Test Equipment Anonymous (TEA) group therapy thread

[worsthorse]

Within 0.3mV of one another. Not bad. One of them had a cal sticker from 1995 and based on the previous owner's remarks, that's probably the last time they were calibrated.

Now, off to search the forums and see what other folks have done with these things. And though that way lies madness, I caught myself thinking, "I wonder if I should look for a calibration source.

Very nice find, wch. You got one of each: early- and late-model. Packaging-wise, I prefer the early ones.

As for what others have done with the 3478A, check out:

https://www.eevblog.com/forum/projects/project-extending-hp3478a-functionality/

and

https://www.eevblog.com/forum/testgear/hp-3478a-rom-modification-relative-mode/

Thanks for the pointers. I have been digging through various threads but I missed these two.  Yes, one of each. The old one flashes the GPIB address on self test complete, the new one, "self test".  I am going to give them both a good cleaning while I read through the service manual and the forums here and come up with a rehab plan.

Somewhere along the way, I seem to have transformed from the guy looking for a few pieces of test gear to use in building RF stuff to, umm, some other sort.   

[bitseeker]

That'd be the TEA sort... 

[Brumby]

Yea.

A month ago I never thought a GPSDO would be on my wish list.  Now it's on my needs list.


This stuff changes you in ways you could never have predicted.

[beanflying]

Freqnut, Voltnut & Timenut are all tied together and you tell yourself you need more than one addiction to keep the other working better and then you need better to prove your better was actually better.

It is having a strawman argument with yourself and losing 

[Cubdriver]

C'mon in - the water's fine.   

-Pat

[Inverted18650]

Freqnut, Voltnut & Timenut are all tied together and you tell yourself you need more than one addiction to keep the other working better and then you need better to prove your better was actually better.

It is having a strawman argument with yourself and losing 

 

[mnementh]

Finally got a few minutes to dredge the thread and do some proper replies... wow this thing moves fast!

@mnem / med6753 / bitseeker: taaaaaaaants!

@specmaster / @mnem: had a look at the T12. Looks like the tip went short and took the MOSFET with it. MOSFET shorted gate to drain now. Fixable at least! Not too happy about the failure mode. It had a 5A auto fuse in line with it but the MOSFET is clearly a faster fuse by far.

@mnementh: Lego Movie has to be one of the best films ever if you ask me. I may actually go and see Lego Movie 2 this week (on my own)

TAAAAAAAANTS!!! right back atcha dude! The "Battle cry of the TEA Republic"...! 

Heh! Not EVEN CLOSE to 48 hours! 

"Lego Movie" is quite possibly some of the best acerbic commentary on western culture (and/or the lack thereof) since Monty Python. Right up there with Gilliam and Adams. I watch it with my son whenever he'll let me. LM II is one of our top candidates for "Family Movie Time" over spring break.

@tggzzz: on dune ... Dune cannot be compared to Farage. Talking of which, some nice Farage wallpaper here: https://imgur.com/a/GHVQ87Q

Successful in his previous expoits, so he has now moved on to similarly successful exploits on a larger state. Yes, I do mean "exploits"

But, yes, there is a direct comparison between Farrago and Dune-the-Movie-1984. OTOH, the first and third books were good, and the later miniseries was tolerable.

Speaking as a longtime fan of the original Scifi masterpiece, I saw 1984's Dune as doomed from the outset. Trying to boil a story of that magnitude... with so many literal and literary worlds so tightly interwoven with such detail... down to a single 2 hour release was a failure of Hollywood itself, not the poor people given such a Herculean task. There were moments of true brilliance... but like Shymalan's "Last Airbender", there wasn't time for much of any substance or storytelling, only a sequence of striking visuals and intense but brief scenes that would only make sense to someone who knew the original works intimately. I loved Stewart's Gurney Halleck. Loved Sting's manic Feyd. Even loved Brad Dourif's De Vries and Kenneth McMillin's sociopathic Harkonnen.

Dino De Laurentiis chose Lynch well; but unfortunately, they were up against '80s Wall Street money people from pretty much day one. At first he thought he was doing a two parter... which he could see was a massive task but felt was possible. By the time Hollywood production was done with it, even he couldn't recognize it and he tried to take his name off it. The "Extended cuts" later sold as DVDs and aired on TV all credited Alan Smithee. 

