Test Equipment Anonymous (TEA) group therapy thread

[bd139]

Yeah we were middle class BBC Micro family. Sinclair was for scum 

My dislike for Sinclair started in the late 60s / early 70s, when he was peddling solder-it-yourself audio kits. They were infamous for not working. So were Scentific kits and his later "lacerated floppy" streaming tape drives.

By the time the ZX8x/Beebs had arrived, I'd moved to Sun 1s. The only Acorn thing I purchased (or rather got my company to purchase) was their System 1. With that I managed to do something in 3 weeks that other people thought would take 6 months.

I remember my father swearing at one of those kits. I got his hand me down ZX81 as well. He was the worst kind of cheap arse at best. He'd buy the cheapest thing out there then realise it was a chunk of poop and then buy the good thing. I didn't keep the ZX81. Sold it and bought a second floppy drive for the beeb.

Those microdrives were poo.

This has to be the best machine ever made. An Acorn RiscPC: http://www.john-ward.org.uk/personal/john/computers/html/rocket.html

Yes that extensible!

[Specmaster]

Yeah we were middle class BBC Micro family. Sinclair was for scum 

My dislike for Sinclair started in the late 60s / early 70s, when he was peddling solder-it-yourself audio kits. They were infamous for not working. So were Scentific kits and his later "lacerated floppy" streaming tape drives.

By the time the ZX8x/Beebs had arrived, I'd moved to Sun 1s. The only Acorn thing I purchased (or rather got my company to purchase) was their System 1. With that I managed to do something in 3 weeks that other people thought would take 6 months.

I had some Sinclair items and they were OK as long as you didn't take liberties with them. I had and still have somewhere in the garage I think, one of his scientific calculators that was still working last time I tested it about 2 years ago, although I hate that dreaded RPN system, that they use.  I had and still have a ZX Spectrum 48K computer, again still working but it did undergo a good deal of modification in its life. I added a proper full sized keyboard from a Memotech MX512, spectrum was fitted inside the keyboard, A proper 3.5" floppy disc drive and a parallel printer interface from the clever and brilliant company "MGT" Miles Gordon Technology in Cambridge.

I did word processing, databasing using a little known program called Masterfile from Campbell systems among other uses that were not what most people used their spectrums for, games, it was capable of far more than that alone.

[bd139]

Sinclair's version of RPN was cost optimised as was everything he did. Which is why it was poo. HP41 was faaaar nicer than anything else on the market. But more expensive. I was a user of HP calculators for many years.

Edit: dammit now looking on ebay for an HP-41CX

[Specmaster]

I have a few HP calcs in my repair / restore stack when I get round to them.

[mnementh]

That thing looks like a ZX81 had sex with a Philips scope.

Oh, but the real wonders can't be seen in a photo, they have to be experienced in person. Nothing beats fondling (or poking hard in this case), reading, and the subsequent bafflement followed by sheer annoyance.

But if you really want, a little googling reveals:

I WARNED you not to look too closely at it! Like the visage of Cthulhu, it shall surely drive you insane!!!

mnem
"That way lies madness."

That thing looks like a ZX81 had sex with a Philips scope.

I knew there was a good reason you could get keyboard condoms for ZX81s!

I had one... with the 16K expansion pack, parallel port riser and you guessed it - an Epson FX-80 (MX-80?) 9-pin printer. ASCII pr0n never looked so good! 

In a fit of aggravation, I spent a whole weekend rewiring a CHERRY keyboard (manually toning out and building the matrix switch by switch) onto it from one of the old NASTEC Case2000 workstations I had left over from recycling a police station. That of course did NOT help the pitiful workspace it had to offer, but it DID at least feel almost like a VIC20. 

mnem
Every time somebody says "ZX-81", somewhere a nerd feels an icy chill run down his spine.

[Vgkid]

My most expensive purchase in my lab is no longer my 34401 , but 3 0.1 ohm resistors. 

[xrunner]

Ah fresh RIFA! I love the smell of fresh RIFA in the morning - Does NOT burn like napalm.

New compared to old. I mean, I like distress cracks on antiques as long as it's furniture. 

[bd139]

Die RIFA scum!

Minor breakthrough this evening. Managed to get my RF PA to work without exploding on a mismatch! Got 25W out of a 50p FET. Woot. Not being buggered for £20 RF transistors.

Also found another issue with the BM867s. If it’s sitting in series with the PA monitoring current it goes bloody mental when you key down. Fluke, fine. Keysight, fine. Hmm. This is why I haven’t dropped my review yet. I still like it but not for that.

Edit: notably the carefully disguised DT830/Tenma unit I have also wasn’t bothered by the RF.

[Mr. Scram]

My most expensive purchase in my lab is no longer my 34401 , but 3 0.1 ohm resistors. 

Low key bench DMM brag.

[tautech]

Die RIFA scum!

Minor breakthrough this evening. Managed to get my RF PA to work without exploding on a mismatch! Got 25W out of a 50p FET. Woot. Not being buggered for £20 RF transistors.

Also found another issue with the BM867s. If it’s sitting in series with the PA monitoring current it goes bloody mental when you key down. Fluke, fine. Keysight, fine. Hmm. This is why I haven’t dropped my review yet. I still like it but not for that.

Interesting.
Joe Smith uses a mains demagnetizer to check meters stability and the Brymen didn't give issues where the Gossen was a POS without additional shielding.

[Specmaster]

@ tautech, I was just going to say the same thing, I use mine in the presence of RF generators upto 230 MHz with no problems at all, and in very close proximity some big arse mains transformers with zero effect on it. May be worth while reporting it to Brymen as he may have an issue with the shielding.

[tautech]

@ tautech, I was just going to say the same thing, I use mine in the presence of RF generators upto 230 MHz with no problems at all, and in very close proximity some big arse mains transformers with zero effect on it. May be worth while reporting it to Brymen as he may have an issue with the shielding.

It might be better to bring this to Joes attention so that he can run some tests.......RFI is a bit different to LF EMI.

bd139
Drop a post into this thread about the Brymen and I'm sure Joe will took into it.
https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/

[xrunner]

Also found another issue with the BM867s. If it’s sitting in series with the PA monitoring current it goes bloody mental when you key down. Fluke, fine. Keysight, fine. Hmm. This is why I haven’t dropped my review yet. I still like it but not for that.

Edit: notably the carefully disguised DT830/Tenma unit I have also wasn’t bothered by the RF.

What frequency range are we talking?

[bd139]

7Mhz. That’s 25W of RF. Enough to burn you (minor RF burn on finger from the LPF  ). I’ve got a Hammond box on the way from CPC. Will chuck it inside that and see if it’s radiation from the PA or up the feed. I haven’t stuffed an RFC on the DC inlet yet. This is very prototype phase stuff so I don’t want to piss on their party until I’m a good citizen

[Specmaster]

7Mhz. That’s 25W of RF. Enough to burn you (minor RF burn on finger from the LPF  ). I’ve got a Hammond box on the way from CPC. Will chuck it inside that and see if it’s radiation from the PA or up the feed. I haven’t stuffed an RFC on the DC inlet yet. This is very prototype phase stuff so I don’t want to piss on their party until I’m a good citizen

A good citizen!, with an unhealthy interest in blowing things up.......not likely to happen is it 

Maybe Brymen thought the chances of someone bunging out 25W at 7Mhz so close to their meter was highly improbable 

[xrunner]

7Mhz. That’s 25W of RF. Enough to burn you (minor RF burn on finger from the LPF  ). I’ve got a Hammond box on the way from CPC. Will chuck it inside that and see if it’s radiation from the PA or up the feed. I haven’t stuffed an RFC on the DC inlet yet. This is very prototype phase stuff so I don’t want to piss on their party until I’m a good citizen

7 MHz - that's weird because I have a laptop I use in the living room for digital (FT8) that has a touchpad that gets zonked on only one ham band - 40 m. Meaning the only thing that stops working is the touchpad when I xmit and after it gets zonked-out it will not work again until reboot. I've tried all the ferrite solutions to no avail - it's getting in through the case not the wires.

Seems 7-ish MHz is bad voodoo for electronics. 

[bitseeker]

The old Heath V-5 VTVM needed some TLC. The meter movement was dancing around with no input and even with the test leads shorted together. Checking quickly showed that the B+ was also dancing around. The filter cap that I had replaced about 20 years ago had gone leaky. So out with the 10uf/150V and in with a 15uf/150V. Stable now.

Yeah, I suppose one could say that it's due for a tune up. Looks right as rain, now!

[bitseeker]

W I N N E R !   

My DSO-X 3034A was delivered to Keysight today morning.

And yippie -dooo, I just got an email from Keysight: They do a repair and calibration service:


Price: none, warranty!      

_{TEA working back of my brain: Hmmm. Saved so much. Could consider purchasing all options, looking for special offers..}   

That's excellent! Congrats!

[bitseeker]

Ah fresh RIFA! I love the smell of fresh RIFA in the morning - Does NOT burn like napalm.

New compared to old. I mean, I like distress cracks on antiques as long as it's furniture. 

Cool. Are you working from GreyWoolfe's recent replacement parts list?

[med6753]

They must use the same software as the USPS. I once had the post office tell me a package would be delivered in the past. It turns out the package had the correct street address, the correct town, and the correct state but WRONG zip code. So it was sent to the post office of that zip code. When they found out they couldn't deliver it rather than taking 2 minutes to look up the correct zip code they instead returned it to sender as undeliverable. Freaking clowns.  But overall I have to say that the USPS does do a decent job....usually.

But this Hermes outfit sounds like a bunch of losers. Glad we don't have them here. Besides....."Hermes" sounds too much like "Herpes" which is something I don't want to catch. 

That you think "venereal disease" rather than "Greek god" tells me more than I cared to know about you.

Hey, what can I say? This uneducated, unwashed, and uncivilized colonist has no desire to study, learn, appreciate Greek mythology nor to chase unicorns. But I do appreciate the fine things that flitter around me with the understanding and awareness that those fine things can sometimes harbor nasty surprises. Now does that make me an undesirable and a dirty dawg? Only you can decide that. As for me.....WOOF!     

[xrunner]

Cool. Are you working from GreyWoolfe's recent replacement parts list?

Yes sir. Here they are again in case anyone needs to do this. I ordered double the amount, you know just in case I get an itchy Ebay finger. 

Manufacturers part numbers -

1000 pF  PME271Y410MR19T0 (2 required)
.022 uF  PME271Y522MR30 (2 required)

[GreyWoolfe]

Cool. Are you working from GreyWoolfe's recent replacement parts list?

Yes sir. Here they are again in case anyone needs to do this. I ordered double the amount, you know just in case I get an itchy Ebay finger. 

Manufacturers part numbers -

1000 pF  PME271Y410MR19T0 (2 required)
.022 uF  PME271Y522MR30 (2 required)

I love it when I am actually good for something instead of good for nothing!!

[xrunner]

I love it when I am actually good for something instead of good for nothing!!

Hey what's the status with your meter?

[URI]

My most expensive purchase in my lab is no longer my 34401 , but 3 0.1 ohm resistors. 

Nice!
Nor reason for from my point of view.   

I'd appreciate to see photos of them and perhaps how they measure with your 34401A.
Do you have plans to get them calibrated against NIST or something alike?
Any special treatment planned for them? Thermal control/stabilisation?

Is there an analogy to voltnuttery -like ohmsnuttery?      

[mnementh]

I think it all falls under the "standards-nuttery" umbrella.   

Cool. Are you working from GreyWoolfe's recent replacement parts list?

Yes sir. Here they are again in case anyone needs to do this. I ordered double the amount, you know just in case I get an itchy Ebay finger. 

Manufacturers part numbers -

1000 pF  PME271Y410MR19T0 (2 required)
.022 uF  PME271Y522MR30 (2 required)

*scribble-scribble-scribble*

7Mhz. That’s 25W of RF. Enough to burn you (minor RF burn on finger from the LPF  ). I’ve got a Hammond box on the way from CPC. Will chuck it inside that and see if it’s radiation from the PA or up the feed. I haven’t stuffed an RFC on the DC inlet yet. This is very prototype phase stuff so I don’t want to piss on their party until I’m a good citizen

RF burns are the worst... they burn life a mofo at first, so much worse than you would ever imagine from what you can see... then just when you can't bear it, the burning turns into itching so far inside there's no way to even get close to it... *cringes at just the memory of it*

I hate you now for reminding me. 

Also... "good citizen"... I can't believe you said that with a straight face.     

mnem
*about to punt my son's birthday laptop*