Test Equipment Anonymous (TEA) group therapy thread

[Inverted18650]

I also have a set that has the "special" screwheads that Apple invented to keep people out of their hardware...just in case. 

scheisse bro, iDeviceguy is my eBay name...I have a coupe sets.

[mnementh]

Don't forget the Reed&Prince!

I've been trying for DECADES to forget them... thanks SO much. 

   Just the tips.

Pffft. I keep more than that in my drill bag. We won't talk about the collection of 1/4", 3/8" & 1/2" drive... Or the box full of iToolz. 

In Other News...



DollHouse hinges arrived for the front door on my computer case.
SO-O-O-O-O tiny... 

mnem
Yes, you may touch it.

[Cubdriver]

Took apart the 8568B RF section front panel to get to the attenuator. Remarkably easy, actually, except that when I reassembled it I forgot to plug in the little plug that powers and controls the attenuator.  Cue unstacking the display and taking it down once again to open it up...I got my workout tonight! 

Anyway, I took apart the attenuator and examined it for signs of a major power excursion and could find none. I think it may in fact just be worn out and the contacts are not making good contact with the tiny resistive pads. Perhaps one of the solenoids is weak. A +15 dBm signal is capacitively coupling approximately -61 dBm through the attenuator from 0-30 dBm attenuation, and correct amplitude from 40-70 dBm attenuation.

Since I have no way to repair such a precision device, I am definitely going to need a new attenuator.

Oculus, you might want to check the HP mailing list (HP-Agilent-Keysight-equipment) on Groups.IO.  Unfortunately I've never paid much attention because it wasn't info I have thus far needed, but I recall discussions over there regarding some HP attenuators having small o-rings that eventually break down and that can be replaced (though they are an odd size - folks have gotten them from Apple Rubber).  I've no idea if your attenuator is one of those so affected, but a search or a post there might elicit some additional information from those who have been there and done that.  It's worth a shot.

FWIW.

-Pat

[Inverted18650]

Those hinges are for the PC case...stoked to see it...and the PFFFT had me rolling!

[Neomys Sapiens]

Today I lost out on a Holt Instruments coaxial shunt kit. Gone on ebay.de for around 200.-€!
Just because, being at my office, I got distracted by work. Silly me!

The Transistor Devices DLP 50-60-1000 arrived today. Nothing shaking, nothing obviously missing.
The red AC power switch feels a bit  ....err, funny.
But I can't power it up right now, because I have to adapterize the strange power input connector.

I might have got it wrong with the two units. The DLP is supposed to be working, the 4Q-supply might be inoperative.

[mnementh]

Those hinges are for the PC case...stoked to see it...and the PFFFT had me rolling!

I may actually have to solder them to bits of metal to make them longer in this application. They're narrow enough to fit in existing slots, but not enough surface area to epoxy in place. 

mnem
Jinkies!!!

[0culus]

Took apart the 8568B RF section front panel to get to the attenuator. Remarkably easy, actually, except that when I reassembled it I forgot to plug in the little plug that powers and controls the attenuator.  Cue unstacking the display and taking it down once again to open it up...I got my workout tonight! 

Anyway, I took apart the attenuator and examined it for signs of a major power excursion and could find none. I think it may in fact just be worn out and the contacts are not making good contact with the tiny resistive pads. Perhaps one of the solenoids is weak. A +15 dBm signal is capacitively coupling approximately -61 dBm through the attenuator from 0-30 dBm attenuation, and correct amplitude from 40-70 dBm attenuation.

Since I have no way to repair such a precision device, I am definitely going to need a new attenuator.

Oculus, you might want to check the HP mailing list (HP-Agilent-Keysight-equipment) on Groups.IO.  Unfortunately I've never paid much attention because it wasn't info I have thus far needed, but I recall discussions over there regarding some HP attenuators having small o-rings that eventually break down and that can be replaced (though they are an odd size - folks have gotten them from Apple Rubber).  I've no idea if your attenuator is one of those so affected, but a search or a post there might elicit some additional information from those who have been there and done that.  It's worth a shot.

FWIW.

-Pat

Thanks for the tip, I'll go check it out.

