Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1808587 times)

Neomys Sapiens, Sam Spastic, FransW, 0culus and 12 Guests are viewing this topic.

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4008
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39225 on: September 19, 2019, 05:50:31 pm »
So.....fixed the battery problem. Now have 6 volts to the board. The TI-95 came up said "Memory Cleared" and then died. Completely dead. Went down in a blaze of glory.

Oh well.  :-// :-DD
An old gray beard with an attitude.
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 3673
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39226 on: September 19, 2019, 06:09:41 pm »
Replace the negative side wire as it is most likely black as death.
Coffee, Food, R/C and electronics nerd in no particular order :)
 
The following users thanked this post: mnementh

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4008
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39227 on: September 19, 2019, 06:32:29 pm »
The B&K 3010 physical restoration is complete. Case painted and front panel cleaned. Will now go into the repair cue.

An old gray beard with an attitude.
 
The following users thanked this post: mnementh, bd139, Kosmic

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4008
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39228 on: September 19, 2019, 07:11:40 pm »
Likewise the B&K 1801 painted and front panel cleaned. Also calibrated so this one is complete.

An old gray beard with an attitude.
 
The following users thanked this post: mnementh, bd139, Kosmic

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11557
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39229 on: September 19, 2019, 07:25:09 pm »
med at work  :-DD

 
The following users thanked this post: xrunner, mnementh

Online xrunner

  • Super Contributor
  • ***
  • Posts: 4152
  • Country: us
  • hp>Agilent>Keysight>?
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39230 on: September 19, 2019, 07:27:17 pm »
 :-DD Oh that was mean!  :-DD
I am a Test Equipment Addict (TEA) - by virtue of this forum signature, I have now faced my addiction
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4008
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39231 on: September 19, 2019, 07:27:45 pm »
 :wtf: :-DD :-DD
An old gray beard with an attitude.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11557
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39232 on: September 19, 2019, 07:32:50 pm »
I joke - seriously speaking, it's a nice job and I rather like it :-+ :-DD

That was an excerpt from children's TV Saturday morning circa 2003. One of the few things I watched.

Some more joy:

 

Offline SoundTech-LG

  • Frequent Contributor
  • **
  • Posts: 475
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39233 on: September 19, 2019, 08:22:00 pm »
$230 dollars for that puppy in 1975, and it didn't even have the nice paint job!
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11557
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39234 on: September 19, 2019, 08:28:17 pm »
That was pretty cheap then. LED displays had just dropped, 74 series was still expensive.

 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4859
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39235 on: September 19, 2019, 09:01:03 pm »
So.....fixed the battery problem. Now have 6 volts to the board. The TI-95 came up said "Memory Cleared" and then died. Completely dead. Went down in a blaze of glory.

Oh well.  :-// :-DD

Yegads... hardcore Coppertopinoma!!!

Try pulling the memory module. Those things were notorious for that expansion slot being flaky; long before Nintendo. ;)

mnem
 

Online Kosmic

  • Frequent Contributor
  • **
  • Posts: 767
  • Country: ca
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39236 on: September 20, 2019, 01:44:55 am »
Sometimes ago I realized I could only measure resistance to about 1-2 GOhm with my best multimeter. This was completely unacceptable and I decided to correct the situation. I looked quickly at the cheap insulation tester from China but decided against it, because of the limited range and accuracy. I ended up finding something a lot better but also heavier :)

Got myself a General Radio 1644a. At the core, this is a self-contained wheatstone bridge designed to measure high value resistors. I can now measure up to a Peta Ohm (1000 Tera Ohm)  :-DD The device can also be used for insulation testing and test capacitor for leakage.




The interesting part about the Genrad 1644a is the self-calibration feature. You don't need super expensive equipment to calibrate and adjust the instrument. I serviced the instrument according to the manual and everything is now in specs. The main rheostat is quite impressive and can be adjusted with its 8 adjustment screws.



Measuring a Ohmite 200 GOhm 5%. Was reading 205 GOhm on the 1644  :)


« Last Edit: September 20, 2019, 03:37:16 am by Kosmic »
 
The following users thanked this post: xrunner, edavid, BU508A, med6753, mnementh, wch, grbk, 0culus

Offline wch

  • Frequent Contributor
  • **
  • Posts: 612
  • Country: us
  • aina varma, usein väärin
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39237 on: September 20, 2019, 02:00:29 am »
Sometimes ago I realized I could only measure resistance to about 1-2 GOhms with my best multimeter. This was completely unacceptable and I decided to correct the situation. I looked quickly at the cheap insulation tester from China but decided against it, because of the limited range and accuracy. I ended up finding something a lot better but also heavier :)

Got myself a General Radio 1644a. At the core, this is a self-contained wheatstone bridge designed to measure high value resistor. I can now measure up to a Peta Ohm (1000 Tera Ohm)  :-DD The device can also be used for insulation testing and test capacitor for leakage.


If you are going to go boat anchor, specialty boat anchor is the way to go. That box is in awesome shape.  Nice acquisition!   :clap:
specialization is for insects.
 
The following users thanked this post: Kosmic

Offline wch

  • Frequent Contributor
  • **
  • Posts: 612
  • Country: us
  • aina varma, usein väärin
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39238 on: September 20, 2019, 02:06:37 am »
Worked on the 3400A tonight. Powers up. Reads correctly on the .1 to 3V scales, doesn't do so well on the others. A lot of erratic meter movement. I just printed schematics for it, so I don't know much but I am wondering if one or both of the thermocouples has been fried... has anyone here tested the thermocouples on one of these?

