Test Equipment Anonymous (TEA) group therapy thread

[mindcrime]

I don't know why I keep letting you lot talk me into this stuff, but I will soon be the proud owner of this new (to me)  Yokogawa WT210 Digital Power Meter.



And given that "a nice power meter" was on my list of "the last three pieces of test gear I could possibly ever need" that means I'm down to two things that I could possibly ever need. (Note: of course I could still want other stuff!)

Anybody want to take a stab at guessing what two items are still on the list? 

[McBryce]

So the Ordnungsamt can be seen as a type of Park warden who's duties extend beyond the park.

Their main function has become making money for the town. Parking tickets, fines of all kinds, the lot...

A while ago, there was a report in the local press about them setting up a speedcam on a stretch of motorway that's restricted to 100 kph. The town council were expecting.... well, what? 30 percent less accidents? No more casualties? Far from it. They were expecting 3 millions in fines per year.

Definitely. I got a speeding ticket for 136 on a 130kmh stretch of road just last month. The fine is for €10. The work, electricity and postage must have been more than that. Especially, as I like to transfer €10,05 to them so that they have to manually check and refund the 5 cents to me.

They're definitely not making big bucks from me

McBryce.

[Cubdriver]

I don't know why I keep letting you lot talk me into this stuff, but I will soon be the proud owner of new (to me)  Yokogawa WT210 Digital Power Meter.



And given that "a nice power meter" was on my list of "the last three pieces of test gear I could possibly ever need" that means I'm down to two things that I could possibly ever need. (Note: of course I could still want other stuff!)

Anybody want to take a stab at guessing what two items are still on the list?

LOL - sounds like you're soliciting suggestions for your current want list which we all know are items that in the future morph into needs.  I have no current input in that regard, but will happily watch for suggestions I may not have thought of.   

-Pat

[mnementh]

LOL... beat me to it, Pat. Almost word for word what I was thinking... 

mnem
*currently being abused by Frustion360*

[mindcrime]

LOL - sounds like you're soliciting suggestions for your current want list which we all know are items that in the future morph into needs.  I have no current input in that regard, but will happily watch for suggestions I may not have thought of.

LOL... beat me to it, Pat. Almost word for word what I was thinking... 

mnem
*currently being abused by Frustion360*

Blah, blah... you guys are so cynical. 

All joking aside, one of the two things on my list is more of a "want" than a 'need" in a sense, in that it doesn't represent a fundamentally new capability that I don't have already.

But no, the two last things I need/need'ish are:

1. An RF Power Meter, probably an HP E4418B

2. A nice high-end bench multi-meter, like an HP 3458A 8.5 digit jobbie

And that's it. 

Now, the "want" list... hmm... well... I have been lusting after a Tektronix TLA704 Logic Analyzer, but that's definitely just a "want" as I already own more logic analyzers than you can shake a stick at. 

[med6753]

My "want" list.




To finally power up. 

[tautech]

I am seeing something under that board but I don't know what it is. I should have time tomorrow to investigate this further. 

Behavior smells like a hinky cap to me.

I'm calling "bug", as in a dead desiccated spider lodged under the board between HV and chassis. 

I had exactly that in a PC PSU and it just sat there quietly simmering away where it crawled to its last until with a few days powered down in humid weather absorbed enough moisture to be properly conductive at the next power ON........BANG....cost me a PSU ! 
Little bugger ! 

[Specmaster]

My "want" list.




To finally power up. 

It will, you know it will because you'll beat it into submission.

[Cerebus]

I am seeing something under that board but I don't know what it is. I should have time tomorrow to investigate this further. 

Behavior smells like a hinky cap to me.

I'm calling "bug", as in a dead desiccated spider lodged under the board between HV and chassis. 

I had exactly that in a PC PSU and it just sat there quietly simmering away where it crawled to its last until with a few days powered down in humid weather absorbed enough moisture to be properly conductive at the next power ON........BANG....cost me a PSU ! 
Little bugger ! 

I did think about positing exactly that scenario for Med's bug. It kind-of fits the symptoms he's describing, bug goes "zap!" fault clears, leave it to cool, absorb a bit of atmospheric moisture and bend back into place, fault reappears.

[tautech]

I am seeing something under that board but I don't know what it is. I should have time tomorrow to investigate this further. 

Behavior smells like a hinky cap to me.

I'm calling "bug", as in a dead desiccated spider lodged under the board between HV and chassis. 

I had exactly that in a PC PSU and it just sat there quietly simmering away where it crawled to its last until with a few days powered down in humid weather absorbed enough moisture to be properly conductive at the next power ON........BANG....cost me a PSU ! 
Little bugger ! 

I did think about positing exactly that scenario for Med's bug. It kind-of fits the symptoms he's describing, bug goes "zap!" fault clears, leave it to cool, absorb a bit of atmospheric moisture and bend back into place, fault reappears.

If it wasn't from the hollow glass era I'd say a tant shorting and self healing...sputtering tants ! 

Might be worth scoping it with a DSO set in Single and a rising edge trigger....might be some clue in the waveform ? 

[mnementh]

My "want" list.




To finally power up. 

It will, you know it will because you'll beat it into submission.

Yup, it will... just long enough to make him look up, whereupon it will topple over and conk him on the head, Homer Simpson style. 

mnem
Law of Irony is a cruel taskmistress.

[mnementh]

I am seeing something under that board but I don't know what it is. I should have time tomorrow to investigate this further. 

Behavior smells like a hinky cap to me.

I'm calling "bug", as in a dead desiccated spider lodged under the board between HV and chassis. 

I had exactly that in a PC PSU and it just sat there quietly simmering away where it crawled to its last until with a few days powered down in humid weather absorbed enough moisture to be properly conductive at the next power ON........BANG....cost me a PSU ! 
Little bugger ! 

I did think about positing exactly that scenario for Med's bug. It kind-of fits the symptoms he's describing, bug goes "zap!" fault clears, leave it to cool, absorb a bit of atmospheric moisture and bend back into place, fault reappears.

If it wasn't from the hollow glass era I'd say a tant shorting and self healing...sputtering tants ! 

Might be worth scoping it with a DSO set in Single and a rising edge trigger....might be some clue in the waveform ? 

Ummm... commercially produced tants actually predate commercially produced oscilloscopes*... and if anybody would be using them in weird places, it would be Tek.  If it's new enough to have transistors, it certainly could have tants.

That said... given the location in a HV deflection circuit, I'd say much less likely that and more likely a polyester cap breaking down or rotten paper electrolyte matting failure in a conventional cap. I've even seen a cracked MMLCC behave this way at much lower voltages; wouldn't have believed it except I could actually seen the arcing between the layers once I got down to the board it was on.  Totes a moment, I tell you what.

mnem
 

*Yeah, okay... they were approximately coeval; early commercial scopes started to appear around 1930-1940, same time as the first commercially produced tants. But the scopes that came before tantalum caps appeared were still hardly more than a freerunning trace, not anything we would consider a modern scope with a precision sweep/timebase, and certainly no triggering, aside from a few bespoke experimental laboratory examples.

[med6753]

At long last it appears Mouser is back on track. Order submitted this morning and pick is already done for shipment tomorrow. 

[med6753]

In other news....in between other stuff today I've been turning on the 100V supply and in every case so far there has been no repeat of the overload nor any stray snaps, crackles, or pops. At least a half dozen times so far and nothing unusual. If it is a bug or spider trapped somewhere perhaps it's finally crispy critters and won't cause anymore issues. But I am going to pull the vertical board tomorrow and peek under it just in case. Once that's done I think it's time for the big event and full power with the external 100V supply.

I'll have the fire dept on standby. 

[mansaxel]

Tonight was Practical application of TE collection in attempt to FIX something time. As in the air/air heat pump that was put in before the geothermal and was left in place because it can do cooling too, at least before it broke. With temperatures around 26 old science degrees in the shade, cooling became a priority. Or so thought my wife. I'd already concluded "It's got a three-phase inverter motor driver and blows its main fuse, schematic is unobtainium, I'm calling thyristor fault. Some other day." which of course was not enough. And rightly so! 

Since the fuse blew only on compressor start ( that was my theory; there was a small delay before POOF) the problem would be in the external unit: that I was pretty certain of.  We crawled under the house, where the external lives, with dust and mosquitos. After some cleaning out and checking of caps with the DE-5000, I looked over a few power resistors on the PCB with my Fluke 10. All, caps and resistors, were comfortably inside their tolerances, nothing looked strange.  My prior attempts had been done solo, but with the wife at hand to push the power on while I was looking at the open unit from a suitable distance (comms set up via my Baofengs using one of the no-license channels), we fitted another fuse and turned things on, which led directly to a BANG and sparks coming out of the bottom of the unit. The defroster circuit has a bi-metal thermostat which opens on rising temperature, and it was from that area that the sparks and noise came.  It so turns out, that the position in the bottom of the unit where the thermostat sits is prone to contamination, and there simply was arcing to ground  from the defroster circuit, through a path of gunk, at the thermostat. 

I drilled out the pop rivets holding the thermostat, disconnected it, took it inside where we cleaned it thoroughly, megged it (Crank "Wee" Megger, of course) which it withstood well. Then I hooked it up with the 8060A in continuity mode, pressed an ice cube at its sensing belly and was rewarded with a "Click! BEEEEEEEP" which promptly stopped once I'd patted it dry and heated it in my palm.

Another round of cleaning, grabbed a rag and some brake cleaner in the garage, along with new pop rivets, cleaned the area around the thermostat and then reassembled things. Fitted a new fuse in the panel, turned things on and everything took off where it had been where the unit last had worked. That was in the winter though, so it immediately tried to heat the house... 

One house project done. So many more to go.

[mnementh]

Did you clean the drain in the pan under the defroster unit? And the drain hose to outside...? And the secondary drain, etc if so equipped?

mnem
*lessons learnt the hard way*

[Specmaster]

Started on the Casio WK3000 keyboard today that has a wonky power switch, it only works when it wants to and not when you want it to 

I was hoping to do some serious photos of this as I stripped it down to reveal the problem and its solution but sadly is not going to happen, the thing is too unwieldy to fit on the bench and work on it, let alone manipulate it for photographic purposes 

Given the prominence of Casio in the music world and the electronic world, I was expecting greatness from the insides of this beast, but greatness I never met. All the various boards and there are few of them in total, I expected would be connected together via looms on plugs and sockets, but no, ribbon cables that were all soldered directly to the boards 

The power switch was of the carbonised rubber membrane variety, along with the various option keys for the type of instruments to be played etc., a far cry from what I was expecting and also from my late fathers old Wurlitzer organ used. That thing was built like a tank, proper engineered and had decent switches for everything on it, unlike the Casio 

In order to safely gain access to the circuit boards, I had de solder 2 ribbon cables for the keys along with the power cables from the battery box, so I could then physically split the thing into 2 parts.

It transpired that some liquid had been spilt on some buttons around the power switch and had left contamination on the printed contacts, which I have now cleaned off and the switch now seems to be working correctly. I'll know for sure tomorrow when I get it all reassembled. When I acquired it, some tonal buttons where almost disappearing from view when depressed, which I hoped was the result of a gorilla being inside to try and fix the power switch, and then leaving some screws out. Sadly, not, although a gorilla had indeed been inside, all but 1 screw was infact in the correct place and tight. At some point in its life, it has received a shock and the plastic stand-off pillars in one corner had been ripped away from the main body. These have now been reglued back in position and left overnight to cure.

[mnementh]

I've run into this before with electronic instruments. Some people seem to think connectors in the signal path that can work loose or get crusty and lose integrity are the enemy, and this was a selling point for a while. 

Not sure if this was a period thing across the industry or if it was just a thing that made the rounds from one manufacturer to another; I just know what I heard from time to time in instrument stores, most recently when trying to sell my wife on a used piano.

mnem
 

[Cerebus]

Given the prominence of Casio in the music world and the electronic world, I was expecting greatness from the insides of this beast, but greatness I never met. All the various boards and there are few of them in total, I expected would be connected together via looms on plugs and sockets, but no, ribbon cables that were all soldered directly to the boards 

That's been the standard, usually along with punched single sided SRBP circuit boards,  in consumer grade electronic musical instruments for as long as I remember. Note too that's it's 'orrible solid core in that ribbon cable.

[beanflying]

Amazingly the contents of this poorly packed box arrived unscathed  Two minute peek inside as I have stuff to do not on the bench. Earthed of a fashion  Inverted mains plug is quirky and makes switching the GPO 'interesting'. And proving that even Companies in a production setting have a few loose screws laying around 

It makes volts close enough for 'stralia but I will load it up and look at the noise in a separate thread.

[med6753]

Amazingly the contents of this poorly packed box arrived unscathed  Two minute peek inside as I have stuff to do not on the bench. Earthed of a fashion  Inverted mains plug is quirky and makes switching the GPO 'interesting'. And proving that even Companies in a production setting have a few loose screws laying around 

It makes volts close enough for 'stralia but I will load it up and look at the noise in a separate thread.

Almost identical to mine on the inside. Only difference I see is in lower right. And exterior packaging is different. But I have no doubt they came from the same factory in China.

[mnementh]

Juicy! 

mnem
*knocks self unconscious with a shunt mallet*

[mansaxel]

Did you clean the drain in the pan under the defroster unit? And the drain hose to outside...? And the secondary drain, etc if so equipped?

mnem
*lessons learnt the hard way*

I've looked at a few of the "HVACR Videos" on the toobe. He seems to spend his days cleaning. Message gotten through. 

[mansaxel]

Given the prominence of Casio in the music world and the electronic world, I was expecting greatness from the insides of this beast, but greatness I never met. All the various boards and there are few of them in total, I expected would be connected together via looms on plugs and sockets, but no, ribbon cables that were all soldered directly to the boards 

That's been the standard, usually along with punched single sided SRBP circuit boards,  in consumer grade electronic musical instruments for as long as I remember. Note too that's it's 'orrible solid core in that ribbon cable.

Look into this:



which is a teardown of a significantly more expensive (~1700 €) and somewhat more modern instrument, a Nord Electro 3. Yes, there are stranded ribbon cables with connectors on them.

Factory tour:



The factory ("assembly" probably is  more correct) is in hip, gentrified area of central Stockholm.

[Robert763]

All the keyboard talk brings back memories of "contract" building a couple of Wersi organ kits as a teenager in the late seventies. They were really well designed bits of kit with quality PCBs and components. Lot of work though, one PCB per key for starters. Lots of soldering.