Test Equipment Anonymous (TEA) group therapy thread

[Wolfgang]

Even after all these decades of using calculators with an = key, after about 10 minutes using RPN, it just went "click". I totally get it!!

I like the mentality of gathering all the operands, then operating on them. In the same way I gather all the components on my desk, and only then start soldering them into the circuit.

And that's totally why RPN works. I realised very quickly that using RPN is actually the way we were taught to do things at school. You wrote down the first operand, then wrote the second one underneath it and the operation you were doing to the right of that. Then you proceeded to apply your operator to the rows and columns of digits, writing down the answer underneath.
Not an = sign in sight!

All the glory of RPN ends when you have to process large formulas with a lot of bracketed terms and you need find a way inside out and not left to right. RPN ist a way of misusing a human brain as stack memory. Humanity invented compilers to avoid that.

[mnementh]

Meanwhile, in a Facebook vintage electronics group, these photos were posted today of this person's collection of meters and test gear, impressive or what?

Niiiiiiiiiiiiiiiiiiiiiiice.

I like collecting the rare Avos. Think I have most of them apart from the first ever one made.

Thank you for thinning the herd, so I'm not constantly molested by them. 

mnem
*agitating-ily*

[mnementh]

I loved microdrives! Well, not to store information, but the same way some people love auto-wind wristwatches. Tiny electromechanical enginerdery just for the sake of being tiny!

mnem
...and it has nothing to do with the fact I made a freaking mint fixing microdrive-equipped iPods back in the day...

The microdrives being referred to are the dread Sinclair microdrives

   I suspect you're referring to something else. 1" HDDs?   

What the actual fuck... am I looking at? Is that a looped reel tape cartridge of some sort...? In what universe is that "micro"...?

I'm sorry... I have never ever seen this technology before. Did it maybe die the ignoble death it deserves before ever escaping your shores...?

mnem
mom: "You learn something new every day."
me: "Sometimes what you learn... is something better left unknown."

[Cerebus]

What the actual fuck... am I looking at? Is that a looped reel tape cartridge of some sort...? In what universe is that "micro"...?

Yes, classic "endless tape" but packed into a very small space, thus very narrow tape. Can't remember the width (this was early-mid 1980s so forty years ago), but it made 1/8" cassette tape look like a hawser.

[bitseeker]

Just got the  HP 3551A Transmission Test Set delivered ...

It's in bad shape 

It's in the garage now because it's got that ancient military surplus / old ham radio shack smell emanating. But here's a teaser pic. Severe corrosion from what I think is bad batteries. Oh dear ... 

More pics tomorrow I expect.

Condolences...well, hopefully the rest is OK.

It was sold cheap as-is for parts not working. I only bought it for parts and not expecting to restore it. If it was something I wanted to use or had a chance of being a restoration candidate I might have changed my mind. But it isn't looking that way and that will be OK. I'll salvage the good parts as I had planned and they will go to a deserving TEA item or to someone else who needs a knob or other hp part.

Yeah, the front panel, alone, has a lot of good reusable parts. Some, though, like the binding posts, may be similar looking but different on the back side. Looking forward to seeing inside, regardless of its fate.

[bitseeker]

   And here's the family portrait... 3 generations of 546xxx scope! 

Wow! Congrats on that CRT surviving. Those scopes look great!

I got an HP 54601A a few years back and a year or so afterward scored a 54657A Storage & GPIB module for it that adds FFT. Unfortunately, I need to upgrade the firmware in the scope to use it and haven't succeeded in finding one that's version 2.2 or higher.

Oscilloscope Compatibility

54657A and 54658A These modules are compatible with all Agilent 54600-series oscilloscopes except 54600A, 4601A, and 54602A oscilloscopes with an operating system version lower than 2.2. If your 54600A, 54601A, or 54602A oscilloscope has an earlier operating system, it can be updated using upgrade kit HP part number 54601-68702.

---------------

Update: Well, a new search found this post with info on the last version made, but the image file attached is version 2.0. Same as my scope has.

https://www.eevblog.com/forum/testgear/agilent-54601a-oscilloscope-eprom-firmware-needed/msg4051633/#msg4051633

Well, fuck-a-doodle. My 54657A RS-232/Math & Acquisition Module54600A came with the 54600A attached; that must have the correct firmware.

