Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1612594 times)

ThickPhilM, Neomys Sapiens, mnementh, BU508A, factory, Specmaster, wch, med6753 and 16 Guests are viewing this topic.

Online med6753

  • Super Contributor
  • ***
  • Posts: 3456
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10450 on: May 09, 2018, 02:22:31 am »
Looking good  :-+

Have a look round the intensity control and HV divider resistors. They all seem to go a bit drifty.

Had a similar situation with a B&K 2120 scope where the focus divider resistors went wonky. Tomorrow I'll be diving into the 465 CRT circuit.

I have a B&K PR-28 HV probe which I've used several times and is fairly accurate. It hasn't seen any use in many years but it looks like it's gonna get a workout. 
An old gray beard with an attitude.
 

Offline orin

  • Frequent Contributor
  • **
  • Posts: 426
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10451 on: May 09, 2018, 02:48:27 am »
To return the favour, an HP 436A power meter that might tempt the RF types, if you can find a sensor for it at a reasonable price.

https://www.ebay.co.uk/itm/power-meter/183205793888?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Currently no bids, £0.99 and 1 day 13 hours to go.

I’m sure there’s like a billion orphaned HP power meters out there. Everyone had got to have blown all the sensors up by now.

A sensor at a reasonable price?!?  :-DD

I haven't seen an 848x N series sensor that didn't just scream "Run for the hills, I've been toasted then toasted again by multiple dumbasses in succession" selling less than $300 in years, and then another $50-100 for a cable. Maybe that's my bad luck, I dunno.

mnem
*Toddles off to ded*


Other then the usual ebay rules (pulled from a working environment: broken etc.)
Any sensor selling for less than $200 is broken.
A rebuilt 8481A will cost $450 obo on ebay.

You'll need a network analyzer to test them properly.  Just be cause one zeros and reads 0dBm doesn't mean it's not damaged - I had to return an 8481A due to bad SWR over 1GHz.

They aren't all broken - I did get a working 8482A for around $200.

Which reminds me - I have to put the 8484A on the VNA and check it.  8484As tend to be cheaper, but read -70 to -20 dBm and drift a lot.  Useable if you keep a 30dB attenuator on it at all times.
 

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 3396
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10452 on: May 09, 2018, 02:51:29 am »
A rebuilt 8481A will cost $450 obo on ebay.

"obo"? My mental dictionary can't fill that in.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Online PA0PBZ

  • Super Contributor
  • ***
  • Posts: 3983
  • Country: nl
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10453 on: May 09, 2018, 03:00:44 am »
"obo"? My mental dictionary can't fill that in.

Or Best Offer
Keyboard error: Press F1 to continue.
 

Offline GerryBags

  • Frequent Contributor
  • **
  • Posts: 334
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10454 on: May 09, 2018, 03:00:54 am »
Sounds like a "Loot-ism". £375 ono would be our eq. as I'm guessing it's "or ballpark offer".
 

Online BravoV

  • Super Contributor
  • ***
  • Posts: 5872
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10455 on: May 09, 2018, 04:49:24 am »
Do I see "Goodwill Industries" on the paper in the baggie, and a hand-scribbled sticker on top of the unit?  :-DD This does not bode well...  ;)

mnem
*Toddles off, even dedder now*

Its a signal or a function generator?

Hmm .. Goodwill "Industries" ?  ::) C'mon, I thought you're senior TEA member here, its "Instruments"  :-DD ... aka Good Will "Instruments" ... aka GW Instek.

Not much in audio, its just its so tempting as its so new, and just look at the BNC connector, barely any scratch at all.

I will just leave you guys with the attached photos.  :P

Online Specmaster

  • Super Contributor
  • ***
  • Posts: 7215
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10456 on: May 09, 2018, 04:58:37 am »
Nice piece of kit, I was guessing a Signal Gen because I saw the BNC plug and the croc clips on the lead in the packet  ;D
Who let Murphy in?
 

Online bd139

  • Super Contributor
  • ***
  • Posts: 10613
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10457 on: May 09, 2018, 05:45:12 am »
Yes indeed very nice.

Sooooo when do we get to see it unclad?  :-DD
 

Offline orin

  • Frequent Contributor
  • **
  • Posts: 426
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10458 on: May 09, 2018, 05:45:39 am »
"obo"? My mental dictionary can't fill that in.

Or Best Offer


Yeah, ebay's "Make Offer" button is labelled "Best Offer:" - on the US site at least.
 

