Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Well, I found the issue and it's fatal. The +24.7V is shutting down because the Vertical Output IC on this board is NFG. 

Chances of swapping over that IC successfully without damaging it are pretty slim. So, I have no choice but to put the old board back in. Whoopie. 

But for now I'm taking a break. 

that's a shitter  . You know what the answer is though - you need ANOTHER 485 

I am looking out for a 2465 / 2445 as a "just in case scope". This is how it escalates. (no tggzzz yours are too expensive for my cheap arsery )

Nope, going to put the board back in a live with the slight overshoot on fast rise time pulses. It's not bad but anal me wanted to see if I could fix it. Sometimes I'm my own worst enemy.

So far the 485 parts mule has had a bad trigger IC, a bad tant, and now a bad vertical output IC. Somebody really beat the crap out of that scope. 

[bd139]

I am looking out for a 2465 / 2445 as a "just in case scope". This is how it escalates. (no tggzzz yours are too expensive for my cheap arsery )

Just out of curiousity: Why a 2465 / 2445? Do you need this bandwidth? And my understanding was, that size is important for you.
So, why not buying something small with 2 input channels with, let's say with a bandwidth of 100MHz?

For example a THS 720A:
https://www.ebay.co.uk/itm/174154132210

A cheaper one from Israel:
https://www.ebay.co.uk/itm/223829013652

And it has a DMM integrated.
It's a nice scope which I'm using for my "Reparier Bar" stuff. I've bought it some years ago at the HAM Radio in Friedrichshafen
for around 230 Euros, including two probes, new battery and the Tektronix hardplastic carrying case.

Edit:
I've checked some ended auctions on ebay and for Europe this was the cheapest I've found:

https://www.ebay.de/itm/TEKTRONIX-2465-Oszilloskop-300MHz-4-Kanaele-/333402089922

That's a nice one, coming with the DMM:
https://www.ebay.de/itm/Tektronix-2465-A-DM-350-MHz-/184055426003

Thanks for the links. Much appreciated 

I'm not too worried about the bandwidth TBH. Anything 100MHz or above is fine for me. The nature of the thing is that it has a half decent delay sweep system and cursors which are far more useful for measurements than other scopes. THS 720A is interesting as it's based on the same platform as TDS200 series which I have owned a specimen of and quite liked it. Also it has 100% isolated channels.

I will take a look at these

You know what they say: buy cheap, buy twice. Or is that an underestimate 

A vast underestimate. I had 11 cheap Tek scopes at one point 

hey bd

were you bitchin' a couple of weeks ago about a sweep problem in an hp 1740?

grabbed one of mine to look at some ttl stuff and discovered it was having sweep/retrace hiccups.

pulled the cover and found this note.  hmmmmmm.  that is my handwriting.  musta' put that note in there 15 or 20 years ago.

followed my instructions from the past (or maybe i am finally gonna' get around to that time machine and its from the future?).  it is now working a-ok once again.  most likely pushing at the top reseats that white connector waaaaaay down at the bottom of the board?

or did you already sell your only hp scope?     

That's quite funny to see inside something  . I think Specmaster had a 1740A with similar sorts of problems in the HT area.

As for my 1740A it's probably going now I have the 2245. It's vastly inferior and I'd rather have the cash on hand in case something else interesting appears 

I suspect, that bd can afford it to buy it right the first time. But then, where's the fun? If you are buying cheap the first time, chances are high, that you can buy it a second time (after you have sold the first one and stated, that you are done with it! Really! Honestly! This time for real!).   
Several months later ....   

As mentioned before it's sometimes about the journey and the wide experience you get from fixing broken things. I refer to:

https://doc.xdevs.com/doc/_Books/Jim_Williams_The_Art_and_Science_of_Analog_Circuit_Design.pdf

Chapter: "The importance of fixing"

Also to note I am diverting some of my budget to buying a rather expensive bicycle and half a new wardrobe at the moment so need to keep things "as tight as a duck's arse"

[BU508A]

I'm not too worried about the bandwidth TBH. Anything 100MHz or above is fine for me. The nature of the thing is that it has a half decent delay sweep system and cursors which are far more useful for measurements than other scopes. THS 720A is interesting as it's based on the same platform as TDS200 series which I have owned a specimen of and quite liked it. Also it has 100% isolated channels.

I will take a look at these

There is another one from forum fellow Mr. Ice-Tea, located in Belgium. It is the THS720P.
Quote from the auction:
"This is the "P" version, this unit also analyzes W, VA, VAR, V, A, THD-F, THD-R, PF, DPF, PHI which makes it perfect for mains related measurements."

https://www.ebay.co.uk/itm/143529974774

Ok, I know you are more interested in low-voltage stuff but I think for developing and building DC-DC converters it could be useful as well.

As mentioned before it's sometimes about the journey and the wide experience you get from fixing broken things. I refer to:

https://doc.xdevs.com/doc/_Books/Jim_Williams_The_Art_and_Science_of_Analog_Circuit_Design.pdf

Chapter: "The importance of fixing"

Also to note I am diverting some of my budget to buying a rather expensive bicycle and half a new wardrobe at the moment so need to keep things "as tight as a duck's arse"

Yes, I understand this.   But what is worth a journey without being a little bit teased by some TEA fellows? 

[capt bullshot]

On THS720 and TDS2xx:

I'm not too worried about the bandwidth TBH. Anything 100MHz or above is fine for me. The nature of the thing is that it has a half decent delay sweep system and cursors which are far more useful for measurements than other scopes. THS 720A is interesting as it's based on the same platform as TDS200 series which I have owned a specimen of and quite liked it. Also it has 100% isolated channels.

Having used both kind of species, except for the isolated inputs, the TDS2xx is a way much better choice over the THS720. The THS720 is slower (both in terms of UI lagginess and perceived waveforms per time), plus the TDS2xx has the knob per channel concept while the THS720 has the choose yer channel and then use a nasty up/down switch on this channel mode.
At least a THS720 can be converted to a THS730 by changing a single 0R jumper inside, giving you the 1Gs/sec instead of 500Ms/sec (analog BW doesn't increase by this mod alone).

[capt bullshot]

On THS720P:

One can easily convert a THS720A to an THS720P by changing an internal 0R jumper. IMHO it isn't worth that effort, since you need a decent current probe for this to be useful (that I have), but the additional functions are that laggy and slow I consider them pointless.

[BU508A]

While surfing around I've found this weird-looking scope from Metrix:

It is a Metrix MTX 3252 2 Channel 60Mhz Oscilloscope


https://www.ebay.com/itm/283474628268

Never saw one of these before. 

But when I looked at this scope, another one crossed my mind:
The scopes from Yokogawa (YEW), for example the Yokogawa DL1300A 100MHz digital scope.

This one comes with a printer too.


https://www.ebay.com/itm/293044805150

Has anybody worked with one of these scopes and can share one or two stories about them? Just curious how the perform and the handling is.

[capt bullshot]

On Yokogawa scopes:

Has anybody worked with one of these scopes and can share one or two stories about them? Just curious how the perform and the handling is.

We've got quite a bunch of them here (@work). Technically, they're quite performant and quality gear if you consider the vintage of the particular specimen. In contrast to the other major brands, they're not so well known as Keysight, Tek and Lecroy, but I'd consider them members of a similar class. I don't like them too much, because their UI is pretty much different from what you're used to by Keysight, Tek or Lecroy. A bit like a japanese high end stereo from the 80's.

[Cerebus]

But when I looked at this scope, another one crossed my mind:
The scopes from Yokogawa (YEW), for example the Yokogawa DL1300A 100MHz digital scope.

This one comes with a printer too.


https://www.ebay.com/itm/293044805150

Every time I see one of those Yokogawa scopes this comes to mind:



Except possibly with classic cartoon Asian slanted eyes.

[bd139]

Ahh github has just exploded in a ball of flames so slacking time 

Anything Japanese will have top notch hardware engineering but the software will be like grating your balls with a cheese grater then jumping in a bath of lemon juice. They just can't do software at all. It's always completely arse backwards and has layers and layers and layers of politics hiding in it that you can't see but are conspiring to turn you into Inejiro Asanuma.

That Metrix unit is weird. It looks like there was some weird backwards French "country internal" telecoms project which went under and they had a bunch of enclosures left that had to be used.

[mansaxel]

Is it normal for HP 3400A with input not connected, when switching the ranges switch, the meter's needle move to right most, and then rest back to zero at the left most ? It happens at every switching at every ranges. 

Yeah that's normal 

400E does it too.

As does the 427...

[RolandK]

Anyone in UK need a death-inator?

https://www.ebay.co.uk/itm/372957387420

(Hewlett Packard 6516A)

I'm tempted but I can't think of a legitimate use for it other than murder.

I would really like to buy it. But: Does not ship to germany, cant even ask the seller without UK address. Seems he does not want to earn money. Holly shit.

[tggzzz]

While surfing around I've found this weird-looking scope from Metrix:

It is a Metrix MTX 3252 2 Channel 60Mhz Oscilloscope


https://www.ebay.com/itm/283474628268

Never saw one of these before. 

Metrix does go "off-piste" with its form factors!

In general I don't particularly like pen-like handheld DMMs; they just don't work for me. However, I do rather like the MX-67 hand-held multimeter when noodling around a circuit, because the display is right where I want it: by the probe.

[bd139]

That DMM reminds me of this episode of Red Dwarf with the antimatter chopsticks:



zip to 2:28 for the fun.

Edit: decided I need an HP 6215A for charging small SLA batteries.

[BU508A]

Anything Japanese will have top notch hardware engineering but the software will be like grating your balls with a cheese grater then jumping in a bath of lemon juice. They just can't do software at all. It's always completely arse backwards and has layers and layers and layers of politics hiding in it that you can't see but are conspiring to turn you into Inejiro Asanuma.

HAHAHAHAHAHA! 

And I know the reason why. Because all talented software developer were absorbed by Sega, Nintendo and Co. 

[nixiefreqq]

Edit: decided I need an HP 6215A for charging small SLA batteries.

6215a is ok.  but my 6218a is better.  because sometimes you want to limit the smeggin' current.

[Cubdriver]

While surfing around I've found this weird-looking scope from Metrix:

It is a Metrix MTX 3252 2 Channel 60Mhz Oscilloscope


https://www.ebay.com/itm/283474628268

Never saw one of these before. 

That's certainly funky looking!!  I've never seen one either.

But when I looked at this scope, another one crossed my mind:
The scopes from Yokogawa (YEW), for example the Yokogawa DL1300A 100MHz digital scope.

This one comes with a printer too.


https://www.ebay.com/itm/293044805150

Has anybody worked with one of these scopes and can share one or two stories about them? Just curious how the perform and the handling is.

I've never seen one of those, either.  It's a cute little scope, but that interface looks even more user unfriendly than the one on the HP 1980B scope.  At least the 1980B still sort of groups the buttons into separate sub-panels by their function.  I'm not sure who came up with that interface, but "one knob to do everything as selected by one of many nearly identical looking buttons in a grid" is an operational nightmare.  Hell, I gripe at my Tek scope that has just one knob each for the four vertical attenuators and positions.

HP 1980B (still buried in my repair queue):


I'm glad that the 'one knob for everything' interface seems mostly to have gone the way of the dodo.

-Pat

[Cubdriver]

Edit: decided I need an HP 6215A for charging small SLA batteries.

6215a is ok.  but my 6218a is better.  because sometimes you want to limit the smeggin' current.

Agreed!  I much prefer the even-numbered variants of the 621xA series - use the current limit more often that I expected I might.

-Pat

[bd139]

Edit: decided I need an HP 6215A for charging small SLA batteries.

6215a is ok.  but my 6218a is better.  because sometimes you want to limit the smeggin' current.

Agreed!  I much prefer the even-numbered variants of the 621xA series - use the current limit more often that I expected I might.

-Pat

Good point. 6218A it is! Rarely ever appear here. I had one but it was smashed to bits due to bad packaging (jvincent120 the idiot on ebay for ref)

[nixiefreqq]

omg cub

the 1980b was a bridge too far for hp.

mine was a nightmare.   actually got it working once for about a year and it made me happy then to own it.

then spent about 4 years fixing it until the parts mules ran out of working bits and my frustration level pegged out.

finally took it to a hamfest and sold it to an hp addict for 10 bucks.  told him it was a basket case, but he wanted it anyway.

my guess is that he wanted the freq counter plug in.  hope it worked out for the guy.

my one knob hp 54502 and 54504 scopes still suit me just fine.  you get used to them.

[nixiefreqq]

Edit: decided I need an HP 6215A for charging small SLA batteries.

6215a is ok.  but my 6218a is better.  because sometimes you want to limit the smeggin' current.

Agreed!  I much prefer the even-numbered variants of the 621xA series - use the current limit more often that I expected I might.

-Pat

Good point. 6218A it is! Rarely ever appear here. I had one but it was smashed to bits due to bad packaging (jvincent120 the idiot on ebay for ref)

you might also consider the 6216a.  only 24 volts but the extra 200 ma might come in handy for battery charging.

[AVGresponding]

Mnem's bulking up !
How long will it last ?   

"Bulking up" With 20lb dumbbells?? That's just 9kg.

McBryce.

Depends how many reps you do. A couple of thousand per day should work!   


@bd139, that seller name rang a bell, and sure enough I have them on my saved list, though I can't for the life of me remember if I ever bought anything off them.

[mnementh]

IME, usually Manganin or Constantan wire is spot-welded to the leads or terminals; these are soldered. Once I have a chance to do a little cleanup, I may be able to confirm this. It is possible they made these shunts in-house exactly the same as several other similar precision resistors that are in the meter. If they're made with silver-bearing solder, that might explain the construction.

mnem
*really off to bed this time*

You should be able to solder manganin wire. You will need to remove any oxidization/coatings, then coat the end in flux, before soldering(quickly)

I wasn't saying that I couldn't; I was saying that the construction techniques used in these shunts (soldered, not welded) in a mass-production scenario suggests that a more easily soldered alloy was probably used. You can make a shunt out of any conductive material; I can't tell you how many I've made from a length of 12ga copper harvested from ROMEX and given a careful pinch or two to throttle them angry pixies.

Mnem's bulking up !   How long will it last ?   

"Bulking up" With 20lb dumbbells?? That's just 9kg.   McBryce.

You'd be amazed at what a difference just starting my day out with 5 trips up & down the stairs has made in how I feel the rest of the day... hauling three-hundred & mumblety-mumble pounds up & down 5 flights gets even my old stovepipe legs' attention and the blood a-pumpin'.

There's a lot more to doing a proper upper body workout than gross tonnage; you need both reps to fatigue at moderate loads AND "taxing to failure" loads to really bulk up and have muscle tissue you can put to work. Try holding a pair of 5-pounders at full extension in standing crane pose; you'll be crying in less than a minute. 

I've done this before; in high school I used to bench 250 and leg press a ton. My interest now is in finding an exercise regimen that doesn't load up my lower back injury but still cranks up my metabolism for weight loss. Maybe add a few endurance exercises to work the secondary muscle groups and loosen up the joints. My intent is to pair the 'bells with a leg curl bench so I can work both upper and lower body without compressing the injured sciatic region. I got these because a) they were exactly what I'd been shopping retail just a few weeks ago; $120 worth of traditional cast hex 'bells for $36 tax-free at the Sal. A total no-brainer. 

I'm finding that many of the techniques I used as a kid are not exactly good for an old fart like myself; but trying to glean useful information from the sea of "Health & Fitness Guru" bundahoo is a mental workout like none I've ever faced before. Last session I literally went to bed with a pounding headache from all the BS.

Somebody needs to take my credit card away...      Oh, and I bought a PS3 Slim just because it was complete for $25...   

mnem
 

More like someone needs a fidgit spinner, 3D Printer or their real existing toy collection back under their wings again. Just remember all this extra crap you are adding now will be combined with the other at some point in the future

Then comes another move to larger property to house it all and so the circle begins... again and again 

Actually, I've found a simple mostly painless solution for that as well. The Sal gives me a $10 coupon for any donation; I load all the leftover crap in a grocery bag (plus whatever SWMBO asks me to add) once or twice a week now. Anything I feel is worth more than $10 in component parts, I force myself to strip out for those components and recycle the rest. Engaging that mental construct has made me weigh the consequences of "junk collecting" much more carefully.

mnem

[alextwin007]

That little printer is adorable

But when I looked at this scope, another one crossed my mind:
The scopes from Yokogawa (YEW), for example the Yokogawa DL1300A 100MHz digital scope.

This one comes with a printer too.


https://www.ebay.com/itm/293044805150

[mnementh]

hey bd

were you bitchin' a couple of weeks ago about a sweep problem in an hp 1740?

grabbed one of mine to look at some ttl stuff and discovered it was having sweep/retrace hiccups.

pulled the cover and found this note.  hmmmmmm.  that is my handwriting.  musta' put that note in there 15 or 20 years ago.

followed my instructions from the past (or maybe i am finally gonna' get around to that time machine and its from the future?).  it is now working a-ok once again.  most likely pushing at the top reseats that white connector waaaaaay down at the bottom of the board?

or did you already sell your only hp scope?     

   Oh, man... that is priceless... an instant classic. Thanks for the belly laugh; I needed it. 


In Other News... I Hate Human Beings and Everything Associated With Them.

Well, that may be SLIGHTLY extreme... but dealing with things that people handle frequently is one of the tasks I loathe most in the world. Case in point: PS3 controller #1. Full of critter fur (how the FUCK does it get in there through gaps of 0.5mm anyways...?) stuck to every bit of foam adhesive so you have grab and pull it out... and for the sake of my own sanity I'm going to assume that the reddish-brown liquid which has pooled and dried in the bottom of this thing is in fact Jolt Cola and NOT blood. FUCKING FUCKITY-FUCK!!!

There's a reason I only buy keyboards that can be washed under the tap anymore...

mnem
One down, two more to go...

[mnementh]

Also to note I am diverting some of my budget to buying a rather expensive bicycle and half a new wardrobe at the moment so need to keep things "as tight as a duck's arse"

*sigh* I miss being able to tolerate bicycles. I keep telling myself I could maybe actually ride one of the fatbikes with a electric motor assist; but then I start looking at the whole e-bike rabbit-hole and I realize I'd never actually finish building... 

mnem