*runs down to the dwagon-cave to check*   

Any of you HP boffins know if the FW from the 54600A is the same as the 54601A? Only difference is the two extra channels, right? Maybe a bit flipped somewhere selects between the two?

https://groups.io/g/HP-Agilent-Keysight-equipment/topic/hp_54601a_os_update_possible/31819171

Oh, here we go... This post suggests that HP Upgrade Kit 54601-68702 is a preprogrammed EEPROM, so should be the same FW for all applicable scopes.

Hmmm... I see a programmer project in the works... 

mnem
*toddles off to make breakfast*

Yes, the manual lists the same part number for the update to all three models affected. So, they should all be the same.

[bitseeker]

   And here's the family portrait... 3 generations of 546xxx scope! 

Wow! Congrats on that CRT surviving. Those scopes look great!

I got an HP 54601A a few years back and a year or so afterward scored a 54657A Storage & GPIB module for it that adds FFT. Unfortunately, I need to upgrade the firmware in the scope to use it and haven't succeeded in finding one that's version 2.2 or higher.

Oscilloscope Compatibility

54657A and 54658A These modules are compatible with all Agilent 54600-series oscilloscopes except 54600A, 4601A, and 54602A oscilloscopes with an operating system version lower than 2.2. If your 54600A, 54601A, or 54602A oscilloscope has an earlier operating system, it can be updated using upgrade kit HP part number 54601-68702.

---------------

Update: Well, a new search found this post with info on the last version made, but the image file attached is version 2.0. Same as my scope has.

https://www.eevblog.com/forum/testgear/agilent-54601a-oscilloscope-eprom-firmware-needed/msg4051633/#msg4051633

Well, fuck-a-doodle. My 54657A RS-232/Math & Acquisition Module54600A came with the 54600A attached; that must have the correct firmware.

...

Oh, here we go... This post suggests that HP Upgrade Kit 54601-68702 is a preprogrammed EEPROM, so should be the same FW for all applicable scopes.

Hmmm... I see a programmer project in the works... 

mnem
*toddles off to make breakfast*

KO4BB has 54602A/B imges
http://www.ko4bb.com/getsimple/index.php?id=download&file=HP_Agilent/HP_54602AB_Firmware_ROM_images_EPROM_54600-8000812-29.zip

Don't know what revision though.

Yeah, that might do it. The final ROM version was 3.2 and had part number 54600-80013. There are three images in that zip with part numbers ending in 80004, 80008, and 80012. The 80008 was for the 54602A and the 80012 for the 54602B. So, one of them might work. Thanks, Robert!

[bitseeker]

The B&K Precision 2120 is back together. Resistance check of all the PSU voltages before applying power. No shorts.

For those expecting magic smoke sorry to disappoint you. The scope came right up without any issues. The +140V is adjustable. No adjustment needed. The only other adjustable voltage is the HV (-2kV). Will check that later.

Awesome! Keeping fingers crossed it survives Papa Smurf's burn-in. Then we know it's good.

[bitseeker]

Oh, here we go... This post suggests that HP Upgrade Kit 54601-68702 is a preprogrammed EEPROM, so should be the same FW for all applicable scopes. Hmmm... I see a programmer project in the works... 

KO4BB has 54602A/B images:
http://www.ko4bb.com/getsimple/index.php?id=download&file=HP_Agilent/HP_54602AB_Firmware_ROM_images_EPROM_54600-8000812-29.zip

Don't know what revision though.

That archive contains three .bin files evidently corresponding to the HP Part numbers for the ROMs back when they still supported these scopes: HP54658-80004, 54600-80008, and 54600-800812. I'd guess by the numbering that the first one is for the HP 54658 Serial/Math module (Maybe more, I dunno), while the latter two are for the 5460xx family scopes.

This post on eevBlog suggests that the latest FW is ROM Ver 3.2, HP Part number 54600-800813.

Based on that, 54600-8000812 might still be Version 3.x; but should still be at least as high as 2.3 which is on my 54600A.

Bitseeker, I think that's a better path than hoping I'll get far enough in the repair queue to actually extract the FW from my old dawg anytime like... before I die.

mnem
old tinkerdwagons never die; they just smell that way.

Yes, indeed. And I should know by now to catch up on reading before replying.

[EEVblog]

Meanwhile, in a Facebook vintage electronics group, these photos were posted today of this person's collection of meters and test gear, impressive or what?

The Excavatoree of analog!

[bitseeker]

Guys, stop posting crap that is completely unrelated to Electronics!

Wow! Such animosity toward TEAngents. Maybe it's better not to have this thread pinned. Too much visibility draws trouble like we've not experienced before.