That's the first question. The second is, does anyone have a parts mule? I need to replace the plug socket and fuse holder (worst case) or the whole back panel assembly (best case).  The plug socket is the old oval shape, so a back panel assembly with a modern plug socket would be ideal. PM me if you have something I might be able to use.

specialization is for insects.
 

Online Kosmic

  • Frequent Contributor
  • **
  • Posts: 767
  • Country: ca
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39239 on: September 20, 2019, 02:43:34 am »
Sometimes ago I realized I could only measure resistance to about 1-2 GOhms with my best multimeter. This was completely unacceptable and I decided to correct the situation. I looked quickly at the cheap insulation tester from China but decided against it, because of the limited range and accuracy. I ended up finding something a lot better but also heavier :)

Got myself a General Radio 1644a. At the core, this is a self-contained wheatstone bridge designed to measure high value resistor. I can now measure up to a Peta Ohm (1000 Tera Ohm)  :-DD The device can also be used for insulation testing and test capacitor for leakage.


If you are going to go boat anchor, specialty boat anchor is the way to go. That box is in awesome shape.  Nice acquisition!   :clap:

It's a boat anchor but still hold it's ground spec wise. Iet labs sell updated version of the 1644 and for some reason specs are worst  :-// The general accuracy of the 1644 is 1% and Iet labs 1864/1864 are 3%.

Got newfound respect for Genrad. Build quality is impressive. All the electrolytic are still in good shape  ^-^
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 6079
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39240 on: September 20, 2019, 02:47:17 am »
$230 dollars for that puppy in 1975, and it didn't even have the nice paint job!

From the inflation calculator, the price is equivalent to $1097.  :o

Online Kosmic

  • Frequent Contributor
  • **
  • Posts: 767
  • Country: ca
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39241 on: September 20, 2019, 03:14:56 am »
One of those Russian glass resistor. 1 TeraOhm 10%. was measured at around 0.92 TeraOhm.



 
The following users thanked this post: xrunner

Online xrunner

  • Super Contributor
  • ***
  • Posts: 4152
  • Country: us
  • hp>Agilent>Keysight>?
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39242 on: September 20, 2019, 03:20:43 am »
Wow.

Do you know what material they used to achieve that value of resistance?  :-//
I am a Test Equipment Addict (TEA) - by virtue of this forum signature, I have now faced my addiction
 

Online Kosmic

  • Frequent Contributor
  • **
  • Posts: 767
  • Country: ca
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39243 on: September 20, 2019, 03:30:19 am »
Wow.

Do you know what material they used to achieve that value of resistance?  :-//

Carbon film I would guess. But I have no idea really.
 

Offline tggzzz

  • Super Contributor
  • ***
  • Posts: 9859
  • Country: gb
    • Having fun doing more, with less
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39244 on: September 20, 2019, 06:29:29 am »
Sometimes ago I realized I could only measure resistance to about 1-2 GOhm with my best multimeter. This was completely unacceptable and I decided to correct the situation. I looked quickly at the cheap insulation tester from China but decided against it, because of the limited range and accuracy. I ended up finding something a lot better but also heavier :)

Got myself a General Radio 1644a. At the core, this is a self-contained wheatstone bridge designed to measure high value resistors. I can now measure up to a Peta Ohm (1000 Tera Ohm)  :-DD The device can also be used for insulation testing and test capacitor for leakage.

...

One of those Russian glass resistor. 1 TeraOhm 10%. was measured at around 0.92 TeraOhm.

Tasty!

Does it also measure air humidity and fingerprint conductivity?

Are you going to be going down the PTFE wire insulation route now?
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".
Having fun doing more, with less
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11557
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39245 on: September 20, 2019, 06:50:22 am »
Don’t forget finger cots (I hate those bloody things)
 

Offline paschulke2

  • Contributor
  • Posts: 26
  • Country: de
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39246 on: September 20, 2019, 06:52:34 am »
Worked on the 3400A tonight. Powers up. Reads correctly on the .1 to 3V scales, doesn't do so well on the others. A lot of erratic meter movement. I just printed schematics for it, so I don't know much but I am wondering if one or both of the thermocouples has been fried... has anyone here tested the thermocouples on one of these?

If it works in one range, there's most likely nothing wrong with the video amplifier, the chopper amp and the thermo couple. Your problem is most likely a dirty range switch—simply clean it. And: Please don't mess with the thermo couple!

I need to replace the plug socket and fuse holder (worst case) or the whole back panel assembly (best case).  The plug socket is the old oval shape, so a back panel assembly with a modern plug socket would be ideal. PM me if you have something I might be able to use.

The fuse holder should be (more or less) a standard part. With a bit of metal work (not too hard because it's aluminum) it should be possible to retrofit an IEC plug.

- Thomas

PS: Please don't mess with the thermo couple!
 

Offline zucca

  • Supporter
  • ****
  • Posts: 2003
  • Country: it
  • EE meid in Itali
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39247 on: September 20, 2019, 07:19:41 am »
I canceled Netflix, this TEA thread is what I need to relax.
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 
The following users thanked this post: mnementh, ThickPhilM

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 3673
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39248 on: September 20, 2019, 08:01:17 am »
I canceled Netflix, this TEA thread is what I need to relax.

Got one of our local online ones wanting me to rejoin offering a 'free' month after I dumped them 3 or 4 months ago and AMAZON wants to sign me up after a 'free' month. None of the above at this stage ......
Coffee, Food, R/C and electronics nerd in no particular order :)
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 3673
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #39249 on: September 20, 2019, 08:24:18 am »
Move fast USA mob eBay auction: #133167557354 cheep cheep  ;)
Coffee, Food, R/C and electronics nerd in no particular order :)
 
The following users thanked this post: xrunner


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf