Test Equipment Anonymous (TEA) group therapy thread

[TERRA Operative]

I'll have to get a calibrated standard candle, do you think I can get a NIST traceable standard tea light?

[pcprogrammer]

I have to say it. A bit of an odd place for a connector, on top of the device. No way of stacking other devices on top of it like those humping ...... (Or is that to soon?)

[xrunner]

I'll have to get a calibrated standard candle, do you think I can get a NIST traceable standard tea light?

Maybe, just ask for the one that doesn't flicker. 

Just an experiment I would try if I had it, because I have too much free time on my hands. 

Get a real candle and see if it gives anywhere close to the "right" answer. 1 candle at 1 ft over 1 ft².

Maybe be modern candles are brighter than back in the day ... 

Where is the sensor?

[TERRA Operative]

I have to say it. A bit of an odd place for a connector, on top of the device. No way of stacking other devices on top of it like those humping ...... (Or is that to soon?)

It's designed so the sensor sits directly on top of the unit.
It's deceptively small, like small enough to palm it and lift it like Shaq O'neil palming a basketball, so I doubt it'd ever have much gear stacked on top.

I'll have to get a calibrated standard candle, do you think I can get a NIST traceable standard tea light?

Maybe, just ask for the one that doesn't flicker. 

Just an experiment I would try if I had it, because I have too much free time on my hands. 

Get a real candle and see if it gives anywhere close to the "right" answer. 1 candle at 1 ft over 1 ft².

Maybe be modern candles are brighter than back in the day ... 

Where is the sensor?

The sensor is long gone, as is usual for things that aren't permanently attached to old test gear.......

So, I'll make my own! I'll get a sensor element either locally or from Mouser-key and have a play around. I have a screen calibrator and a cheap light level meter that I can compare with to try to get at least in the ballpark with my readings.

[Vince]

@Vince - man are you really serious, wtf is happening here, I mean compared with the usual medical reports, "those stinky hobo hams" and the other stuff, your stuff was nice and refreshing in a beginners way, including the fridge timer and components sorting.

Please reconsider, don't let idiots win  !!!

Again I am sorry for my passage on TEA and all the suffering that caused to god knows how many people, I am scared now when I try to picture the extent of the damage I did to the TEA "brand".

Bon sang, Vince, don't be such a drama queen...

Have a good night's sleep and tomorrow your little world will be fine again. 

Thank you for your support and also people via PM. It appears that the angry people are a very small minority... so after two nights of sleep, I reconsidered my position and for the better or worse, I will stick around some more.... but I am still pissed at all that situation, I think I will take a step back a little and observe how things are going, before I commit heavily again... looks like this big mess will take a lot of time to heal 

At the end of the day there are lots of people here so it's statistically impossible to make everyone happy... it's up to each and everyone to figure out what is tolerable or not... and if everybody behaves like an adult and makes a little effort here and there for the common good, it will probably be fine for most of the people.... I hope.

I already have some content lined-up... it came out of the blue and landed on my bench from a friend who paid me an unexpected visit this evening.... 11PM here, tired, will start work on the thing tomorrow....it's something that has never been posted here I am sure, it's exclusive content for TEA !! 

Yes I like to tease...

[BU508A]

Some days ago I've received a Voltcraft MB-701 measurement adapter.



I've been asked to give some more details about it, so here they come.

Here are some detailed pictures of the probe. Thickness is 0.23mm measured. Not bad.


I've prepared a little experiment:
Some time ago I've built a little gadget to reform capacitors and measure the leakage current.
It consists of up to ten 12V batteries. One can connect up to ten capacitors at one time, the voltage
per capacitor can be chosen individually by pluggin the cable into the desired voltage step.
Voltage steps are of course 12V steps. On the third picture on can see the probe attached to one of the battery holders.




This is my 7510 measuring the current when the capacitor gets connected.