[bitseeker]

Message to gnif. The calculator discussion is important. This is essential test gear meme material as well in this thread. Please don’t delete as its not off topic.

It seems the application of what is or is not OT is arbitrary and somewhat heavy handed just as some have feared. One of my posts today was deleted and it was basically an inquiry of what was posted prior and that original post remains present. Apparently what is or is not off topic going forward is going to be a moving target and purely discretionary and you won't know if you crossed the line until you get whacked like I did. 

I guess being one of the largest and most active contributor to TE content on this thread carries no weight, does it?     

I dunno perhaps we should charge for our contributions after all the key metric in this ecosystem is attention dynamics and not content 

Ferengi mode off.

Well, we are playing in someone else's playground. Arbitrary or not, we'll have to try to abide by their wishes as best we can. Before we became famous, life was easier and people didn't get bent out of shape about banter and getting to know one another. 

[bitseeker]

Meanwhile, in a Facebook vintage electronics group, these photos were posted today of this person's collection of meters and test gear, impressive or what?

The Excavatoree of analog!

Indeed! Well, someone's got to do it. TEA happens all over the place, not just in this thread.

I don't think my marriage could survive such an awesome collection of meters!

[Saskia]

Some assorted pinball spare parts due to roll in today or tomorrow. Will want to obtain acrylic mods to protect the plastics from breaking again as I do not intend to take it apart again anytime soon.
Also found a suitable topper for the STTNG. It's from BlueBrixx.
https://www.bluebrixx.com/de/bluebrixxspecials/104184/Star-Trek-USS-Enterprise-NCC-1701-D-BlueBrixx-Pro

Along with some Hallmark STTNG xmas tree illuminated gizmos to replace the meh (as in would need replacement, but do not look that great) ornaments ...
Minor mods you could call them. Will post continuation of the pinball journey in a new thread when I have time to actually do so.
This week end it will be:
overdue tax declaration
hunting down solar installers
looking for some panels to do a test install.
try to locate a battery that will take a 12VDC charge from a Solar panel inverter that has a charge controller built in (I got that for like 150€,
it's this one: https://www.reichelt.de/solar-wechselrichter-12-vdc-230-v-ac-1000-va-1000w-gc-invsol01-p325640.html )

Currently looking into HM-1500 from Hoymiles.

[Robert763]

I loved microdrives! Well, not to store information, but the same way some people love auto-wind wristwatches. Tiny electromechanical enginerdery just for the sake of being tiny!

mnem
...and it has nothing to do with the fact I made a freaking mint fixing microdrive-equipped iPods back in the day...

The microdrives being referred to are the dread Sinclair microdrives

   I suspect you're referring to something else. 1" HDDs?   

What the actual fuck... am I looking at? Is that a looped reel tape cartridge of some sort...? In what universe is that "micro"...?

I'm sorry... I have never ever seen this technology before. Did it maybe die the ignoble death it deserves before ever escaping your shores...?

mnem
mom: "You learn something new every day."
me: "Sometimes what you learn... is something better left unknown."

Oh it was micro, 44 mm × 34 mm × 8 mm (1.73 in × 1.34 in × 0.31 in) including protective cover and had a 5-metre (200 in) endless loop of magnetic tape, 1.9 mm (0.075 in) wide.
picture from https://commons.wikimedia.org/wiki/File:ZX_Microdrive,_opened,_compared_to_compact_cassette.png

[Squarewave]

Meanwhile, in a Facebook vintage electronics group, these photos were posted today of this person's collection of meters and test gear, impressive or what?

Niiiiiiiiiiiiiiiiiiiiiiice.

I like collecting the rare Avos. Think I have most of them apart from the first ever one made.

Wow, thats a fair few meters you have then, I have 4 fully working ones and somewhere in my pile I have a parts mule. I don't have enough room or since I retired, enough bread to collect much more unless I'm extremely clever at ferenging, which I'm slowly getting better at. 

It is a lot, admittedly too many! Many of the models I have more than one of and the different variants of them. Such as the Avometer Model 8 Mark 5, the regular one, the NATO version, the Post Office version.........

[Specmaster]

I loved microdrives! Well, not to store information, but the same way some people love auto-wind wristwatches. Tiny electromechanical enginerdery just for the sake of being tiny!

mnem
...and it has nothing to do with the fact I made a freaking mint fixing microdrive-equipped iPods back in the day...

The microdrives being referred to are the dread Sinclair microdrives

   I suspect you're referring to something else. 1" HDDs?   

What the actual fuck... am I looking at? Is that a looped reel tape cartridge of some sort...? In what universe is that "micro"...?

I'm sorry... I have never ever seen this technology before. Did it maybe die the ignoble death it deserves before ever escaping your shores...?

mnem
mom: "You learn something new every day."
me: "Sometimes what you learn... is something better left unknown."

Oh it was micro, 44 mm × 34 mm × 8 mm (1.73 in × 1.34 in × 0.31 in) including protective cover and had a 5-metre (200 in) endless loop of magnetic tape, 1.9 mm (0.075 in) wide.
picture from https://commons.wikimedia.org/wiki/File:ZX_Microdrive,_opened,_compared_to_compact_cassette.png

There was however a better offering from Rotronics, called a Wafadrive which had 2 built in tape drives, yes another endless tape loop but was thicker tape than the microdrive so was more reliable. This unit also managed to provide another ZX Spectrum expansion port, RS232 and a Centronics port as well, so offered much more bang per buck. I still have one of these devices, however have not used it or the Spectrum in over 20 odd years, so may not work any longer. Its fate, like that of the microdrive, was doomed through the lack of support from software developers, who preferred the cheaper but slower medium of cassette tapes.

[tautech]

If you’ve got some E12 resistors you can add a 3db at each end using a DIY pi attenuator. 270 ohms in series and 18 in each parallel element. That’s 49 ohms and 3.08dB which is close enough 

Well yes I could conjure up that with some 0805 SMD components ..........

Just finished and at 22.40 only time for a quick test as need be up early to take the chief cook and bottle washer to hospital for an op tomorrow. Sorta serious but apparently straight forward so batching for a couple days until I get the call to collect her.

Anyways closest I had was 20pF 0805's so it won't be perfect but all going well should get these crystals buzzing.

After much shagging around .....mind was on how wifey op was going....I finally got some ~20MHz buzz from the thing however this homemade fixture needs some tweaks based on what I been reading up on.
This was with SNA5kA as I needed to get closer to this new honey to better know how to twiddle her knobs. 

Sad how much spare time you have when the wife is away.....
Even some time for a fiddle with the DIY 'not quite right' Through fixture on SVA1032X with the same 20 MHz crystal this time with a touch of Phase thrown in. 

[tggzzz]

I loved microdrives! Well, not to store information, but the same way some people love auto-wind wristwatches. Tiny electromechanical enginerdery just for the sake of being tiny!

mnem
...and it has nothing to do with the fact I made a freaking mint fixing microdrive-equipped iPods back in the day...

There may be some confusion here. The Sinclair Microdrive came out in 1983, a bit before iPods. It was an alternative to floppy discs. I recall they had a continuous tape loop. Hard drives were an impossible luxury for owners of microcomputers back then.

It was advertised and people paid for them and had to wait about six months for them to turn up. When they turned up, they were slow and not very reliable.

http://retro8bitcomputers.co.uk/Sinclair/ZXMicrodrive

Yes, a continuous tape loop. Lots of lovely rubbing between layers.

I was in Cambridge at the time, and was vaguely acquainted with someone on the team developing them. ISTR they ran into Sinclair's requirement to remove a resistor if it continued to (apparently) work after the resistor was removed.

There are good reasons why I only bought one Sinclair product to use it, the Scientific calculator. His reputation was well deserved, based on a couple of decades evidence.

I have got a couple of bits of Sinclair test equipment (scopes, frequency counter), but only for fun, not use.

[Robert763]

According to Royal Mail my £100 professional 1.1GHz portable spectrum analyser with 6.4" VGA touchscreen will be delivered today.
Apparently they upgraded it to 24h delivery because they didn't pick it up when they were supposed to.
Pics soon.

[med6753]

The 2120 is back in the case and will be on burn-in for a few days. The compensation was pretty much OK with some minor adjustments. The noisy channel switch attenuators have improved more with use but I don't think they will ever be 100%. That would take a full tear down and removal from the board and disassembly of the decks. Then a full tarnish removal routine. It's not worth that amount of effort.

I don't expect any issues with a burn-in so I'm tentatively calling this project complete.



My repair/project cue for now is all caught up. The 3rd Type 547 is awaiting the HV transformer repair which may not be complete until the end of the year. So unless something appealing on Ebay shows up my TE activity for now is pretty much at a stand still. And given all the scrutiny lately from Admin and the insistence of on topic discussions only my further participation in this thread will be minimal. If I don't have TE material then I won't post. As simple as that. I don't relish being on Admin's radar and seems apparent I am. I'll still be around and checking in but that's about it. And of course if someone needs intervention and items shipped across the pond Papa Smurf's Shade Tree Export Service is still in business and ready to help.

