testing them, doing whatever simple calibration I can, makin' them pretty and selling them (Which will leave me with three 5.5 digit DMMs and three lesser one) to free up space and generate cash. So I look at the EU80-A and think, why don't I keep the that and use it as my voltage reference for calibrating these meters?

Great idea, right? So now the Heathkit is on my test bench, as is the 8800. I will keep the voltage reference long enough to check these meters and then sell it.

And we have another example why nothing ever seems to make it from my "sell" shelf to ebay.    

Are you sure that reference is accurate and stable enough to check 5.5 digit DMM's? Based upon what I saw plus a quick check of it's specs I would think not but that's just me. 

No it is not, though it is reasonably stable if I let it warm up for a couple of hours and set the voltage by measuring it with my known good DMM. I just want to be able to represent that they work on all ranges reasonably well. I won't suggest that I have calibrated them.  I will take them to the next hamfest or offer them on a couple of the test equipment lists. About ebay I am not so sure. Certainly not at auction. I am tempted to sell them as-is just so I limit my interactions with PITA buyers.

Stability is more subtle than that.

If you then it off and on again after 1/10/1000seconds, does the value return to the same?
How about popcorn noise? One of my old professional sources has 1.5ppm popcorn noise
And then there's simple drift.

Welcome to the rabbit hole.

   but, my friend, subtlety is not my strong suit...

You are, of course, correct. Using the EU80A results in, at best, slide rule accuracy. But if these DMMs read within a couple of percent of expected value on all scales, I can say, honestly, that they are in good working order and that's all I want to be able to do. For this project, I am matching the precision of the process to the desired goal.

And I shamefacedly admit that this approach is antithetical to everything we stand for in this thread. 

We have a tendency to be hillbilly bodgers here. The metrology mob are the purists

It is easy and cheap to ensure all your equipment agrees on a value. It is trickier to ensure they agree in a week's time. It is difficult and expensive to ensure they agree with other people's equipment.

You are right on all counts. I am not doing simple calibration in the sense used by metrology fans, let alone traceable calibration. I just want to be sure that these meters work reasonably well throughout their operating range, reasonably well being defined as operating within a couple of percent of the value of a measured voltage reference at a given point in time. And if I repeat that process a week or three from now, I would want to see the new reading in that couple of percent range. For me, that's "working" in a practical sense.

I think that it is safe to say that, outside of our weird little bubble, most hobbyists don't have three five point five digit DMMs on their bench, let alone three that must agree with one another over time and to a standard. Those that do probably aren't going to be interested in buying any of my DMMs ever!

[mnementh]

For 30 years, my personal "reference standard"... or maybe more my personal "reality check" whenever I saw something that didn't make sense with another instrument... was a Fluke 87 that had been factory Cal'd. By Philips. For use in a Philips Lighting factory. In my old age I've "upgraded" to a salvage 189, which has been untouched (aside from repairing fugly battery compartment) since manufacture and tests dead-nuts against a cheap AD584LH voltage reference (eBay auction: #311498494419) and a collection of 0.1% resistors. I'm also willing to trust in its absolute accuracy the same way (at least until I get around to getting a DMMCheck ), even as I have a similarly trusted 3478A on the bench.

mnem
Life is much easier once you've come to terms with your own ignorance. In a way, it's the only path to growth.

[tggzzz]

I just want to be sure that these meters work reasonably well throughout their operating range, reasonably well being defined as operating within a couple of percent of the value of a measured voltage reference at a given point in time. And if I repeat that process a week or three from now, I would want to see the new reading in that couple of percent range.

... and so it begins

Do I need an 8 digit DVM? Hell no.
Is it fun? Hell yes. (Mostly)
Does it keep me off the streets? Hell yes. (Until I go and collect the next precious treasure)

[mnementh]

"Memo to self: do not become a voltnut."

mnem
 

[Kosmic]

Nice knobs. No way that you could send me the "Sync. Selector" knob?    

It's so much more than knobs, it's a 7.6 GHz vacuum tube frequency generator. Brains and beauty, It's eyes are right there and all you choose to look at are it's knobs, shame on you.... shame!