Dune is another of those stories like Tolkein's Fellowship Trilogy... a massive work, deserving... requiring... epic storytelling and moviemaking. The later miniseries with Hurt was the proof that Lynch was right; to tell this story needs the Peter Jackson epic series treatment and nothing less.

For those reasons, Lynch's Dune is still one of my favorites... I see it as a flawed but brilliant work; one which was murdered by the money people.

mnem
*Huggles his 189 close* Nooooo! Back! Back you fiends! Back to the rabbithole depths that spawned you!!!

[Inverted18650]

  Love you guys & gals, hope your stacking your carts and enjoying Test Gear Addiction!

[Brumby]

GPSDO... GPSDO... GPSDO...



Oh hell ... does it never end?!!!

[0culus]

GPSDO... GPSDO... GPSDO...



Oh hell ... does it never end?!!!

Haha, me too...I'm thinking ahead to install it in my new lab when I move.

A bit of bad news though, I think the CRT in the display section I got with the 66A doesn't have a huge amount of life left. It abruptly lost a ton of intensity today while I was exercising it. I was able to trim out the problem (mostly) with the adjustments on the A1A2 amplifier board, but unfortunately this probably means the writing is on the wall for it in the nearer future than I hoped.

[URI]

GPSDO... GPSDO... GPSDO...



Oh hell ... does it never end?!!!

It'll get better for you when you get at least one..  and a decent antenna       

[Brumby]

It'll get better for you when you get at least one..

 

[Specmaster]

I finally picked up the two HP 3478A meters I found on CL. I didn't need the HP power supply but I bought it, too, because I didn't really need two more DVMs either, right?  I wasn't able to do much more than plug them in to see if they passed the self test before I brought them home but I got them for a good enough price that it was worth the chance.



Within 0.3mV of one another. Not bad. One of them had a cal sticker from 1995 and based on the previous owner's remarks, that's probably the last time they were calibrated.

Now, off to search the forums and see what other folks have done with these things. And though that way lies madness, I caught myself thinking, "I wonder if I should look for a calibration source.

If you have the manual for them you will see that this model is capable of being calibrated by you fairly easily as it is done via the front buttons. When I got mine I checked the calibration and although it was years since it was last done, it was still withing the parameters. I then decided to replace the ram battery as it was also very old and in doing so I accidently managed to ground the supply to the ram chip so all the calibrations settings were lost.

I got a price from RS for recalibration and sent it off expecting it to be returned within 3 to 5 days all done, On day 7 I phoned only to discover they were struggling as they had no idea how to do it so I had to research the software package and hardware required and they told me that they had that but could not get it to calibrate but would try again. After 2 weeks they gave up and recommended that I should source another meter as it was beyond economic repair and that they would return the meter to me.

Upon receipt of the meter I read the manual and decided to have a go at calibrating it myself and in a couple of hours it was back in calibration and within the specification tolerances. That was some months ago and it is today still in calibration. The manual refers to 2 methods, the first is software driven with the use of calibrators  etc and the 2nd is manually via the front push buttons and known values for each of its ranges.

[med6753]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

[bd139]

Finally got a few minutes to dredge the thread and do some proper replies... wow this thing moves fast!

@mnem / med6753 / bitseeker: taaaaaaaants!

@specmaster / @mnem: had a look at the T12. Looks like the tip went short and took the MOSFET with it. MOSFET shorted gate to drain now. Fixable at least! Not too happy about the failure mode. It had a 5A auto fuse in line with it but the MOSFET is clearly a faster fuse by far.

@mnementh: Lego Movie has to be one of the best films ever if you ask me. I may actually go and see Lego Movie 2 this week (on my own)

TAAAAAAAANTS!!! right back atcha dude! The "Battle cry of the TEA Republic"...! 

Heh! Not EVEN CLOSE to 48 hours! 

"Lego Movie" is quite possibly some of the best acerbic commentary on western culture (and/or the lack thereof) since Monty Python. Right up there with Gilliam and Adams. I watch it with my son whenever he'll let me. LM II is one of our top candidates for "Family Movie Time" over spring break.

@tggzzz: on dune ... Dune cannot be compared to Farage. Talking of which, some nice Farage wallpaper here: https://imgur.com/a/GHVQ87Q

Successful in his previous expoits, so he has now moved on to similarly successful exploits on a larger state. Yes, I do mean "exploits"

But, yes, there is a direct comparison between Farrago and Dune-the-Movie-1984. OTOH, the first and third books were good, and the later miniseries was tolerable.

Speaking as a longtime fan of the original Scifi masterpiece, I saw 1984's Dune as doomed from the outset. Trying to boil a story of that magnitude... with so many literal and literary worlds so tightly interwoven with such detail... down to a single 2 hour release was a failure of Hollywood itself, not the poor people given such a Herculean task. There were moments of true brilliance... but like Shymalan's "Last Airbender", there wasn't time for much of any substance or storytelling, only a sequence of striking visuals and intense but brief scenes that would only make sense to someone who knew the original works intimately. I loved Stewart's Gurney Halleck. Loved Sting's manic Feyd. Even loved Brad Dourif's De Vries and Kenneth McMillin's sociopathic Harkonnen.

Dino De Laurentiis chose Lynch well; but unfortunately, they were up against '80s Wall Street money people from pretty much day one. At first he thought he was doing a two parter... which he could see was a massive task but felt was possible. By the time Hollywood production was done with it, even he couldn't recognize it and he tried to take his name off it. The "Extended cuts" later sold as DVDs and aired on TV all credited Alan Smithee. 

Dune is another of those stories like Tolkein's Fellowship Trilogy... a massive work, deserving... requiring... epic storytelling and moviemaking. The later miniseries with Hurt was the proof that Lynch was right; to tell this story needs the Peter Jackson epic series treatment and nothing less.

For those reasons, Lynch's Dune is still one of my favorites... I see it as a flawed but brilliant work; one which was murdered by the money people.

mnem
*Huggles his 189 close* Nooooo! Back! Back you fiends! Back to the rabbithole depths that spawned you!!!

Totally agree on all points. It was difficult to cram it in that. I understand there was nearly 6 hours of footage and they cut it down to just over 2 for cinema audiences and then re-cut to 3 hours for TV purposes.  I'd watch the full thing!

[bd139]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

There are a couple of "print my thing" links on thingiverse. Never tried one but surely they'd be cheaper than the ebay sellers who rpobably use that.

[med6753]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

There are a couple of "print my thing" links on thingiverse. Never tried one but surely they'd be cheaper than the ebay sellers who rpobably use that.

Oh OK, didn't realize that. I'll check it out. 

[beanflying]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

There are a couple of "print my thing" links on thingiverse. Never tried one but surely they'd be cheaper than the ebay sellers who rpobably use that.

Oh OK, didn't realize that. I'll check it out. 

I may need to change my cataloguing system if it gets to unwieldy 

Plenty of us with Printers. The plastic costs are minimal so offer some postage/graft and corruption should get it done in house. Bit expensive from my end for post and would be nearly $20 USD. I work for BEER   

[tggzzz]

And though that way lies madness, I caught myself thinking, "I wonder if I should look for a calibration source.

Don't forget the next question: "has the calibration source been aged for long enough?". Basically, ignore an "initial accuracy" spec, but pay attention to per 90days, per year and per decade specs

Then there are more questions that will niggle at the back of your mind.

[tggzzz]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

Shapeways prices, per foot:
Professional Plastic £17.36
Versatile Plastic £7.43
Fine Detail Plastic £20.41
Steel £47.06
Aluminum £101.03
Bronze £199.30
Gold Plated Brass £294.97
Brass £199.30
Rhodium Plated Brass £294.97
Silver £398.61
Gold £4,252.18
Platinum £14,637.54

DirtyPCBs SLA $45 for all 4

[mnementh]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

There are a couple of "print my thing" links on thingiverse. Never tried one but surely they'd be cheaper than the ebay sellers who rpobably use that.

Oh OK, didn't realize that. I'll check it out. 

