Test Equipment Anonymous (TEA) group therapy thread

[Cubdriver]

Speaking of power cables, anyone got one of those Tek power cables that looks like an extension cable they want to sell? (Number 2 in the attached image).
I have a type 284 pulse gen that needs one and I can't find a rewirable plug that will fit without removing the collar around the connection on the back of the unit.

I'm not sure how available they'd be in Japan, but I've had success doing surgery on NEMA 5-15 extension cords by taking the nub (that most now seem to have opposite the ground connection to prevent people from inserting grounded plugs backwards with the ground prong outside the receptacle) and hacking it off with a razor knife.

Pre-surgery on the left, post surgery on the right:




Looks like I must have taken thin slices at ~45° to the corners, too - too lazy to dig it out at the moment and look.

It's something of a tight squeeze, but it fits the receptacles on the scopes at least.


-Pat

[TERRA Operative]

I haven't seen them here specifically (90% of mains plugs here are non grounded) but I'll keep an eye out and see what I an find. Thanks!

[med6753]

Speaking of power cables, anyone got one of those Tek power cables that looks like an extension cable they want to sell? (Number 2 in the attached image).
I have a type 284 pulse gen that needs one and I can't find a rewirable plug that will fit without removing the collar around the connection on the back of the unit.

I'm not sure how available they'd be in Japan, but I've had success doing surgery on NEMA 5-15 extension cords by taking the nub (that most now seem to have opposite the ground connection to prevent people from inserting grounded plugs backwards with the ground prong outside the receptacle) and hacking it off with a razor knife.

Pre-surgery on the left, post surgery on the right:




Looks like I must have taken thin slices at ~45° to the corners, too - too lazy to dig it out at the moment and look.

It's something of a tight squeeze, but it fits the receptacles on the scopes at least.


-Pat

Yep, I've done the same thing.

[Robert763]

Yes, that works. You do have to trim the corners. We used to do it for IFR portable test sets used for aircraft maintenence. IFR charged a fortune for the "correct" lead which was poor quality nd failed were the cable entered the moulded plug. Unfortunatly you could not change them to IEC connectors because you can't break the calibation seals and back hen at least if you did it before sending for calibration it would come back with the original connector fitted and a bill for doing it 

[Specmaster]

Will someone please buy this, so that I don't have to?  https://www.ebay.co.uk/itm/255419336197

Nope 

[Zucca]

So I went out to get a table saw (Bosch 635-216) and a miter saw (well, who would have guessed, a Festool KS 60, pickup in about 10 days ...)

I carried my KS 120 from Germany, yes 220V here in USA :-).
Bosch 635-216 is not available here in USA, I will bend my knees to Dewalt or other less stellar brands. 

[Vince]

Tek 2467B

@Papy Smurf :

Thanks for the BOM ! Only 25 bucks for the whole lot from Mouser... I so wish Mouser (or Digikey) had operations in Europe so I could get the same prices !
Have to make do with Farnell with has less choice and is more expensive. The same BOM will probably cost me 50/100% as much 


@TerraOperative :

Thanks for the video ! Wow that was an excellent one ! 40 minutes of 2467B goodness, TSP levels of quality !
I learned an awful lot in that video for sure !

Wow you recreated the convoluted front panel flatflex, I am impressed ! 
I meant to ask you how it costs but I understand you have a partnership with PCBWay so you probably got it for and do'nt even know how much they would have charged ?
Anyway, looks like I will leave that flat flex well alone unless I really need to clean those pots  ! 
... but good to know that if I screw it up anyway, you have the Gerbers ready for me to get a new cable done !

So looks like I have an Mk1 scope then... the CPU board has the Lithium battery + RAM, not the later integrated NVRAM.
My scope is even older than yours.. battery dated December 1988 !  The ASICs on the main board are dated 6+ months prior to that, April/May 1988.
Thanks for the great detail about the battery replacement, I ought to do that before it's too late I guess ! 

Not touching the flat flex for now, however I still need to pull the front panel regardless, because one of the green status LEDs is kaput IIRC !
Too bad the main board needs to come out to pull the front panel 
Looks like most of the misery comes from having to desolder each and every BNC socket eh ? But looks like if approached calmly and one is taking his time, it should not be that difficult/risky of a job. I guess I shall see...
Problem is finding a new LED with the characteristics as the old one ! So that the colour and brightness are identical (enough) to "blend" with the others ! 
I guess back then there were no high brightness LEDs, so I need to get old school technology LEDs, to begin with. But then need one with the same wavelength and brightness / luminosity !
I will look in the part list, maybe there is a manufacturer part number in there, I could look up the datasheet to find specs and try to find something similar....
If not I guess I will have to buy many different makes and models and try them all to see which one gives the most acceptable result, gonna be time consuming ! 

I see a lot of electrolytic caps on the main boar as well ! 
Not touching this board unless proven faulty  AND until I have decent soldering gear. Need a powerful iron for this kind of large multi-layer boards, as well as a solder sucker iron gizmo like you have.  Not going to risk damaging the board with my old 50 Watt Magnastat Weller... 

Thanks again for the video !!! 


BLACK WIRE:

Oh wow yeah you were right, it's a pass-through for the fan ! 
Boy fro a distance it's everything but not obvious ! There is not much insulation between the inner and outer par, and the solder and wire strands wrapped around it hid 90% of the insulation, all you could see is a tiny bit of brown stuff (the insulation material..) that I simply mistook / assumed to be some flux residue ! 
But once desoldered yes, the pass through it perfectly visible and there is no mistaking any more ! 
The black plastic bracket right next to it is in the way big time, but it takes a couple seconds to remove / unscrew it, then you get much better access for the soldering iron...

Oh, and now I have the PSU freed, I looked more closely at the RIFA caps and sure enough one of them was responsible for all the smoke that escaped the scope('s butt ! 
Look at that cap ! 


OK so let's get cracking now !

[Saskia]

So I went out to get a table saw (Bosch 635-216) and a miter saw (well, who would have guessed, a Festool KS 60, pickup in about 10 days ...)

I carried my KS 120 from Germany, yes 220V here in USA :-).
Bosch 635-216 is not available here in USA, I will bend my knees to Dewalt or other less stellar brands. 

Actually the Dewalt 7485 or 7492 are apparently very good table saws. I would have preferred the 7485 to the Bosch, however the Dewalt is not readily available and it would have cost an additional 200€.
Which made it not worth it.

[Vince]

GLOWNIG Tek


Wow a couple ads popped up here on Leboncoin.fr , great example of the worse and best of humanity, respectively ! 

This guy is selling a crusty bottom of the barrel type 531A for freaking 200 Euros, even adding that his original price was 995 dollars, I guess to make it look like 200 Euros is almost a give away I guess ?!
Guy is on crack something good ! 

https://www.leboncoin.fr/equipements_industriels/2098795648.htm


Then at the other end of the spectrum, we have this gentleman near Paris who ACTUALLY gives away a beautiful type 502A in good nick, as part of house clearing it looks like... and you need to go pick it up tomorrow !

https://www.leboncoin.fr/equipements_industriels/2128368005.htm


Boy I wish I could go take it, but it's way too far, way too many driving hours. The trip would cost me 3 times what the scope is worth... I have to let it go sadly ! 
I will try to find consolation in the fact that I already have two of those ! 

[med6753]

The longer I let the Type 105 cook the lower the -150V creeps. I did perform an experiment. I have an isolation transformer where I can lower the line down to approx 110VAC and 105VAC. It made no difference. The reference is still out of spec so there is definitely an issue in the PSU that I will address.

Is that a zener or glow tube based reference? At least with zeners, a bit of drift after a really long off time might be normal.
One could speculate reasons for similar behaviour in glow tubes. (Does anyone know?)
A drifting resistor influencing the current through whichever reference device used is also a likely culprit.
I've had glass encapsulated "low tempco" zeners go bad and get become temp sensitive but otherwise working 
(Maybe "just" the zero-TC current changed in that case?)

The reference is VR tube based (5651). I have one in stock which I'll try swapping but I doubt it's bad. Most likely a resistor has drifted. I will post what I find.

You could check the voltage across the voltage reference tube, which should be around 86V, had one fail in my Tek 502.

David

You called it. Easy fix. The 5651 VR tube is FUBAR. The -150V now dead nuts.

Next is to calm down the bitching fan with an additional sleeve and then proceed with calibration.

[mnementh]

found storm damage on my garden shack ... nails holding down the tiles on the roof have been pulled out, the protective foils have lifted and curled up and the wood that makes up the roof has lifted and started to pull the nails out.   Eff.   Call to the insurance, they want photos and a quote ... now I need to find a craftsman that can actually repair this.   Also the door to the shack needs teardown and replacement.

Plus, I need to tackle the flooring on 1st floor. put in some vapor barrier plus some hardwood flooring. So I went out to get a table saw (Bosch 635-216) and a miter saw (well, who would have guessed, a Festool KS 60, pickup in about 10 days ...)   There's always work to do it seems.

This is all you NEED...

mnem
*agitating-ily*

C'mon - we in this thread all know that the correct hierarchy of acquisition of things is WANT > Need.  -Pat

Nope, not at all.  You really do NEED a bigger capacity battery for that tool!

LOL... I do have. Two 1.5s, six 2.0s, and a 4.0 for this and my circular saw, which was in storage with said saw when that pic was taken. Even with the $10 1.5AH pack, it still had no problem hacking through several ~200mm tree limbs that encroached on my shed when I moved it... the primary reason I did the Kobalt battery mod at that time.

I could also use my ritual sacrifice axe to split the floor boards, however Odin might frown on that.   Or detonating cord, however the collateral damage might be frowned upon.

What's wrong with using application specific high quality tools ?

Nothing... it's just not as much fun as agitatin'. 

mnem



I'll just do it... normally.

https://www.megacartoons.net/not-normal/

[mnementh]

So I went out to get a table saw (Bosch 635-216) and a miter saw (well, who would have guessed, a Festool KS 60, pickup in about 10 days ...)

I carried my KS 120 from Germany, yes 220V here in USA :-).
Bosch 635-216 is not available here in USA, I will bend my knees to Dewalt or other less stellar brands. 

Actually the Dewalt 7485 or 7492 are apparently very good table saws. I would have preferred the 7485 to the Bosch, however the Dewalt is not readily available and it would have cost an additional 200€.
Which made it not worth it.

mnem
"That's not sawdust... it's man-glitter." ~me

[dl6lr]

Thanks for the BOM ! Only 25 bucks for the whole lot from Mouser... I so wish Mouser (or Digikey) had operations in Europe so I could get the same prices !

With Digikey it is cheaper to buy just random stuff (or double/triple the order) to get free shipping. Any order below €50 and above €25 just does not make any sense. But this should never be a problem to me...

[mnementh]

...I've had success doing surgery on NEMA 5-15 extension cords by taking the nub (that most now seem to have opposite the ground connection to prevent people from inserting grounded plugs backwards with the ground prong outside the receptacle) and hacking it off with a razor knife.

   

-Pat

I've done similar, but found that the old benchtop belt sander makes getting the curve "just right" much easier... and it looks slightly less ghetto-fab than hacking with a razor knife. Of course, once plugged in it really makes little difference. 

mnem
 

[Vince]

Thanks for the BOM ! Only 25 bucks for the whole lot from Mouser... I so wish Mouser (or Digikey) had operations in Europe so I could get the same prices !

With Digikey it is cheaper to buy just random stuff (or double/triple the order) to get free shipping. Any order below €50 and above €25 just does not make any sense. But this should never be a problem to me...

I don't understand. Do you mean that Digikey now has operations in EUROPE ?! 

Since when ??

And nobody told me that ??

First and last time I ordered something from Digikey was 15 years ago, a " Dragon " programmer for Atmel MCUs.
Only decent affordable Atmel programmer back then. It was not sold in Europe, only the US.
When I saw that Digikey had a French website I though cool, I can get it in France then !!
Was overjoyed.... but not for long. When I got a message from the shipment company saying I had to pay $$$$ because it was imported from the USA, I was NOT happy anymore ! 
75 Euros programmer ended up costing me 150 !

So fuck Digikey and their " French" website ! 

But that was 10+ years ago. If they have operations in Europe now, well please do confirm and I will go celebrate that this evening with luxurious food, for a new world of plentyful & cheap componentry is now open to me ! 

[mansaxel]

Tek 2467B

@Papy Smurf :

Thanks for the BOM ! Only 25 bucks for the whole lot from Mouser... I so wish Mouser (or Digikey) had operations in Europe so I could get the same prices !
Have to make do with Farnell with has less choice and is more expensive. The same BOM will probably cost me 50/100% as much 

Mouser gives me free shipping and customs handling with Fedex as shipper, as soon as my shopping cart reaches 50€ ex VAT. And those packages almost all pass CDG, so I see no rational reason you should not be able to get the same deal.

If I'm not in a rush, I always use Mouser. They most of the time beat all European dealers, with exception for a few fringe items.

[vk6zgo]

Type 105: Successful power up. No smoke. But we do have some issues.

First issue. The critical -150V reference won't go any lower than about -160V. Line voltage related? Not sure yet. It's wired for 117V and my line voltage is typically 123V and higher. There's no wiring option for 125V. It could be something else and I'll check into it.

Looking good so far ! 

However I don't understand why you are complaining that the ref voltage won't go lower than -160V ?! It's not supposed to go lower than that, or even get as low as -160V to begin with, it's supposed to HIGHER Med, HIGHER , at -150V !! 
If it can go as far as -160V then why can't you adjust it -150V ?

Vince, this is an old argument, in that many people used to say negative voltages were, by definition, "lower" than positive ones, hence, greater numerical values of negative voltage were regarded as "lower" than lesser numerical values.

This point of view has largely died out, as it is confusing &, at least, to me, counterintuitive.
It is much easier to go by the numerical values of voltages of the same polarity-------thus, -160v is a higher voltage than -150v.

[mansaxel]

It is much easier to go by the numerical values of voltages of the same polarity-------thus, -160v is a higher voltage than -150v.

Alternatively, taking a cue from AvE, one can say, that at -160V the pixies are angrier than at -150V

[Zucca]

In other news: My geothermal pump had a guru meditation moment yesterday, and needed a controller reboot.

I hate those sporadic failures so much.... It is an indicator the board was not properly developed.
It should never ever happen.

I am black or white regarding this matter: either rock solid and always 100% working, or sporadic shit.
Am I the only one?

PS: That's why I sold ALL my raspy evil berry stuff on ebay. I am raspy free!

[med6753]

Then at the other end of the spectrum, we have this gentleman near Paris who ACTUALLY gives away a beautiful type 502A in good nick, as part of house clearing it looks like... and you need to go pick it up tomorrow !

A Type 502A is on my wish list but I would have to move. 

[Vince]

Type 105: Successful power up. No smoke. But we do have some issues.

First issue. The critical -150V reference won't go any lower than about -160V. Line voltage related? Not sure yet. It's wired for 117V and my line voltage is typically 123V and higher. There's no wiring option for 125V. It could be something else and I'll check into it.

Looking good so far ! 

However I don't understand why you are complaining that the ref voltage won't go lower than -160V ?! It's not supposed to go lower than that, or even get as low as -160V to begin with, it's supposed to HIGHER Med, HIGHER , at -150V !! 
If it can go as far as -160V then why can't you adjust it -150V ?

Vince, this is an old argument, in that many people used to say negative voltages were, by definition, "lower" than positive ones, hence, greater numerical values of negative voltage were regarded as "lower" than lesser numerical values.

This point of view has largely died out, as it is confusing &, at least, to me, counterintuitive.
It is much easier to go by the numerical values of voltages of the same polarity-------thus, -160v is a higher voltage than -150v.

Oh, didn't know that was a "subject " ! 

I guess to each their own, but over here at least, it's the other way around. -160 is factually a lower number than -150. Math being universal and undeniable, it's the most reliable way of eliminating confusing.

Saying that -160V is higher than -150 however IS very confusing to me !

But that's OK... the numbers don't lie, so as long as people don't write (+)160V when they reallymean -160V, we should be alright and circuits will still work! 

[tggzzz]

Type 105: Successful power up. No smoke. But we do have some issues.

First issue. The critical -150V reference won't go any lower than about -160V. Line voltage related? Not sure yet. It's wired for 117V and my line voltage is typically 123V and higher. There's no wiring option for 125V. It could be something else and I'll check into it.

Looking good so far ! 

However I don't understand why you are complaining that the ref voltage won't go lower than -160V ?! It's not supposed to go lower than that, or even get as low as -160V to begin with, it's supposed to HIGHER Med, HIGHER , at -150V !! 
If it can go as far as -160V then why can't you adjust it -150V ?

Vince, this is an old argument, in that many people used to say negative voltages were, by definition, "lower" than positive ones, hence, greater numerical values of negative voltage were regarded as "lower" than lesser numerical values.

This point of view has largely died out, as it is confusing &, at least, to me, counterintuitive.
It is much easier to go by the numerical values of voltages of the same polarity-------thus, -160v is a higher voltage than -150v.

In the UK there was a scratchcard(?) gambling game where the highest number won (no I don't know the details!).  It was stopped because too many punters were claiming that their "-6" was higher than "2".

Oh how we laughed at their ignorance.

[mansaxel]

Only 25 bucks for the whole lot from Mouser... I so wish Mouser (or Digikey) had operations in Europe so I could get the same prices !

I just checked out Digikey; who as soon as I said "Sweden" stated "Orders above SEK 430 ship free" and if I switch to French version says

Quels sont les Incoterms pour ma livraison ?

Devise Euro

Pour les commandes effectuées en euros, les Incoterms sont DDP (droits et douanes payés par Digi-Key).

And they also state:

LIVRAISON GRATUITE pour les commandes de plus de 50 EUR !

The future is already here, and for the most part is looking good. In this pretty narrow vector, that is...

[tggzzz]

Math being universal and undeniable, it's the most reliable way of eliminating confusing.

Ask people what is "1+2*3"? Include teachers

[mansaxel]

Math being universal and undeniable, it's the most reliable way of eliminating confusing.

Ask people what is "1+2*3"? Include teachers

They'll just google it, and Google recognises this, rewrites it as 1+(2*3) = 7, and case closed. (Because that's true; multiplication takes precedence, so the () are redundant but instructive.)