Test Equipment Anonymous (TEA) group therapy thread

[W6EL]

Peter_O, what is the voltage reference used in the E3632A? I was just wondering the other day how accurate one can expect these things to be.

[factory]

The E3632A has been produced quite some time, as you can buy it branded HP, Agilent or Keysigth.

The KR serial number seems to break with the standard HP rule. Does anybody have a clue about the year of production? As a pre-Agilent it should be some 19xx.
 

That is strange, going by the post 1960 rule, it would have been will be made 12 years in the future  , maybe they will have got rid of the stupid name changes & gone back to being HP by then. 

I've found a reference to a joint venture with Samsung in Korea back in 1987, Samsung Hewlett Packard (SHP) featured in the measure newsletter; http://hparchive.com/measure_magazine/HP-Measure-1987-03-04.pdf

Doubt the VFD will be a problem unless you plan on using it 24/7 and leaving it powered up all day, as companies do.

David

[Peter_O]

Peter_O, what is the voltage reference used in the E3632A? I was just wondering the other day how accurate one can expect these things to be.

Yea, you are right.
According to the service manual they use the reference inside the 16bit DAC IC.

The Datasheet of the PSU states 0.05% + 10mV, 0.05% + 5mV for readback.
https://www.keysight.com/us/en/assets/7018-06785/data-sheets/5968-9726.pdf

So my unit seems to be in the right ballpark already.

[W6EL]

Peter_O, what is the voltage reference used in the E3632A? I was just wondering the other day how accurate one can expect these things to be.

Yea, you are right.
According to the service manual they use the reference inside the 16bit DAC IC.

The Datasheet of the PSU states 0.05% + 10mV, 0.05% + 5mV for readback.
https://www.keysight.com/us/en/assets/7018-06785/data-sheets/5968-9726.pdf

So my unit seems to be in the right ballpark already.

Ten times better than a 78XX regulator Well, much better really, since it can be calibrated and all that. What a lucky find!

[W6EL]

I asked Fluke if they had any documentation on the Fluke 633A, as I can find hardly any mention of it anywhere, let alone a service manual.

Elliot,
 
Unfortunately, due to this item being obsolete many years ago, we no longer have any service manuals available.  Sorry for the inconvenience.
 
Thank you.

They must love these super important web inquiries from the eevblog TEA...

In all seriousness, it looks like the Fluke 633A has a pair of LM305H voltage regulators, which use the Fluke 730A reference cards as their reference. I need to really draw it out carefully, as it wasn't obvious to me how or why they did this. In particular, the negative supply seems to begin as about -10V unregulated, and then is referenced to -10V, and comes out as -10V. The positive side, on the other hand, has 14V unregulated coming in and comes out at an expected +10V. Since I don't believe they would try and regulate with zero margin on the negative side, I just assume I've got something backwards about how they are doing so. I will eventually get in there and back out a schematic. My end goal though will be to average the two Fluke 730A ref cards and produce a good reference from it. Maybe with an oven, we will see.

[Peter_O]

Just bought two bags of HP plotter pens.
Best before 1993.

Just opened one bag and did a test: They are just writing perfectly starting from the first millimeter. 

I'm shocked.

[m k]

Real thing vs. new thing.

You're conditioned towards premature aging.

[TERRA Operative]

Nice, that bodes well for the couple bags of plotter pens I have still sealed up.

One day I'll get around to making a serial/USB to gpib adapter for the plotter to hook it to my PC for some fun.

[m k]

Newegg has old NI HS for $75, seems to be in Hong Kong.
(other place is renting one 41€/week)
2xUSB MCU board can act as a print server, if needed, maybe it's already done.

Pens,
I have a faint memory that a bit before that experity year one architect argued against some pens.
Can't remember was is a brand or something else, but some pens dried almost instantly if left open when others seemed to be ageless.

Maybe it was still time when in house sales board writers had to occasionally take a break and get some fresh air.
Nowadays that kind of a process must be something that includes under pressured area and hazmat suits, if not totally illegal.
[link to extra large felt marker here]

It also brought up a mass printer of mass printers, Diconix.

But wouldn't water soluble ink be better here.
The pen has so small spot from where the ink comes out that surface tension effect of water must be superior against alcohols.
Peter_O can check that by dropping some water on those plottings.

[Ice-Tea]

Anyone up for a project?

Agilent PSU. Recapped it ages ago, didn't solve the problem. Poked around a bit, seems the 5Vsb doesn't come up, I'm guessing shorted somewhere.. Don't really have the time to dig further but I still need to get this fixed.

Preferably EU if possible.I'd be happy to pay for a result, I can have Farnell deliver whatever spare parts you need.



PM me if interested ;-)

For those not interested: T&M gear guts of the day. E1412A 6.5d VXI card. Essentially a 34401A in VXI format. Identical down to the reference designators.

[AVGresponding]

Anyone up for a project?

Agilent PSU. Recapped it ages ago, didn't solve the problem. Poked around a bit, seems the 5Vsb doesn't come up, I'm guessing shorted somewhere.. Don't really have the time to dig further but I still need to get this fixed.

Preferably EU if possible.I'd be happy to pay for a result, I can have Farnell deliver whatever spare parts you need.



PM me if interested ;-)

Ugh... my repair queue is already disreputably long enough without adding other people's troubles to it...

For those not interested: T&M gear guts of the day. E1412A 6.5d VXI card. Essentially a 34401A in VXI format. Identical down to the reference designators.

Not that identical; the COTO relay isn't rubbing its insulation off against the GDT in that layout: https://www.eevblog.com/forum/testgear/check-your-34401a-multimeter/

[Ice-Tea]

Not that identical; the COTO relay isn't rubbing its insulation off against the GDT in that layout: https://www.eevblog.com/forum/testgear/check-your-34401a-multimeter/

Heheh... didn't say layout ;-) I already checked K101. Seems to work fine ;-)

[m k]

I've heard that Vince has free time.

[Vince]

No MK you got that wrong ! I have zero free time, a house and garage to build and a million of my own projects / repair / restorations to work on !
this week-end is sunny at long last, so I will mandatorily (Firefox spell-checker doesn't think it's a word, somehow) use this rare precious sunny week-end to work outside and try to make some progress on restoring an antique large wooden drawer cabinet, 26 drawers... starting with sanding / refreshing the drawers. Managed to do 11 of them 2 weeks ago. Tomorrow if I start work on it at 10AM at the latest, I calculated I might be able to do the remaining 15 drawers before it gets dark. I timed myself, I need about 25 minutes of sanding to refresh one single drawer. If I somehow manage to do that, then on Sunday, meant to be sunny as well, I will move on to sanding the frame / structure of the cabinet... tiny palm orbital sander won't cut it though, so I bought a rotary polisher / sander for the occasion. If it works well, I might have the frame finished on the same day.... really hope so anyway, as it will probably break my back getting the freaking thing out and bringing it back inside... so I would rather avoid having to do it twice or thrice if I can help it...

So, I have zero time MK.... I think you are mistaken with the old Vince, the one of 2 years ago that got fired and spent a year at home sanding and painting the dry walls for the first 6 months, then the next 6 months spent sorting his millions of salvaged components one by one and putting them in little drawers..... yes, I had lots of time back then.... but 18 months ago I found a new job and now the new Vince has zero time for anything but his own stuff, and even then, he can't get 90% of his stuff done either, so he must decide what are the most urgent / important 10% that will, maybe, actually get done....

[zrq]

Is there any advice for a "preventive maintenance" of a old Fluke 5200A ACV calibrator? There are some threads on lengthy repairs of it, which scared me a lot. Maybe replacing tantalum capacitors as a start, and also some high power carbon composite resistors like the R40 and R46 on the A7 (thanks Rax).

It was rescued from a trash dump together with a Fluke 5220A transconductance amplifier, both seems fully operational. Although I'm not a voltnut, considering either I keep them or they will be destroyed along with other e-wastes, I decided to keep them and use them as general purpose sources. Or I can consider giving them away if a fellow voltnut would like to pick them up in Switzerland (>20 kg each).