[Inverted18650]

Those hinges are for the PC case...stoked to see it...and the PFFFT had me rolling!

I may actually have to solder them to bits of metal to make them longer in this application. They're narrow enough to fit in existing slots, but not enough surface area to epoxy in place. 

mnem
Jinkies!!!

Dude you are a next level customization specialist. Above and beyond and with the time and energy you put into this, man...Id like to see what you could do with an infinite budget and a deadline on some crazy spec'd build.

[mnementh]

Psssttt... don't tell anyone, but for me this is just an excuse to use all the toys tools I've collected.

[EDIT]



Oh, when I'm allowed to spend OPM, then I build cars... Like a full-frame VW Beetle with a 460 ford stuffed into the trunk, or a Triumph Spitfire with Paxton-blown Cologne V6 and Getrag 5-speed shoehorned under the stock hood. That does wheelstands in the first 3 gears. 

[/EDIT]

mnem
*ToolDwagon*

[Inverted18650]

Today I lost out on a Holt Instruments coaxial shunt kit. Gone on ebay.de for around 200.-€!
Just because, being at my office, I got distracted by work. Silly me!

The Transistor Devices DLP 50-60-1000 arrived today. Nothing shaking, nothing obviously missing.
The red AC power switch feels a bit  ....err, funny.
But I can't power it up right now, because I have to adapterize the strange power input connector.

I might have got it wrong with the two units. The DLP is supposed to be working, the 4Q-supply might be inoperative.

Where are the pics of the Trans Device UNIT? I love them

[Carl_Smith]

I had one when the ISA bus was a thing. After that I just google the beep codes or swear at it and throw it in the trash

I still have one.  Mine has a flat ribbon cable with an extra 7 segment display on it so you can still see the codes when you can't see the display on the cards.  I even have the book that tells me the error codes for various bioses.  Biosi?  It had its fair use back in the day and I keep it out of a bit of sentimentality.

Mine came with that; I never bothered to install it. I have actually used mine as recently as a couple years ago. I keep it against the day I need to resurrect some prehistoric machine to salvage data. And because I'm a fucking TEAnut, and it's TE. 

I have a couple PCI post cards, and I actually used one a few days ago.

I have an old Pentium 4 system from around 2004 that had some files on it I wanted to copy to a flash drive.  I know I have the files backed up to another drive somewhere but I can't find that drive so I figured I'd just power up the system for the first time in a couple years and copy them off.  System wouldn't power on at all. 

The sensible thing to do at this point would have been to just pull the hard drive out and put hook it up to another system, get my files, and dump the bad PC in the recycling.  After all, its a P4 from 2004.   But I can't resist trying to fix things, especially since I have a horde of old PC parts from that era.

In the end it turns out that after an hour of testing the power supply and plugging and unplugging components thinking one was preventing the power supply from powering up, it turns out the motherboard and processor are toast.

The motherboard has 5 tall electrolytic capacitors right by the processor and everyone is swelled on the end and spewing out their guts.  I feel kind of stupid for not checking that immediately. 

I did a downgrade and replaced the bad 875 board with an good 865 board since that was the best remaining board I had without round-end-capacitors, put in a new processor (I'm guessing the bad caps toasted the processor too) and it's back to working.  The post card actually wasn't that helpful in this case but it did show that something was sucking down one of the power supply rails.

Anyway, that rabbit hole wasted several hours but now I have a working 15 year old PC again.

And use of the post card confirmed that it is worth keeping things like that around. 

[mnementh]

So you're trying to say it has nothing to do with being a TEAnut?   

Who are you trying to convince... me or yourself? 

mnem
I long ago gave up on that one... 

[jlw]

I found the pictures I took when I first opened mine (I'm loathe to just go open it again when I've got this expensive smartphone with a camera to take pictures and an expensive computer with an expensive disk to store those pictures.  Gotta _use_ those things I spent money on....) and there's a very similar grey lump labelled pretty much exactly like yours (slightly higher serial number).  Well, I'll be. I have an OCXO.  It might even be working.  To think that what I spent on this counter amounts to almost nothing.