Offline bitseeker

  • Super Contributor
  • ***
  • Posts: 7695
  • Country: us
  • Lots of engineer-tweakable parts inside!
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10459 on: May 09, 2018, 01:13:35 pm »
Do I see "Goodwill Industries" on the paper in the baggie, and a hand-scribbled sticker on top of the unit?  :-DD This does not bode well...  ;)

mnem
*Toddles off, even dedder now*

Its a signal or a function generator?

Hmm .. Goodwill "Industries" ?  ::) C'mon, I thought you're senior TEA member here, its "Instruments"  :-DD ... aka Good Will "Instruments" ... aka GW Instek.

Not much in audio, its just its so tempting as its so new, and just look at the BNC connector, barely any scratch at all.

I will just leave you guys with the attached photos.  :P

Looks like new! :-+
I TEA.
 

Online BravoV

  • Super Contributor
  • ***
  • Posts: 5872
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10460 on: May 09, 2018, 04:39:06 pm »
Yes indeed very nice.

Sooooo when do we get to see it unclad?  :-DD

Yeah, thats the plan and will post the pron photos in this forum.  :P

Online Specmaster

  • Super Contributor
  • ***
  • Posts: 7215
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10461 on: May 09, 2018, 09:05:59 pm »
According to the RS site, my meter has actually been dispatched so it could very well be back with me tomorrow, I'm getting all excited about that because if that happens and the meters all calibrated nicely, then that is excellent service, especially when you factor in that the carriage is also included in the cost, and that is 24hr service.

I sold a meter this week and it cost me £13.14 for 48hr service to send it to the buyer, but I'm getting 24hr service from the same carrier inclusive both ways!!! :-+
Who let Murphy in?
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 3456
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10462 on: May 09, 2018, 10:53:25 pm »
The +55V reference required an adjustment to nominal. The HV was approx 200 volts low. The CRT bias needed just a tweak. Result? Nice, bright trace. More than enough intensity.

Left to do: The vertical attenuator switches are dirty plus it looks like Channel 1 on some settings is stuck on X100 and channel 2 stuck on X10. I need to figure out how to get at the switch decks without pulling the entire board. Then a complete calibration. The time base is off plus the DM44 also needs a calibration.

In the meantime I put it back into the case and I want to give it a good burn-in to see if anything craps out. I do have a pretty good supply of tant caps in case another one decides to commit suicide.

This has been a fun project!  :-+
An old gray beard with an attitude.
 
The following users thanked this post: Cubdriver

Online bd139

  • Super Contributor
  • ***
  • Posts: 10613
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10463 on: May 09, 2018, 11:24:29 pm »
Awesome. Another one saved!  :-+
 

Online mnementh

  • Super Contributor
  • ***
  • Posts: 4353
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10464 on: May 10, 2018, 03:15:25 am »
Do I see "Goodwill Industries" on the paper in the baggie, and a hand-scribbled sticker on top of the unit?  :-DD This does not bode well...  ;)

mnem
*Toddles off, even dedder now*

Its a signal or a function generator?

Hmm .. Goodwill "Industries" ?  ::) C'mon, I thought you're senior TEA member here, its "Instruments"  :-DD ... aka Good Will "Instruments" ... aka GW Instek.

Not much in audio, its just its so tempting as its so new, and just look at the BNC connector, barely any scratch at all.

I will just leave you guys with the attached photos.  :P

 

 :palm: Seriously? The LOL and Wink weren't enough evidence I was yanking your chain? Damn, I wish we had a "tongue-in-cheek" emoji...  |O


Seriously though... awresome score. NIB indeed. What's the label I saw on the top? An inspector signoff?



Houston, we have a trace! The 110V supply is fixed and the scope came up. Checked all the supply voltages and they are OK. But the trace is dull even with full intensity. So I'll have to dive into the CRT circuits and see what's up. I have a suitable HV probe and I respect the HV area especially since I cut my teeth on vacuum tube circuits. Hopefully it will just need some adjustments.

There's life in the old beast after all!  :-+ :-+ :-+
The +55V reference required an adjustment to nominal. The HV was approx 200 volts low. The CRT bias needed just a tweak. Result? Nice, bright trace. More than enough intensity.

Left to do: The vertical attenuator switches are dirty plus it looks like Channel 1 on some settings is stuck on X100 and channel 2 stuck on X10. I need to figure out how to get at the switch decks without pulling the entire board. Then a complete calibration. The time base is off plus the DM44 also needs a calibration.