The answers is maybe.... if I can find a look alike close enough to suit me then maybe. Wouldn't be cheap though.

 

Even though I'm a German you shouldn't take me too serious. Sometimes I'm trying to make a joke (and fail) 

Honestly, I've set a search in ebay on this kind of knob, hoping, that sometimes one will show up with
the right diameter (25mm from peak-to-peak, 20mm the outer ring, the diameter for the drive shaft is 6.25mm)

Or I'll do it the med-way, finding a parts-mule.
Btw, it is a nice generator, would be a crime to rip off a knob.   

Edit:
Maybe this one would fit:
https://www.ebay.com/itm/Hewlett-Packard-HP-Model-202H-FM-AM-Signal-Generator-8-KNOB-LOT/303155915017



What's the size of a quarter anyway? 

BU508A, I got this one if you want. Diameter is 24.10mm and shaft is 6.40mm

[worsthorse]

I just want to be sure that these meters work reasonably well throughout their operating range, reasonably well being defined as operating within a couple of percent of the value of a measured voltage reference at a given point in time. And if I repeat that process a week or three from now, I would want to see the new reading in that couple of percent range.

... and so it begins

Do I need an 8 digit DVM? Hell no.
Is it fun? Hell yes. (Mostly)
Does it keep me off the streets? Hell yes. (Until I go and collect the next precious treasure)

Well, I did mention that even if I sell four DMMs, I will have at least three of five point five models left, not to mention three four digit devices.   

Like a lot of folks here, I am fascinated by precision and stability, whether of time, voltage, frequency, or temperature. It is such an interesting set of problems. So far though, I have managed to satisfy my fascination mostly by watching other people pour piles of money into eight digit meters, precision calibration sources and the like. 

[Brumby]

I was a little disappointed that no EE based solutions were offered.

As a first thought ... how about an induction heating system to cook the cambium layer?  A sort of electromagnetic ring barking.

That would keep the subject on topic 

Quite, given the origins of this forum I'm frankly astonished that no-one has yet suggested attaching a lightning conductor to the top of the tree and waiting for nature and science to take its course. 1.21GW will kill most things, I expect...

I like it.  A bit random on the time frame - but it might be worth implementing while more definite options are being explored.   

[bitseeker]

Spreading my current project pollution here rather than in the what did I buy... thread.

MK II Fume extractor, smaller, stronger, simpler design, less parts and laser cut a filter sample which works great. Also split the rear fan cover to get better material use/sheet (jigsaw feature  ).

MK II looks great. I like it more than MK I.

2) You could also offer an "Option" of a strip of 12V white LEDs to go on the front inside edge of the hood; that thing will be well positioned to shine light right on the work pretty much any time it is in use. 

That's a good idea.

[bitseeker]

I finished cleaning up, calibrating, and testing the Heathkit voltage reference. It is ready to head to ebay.  Then I started thinking...

I have a Fluke 8800, Keithley 199, Keithley 197, B+K something or other, and at least one more HP DMM on the shelf. I plan on testing them, doing whatever simple calibration I can, makin' them pretty and selling them (Which will leave me with three 5.5 digit DMMs and three lesser one) to free up space and generate cash. So I look at the EU80-A and think, why don't I keep the that and use it as my voltage reference for calibrating these meters?

Great idea, right? So now the Heathkit is on my test bench, as is the 8800. I will keep the voltage reference long enough to check these meters and then sell it.

And we have another example why nothing ever seems to make it from my "sell" shelf to ebay.    

I hear ya. I've got some stuff I need to shift, too. Need to make space, but it takes time and I have less time than space at the moment.

And then, oops, I scored a Tektronix 191. Oh, well.

[bitseeker]

Here's what I'm going to do short term. I'm going to run with this 485. Take the volts/div knobs off mine and clean this one up. But I'm NOT going to scrap mine and just use it for parts. I am absolutely determined to find out why it won't trigger. Now that I have a working unit I can put them side-by-side and figure out what's wrong. But to do that I have to completely clean off one of the benches so I can fit them together. So long term that's what I'll do after some other pending projects are done.

