Test Equipment Anonymous (TEA) group therapy thread

[Robert763]

A stack of button or coin cells s the common fix. I have some genuine Ever Ready BLR121s that while the same rectangular size and shape as the original it is mostly empty space with a stack of buttons down the middle.   

[McBryce]

Anyone looking for a portable Tek scope. The 200 series come up quite often, but I've rarely seen the 300 series on offer: https://www.ebay.de/itm/324687056177

McBryce.

[mindcrime]

- People suggested using explosives to solve some simple issue.

I mean, c'mon... a little Semtex never hurt anybody, and when you have a case that doesn't want to open any other way, what are ya gonna do???

- 30% of posts were completely off topic and had nothing to do with TEA.

Only 30%? 

[med6753]

Well gee, I sleep late today and look what the cat dragged in. 

Welcome back bd. 

[Brumby]

Indeed, welcome back BD.  Your absence was noted!!


Now your presence will be.

[mnementh]

Good morning all. I finally return! Going to take a few days to catch up. Literally 63 pages of posts since I last looked.
(SNIP)
Missed you all and glad to be back 

Welcome back, ya cantankerous ol' reprobate! The TEA has been entirely too quiet widdout-chya!!!

mnem
Pay no attention to the gargoyle in the corner... he's supposed to leave once his vigil is over...

[Cerebus]

OCXO test fixture board converted to 4 layer and now in the hands of JLCPCB.

Now the waiting begins...

Edit: Just got the "in production" email which either means it was a very clean design and they understood everything OR they didn't really check it and therefore it's guaranteed that I've done something stupid like told them the power and ground planes were the top and bottom, and the top and bottom planes were the inner planes. (BTW Thank God for DRC, I almost plotted the Gerbers with one power connection left unmake.)

[25 CPS]

over the weekend attended my first hamfest in a year and a half.  took a pledge not to purchase anything.

but the damn hobo's were selling meters for 5 bucks a piece.  (and the calculator was just too damn ugly to resist).

was in the truck heading home before it hit me.........fecking 22-1/2 volt batteries.  where am i gonna' find those?

I'd have broken that pledge too with those Simpson meters at that kind of price.

Holy crow, going to hamfests and buying things?  We're still almost completely locked up, up here.  It's insane.  The politicians keep moving the goalposts and better days are always around the corner but they're never here and we aren't allowed to have our lives back no matter how many vaccines get shot into people.  I'm done with it.

[Cerebus]

The problem with the whole Covid thing is that at the beginning all the politicians were too bloody slapdash and devil-may-care about the whole thing, and even when they actually got off their backsides and did something they mostly did the wrong thing. Thanks to that there's a big pile of bodies that at sometime, someone is going to demand a proper explanation for. "A week is a long time in politics" said Harold Wilson, and while it's unnervingly easy for politicians to dodge blame for something that happened weeks or months ago, they know that they can't dodge something that happened this week. So now they've swung the other way and are being ultra-cautious because any more avoidable deaths at this point are going to draw even more adverse scrutiny.

[Cubdriver]

over the weekend attended my first hamfest in a year and a half.  took a pledge not to purchase anything.

but the damn hobo's were selling meters for 5 bucks a piece.  (and the calculator was just too damn ugly to resist).

was in the truck heading home before it hit me.........fecking 22-1/2 volt batteries.  where am i gonna' find those?

Nice shiny battery here  https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3590046/#msg3590046

Couple of cheapish 3S Lipo's wrapped in a fake box would do it for not a lot of $. Nice low self discharge for occasional use and adding a cheap LiPo/mixed charger if you don't have one in the kit is a good toy to have.

not sure 2 lipo's will fit in the meter.  this is like the dead one that came out of the 269.

https://brooklynbatteryworks.com/eveready-412-22-5v-140mah-carbon-zinc-battery/

Ok baby one. Plenty of baby indoor R/C ones if you have a bit of a search. Hyperion are generally way better than the average swill on offer. eBay auction: #324673897656 maybe a pair of these?

oh......hey.....that might just work

will have to make some measurements of the battery space.

thanks!

I'm keeping an eye on this, too - I got one of those a few years ago.  Cleaned it up and took pics, but haven't uploaded them.  It looks cleaner than this now:


It has an interesting ladder chain drive to couple the range knob dos down in the corner to the switch in the center of the meter.

-Pat

<edit - dammit, I typed this on  a REAL keyboard - how the hell did I get 'dos' instead of 'down'?!?>

[mnementh]

Holy crow, going to hamfests and buying things?  We're still almost completely locked up, up here.  It's insane.  The politicians keep moving the goalposts and better days are always around the corner but they're never here and we aren't allowed to have our lives back no matter how many vaccines get shot into people.  I'm done with it.