In the meantime I put it back into the case and I want to give it a good burn-in to see if anything craps out. I do have a pretty good supply of tant caps in case another one decides to commit suicide.

This has been a fun project!  :-+


 

Houston here!  ;)

Nicely resurrected! Makes me daydream about diving into my 454 again... but not likely gonna happen any time soon. Same with the 2230. In all reality, neither is likely going to get any attention before I have to move, so I guess I need to find them both a good home.

Anybody interested in a Tek 454 with the ubiquitous intermittent HV fault, or a Tek 2230 with a High-Speed Storage write error (I know there's noise on the 5V rail and I suspect that's the cause as it gets past the low-speed write test with no errors) that does work in analog and acquisition modes once you punch past the error messages, PM me. Both have bright, clear trace.

I'm most interested in them going to a good home, so come on, git you some.


 

mnem
*Cleaning House*
« Last Edit: May 10, 2018, 04:33:47 am by mnementh »
 

Online bd139

  • Super Contributor
  • ***
  • Posts: 10613
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10465 on: May 10, 2018, 03:16:54 am »
I’d have that 454 if you were in the U.K.  rebuilding the HT on them looks like fun.
 

Offline rhb

  • Super Contributor
  • ***
  • Posts: 2549
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10466 on: May 10, 2018, 01:14:45 pm »
Please pray for me. 

I'm thinking about buying an Agilent MSO8104A.  I have tried to walk the strait and narrow, but I fear that I shall stray again into the ways of wickedness so that I may measure things which do not need measuring.

Brothers and sisters, will you stand with me and turn me from temptation?

Can I have a witness?  Will you testify?  How did you overcome your addiction?
 

Online mnementh

  • Super Contributor
  • ***
  • Posts: 4353
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10467 on: May 10, 2018, 01:19:17 pm »
I have so many Tek 'scopes I've been forced to give 2 of them up for adoption because I can't afford to feed or clothe them. I can't help you.  :-DD


mnem
Pants are highly overrated.
 

Offline rhb

  • Super Contributor
  • ***
  • Posts: 2549
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10468 on: May 10, 2018, 01:52:40 pm »
You fill my heart with sorrow  and  dread.  My 465 is comatose and I fear the morning like a soldier about to assault the enemy.  Through the dark hours I am tormented by the products of oriental perfidy and promises not fulfilled.  Whatever shall become of me?
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 3456
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10469 on: May 10, 2018, 02:25:10 pm »
You fill my heart with sorrow  and  dread.  My 465 is comatose and I fear the morning like a soldier about to assault the enemy.  Through the dark hours I am tormented by the products of oriental perfidy and promises not fulfilled.  Whatever shall become of me?

I just brought a comatose 465 back to life. You must repent and do the same. Feed your addiction. There is no hope for us.
An old gray beard with an attitude.
 

Offline Brumby

  • Supporter
  • ****
  • Posts: 9052
  • Country: au
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10470 on: May 10, 2018, 04:37:03 pm »
I wish I had a 465 - even a comatose one, but they aren't plentiful down here.

Makes me feel somewhat of a fraud posting here.  A 465 just seems to be a key part of the right of passage....  :(



.... and they have a good array of knobs and switches to bedazzle those who lack scope understanding.   :D
« Last Edit: May 10, 2018, 04:38:43 pm by Brumby »
 

Online bd139

  • Super Contributor
  • ***
  • Posts: 10613
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10471 on: May 10, 2018, 04:39:20 pm »
I got though more 465’s than shoes in the last 5 years  :-DD
 

Online Specmaster

  • Super Contributor
  • ***
  • Posts: 7215
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10472 on: May 10, 2018, 04:43:20 pm »
Haha just think how many tants you also got through in that time
I got though more 465’s than shoes in the last 5 years  :-DD

From mobile device so predictive text might have struck again

Who let Murphy in?
 

Online bd139

  • Super Contributor
  • ***
  • Posts: 10613
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10473 on: May 10, 2018, 04:45:15 pm »
I reckon a couple of hundred so far. And they’re not bloody cheap!
 

Online BravoV

  • Super Contributor
  • ***
  • Posts: 5872
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #10474 on: May 10, 2018, 05:23:37 pm »
Seriously though... awresome score. NIB indeed. What's the label I saw on the top? An inspector signoff?

Looks like a company's inventory label, its from a defunct computer crt monitor factory.


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf