Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

IN OTHER NEWS:

I just survived building a bed. With my son's help. 

mnem
*toddles off to grill somethin'*

[exor]

I’m aiming higher. This has been used in broadcast measuring van. And it came with manual with all the instructions one may ever need.
Hope it will re-activate and even elevate my DXing 
If not, I can still use it for 10MHz frequency reference GPS antenna, 4G router antenna, weather station, … 

Been there, done that. Be carefull they can kill. One nearly got me.

Thanks for the warning. Lightning? Collapsed? Accidental retracting?

I'd imagine that a genuine risk with those is driving off after failing to retract it. Add almost any overhead structure, but especially HV power lines to "fire for effect".

The Range Rover had a pressure switch and a big IP67 microswitch (active if mast not fully down) in paralell. If either was active with ignition in RUN position you got a big reg LED lit on top of the dash. If handbrake was off you got a loud sonalert too. Compressor would not run with handbrake off. You could cancel the LED for night time operations with engine running for power but if anything changed state, including brake lights, it came back on. Insurance compamy (NFU Mutual) were OK with it as long as it passed the MOT. They did exclude the mast from the comprehensive cover too but 3rd party including hitting something with it was covered.

I will bolt mine (semi)permanently on a brick wall or big concrete slab in the middle of the garden so it won’t hit the road either erected nor retracted

[tggzzz]

I bet you're older than me, by quite some margin, but I love Avometers 

Yep, if you drop them, they're donald ducked, though the movements can survive, the casing will be shattered.

I don't love them, and have a couple of carcasses I will unload for a pittance.

Long ago I was working with GPO[1] Martlesham Heath and they told me of a "competition" between Avo 8 salesmen and  a DMM salesman. Everything was evenly matched until the DMM salesman picked up his offering, threw it across the room, and suggested repeating the competition.

[1] no, it wasn't BT for a few years

I've heard that story before  but more to the point, which one got the order? I ask because they are loads of AVO's around branded as GPO and BT but I don't recall ever seeing a DMM with either logo on them?

The person recounting the anecdote didn't reveal that.

But then the GPO wasn't always sensible. The background to why the top part of the slightly funky tower in this picture couldn't be fully occupied is both revealing and entertaining.



The tower had been opened in 1975 by QEII and was about to be occupied, when Health and Safety stepped in and said "oh no it isn't". Basically there was only one way up/down between the bottom bit and the rotated bit, and that would have been lethal in a fire.

So why was it allowed to be designed like that? When designed and built it was part of the Crown Estate, which was - and is - exempt from HSE laws. Then something changed and it (GPO? AdAstral Park? Martlesham Heath?) ceased to be part of the Crown Estate, and it thus became subject to HSE legislation. Oops; red faces all round.

Mentioning "Grenfell" will be considered tasteless.

[vk6zgo]

if you look at the HP service manuals, they don't tend to assume the meter impedance anywhere and the test points and voltage measurements are never at high impedance points without large warnings about it.

It's because they expect you to use a 3458A to check PSU voltages. (true story)

Edit: And before that, they assumed a 410b or sumtha'.

Dunno about the "b", but my 410C has a 100 M input impedance on most DC ranges.

I used a lot of AVOs over the years, but only ever saw one which had been smashed completely, as "throw the meter" wasn't a popular game back then!

I've seen a few DMMs which had gone to DMM heaven, although they still looked pristine on the outside.
The first UNI-Ts I used started to give weird resistance readings long before the battery alarm appeared.

Even my dear old Fluke 77 can get confused by a pulsed waveform when it was expecting smooth DC.

My Mum-in-Law's TV had a +150v rail supplied from a rectified overwind on the Horizontal Output transformer.
The filter cap had died, but the Fluke saw the resultant crud as a 108v DC voltage---a bit low, but not likely to cause the observed fault.
A 'scope told a different story, altogether!

[Specmaster]

I bet you're older than me, by quite some margin, but I love Avometers 

Yep, if you drop them, they're donald ducked, though the movements can survive, the casing will be shattered.

I don't love them, and have a couple of carcasses I will unload for a pittance.

Long ago I was working with GPO[1] Martlesham Heath and they told me of a "competition" between Avo 8 salesmen and  a DMM salesman. Everything was evenly matched until the DMM salesman picked up his offering, threw it across the room, and suggested repeating the competition.

[1] no, it wasn't BT for a few years

I've heard that story before  but more to the point, which one got the order? I ask because they are loads of AVO's around branded as GPO and BT but I don't recall ever seeing a DMM with either logo on them?

The person recounting the anecdote didn't reveal that.

But then the GPO wasn't always sensible. The background to why the top part of the slightly funky tower in this picture couldn't be fully occupied is both revealing and entertaining.



The tower had been opened in 1975 by QEII and was about to be occupied, when Health and Safety stepped in and said "oh no it isn't". Basically there was only one way up/down between the bottom bit and the rotated bit, and that would have been lethal in a fire.

So why was it allowed to be designed like that? When designed and built it was part of the Crown Estate, which was - and is - exempt from HSE laws. Then something changed and it (GPO? AdAstral Park? Martlesham Heath?) ceased to be part of the Crown Estate, and it thus became subject to HSE legislation. Oops; red faces all round.

Mentioning "Grenfell" will be considered tasteless.

About30 years ago I used to visit the engineers there a few times a year in my previous job, I used to get inside many interesting labs and factories.

[vk6zgo]

I'll take objection on this one. Fluke distributor visited the school where I was getting my first degree; that was part of the demonstration. Their professional sparky series of meters are designed to withstand a fall from the top of at least a 12-foot ladder.

Cheers,

mnem
 

Yep, good luck doing that with an AVO, but then only a blithering idiot would dream taking an AVO up a ladder.

Then what the fuck good are they?

mnem
a portable meter that doesn't port...?

I guess I must be a "blithering idiot", along with thousands of others, then .

Back in the day, there were no "steenkin' DMMs", so if a meter had to be used at height, you used whatever you had-----AVO, Simpson, University Graham, Metrix, or whatever, all of which were big & heavy.

Skill & care allowed people to do this---we weren't "cowboys", just had to work with what we had.
One big advantage to AVOs was the rugged leather handle on the top which allowed it to be tied off to any convenient point, like the top rung of the ladder.

Remember, those were the days when the "portability" of 7000 series Tektronix Oscilloscopes was lauded in their sales material.

The first type of portable DMM to receive approval by my then employer was the Beckman 310.
These rugged meters gave good service, the Fluke bench DMMs (too long ago to remember the model numbers), not so much.
One model of Fluke used to "play up" regularly, but was easily fixable, the next model was a total turd, ----the common saying was "it's a 'fluke' if it works!"

They never went for the early portable Flukes with the side buttons, which was probably a good idea--a later employer had one at the transmitter site with several buttons missing.

I bet it was the much more rugged later design which the Fluke guy chucked across the room!

[vk6zgo]

I bet you're older than me, by quite some margin, but I love Avometers 

Yep, if you drop them, they're donald ducked, though the movements can survive, the casing will be shattered.

I don't love them, and have a couple of carcasses I will unload for a pittance.

Long ago I was working with GPO[1] Martlesham Heath and they told me of a "competition" between Avo 8 salesmen and  a DMM salesman. Everything was evenly matched until the DMM salesman picked up his offering, threw it across the room, and suggested repeating the competition.

[1] no, it wasn't BT for a few years

I suppose there's always lots of ridiculous comparisons to make, that being one of them. No instrument is meant to be thrown. I guess that's where the DMM salesman lost his argument - it was all evenly matched, until he lost his temper.

Edited: for quote bracket thing was missing.

I'll take objection to on this one. Fluke distributor visited the school where I was getting my first degree; that was part of the demonstration. Their professional sparky series of meters are designed to withstand a fall from the top of at least a 12-foot ladder.

Cheers,

mnem
 

Yep, good luck doing that with an AVO, but then only a blithering idiot would dream taking an AVO up a ladder.

Yep, don't think that the full size AVOs were ever meant for anything other than bench/lab work of sorts. They made much smaller ones for out and about.

Nah! the little "Multi Minors" were pretty much a toy, something an EE might keep in his desk drawer.
The big AVOs went everywhere!

[25 CPS]

I’m aiming higher. This has been used in broadcast measuring van. And it came with manual with all the instructions one may ever need.
Hope it will re-activate and even elevate my DXing 
If not, I can still use it for 10MHz frequency reference GPS antenna, 4G router antenna, weather station, … 

Been there, done that. Be carefull they can kill. One nearly got me.

Thanks for the warning. Lightning? Collapsed? Accidental retracting?

I'd imagine that a genuine risk with those is driving off after failing to retract it. Add almost any overhead structure, but especially HV power lines to "fire for effect".

A crane on a barge plus overhead high tension lines works very well as Hydro One found out this afternoon.

[vk6zgo]

I'll take objection on this one. Fluke distributor visited the school where I was getting my first degree; that was part of the demonstration. Their professional sparky series of meters are designed to withstand a fall from the top of at least a 12-foot ladder.

Cheers,

mnem
 

Yep, good luck doing that with an AVO, but then only a blithering idiot would dream taking an AVO up a ladder.

Then what the fuck good are they?

mnem
a portable meter that doesn't port...?

AVO made smaller more portable meters, but the full size ones, such as the Model 8, I don't think was ever for general work up a ladder. I can't see why one would choose to.

Telephone Techs/Linesmen often had special, much smaller meters, (not AVO) with pretty poor specs.
The rest of us used the big beasts everywhere, as thats what we had!

[tautech]

I’m aiming higher. This has been used in broadcast measuring van. And it came with manual with all the instructions one may ever need.
Hope it will re-activate and even elevate my DXing 
If not, I can still use it for 10MHz frequency reference GPS antenna, 4G router antenna, weather station, … 

Been there, done that. Be carefull they can kill. One nearly got me.

Thanks for the warning. Lightning? Collapsed? Accidental retracting?

I'd imagine that a genuine risk with those is driving off after failing to retract it. Add almost any overhead structure, but especially HV power lines to "fire for effect".

A crane on a barge plus overhead high tension lines works very well as Hydro One found out this afternoon.

Pics please,  at the ready ! 

[25 CPS]

I’m aiming higher. This has been used in broadcast measuring van. And it came with manual with all the instructions one may ever need.
Hope it will re-activate and even elevate my DXing 
If not, I can still use it for 10MHz frequency reference GPS antenna, 4G router antenna, weather station, … 

Been there, done that. Be carefull they can kill. One nearly got me.

Thanks for the warning. Lightning? Collapsed? Accidental retracting?

I'd imagine that a genuine risk with those is driving off after failing to retract it. Add almost any overhead structure, but especially HV power lines to "fire for effect".

A crane on a barge plus overhead high tension lines works very well as Hydro One found out this afternoon.

Pics please,  at the ready ! 

Here you go:



https://www.cbc.ca/news/canada/toronto/power-outages-downtown-toronto-1.6548394

Unfortunately, the power remained on at work but off at the place I wanted to go to at lunch which has nice bacon sandwiches.  If only that situation had been reversed...

Edit:  The article contains a link to a video on Twitter which shows a nice arc flash right off the top.

[med6753]

More local CL finds.

https://newjersey.craigslist.org/ele/d/sparta-tektronix-mhz-oscilloscope/7510713135.html

That 2235 looks to be in good shape and reasonable price. About 1.5 hours away. Very tempting. BD.....does the 2235 have the trouble prone switcher PSU? Also, if I need a vintage transistor I know where to go. 

https://newyork.craigslist.org/que/ele/d/ridgewood-oscilloscope/7519309169.html

My first scope. Actually, was my Father's. When I left home to strike out on my own my younger brother got it. The seller is delusional with that $100 USD price. Not interested.

[med6753]

The B&K Precision 2120 looked lonely on the torture rack so I added a Type 422. No issues so far with burn-in.

[mnementh]

I'll take objection on this one. Fluke distributor visited the school where I was getting my first degree; that was part of the demonstration. Their professional sparky series of meters are designed to withstand a fall from the top of at least a 12-foot ladder.

EDIT: That's where their iconic yellow bumper holster came into being.

Cheers,

mnem
 

Yep, good luck doing that with an AVO, but then only a blithering idiot would dream taking an AVO up a ladder.

Then what the fuck good are they?

mnem
a portable meter that doesn't port...?

I guess I must be a "blithering idiot", along with thousands of others, then .

Back in the day, there were no "steenkin' DMMs", so if a meter had to be used at height, you used whatever you had-----AVO, Simpson, University Graham, Metrix, or whatever, all of which were big & heavy.

Skill & care allowed people to do this---we weren't "cowboys", just had to work with what we had.
One big advantage to AVOs was the rugged leather handle on the top which allowed it to be tied off to any convenient point, like the top rung of the ladder.

Remember, those were the days when the "portability" of 7000 series Tektronix Oscilloscopes was lauded in their sales material.

The first type of portable DMM to receive approval by my then employer was the Beckman 310.
These rugged meters gave good service, the Fluke bench DMMs (too long ago to remember the model numbers), not so much.
One model of Fluke used to "play up" regularly, but was easily fixable, the next model was a total turd, ----the common saying was "it's a 'fluke' if it works!"

They never went for the early portable Flukes with the side buttons, which was probably a good idea--a later employer had one at the transmitter site with several buttons missing.

I bet it was the much more rugged later design which the Fluke guy chucked across the room!

Yeah, Specmaster was a bit too quick on the draw to get the edit above included in his quote; of course those ruggedized meters were the ones they were flogging. 

mnem
of course, the 25/27 don'n need no steenkeeng bumper holster...

[mnementh]

*toddles off to sand a trestle*

ugggh. I got the smallest of 5 pieces of the trestle stripped with the sandcat tonight; no progress at all on finish-sanding any of it.

mnem
I am doomed. 

[mansaxel]

if you look at the HP service manuals, they don't tend to assume the meter impedance anywhere and the test points and voltage measurements are never at high impedance points without large warnings about it.

It's because they expect you to use a 3458A to check PSU voltages. (true story)

Edit: And before that, they assumed a 410b or sumtha'.

Technically "10M Zin" was the spec. They wanted to upsell you their instruments.

Of course. Never was there such a glorious instrument line-up as in the service manual. OTOH, this lead me to the path of what I think is my favourite hp instrument, the 428b. I saw it in the SM for the 410b and got curious. The rest is history.

[mansaxel]

They never went for the early portable Flukes with the side buttons, which was probably a good idea--a later employer had one at the transmitter site with several buttons missing.

I bet it was the much more rugged later design which the Fluke guy chucked across the room!

Dunno; I've got a bunch of those 8000 series portables, and they all hold up well. There's a re-cap in the near future of my 8060 ones, but only for longevity reasons, they still exceed specs and work as intended.  Most invasive repair I've had to do is replacing the 9V battery connector on one.

If I need to go up a ladder, I've got the Uni-T mA DC clamp/DMM in the tool case. Costs next to nothing, can go in a shirt pocket and is accurate enough for up-ladder work.  (HV work on ladders of course means one takes the USMC meter with suitable probulator. )

[bd139]

if you look at the HP service manuals, they don't tend to assume the meter impedance anywhere and the test points and voltage measurements are never at high impedance points without large warnings about it.

It's because they expect you to use a 3458A to check PSU voltages. (true story)

Edit: And before that, they assumed a 410b or sumtha'.

Dunno about the "b", but my 410C has a 100 M input impedance on most DC ranges.

I used a lot of AVOs over the years, but only ever saw one which had been smashed completely, as "throw the meter" wasn't a popular game back then!

I've seen a few DMMs which had gone to DMM heaven, although they still looked pristine on the outside.
The first UNI-Ts I used started to give weird resistance readings long before the battery alarm appeared.

Even my dear old Fluke 77 can get confused by a pulsed waveform when it was expecting smooth DC.

My Mum-in-Law's TV had a +150v rail supplied from a rectified overwind on the Horizontal Output transformer.
The filter cap had died, but the Fluke saw the resultant crud as a 108v DC voltage---a bit low, but not likely to cause the observed fault.
A 'scope told a different story, altogether!

In such situations you should practice “know thy circuit” first. Start with AC volts on your DMM then assume that is centred around the DC reading. That’s good enough to assert that the filter cap was not functional. Also the min/max reading on more complex DMMs is good for this.

I’ve had a couple of fucked DMMs but quite frankly the user would have been dead if it was an Avo.

[bd139]

More local CL finds.

https://newjersey.craigslist.org/ele/d/sparta-tektronix-mhz-oscilloscope/7510713135.html

That 2235 looks to be in good shape and reasonable price. About 1.5 hours away. Very tempting. BD.....does the 2235 have the trouble prone switcher PSU? Also, if I need a vintage transistor I know where to go. 

https://newyork.craigslist.org/que/ele/d/ridgewood-oscilloscope/7519309169.html

My first scope. Actually, was my Father's. When I left home to strike out on my own my younger brother got it. The seller is delusional with that $100 USD price. Not interested.

I wouldn’t touch another damn 2235 again. I was a nervous wreck after blowing MOSFETs on the preregulstor on that asshat.

https://www.eevblog.com/forum/testgear/tektronix-2235-repair-thread/

[tggzzz]

About30 years ago I used to visit the engineers there a few times a year in my previous job, I used to get inside many interesting labs and factories.

>40 years in my case Multimode fibre was making out into the field (and footway boxes). Monomode was still in the labs.

But yes. In my case some stories about how you retrieve a cable that's 3 miles away, or test one before you put it there.

[tggzzz]

Back in the day, there were no "steenkin' DMMs", so if a meter had to be used at height, you used whatever you had-----AVO, Simpson, University Graham, Metrix, or whatever, all of which were big & heavy.

Skill & care allowed people to do this---we weren't "cowboys", just had to work with what we had.

Precisely.

In my case at school it was a 1m piece of wire, a steel rule, a Weston cell, a NiFe cell, and a sensitive galvanometer for reading null.

I bet it was the much more rugged later design which the Fluke guy chucked across the room!

I was told the anecdote ~1980.

[bd139]

On Fluke ruggedness, I’ve seen a lot of totalled Fluke 25’s at hamfests. YMMV on assigning responsibility there 

[tggzzz]

I’m aiming higher. This has been used in broadcast measuring van. And it came with manual with all the instructions one may ever need.
Hope it will re-activate and even elevate my DXing 
If not, I can still use it for 10MHz frequency reference GPS antenna, 4G router antenna, weather station, … 

Been there, done that. Be carefull they can kill. One nearly got me.

Thanks for the warning. Lightning? Collapsed? Accidental retracting?

I'd imagine that a genuine risk with those is driving off after failing to retract it. Add almost any overhead structure, but especially HV power lines to "fire for effect".

A crane on a barge plus overhead high tension lines works very well as Hydro One found out this afternoon.

Oops.



And that isn't an oops on my part. I could be bothered to edit Dundas Sq out of the picture.

[dl6lr]

Re AVO weird battery requirement - on my to do list:

Mikeselectricalstuff coin battery mod

Ah, a nylock so they don't become loose by themselves...

[med6753]

More local CL finds.

https://newjersey.craigslist.org/ele/d/sparta-tektronix-mhz-oscilloscope/7510713135.html

That 2235 looks to be in good shape and reasonable price. About 1.5 hours away. Very tempting. BD.....does the 2235 have the trouble prone switcher PSU? Also, if I need a vintage transistor I know where to go. 

https://newyork.craigslist.org/que/ele/d/ridgewood-oscilloscope/7519309169.html

My first scope. Actually, was my Father's. When I left home to strike out on my own my younger brother got it. The seller is delusional with that $100 USD price. Not interested.

I wouldn’t touch another damn 2235 again. I was a nervous wreck after blowing MOSFETs on the preregulstor on that asshat.

https://www.eevblog.com/forum/testgear/tektronix-2235-repair-thread/

After reading your shit show with that 2235 it's definitely giving me 2nd thoughts. I'll mull it over during the weekend. Hopefully someone buys it by then or it just might be road trip and a glutton for punishment.