What Admin doesn't understand is that this thread over the years has turned into a community of individuals with the same common interest but with diverse backgrounds. So naturally we want to understand each other which involves OT discussions of our lives and other interests. And so sometimes we wander off but always come back to topic. But now we've been told to keep it to electronics only. OK....understand what that means. The following items can no longer be discussed:

My continued journey with controlling diabetes.
Vince's new job.
BD139's impending move.
BU508A's love of baking sweet treats
Cubdriver's kitty cats.
Cerebus' quick wit.
I could go on. You get the point.

It's gonna get pretty boring in here.   

[tggzzz]

Even after all these decades of using calculators with an = key, after about 10 minutes using RPN, it just went "click". I totally get it!!

I like the mentality of gathering all the operands, then operating on them. In the same way I gather all the components on my desk, and only then start soldering them into the circuit.

And that's totally why RPN works. I realised very quickly that using RPN is actually the way we were taught to do things at school. You wrote down the first operand, then wrote the second one underneath it and the operation you were doing to the right of that. Then you proceeded to apply your operator to the rows and columns of digits, writing down the answer underneath.
Not an = sign in sight!

All the glory of RPN ends when you have to process large formulas with a lot of bracketed terms and you need find a way inside out and not left to right. RPN ist a way of misusing a human brain as stack memory. Humanity invented compilers to avoid that.

Algebraic notation is equally abusable. Some people seem to insist on using technology in a way that is more difficult than necessary/desirable.

But back to TE. Forth is a good option for embedded scripting languages inside TE: minimal size, complete, expandable.

Back in 1983 I spent a couple of days (only!) hacking a very simple such thing together, to peek/poke registers in some test equipment I was developing. It worked and was sufficient, but I realise that if it ever needed to be enhanced, Forth would be a better option. It made me realise that scrotty little home-grown Design Specific Languages are almost always a mistake - and that opinion has been reinforced several times in the following years. Much better to have a Design Specific Library in a standard language.

Nowadays MicroPython might be a sensible alternative; I believe there can even be one in the ESP8266s. I haven't investigated it, because having used makefiles and pretty-printers, I have a pathological aversion to anything where whitespace has semantic significance.

LUA might be another alternative; there is/was one for the ESP8266.

[tggzzz]

Meanwhile, in a Facebook vintage electronics group, these photos were posted today of this person's collection of meters and test gear, impressive or what?

Impressive, yes. But then so is a bunch of fives.

I think we can guess what tool that addict either couldn't afford when doing their first homebrew electronics, or used professionally in their first job.

[bd139]

If you’ve got some E12 resistors you can add a 3db at each end using a DIY pi attenuator. 270 ohms in series and 18 in each parallel element. That’s 49 ohms and 3.08dB which is close enough 

Well yes I could conjure up that with some 0805 SMD components ..........

Just finished and at 22.40 only time for a quick test as need be up early to take the chief cook and bottle washer to hospital for an op tomorrow. Sorta serious but apparently straight forward so batching for a couple days until I get the call to collect her.

Anyways closest I had was 20pF 0805's so it won't be perfect but all going well should get these crystals buzzing.

After much shagging around .....mind was on how wifey op was going....I finally got some ~20MHz buzz from the thing however this homemade fixture needs some tweaks based on what I been reading up on.
This was with SNA5kA as I needed to get closer to this new honey to better know how to twiddle her knobs. 

Sad how much spare time you have when the wife is away.....
Even some time for a fiddle with the DIY 'not quite right' Through fixture on SVA1032X with the same 20 MHz crystal this time with a touch of Phase thrown in. 

Took me about 2 hours to write this reply between fires 

That's actually looking like a pretty decent output 

Can you plot the total impedance magnitude on the left vs the frequency? Usually inductive up, capacitive down. That's probably the most useful plot for crystals.

There's a lot of confusing misinformation about series and parallel resonance so I'm deferring to the only useful answer I've ever found on stackoverflow:

https://electronics.stackexchange.com/questions/413054/confusing-quartz-crystal-impedance-graphs

Note the shift on resonance when adding the load capacitor.

[mansaxel]

I think we can guess what tool that addict either couldn't afford when doing their first homebrew electronics, or used professionally in their first job.

That 100% fits in with my addiction. Yes, I have scopes and Avometers. Just because.