[Kosmic]

Is there any advice for a "preventive maintenance" of a old Fluke 5200A ACV calibrator? There are some threads on lengthy repairs of it, which scared me a lot. Maybe replacing tantalum capacitors as a start, and also some high power carbon composite resistors like the R40 and R46 on the A7 (thanks Rax).

It was rescued from a trash dump together with a Fluke 5220A transconductance amplifier, both seems fully operational. Although I'm not a voltnut, considering either I keep them or they will be destroyed along with other e-wastes, I decided to keep them and use them as general purpose sources. Or I can consider giving them away if a fellow voltnut would like to pick them up in Switzerland (>20 kg each).

Personally I would not touch anything if it's working fine. Maybe juste check the voltages of the different supply lines ? page 4-63 of the service manual describe typical values.

Be carefully when opening this beast there is lethal voltage inside.

[Ice-Tea]

No MK you got that wrong....

I'm 100% sure I could offer you something from my repair rack that would make you reconsider 

[TERRA Operative]

Picked up some N-type cables and an 8494B 11dB adjustable attenuator. It is spot-on through all of it's steps.

See how much the cables cost new? https://www.keysight.com/us/en/product/N6314A/n6314a-test-port-cable-type-n-50-ohm.html

I got two of them for 2200yen each, in great condition. They will be put to good use on my Siglent VNA.

[Peter_O]

snip:
But wouldn't water soluble ink be better here.
The pen has so small spot from where the ink comes out that surface tension effect of water must be superior against alcohols.
Peter_O can check that by dropping some water on those plottings.

No need to test. It says "water based" on the bag.
That's what I wanted: To be able to soak with water and refill with jet ink.
That there is no need right at the beginning is a nice plus.

[Robert763]

Picked up some N-type cables and an 8494B 11dB adjustable attenuator. It is spot-on through all of it's steps.

See how much the cables cost new? https://www.keysight.com/us/en/product/N6314A/n6314a-test-port-cable-type-n-50-ohm.html

I got two of them for 2200yen each, in great condition. They will be put to good use on my Siglent VNA.

If you think those are expensive try buying a phase stable microwave cable https://www.keysight.com/us/en/options/85134E/85134f-flexible-cable-2-4-mm-3-5-mm.html

[m k]

this week-end is sunny at long last, so I will mandatorily (Firefox spell-checker doesn't think it's a word, somehow) use this rare precious sunny week-end to work outside

One of our weather forcasts has next day divided so that noon is dropped out.
So the whole six day period has only one spot for possible sun, that current day noon.
There are still clear weather markings of course but the actual mark is Moon.

snip:
But wouldn't water soluble ink be better here.
The pen has so small spot from where the ink comes out that surface tension effect of water must be superior against alcohols.
Peter_O can check that by dropping some water on those plottings.

No need to test. It says "water based" on the bag.
That's what I wanted: To be able to soak with water and refill with jet ink.
That there is no need right at the beginning is a nice plus.

I remember that permanent ink in large sized ink jets were not drying so easily.
That's devices with separated ink tanks, hoses and stuff.
Maybe their systems were more gas tight.

Then the quiz.
(have I posted these already)

Anyway, on or off?

[K0ELB]

It’s been a while since I’ve posted on this thread, just moved last August to a bigger house with a dedicated 18’x33’ finished lab in the basement so I figured I’d update my equipment post. Everything in the picture works, I just got the 575 curve tracer #2 today, and it works fine with just a little cleaning. The other 575 I got about two weeks ago and it’s the same for it, just needed cleaning. The 545 on the cart needed some new HV caps and a thorough cleaning, and it’s up and going perfectly too.

Not to mention all the HP stuff in the rack plus another HP 5326B nixie counter/DMM that’s on the desk/bench. 

Getting out of a small house and getting the test equipment into it’s own dedicated room was the best thing I’ve ever done.

[Vince]

Wow ! Congratulations on your giant lab ! 
I can only dream of such a big lab... I am in the process of building a similarly sized... garage/workshop, but sadly only a very small part of it will be able to be dedicated to TE stuff. That would be to store all my hollow-state Teks that are either for parts, or awaiting restoration.