Started measuring the 1MHz output against a GPSDO-referenced counter for a while now, settling around 999999.7764Hz.  The A.G.C. output on the back measures +0.507320E+01 Volts.  And isn't it nice that all the GPIB stuff is playing nice together and I can cut and paste this stuff without errors creeping in via the ol' eyeball.

Heading through 999999.7786 at +0.507250E+01
And 999999.7803 at +0.507210E+01

Now the question is whether I can tweak it.

[Neomys Sapiens]

Today I lost out on a Holt Instruments coaxial shunt kit. Gone on ebay.de for around 200.-€!
Just because, being at my office, I got distracted by work. Silly me!

The Transistor Devices DLP 50-60-1000 arrived today. Nothing shaking, nothing obviously missing.
The red AC power switch feels a bit  ....err, funny.
But I can't power it up right now, because I have to adapterize the strange power input connector.

I might have got it wrong with the two units. The DLP is supposed to be working, the 4Q-supply might be inoperative.

Where are the pics of the Trans Device UNIT? I love them

Posted one in the 'show your test equipment scores here!' thread. Sometime over the next days I'll un-lid it and maybe I have a camera ready. I'm on a spare computer, some family trouble and, more relevant, still running the same one-man-department routine that makes me think, dream, breathe, s*** ADS-B and MSSR and IS there really a life beyond ICAO Vol.10 Annex 4 and the interference problem and the thermal glitch and the obsolescences and and 
<Crash! Tingle! Moo!>
One shrew down now. 

[beanflying]

Do I win a prize for owning the crustiest, oldest and most useless PC type testcard any other takers?  Darn that 'modern junk' Mnementh you are showing off

This came in the big evilbay box of junk with the RF connectors, probes etc and the two unlisted FREE Weston Standard Cells 

[Inverted18650]

I found the pictures I took when I first opened mine (I'm loathe to just go open it again when I've got this expensive smartphone with a camera to take pictures and an expensive computer with an expensive disk to store those pictures.  Gotta _use_ those things I spent money on....) and there's a very similar grey lump labelled pretty much exactly like yours (slightly higher serial number).  Well, I'll be. I have an OCXO.  It might even be working.  To think that what I spent on this counter amounts to almost nothing.

Started measuring the 1MHz output against a GPSDO-referenced counter for a while now, settling around 999999.7764Hz.  The A.G.C. output on the back measures +0.507320E+01 Volts.  And isn't it nice that all the GPIB stuff is playing nice together and I can cut and paste this stuff without errors creeping in via the ol' eyeball.

Heading through 999999.7786 at +0.507250E+01
And 999999.7803 at +0.507210E+01

Now the question is whether I can tweak it.

Hello and I am stoked your very first post to the forum was here in the T.E.A. thread. WELCOME and tell us all a bit about yourself and your addictions before you hop in with your big numbers and + signs and decimal points.

[mnementh]

   Do I win a prize for owning the crustiest, oldest and most useless PC type testcard any other takers?  Darn that 'modern junk' Mnementh you are showing off

This came in the big evilbay box of junk with the RF connectors, probes etc and the two unlisted FREE Weston Standard Cells 

Old & crusty it may be, but not useless. I work with RS232-based networking on a regular basis; many of your big chain hotels & motels still use it to connect their frontend registers/reservations terminals to the servers in back. You'll also still see the occasional dialup connection for remote management, and of course even with WebEx as the current standard, you still have RS232 rollovers and DB9 crossovers used as local connection for Switch, Router, Gateway, VPN and Firewall devices.

I'd scrub that bad girl with alcohol, scrounge up a couple DB9-DB25 dongles, and put 'er to work.

mnem
"Someday, my prints will come..."

[beanflying]

Completed projects. Both the 190VDC reference and the 190mv, 1.9V, and 19V reference.



The updated and final schematic for the 190mv, 1.9V, 19V reference.



The next challenge: a stable 500VDC reference. Will start some design/build work this week.

Other news: The Fluke 8810A is on the UPS truck for delivery.