Sounds like a good plan to me, med. Congrats on the turn of events. Gotta go with the flow.

[Black Phoenix]

As soon as I have a place for you to ship them, I'll take 2. 

mnem

1 here shipped to Hong Kong please. 

[bitseeker]

A quick heads-up passed on to me by eevBlog member Johnboy :

SMC has the part # 200-0633-01/214-0531-01/348-0013-00/252-0571-00  front cover used on Tek 453/454 and other series scopes for $20. It's about 3/4 of the way down the page; Stock #: TEKMECH67 . He bought one and they still have it up, so odds are they have more than one. I know a lot of you hate supporting the strip-miners out there, but I feel this is important enough to pass on in here; we're talking about protecting the scope you've already spent so much time on.

PS: Yes, I've already explained to him how a lot of us feel about the strip-merchants out there; no need to beleaguer the guy. 

Hmm, I see he has the little lever knob for my 454. But do I get one from him or wait for another old Tek to come along that has that knob and so much more? I should have a spare 454 to keep mine going, right?

As for the cover, the 454 manual lists a different part number (200-0633-02 instead of 200-0633-01) and indicates that it's only for the 454.

[neo]

Nice knobs. No way that you could send me the "Sync. Selector" knob?    

It's so much more than knobs, it's a 7.6 GHz vacuum tube frequency generator. Brains and beauty, It's eyes are right there and all you choose to look at are it's knobs, shame on you.... shame!

The answers is maybe.... if I can find a look alike close enough to suit me then maybe. Wouldn't be cheap though.

 

Even though I'm a German you shouldn't take me too serious. Sometimes I'm trying to make a joke (and fail) 

Honestly, I've set a search in ebay on this kind of knob, hoping, that sometimes one will show up with
the right diameter (25mm from peak-to-peak, 20mm the outer ring, the diameter for the drive shaft is 6.25mm)

Or I'll do it the med-way, finding a parts-mule.
Btw, it is a nice generator, would be a crime to rip off a knob.   

Edit:
Maybe this one would fit:

-snip-

What's the size of a quarter anyway? 

The comment below the line was the set up for a joke. You were meant to ask how much, then i give some ridiculous monetary value or perhaps even your soul. Also a quarter is 24.26mm

[URI]

ebay global shipping program rant:
I mentioned it in my last posting:
Pitney Bowes and/or Hermes managed to deliver a 81103 signal board (the heart of the HP 8110A Pulse Generator signalwise) I won for $10 on ebay in a way making it useless for me because of the damage that happened to it due to poor packaging. 






I have to admit that the cardboard package was really heavily deformed on one corner.. but with nearly no clearance inside the box the PCB had no chance. 

After receiving several items through ebay's global shipping program my experience is mostly bad.
All except one piece of three 8110A chassis/devices and two 81103A signal boards have been damaged through shipping.
I have evidence of poor repackaging in one case where seller could show with own photos that pitney bowes had left padding material when repackaging. 
I don't get it. Who needs them if it's safer to not use the gsp..?
Got full refund meanwhile. 

Money back but the board is electronic waste now.   

[beanflying]

Found some ancient mega flux cored solder to test. Running about 1.8W of fan in the video, some parallax on the ruler second suck of the sav was more like 120mm. Works at 1W but restricted to more like 100mm

What goes in doesn't seem to come out either 

[med6753]

You can't really blame the shipping company for the damage when the idiot who originally packed it did a poor job. 

Example of excellent packaging: the 485 I just received. At least 5 to 6 inches of expandable foam surrounding the entire scope in a huge box. That amount of packaging would have survived a trip around the world but only had to ship from New Jersey to New York. 

[URI]

You can't really blame the shipping company for the damage when the idiot who originally packed it did a poor job. 

Yep, you're right. But I stated indeed that the damage happened because of poor packaging -not enough clearance and padding inside the cardbox package..

Example of excellent packaging: the 485 I just received. At least 5 to 6 inches of expandable foam surrounding the entire scope in a huge box. That amount of packaging would have survived a trip around the world but only had to ship from New Jersey to New York. 