I hope you have some kind of ventilation and/or heating system in that basement, to keep humidity from ruining all that nice TE ?

Not one but TWO 575 in just two weeks  ?! That's insane ! Are they so easy to find, and so cheap in the US that you can afford a pair of them ?! 

Here in Frogland they are super rare (maybe one every year or two) and ultra expensive.

I got mine 2 and a half years ago, and since then, the only other one that popped up is this one, a year ago maybe, priced at 1,500 Euros no less (add 10% to convert that to US dollars...), for what appears to be, literally, a " barn find", as is ! 

https://www.leboncoin.fr/equipements_industriels/2264660895.htm

Recently, a month ago, seller lowered the price to 1,000 Euros but still ! 

Anyway, so cool to see other people caring for these 575, two of them even, in a nice comfy lab to boot 

Do any of your units feature the high-voltage / 400V mod, or are they both the standard 200V versions ?

I am planning on using the 575 to test vacuum tubes as well as semi-conductors (to help me restore the other Tek scopes  ), so I would kill to have the 400V version, so I can properly test vacuum tubes up to their actual operating voltage. 200V is good enough to test the tubes for proper operation and "health" of course, but how nice would it be to be able to test them up to full operating voltage 

[K0ELB]

I got lucky and caught this last one at $475/best offer. I offered $400 and they took it. The first one was $675 and I offered $500 and they accepted that. Total luck, I thought I was low-balling them for what they are. Shipping on each wasn’t too bad, but better on the second one.

Luckily, they’re both Mod122C with the 400v. That’s the whole reason why I wanted them.

The basement is temperature controlled year round. Humidity is low and I do keep an eye on it. And yes, I bought these with the main purpose of checking tubes as well as transistors. I repair stereos as a hobby so being able to match transistors is very handy. And the basement room is not just a lab, it’s also my ham radio shack as well as my music listening area. Here’s a vintage McIntosh set that I repaired, minus the MR-77 tuner which was already restored when I got it. The preamp is a C26 and the amp is an MC2505. I also rebuilt the Dual 1019 turntable on top, and it’s my main turntable. The other end of the room has the test equipment as well as several Collins R-390A’s, a Collins S-Line set, 75A-4, and a Central Electronics 200V transmitter. I’ve pretty much claimed this room as mine.

[Vince]

Wow, both are 400V, I am more than jealous, I am ... lacking words.

Maybe one day I will find one.... no wait, I will just shoot Tek an e-mail asking them if they would be so kind as to sending me a parts kit for that mod ! Surely they must still have some in stock 60 years later

Lucky you could get them shipped to you ! Here, you can't ship them. Too large and too heavy. Mine was located 400+ kms away in the middle of nowhere. Had to drive there, which took 12 hours of driving and cost as much in fuel and tolls than the 575 itself but... it was a price I was willing to pay to have the honour and privilege of owning one of these beauties.... zero regret 2+ years later.

Your basement looks like a comfy living room, you must have worked long and hard on it to get there ! 

I know squat about audio stuff , other than the two QUAD 33/303 pre-amp/amp I fixed recently.

Nice touch to embed your gear inside the wooden furniture. First time I see someone making the effort. Keeps the dust out, easier to keep clean !

My eyes can't help but notice in the lower left corner of the picture, a hint of an ancient HP piece of TE.... maybe we could see a proper pic of it ? Model number ? What kind of TE is it ?

A year ago I had the opportunity to rescue two HP 416B in the same form factor and era, that were destined to the scrappy sadly, as nobody wanted them apparently.
They are SWR meters, so you could use them for your radios I guess, to tune antennas and what not... but as for me I am not at all into RF or radio. I have zero use for these things, and most likely never will.... but I find them so cuuuute, so sexy up close, not to mention the magic eye tube, and so pleasurable to fiddle with, and they are a piece of HP history, and in such a nice shape.... I just could not resort to seeing them being scrapped. So I rescued them. So now I have two boat anchors taking huge space in my tiny over crowded house, that I don't even use... but such is life