This will teach @med not to start a 'proper thread' for his Vref project.    Way back weeks and weeks ago I went searching to find this

Just running some numbers today on a Hamon divider I am building and looking at output loading by switching from 10Meg meters to 10Gohms+ meters. The answer is it does matter in particular at the 100:1 range divider range. I have included a screen cap of the spreadsheet I am playing with to give you an idea and the resistor values. Block one is a 10Gohm block 2 and 3 are for 10Meg with three getting a tweak to 10.01V so I can sort out what sort of range I need the input voltage to vary so I can use it as a transfer standard.

What this means is just make sure with your numbers that the Siglent matches the input impedance of what you are comparing or trying to transfer to in your Rabbit Hole much as it will only effect the LSD but it matters

[mnementh]

So close... I can tell the print is less than an hour away, but I'm falling asleep on my keyboarqe['r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r'r
b\,tb
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b\,tb
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b\,tb
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b\,t
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b\,trdddd,.................

mnem
ZZZzzzZZZzzz...

[VK5RC]

DANGER WILL ROBINSON
NIXIE PORN AHEAD
Doing my monthly warm up, thinking of you guys, unfortunately I can't get them all going at the same time!
@martin  8554L RF section (up to 1200MHz)

[Inverted18650]

Completed projects. Both the 190VDC reference and the 190mv, 1.9V, and 19V reference.



The updated and final schematic for the 190mv, 1.9V, 19V reference.



The next challenge: a stable 500VDC reference. Will start some design/build work this week.

Other news: The Fluke 8810A is on the UPS truck for delivery.

This will teach @med not to start a 'proper thread' for his Vref project.    Way back weeks and weeks ago I went searching to find this

Just running some numbers today on a Hamon divider I am building and looking at output loading by switching from 10Meg meters to 10Gohms+ meters. The answer is it does matter in particular at the 100:1 range divider range. I have included a screen cap of the spreadsheet I am playing with to give you an idea and the resistor values. Block one is a 10Gohm block 2 and 3 are for 10Meg with three getting a tweak to 10.01V so I can sort out what sort of range I need the input voltage to vary so I can use it as a transfer standard.

What this means is just make sure with your numbers that the Siglent matches the input impedance of what you are comparing or trying to transfer to in your Rabbit Hole much as it will only effect the LSD but it matters

What reference is under test here? For that deviation it seems the output can only drive a teeny-tiny current at best. So why build a STD that an off the shelve DDM may have trouble with.

[Inverted18650]

DANGER WILL ROBINSON
NIXIE PORN AHEAD
Doing my monthly warm up, thinking of you guys, unfortunately I can't get them all going at the same time!
@martin  8554L RF section (up to 1200MHz)

Id have to cut a hole about waist high into the side of that rack! For cables of course...

[jlw]

I was [thought I was directly] replying to bd139 about his Racal 9915 vs mine.  Long time reader, first time member.  Maybe someday the threading mechanics of this forum will become apparent, but I won't hold my breath.

A quick answer to what test equipment interest I have can be had at http://web.jlw.com/test.html .

[beanflying]

What reference is under test here? For that deviation it seems the output can only drive a teeny-tiny current at best. So why build a STD that an off the shelve DDM may have trouble with.

It's not a current or voltage loading issue with the reference in most cases as on 10V in using the 10:1 network I am looking at it is only 1mA. What is the issue is the difference between dropping a parallel 10Meg resistor (Meter) across say a 1k divider leg in my example above.

With 10:1 a 10Gohm gets 0.999,999,978 V 10Meg gets you 0.999,977,501 across 1k (2x500 ohm) at the probe or test points for a 10V in. So not an issue for a high impedance meter be it null or upper end digital but it is a potential issue with 10Meg meters or if you have the wrong impedance set.

Try loading your Fluke 731B with a handheld meter for example then drop a bench meter on Gohms and look at the difference. I ran a test on my HP 735A the other day for another thread and transferred the voltage from my 34401A set to 10M to my 121GW which is 10M so the value read should match.

[beanflying]

I was [thought I was directly] replying to bd139 about his Racal 9915 vs mine.  Long time reader, first time member.  Maybe someday the threading mechanics of this forum will become apparent, but I won't hold my breath.

A quick answer to what test equipment interest I have can be had at http://web.jlw.com/test.html .

Quick check of your link credentials - APPROVED with gear to spare  You seem to be deficient in the quantity of Multimeters so keep working on it