Ummm... yeah. All I have to do is look at the stats up here vs those in the Petri Dish States down South and I'm actually thankful they're inconveniencing so many of us.

You can't have "business as usual" and actually take some reasonable precautions; you have to choose one or the other. This is still a fucking pandemic; even tho we are just now starting on the downhill side, it will still be more than a year before it is anything even marginally approaching safe to interact with other people as we used to consider it "normal" to do.

mnem
 

[Robert763]

So my sub £50 National Instruments GPIB-USB-HS interface arrived today, very fast shipping
Knowing that the versions of NI 488.2 >about 15 can detect fakes and won't work with them (not sure if it bricks them) I installed ver. 20 and hoped for the best. It reccognised the interface and serial number and all is good 
I interrupted chores, painting which I hate, up a ladder which I not that happy about when it can't be tied off or I don't have a competent "footer" to check the interface it so no time to actually connect to an instrument.
Can't complain for 1/2 the price of a cloned one that you have to find an old version of software for.

[mnementh]

There goes the neighbourhood!

Says the one, who is wearing occasionally stockings. 

"The one"...?



LOLOL...



mnem
*enjoys a night at the drag races as much as the next dwagon*

[mnementh]

over the weekend attended my first hamfest in a year and a half.  took a pledge not to purchase anything.

but the damn hobo's were selling meters for 5 bucks a piece.  (and the calculator was just too damn ugly to resist).

was in the truck heading home before it hit me.........fecking 22-1/2 volt batteries.  where am i gonna' find those?

Good lord... a on-topic post.  is a-mattah widdjoo...? bd is back; we all aspoda be talkin' aboot him!!!

mnem
... and not just behind his back when he izzn't lookin'.  

[mnementh]

Dumped 24,500lbs (just over 6 cu yards) of 4000psi mud down the hole.  Should have the big stick vertical maybe as soon as late next week.  Deputy inspector took 5 samples, going to test at 7 days and 28 days.  The inspector expects the 7 day test to yield over 3000psi and since the spec calls for 3000psi, Ill be good to mount the tower.

Ooooh.... lookit those nice juicy ground straps/backplate. Well done. 

mnem
You are gonna solder that shit after the inspection is done, right...?

[mnementh]

over the weekend attended my first hamfest in a year and a half.  took a pledge not to purchase anything.

but the damn hobo's were selling meters for 5 bucks a piece.  (and the calculator was just too damn ugly to resist).

was in the truck heading home before it hit me.........fecking 22-1/2 volt batteries.  where am i gonna' find those?

Nice shiny battery here  https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3590046/#msg3590046

Couple of cheapish 3S Lipo's wrapped in a fake box would do it for not a lot of $. Nice low self discharge for occasional use and adding a cheap LiPo/mixed charger if you don't have one in the kit is a good toy to have.

not sure 2 lipo's will fit in the meter.  this is like the dead one that came out of the 269.

https://brooklynbatteryworks.com/eveready-412-22-5v-140mah-carbon-zinc-battery/

Ok baby one. Plenty of baby indoor R/C ones if you have a bit of a search. Hyperion are generally way better than the average swill on offer. eBay auction: #324673897656 maybe a pair of these?

oh......hey.....that might just work

will have to make some measurements of the battery space.

thanks!

LiPos in an instrument that sits on a shelf unused for months or years at a time is not a great idea. Puffy death LiPos is a whole new failure mode that wasn't even dreamt of when these were designed.

I'd suggest 5 14500 or 16340 cylindrical cells with a 5S BMS/charging board, will produce 18-21V depending on state of charge and be much safer to leave inside an instrument.

Alternately, could get a cheap MOSFET Tab-welder (aboot $20-30 on eBay or less on banggood) and build a pack out of CR123A lithium primary cells that would have a shelf-life of a decade plus.

mnem
 

[mnementh]

   ... - I'm still slowly battering my way through the GPSDO prototype.

Things go slowly when a test run is, at the very minimum \$60 + \sum\limits_{n=0}^{9} 2^n \$ seconds. I've had hassles with noise on the analogue side of things, and signal integrity issues but I think I have those all licked. I'm just running up a board with just the analogue bit on (and nice coaxial test points) to give me one last confirmatory pass at the analogue side before I get the full mixed signal board spun up. It also will give me a chance to easily try all the OCXOs I've got sitting around  and grade them (I've got some discrete single pin sockets that I'm fabricating a socket for the OCXO out of).

Currently looks like this. I'm just in the middle of converting it from two layers at £1.43 to four layers at £5.73, because at those prices why wouldn't you go 4 layer?

Looks much tidier than my little perfboard version. 

That reminds me; I totes need to revisit that sometime and actually look at the signal. 

mnem
Dammit... now I'm actually on-topic... curse you freqq!!! 

[Cubdriver]

Just labeled and uploaded a few of the Simpson pictures.

Meter assembly after cleanup:


Range switch drive:


Range switch:


Cool old meter.

-Pat

[Cubdriver]

LiPos in an instrument that sits on a shelf unused for months or years at a time is not a great idea. Puffy death LiPos is a whole new failure mode that wasn't even dreamt of when these were designed.

I'd suggest 5 14500 or 16340 cylindrical cells with a 5S BMS/charging board, will produce 18-21V depending on state of charge and be much safer to leave inside an instrument.

Alternately, could get a cheap MOSFET Tab-welder (aboot $20-30 on eBay or less on banggood) and build a pack out of CR123A lithium primary cells that would have a shelf-life of a decade plus.

mnem
 

Definitely something to consider - will look into that.

-Pat

[Cerebus]

That reminds me; I totes need to revisit that sometime and actually look at the signal. 

That's precisely why I'm spinning up a board with lots of ground plane and mcx connectors to get the signals out through. There's so much electronic hash around here that looking at the DAC output and EFC inputs on both the 'scope and the "very slow scope" aka the Agilent 34461A in trend plotting mode shows way too much noise. From the performance I'm getting time and frequency wise I think that noise is just a measurement artefact. Basically, my current breadboard lashup is not conducive to good probing technique and has way too many unintentional loop antennas. So, decent board, lots of coax, and probably a biscuit tin are required to give me the warm fuzzies (or discover actual real problems) before I put the thing to bed in final form.

[Saskia]

  eBay classified works while in the hospital.

Got an external Dolby c for my Revox B77, will hopefully get 2 working technics ribbon tweeters, both measured at 5.5 ohms, i . e. Ok to be sent to hubby. When I get back I'll have a closer look at my Reichelt loot which includes a GW instek 4343 PSU and a Peak tech P4060 AWG (-160 MHz).
Will also pick up a Revox A77 w/ Dolby for my boss.

I can get one additional A77, if anyone wants one.

[med6753]

Strumming fingers and stamping foot waiting for FedEx to show you with my parts. Unlike UPS I can never predict when they will show up.

One critical part needed to remove the external 100V supply and restore the internal supply. 

[mnementh]

LiPos in an instrument that sits on a shelf unused for months or years at a time is not a great idea. Puffy death LiPos is a whole new failure mode that wasn't even dreamt of when these were designed.

I'd suggest 5 14500 or 16340 cylindrical cells with a 5S BMS/charging board, will produce 18-21V depending on state of charge and be much safer to leave inside an instrument.

Alternately, could get a cheap MOSFET Tab-welder (aboot $20-30 on eBay or less on banggood) and build a pack out of CR123A lithium primary cells that would have a shelf-life of a decade plus.

mnem
 

Definitely something to consider - will look into that.

-Pat

LOL.... yeah, I considered what I said after I said it... and then went & bought that damned tab welder (plus some anodized aluminum blingy bits for my new RadioMaster RC transmitter) as it was only ~$US14 with upgraded 10-15 day shipping. Can't hardly get the MOSFETS on the board for that, plus this is one of the better rated ones, as long as you feed it with enough current/heavy enough wire that the MOSFETs don't blow up from ringing. There's a wealth of knowledge on them if you read through the comments/reviews on the banggood listing page.



mnem
*more cheap Chinese tools for half a pittance*

[Cerebus]

I can get one additional A77, if anyone wants one.

Tempting, but I'll pass. If I was foolish enough to lumber myself with a 1/4" reel-to-reel recorder I think I'd have to go the whole hog and get a Studer A80 (of which I have fond memories) - along with a box full of mint 2N3055s for the inevitable regular replacements needed for the motor drives.

If you think Med's got floor loading problems with his Tek collection, wait until you see what a collection of professional tape machines would do to your joists. A 1/4" A80 comes in at 50kg in its most minimal form, add the usual cart and meter/amplifier bridge and it's got to be north of 100kg. The 2" 24 track version has got to easily be 200 kg or more.

[Cerebus]

Strumming fingers and stamping foot waiting for FedEx to show you with my parts. Unlike UPS I can never predict when they will show up.

One critical part needed to remove the external 100V supply and restore the internal supply. 

[Sings]

Strumming his clock with his fingers,
Wasting his life as he waits,
Med's waiting in vain for his p-arts,
Waiting in vai-n, for his parts,
Hoping it's Fed-Ex, on his drive,
But it's just the bill,
In the mail.

(With apologies to Roberta Flack)