I may need to change my cataloguing system if it gets to unwieldy 

Plenty of us with Printers. The plastic costs are minimal so offer some postage/graft and corruption should get it done in house. Bit expensive from my end for post and would be nearly $20 USD. I work for BEER   

Pretty sure I can do this if PLA is strong enough. I'm thinking 1.5mm walls and 40% infill, printed on the flat as shown. Whaddayoothink b?

I'm pretty sure PLA can handle typical loading in compression plane; what I'm worried about is breaking that first fin off the "bottom" two feet with lateral loading when somebody tries to lever the scope up onto its feet from horizontal by lifting up on the bail.

med, I can do this in Lord Vader Black, Purple Nurple, or Meh Grey. Choose wisely.

mnem
*poit!*

[tggzzz]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

There are a couple of "print my thing" links on thingiverse. Never tried one but surely they'd be cheaper than the ebay sellers who rpobably use that.

Oh OK, didn't realize that. I'll check it out. 

I may need to change my cataloguing system if it gets to unwieldy 

Plenty of us with Printers. The plastic costs are minimal so offer some postage/graft and corruption should get it done in house. Bit expensive from my end for post and would be nearly $20 USD. I work for BEER   

Pretty sure I can do this if PLA is strong enough. I'm thinking 1.5mm walls and 40% infill, printed on the flat as shown. Whaddayoothink b?

I'm pretty sure PLA can handle typical loading in compression plane; what I'm worried about is breaking that first fin off the "bottom" two feet with lateral loading when somebody tries to lever the scope up onto its feet from horizontal by lifting up on the bail.

Is the part likely to split/tear along joins between layers?

Forces will be the obvious w.r.t. the floor, plus cables force squeezed into the gaps when cable is stored, plus cables pulling feet towards the centreline of the instrument.

[mnementh]

This is from beanflying's thread on replacement feet and stuff. Who would be willing to print me up 4 of these? Needed for the 475A. Of course I'll pay. Ebay sellers want $25 USD which is a bit excessive.

https://www.thingiverse.com/thing:1410827

Pretty sure I can do this if PLA is strong enough. I'm thinking 1.5mm walls and 40% infill, printed on the flat as shown. Whaddayoothink b?

I'm pretty sure PLA can handle typical loading in compression plane; what I'm worried about is breaking that first fin off the "bottom" two feet with lateral loading when somebody tries to lever the scope up onto its feet from horizontal by lifting up on the bail.

Is the part likely to split/tear along joins between layers?

Forces will be the obvious w.r.t. the floor, plus cables force squeezed into the gaps when cable is stored, plus cables pulling feet towards the centreline of the instrument.

Layer adhesion strength is my concern here. This is why I was asking b for a second opinion on my "finger in the air estimate" slicer settings.

mnem
The moose is loose. Uhh... tighten him up a little, willya?

[nixiefreqq]

GPSDO... GPSDO... GPSDO...



Oh hell ... does it never end?!!!

Haha, me too...I'm thinking ahead to install it in my new lab when I move.

A bit of bad news though, I think the CRT in the display section I got with the 66A doesn't have a huge amount of life left. It abruptly lost a ton of intensity today while I was exercising it. I was able to trim out the problem (mostly) with the adjustments on the A1A2 amplifier board, but unfortunately this probably means the writing is on the wall for it in the nearer future than I hoped.

don't overlook used telco gps timing modules.

the down side with them is that they usually require 24 or 48 volt supplies, and they often have smb inputs/outputs.

BUT lady heather discipline software talks to this one just fine via rs232, and it is built like a tank. (like most old telco stuff).

sometimes you can find them cheap because they look odd to folks more familiar with radio equipment (vs central office gear). 

[bd139]

I'm considering doing that actually. I've seen some Agilent/HP GPSDO units appear on auctions on and off here as well. Not sure if they're any good these days though.

Got itchy spendy fingers at the moment. Managed to shift some radio gear already. Looking at LCR meters. Any suggestions welcome. I'm sure I'm asking in the right place 

Looked at Peak LCR45 which is about right but the damn thing doesn't do ESR. You have to buy another box to do ESR.