[Neomys Sapiens]

.
.
I've prepared a little experiment:
Some time ago I've built a little gadget to reform capacitors and measure the leakage current.
.
.

Is that a HERMETIC 700µF capacitor?
 
If so, whoa!

[Specmaster]

@Vince, its always a very small minority in anything that will spoil the pleasure for the majority and the authorities, regardless of who they, will always pander to them ever since the world so politically correct, its the squeaky wheel effect.

https://en.wikipedia.org/wiki/The_squeaky_wheel_gets_the_grease

[TERRA Operative]

Ignore the haters, post test equipment stuff, feed the addiction.

[pcprogrammer]

@Vince, here check it out a new fellow country member for you to welcome https://www.eevblog.com/forum/beginners/questions-from-a-beginner/msg4396444/#msg4396444

And maybe help him/her with the power supply question, or the other questions too of course

[McBryce]

Do you have a candle to check the calibration? 

According to the site I found this on, this should be suitable for TEA. 

McBryce.

[Robert763]

@Vince - man are you really serious, wtf is happening here, I mean compared with the usual medical reports, "those stinky hobo hams" and the other stuff, your stuff was nice and refreshing in a beginners way, including the fridge timer and components sorting.

Please reconsider, don't let idiots win  !!!

The $64,000 question is..., who might the idiots be then 

Idiot here, checking in!

Also, I'm a new RF hobbyist. For RF power meters (let's say 1 MHz - 500 MHz) it looks like my options are:

• Cheap used HP meter and a fairly expensive sensor head. Calibration is possible.
• Various ham power meters: MFJ, Bird, etc.
• Cheap ebay/AliExpress Golden Dragon PCB / OLED / SMA meters

Am I missing anything?

What power and frequency range?
There are other "professional" used power meters similar to the HP 43#X range. Marconi make a range including some (6460 etc) based on the General Microwave TfT sensors.

[Peter_O]

Do you have a candle to check the calibration? 

What about this hackable candle simulator:


Not cheap. Friend of mine has one.
At garden parties, in the evening kids up to 15 try to put a hand or finger into the flame. It's that well made. Live better than in this video.
(The PCB is not covered by any casing, so it is easily accessible for TE probes.)

[BU508A]

Do you have a candle to check the calibration? 

What about this hackable candle simulator:
https://youtu.be/LocrjlooIT4

Not cheap. Friend of mine has one.
At garden parties, in the evening kids up to 15 try to put a hand or finger into the flame. It's that well made. Live better than in this video.
(The PCB is not covered by any casing, so it is easily accessible for TE probes.)

They cost 510 Euro for one candle.
Can be bought here: https://shop.ingo-maurer.com/en/My-New-Flame-USB/3331131

[Vince]

@Vince, here check it out a new fellow country member for you to welcome https://www.eevblog.com/forum/beginners/questions-from-a-beginner/msg4396444/#msg4396444

And maybe help him/her with the power supply question, or the other questions too of course

Oh, another Frog ! 

Well I didn't have any expert knowledge on the very specific equipment he was asking about, but since he is a newbie I offered general advice instead, while still trying to be useful to him, I hope ! 

[Vince]

.
.
I've prepared a little experiment:
Some time ago I've built a little gadget to reform capacitors and measure the leakage current.
.
.

Is that a HERMETIC 700µF capacitor?
 
If so, whoa!

Nice bit of kit isn't it ? I have to say it looks kinda sexy.... 

[BU508A]

.
.
I've prepared a little experiment:
Some time ago I've built a little gadget to reform capacitors and measure the leakage current.
.
.

Is that a HERMETIC 700µF capacitor?
 
If so, whoa!

I've bought them as military grade wet tantalum capacitors.
Here is my little collection. The ERO ones are multipack tantalum capacitors, they just share the same storage box as the others.

1300µF 30V @ 85°C, 20V @ 175°C, manufactured by Mallory


700µF 60V @ 85°C, 50V @ 175°C, manufactured by Mallory


ERO Tantal, 680µF


I've measured the leakage current of the Mallory ones between 1nA and 450nA. Some of them do also "twinkle", I think, they need some more reforming time.

[pcprogrammer]

Do you have a candle to check the calibration? 

According to the site I found this on, this should be suitable for TEA. 

With that is should read zero candela, because it is not lit

What about this hackable candle simulator:
Not cheap. Friend of mine has one.

They cost 510 Euro for one candle.
Can be bought here: https://shop.ingo-maurer.com/en/My-New-Flame-USB/3331131

Ouch, not cheap is an understatement.

[xrunner]

Do you have a candle to check the calibration? 

According to the site I found this on, this should be suitable for TEA. 

McBryce.

 

I used to buy the electronic flickering TEA lights and tear them apart for the LED, which had a built-in "flicker" chip. Then I used that LED to simulate a camp fire or "bad" fluorescent light on my model RR. The neat thing was for $1 (now all dollar stores are $1.25) you got two or three lights and the CR2032 batteries, which anywhere else on their own would cost more than $1.25.

[capt bullshot]

They cost 510 Euro for one candle.
Can be bought here: https://shop.ingo-maurer.com/en/My-New-Flame-USB/3331131

Ouch, not cheap is an understatement.

At least the shop offers free shipping from 50 EUR 

[TERRA Operative]

TEA Time!
 
I FINALLY just got myself a TM5003 mainframe, Just won this auction now. Paid 7000yen (US$50.00) plus post for it.
I've been looking for one of these for a while now as the TM5006 is just a tiny bit big to put on the bench when I want to use just one or two TM5000 plugin modules... It'll come in handy for using my 3-bay sized SG5030 Levelled Sine Wave Generator when calibrating scopes.

With this, I have basically one each of every TM500/TM5000 mainframes (most I have multiples of...) except the TM515 portable one (but they are rather rare here in Japan, I've never seen one come up for sale ever).

Oh, and It's also got an AFG5101 12MHz Arbitrary Function Generator too. I might keep and use it, or might sell it on seeing as I have the AWG510 Arb Func Gen already anyway.
At the very least I'll give it a poke to get it up to snuff. Replace the backup battery, maybe install the Opt. 02 OCXO option too for some fun too (alliteration, yay!), and upload some nice photos to Tekwiki too.

[srb1954]

TEA Time!
 
I FINALLY just got myself a TM5003 mainframe, Just won this auction now. Paid 7000yen (US$50.00) plus post for it.
I've been looking for one of these for a while now as the TM5006 is just a tiny bit big to put on the bench when I want to use just one or two TM5000 plugin modules... It'll come in handy for using my 3-bay sized SG5030 Levelled Sine Wave Generator when calibrating scopes.

With this, I have basically one each of every TM500/TM5000 mainframes (most I have multiples of...) except the TM515 portable one (but they are rather rare here in Japan, I've never seen one come up for sale ever).

Oh, and It's also got an AFG5101 12MHz Arbitrary Function Generator too. I might keep and use it, or might sell it on seeing as I have the AWG510 Arb Func Gen already anyway.
At the very least I'll give it a poke to get it up to snuff. Replace the backup battery, maybe install the Opt. 02 OCXO option too for some fun too (alliteration, yay!), and upload some nice photos to Tekwiki too.

A great price!

[Vince]

So here it is !

As I said I bet it's never been posted here before ! 


So last evening afirend dropped this thing here... his wife's wax heater !!!  He cleaned it as best he could but it's still very horrible looking, tempted to wear gloves to work on this thing ! 
But it's just wax, it's not going to kill me...

Anyway, the announced symptoms / complaint are : " The temperature control is erractic, acting weirdly ".

So... I opened up the thing to check the pot, see if it was dirty, or the wiper not making a reliable contact... but it tested just fine ! It's wired a simple 2 wire variable resistor, not a pot. I measured the resistance with my DMM while rotating the shaft from end to end.... resistance varies smoothly from zero up to 20K or so. Never saw any hint of an intermittent wiper connection.... seems perfectly fine to me.

So then I realized the plastic bracket that hold the pot in place, is broken, in a million bits! It's beyond repair...
So maybe it's just that ! The pot not being held in place firmly, caused the weirdness ! I bet it's all there is to it...

However I can't be sure of that unless I test it... but how to test that the temperature regulation behaves properly with the input from the pot ?
I mean... the TIME CONSTANTS involved are wayyyy more than I have patience, or time really, for !

I need to find a way to have an instant feedback so that I can see how the temperature controller is reacting, in real time, as I turn the pot !

But that's not fun.... I mean, there is a circuit board in there, some electronics ! So of course I could not help but have a look at to see how it's put together...

First, the overall construction of the device :

There is the pot, a red light, power switch. Inside, there are bunch of white sleeved wires that go from the PCB to the "bowl" (whatever you call it...) where you put the wax to be melted.
all these wires look a bit intimidating, confusing... but looking closer it's not that mysterious anymore. I can clearly see two wires that must be the heating element. Then another two wires that go to something that's tightly coupled to the bottom of the bowl... so me assume it's a thermistor for the thermal regulation. Then another 2 wires going to another mysterious component, this time mounted on the metal bracket that hold the bowl inside the plastic enclosure. I thought maybe that one is a safety thermal cut-out switch, that cut the mains.

Then I looked at the PCB, and it seeed to confirm the above : what I thought might be the thermistor.. goes to the analogy part of the board, hence most likely involved in the thermal regulation. Then what I thought was a safety thermal switch... is indeed : it's wired in series with one of the mains wire that goes to the board.

Then the red light : it's wired to the analogy part of the board, not the mains side... so it's probably indicating when the heater element is being energized, rather than a dumb "the device is plugged in" indicator.

I guess this is bad news for my testing.... it means I can't turn the pot and see say, the TRIAC being driven more or less, to vary the average voltage across the heating element.... nope, it's probably just turning the heater on and off for long periods, and relying on the thermal mass to do the averaging.... so I am out of luck.. I will still have to wait for the thermal mass of the bowl to react, before I can decided if the heater is replying properly to pot inputs.... oh dear... what a waste of my time....

Anyway.

So what do have on the board ? This is an electronics forum I heard !

- Power supply : looks like we got a fuse soldered directly to the board, then probably what looks like a full bridge rectifier made form 4 discrete diodes, then followed by a film cap + zener regulation.

- Heating : looks like it's driven by a TRIAC, type BT137-600E, itself driven by a DIP8 opticoupler, a MOC3061. Looked it up, it's a photo triac with zero crossing circuitry in it.

- Regulation : I see a DIP8 LM358 op-amp, surrounded by 5 precision resistors.

- Visual inspection : can't see any suspicious solder joint, no components that have overheated or are cracked or whatever. However what I noticed, see below, is that there are a couple resistor lead up in the air, that are THIS close, 1 or 1.5mm away, from touching the metal tab of the TRIAC !!! 

That's it for now.... I can now power it up and measure things, give it a test drive, see what it does... so some TE will be involved ! Yes it IS on topic ! 

Hopefully I can fix this thing within an hour and clear the bench and resume my normal lab activities...

[TERRA Operative]

You know what you have to do......

Get some wax and give yourself a brazillian! It's the only way to properly test that it's working right. haha

[factory]

Vince, is that piece of junk using the X2 capacitor as a capacitive dropper? If it is, check it's not dropped in value and causing low voltage problems with the power supply. It's very hard to tell from the mess of wiring inside.
This type of circuit is very common these days, to avoid using expensive copper/iron lumps for the power supply.

Also check the electrolytic cap, could be dried out from being stuck underneath a heat source.

David