Though ranting about shipping damages from time to time I'm glad most of my TE came from over the pond safely and intact and I did indeed mentioned the good packaging from time to time too.   
For future acquisitions I'll avoid ebay's global shipping program although it's very comfortable to get the item shipped to your door while all customs handling is done for you.

I'll rather fetch my packets at the local customs office undamaged than getting it delivered to my doorstep damaged.

I'll try to make at least one fully functional and intact 8110A from all the damaged parts and perhaps a second one that isn't mechanically perfect but fully functional.

[Specmaster]

I just want to be sure that these meters work reasonably well throughout their operating range, reasonably well being defined as operating within a couple of percent of the value of a measured voltage reference at a given point in time. And if I repeat that process a week or three from now, I would want to see the new reading in that couple of percent range.

... and so it begins

Do I need an 8 digit DVM? Hell no.
Is it fun? Hell yes. (Mostly)
Does it keep me off the streets? Hell yes. (Until I go and collect the next precious treasure)

Well, I did mention that even if I sell four DMMs, I will have at least three of five point five models left, not to mention three four digit devices.   

Like a lot of folks here, I am fascinated by precision and stability, whether of time, voltage, frequency, or temperature. It is such an interesting set of problems. So far though, I have managed to satisfy my fascination mostly by watching other people pour piles of money into eight digit meters, precision calibration sources and the like.

I agree with mnem here, I do the much same testing with a eBay voltage reference and 0.1% resistors, a little Mastech calibrator I snagged for a song, new in a nice carry case that provides DC volts and current uptp 24v 24ma and an oscilloscope calibrator that also provides DC volts upto 100v. I use these items to check my meters of upto 6.5 digits & in all cases they all agree upto the last digit (+/-2counts) & last 2 digits on the 6.5 meters (+/-10counts) & as a last sanity count check against a factory calibrated Brymen BM867. When it comes to selling them on, photograph them working connected to a reference source and quote what ref is, ie. 10v and let the buyer decide if its good enough accuracy for them. So far I have always gotten back far more then I paid for them using this method.

Sent from my POT-LX1 using Tapatalk

[Specmaster]

You can't really blame the shipping company for the damage when the idiot who originally packed it did a poor job. 

Yep, you're right. But I stated indeed that the damage happened because of poor packaging -not enough clearance and padding inside the cardbox package..

Example of excellent packaging: the 485 I just received. At least 5 to 6 inches of expandable foam surrounding the entire scope in a huge box. That amount of packaging would have survived a trip around the world but only had to ship from New Jersey to New York. 

Though ranting about shipping damages from time to time I'm glad most of my TE came from over the pond safely and intact and I did indeed mentioned the good packaging from time to time too.   
For future acquisitions I'll avoid ebay's global shipping program although it's very comfortable to get the item shipped to your door while all customs handling is done for you.

I'll rather fetch my packets at the local customs office undamaged than getting it delivered to my doorstep damaged.

I'll try to make at least one fully functional and intact 8110A from all the damaged parts and perhaps a second one that isn't mechanically perfect but fully functional.

Personally I have got many items that were shipped using the GSP and everything arrived just fine. I also seem to attract a lot of overseas buyers so use GSP for shipping and only issue on one radio which the buyer claimed arrived scratched. I had photographed it from all angles during the packing, and wrapped it in 4 layers of bubble wrap. Placed about 3" of expanded foam all round the radio on all sides in the outer carton and used strong gaffer tape round the carton, there was no way that scratch happened in transit.

I told the buyer this and said that I had supplied the photos etc to eBay and told him to claim through eBay as GSP assume all responsibility for the item once they receive at their depot. I never heard anything further and I got good feedback.

Sent from my POT-LX1 using Tapatalk

[bd139]

I’ve had about six things through GSP and half the packaging was munted and poorly packed. Fortunately they weren’t fragile items!

I actually skipped a Heathkit HW-7 the other day because it was GSP

[tggzzz]

"Memo to self: do not become a voltnut."

I explicitly tried that technique, with insufficient success

In my case some functional 70yo saturated Weston Cells were the gateway to hell.