Test Equipment Anonymous (TEA) group therapy thread

[Andrew_Debbie]

-The incredibly stupid tire implementation

If you are worried about handling, the i3s is sooo much better than the standard i3.

BMW changed a lot of parts, even the steering rack.   The car is lower and wider than the standard i3.  Not by a lot but it made all the difference.

i3S is 175/55 R20 in the front and 195/50 R20 in the back.    That may seem narrow, but the contact patch is a decent size, especially compared to the  155 front 175 rear regular i3.

They are a bit  expensive, especially the rears.   

Buying wheels and spacers just to save £60 every 3 years?  Meh.

[Robert763]

I hate Texas Instruments DIP IC sockets.

I've hated them for 45 years....

[salvagedcircuitry]

-The incredibly stupid tire implementation

If you are worried about handling, the i3s is sooo much better than the standard i3.

BMW changed a lot of parts, even the steering rack.   The car is lower and wider than the standard i3.  Not by a lot but it made all the difference.

i3S is 175/55 R20 in the front and 195/50 R20 in the back.    That may seem narrow, but the contact patch is a decent size, especially compared to the  155 front 175 rear regular i3.

They are a bit  expensive, especially the rears.   

Buying wheels and spacers just to save £60 every 3 years?  Meh.

I was under the impression that bmw i3 owners were burning through tires every ~8 months. 3 years isn't so bad.
For me, NY roads are pothole city. A wider tire is absolutely essential.

[Ice-Tea]

Hope that helps,

mnem
 

It does! Thanks.

btw, Saskia, I checked for bits and bops bit I only have the PSU module for the N6700 mainframe. No accesories.

[Robert763]

HP 5315B with the nice amber LEDs on ebay
https://www.ebay.co.uk/itm/165383867235
No knowledge of seller

[mnementh]

Best all-round car Ive ever owned was a Audi S4 Avant, the B5 2.7 biturbo V6. Never failed. Could take it to any venue from a funeral / job interview to a car meet without issue. Could get a huge load of TE in the back. Only downside was fuel consumption and later on maintenance costs. I would not buy any 21st century Audi.

I'd def drive the wheels off a R8; prolly keep pushing my limits till I kill myself in it.

Buy one...? naaaah... not unless I somehow magically inherit the Stark fortune. 

mnem

[factory]

I hate Texas Instruments DIP IC sockets.

I've hated them for 45 years....

Could always flog them to Apple-phools. 

https://forums.overclockers.com.au/posts/15276674/

David

[Specmaster]

Yep, just results.  Bench testing before tying into the scope's +15V supply. The +15V through a 7812 regulator which drives the fan. Basic hand testing is demonstrating that the fan is pushing air quite well. Gonna let it run for a while to make sure the 7812 doesn't get too warm without a heatsink. I doubt it will.

Edit, the fan is also very quiet.

Ummm.... yeah... but I thought you wanted it to pull air out of the case? The way you have it here, it's pulling air into the case. You can tell just by looking at the curvature of the blades which way it's supposed to go, even if you didn't know that the supports/cable are almost always on the back of the fan.

mnem
notice I didn't say booty-fab even once.  oh fuck... 

When I took that picture and I looked at the install I went "you asshole, that fan is mounted backwards".  I decided to leave it and post anyway and see if anyone would notice. This picture is the CORRECT mounting.



Since you DID notice you get a cookie. 

There should be a little arrow moulded into the plastic on the side of the fan, which points in the direction of airflow, so to extract the arrow needs to be pointing towards the casing, and to pull air in, the arrow has to point in towards the scope.

[mnementh]

About half done.

mnem
*grilling*

[Specmaster]

I'm attempting to make up 1 x 6pin M-F Dupont lead and 4 x 5pin M-F leads and so far I've managed 1 5pin and half a 6 pin lead in about 90 minutes, what a faff. With that 10 way multicoloured ribbon cable you really need to tin the wires , trying to the strands into the crimp, in the crimper as per instructions is like pushing a piece of string. Taking a break to grab something to eat, I'm starving.

Maybe after I've eaten, the rest of the leads might be easier, I'll let you know 

[factory]

Tek 321A on ePay in the UK, set to max intensity as usual.  And no picture to show if the mains connector is present or bodged like my 321.
https://www.ebay.co.uk/itm/363770721401



Anyone looking for a HT PSU? Farnell E350 from CDL.
https://www.ebay.co.uk/itm/294880710960



And one of those scopes that nobody believes will trigger properly, in the US a HP 130C. 
https://www.ebay.com/itm/224901669333



I thought about trying to buy this parts mule in Europe, but then realised it's too new to provide a replacement transformer for mine, the display board is not original, would have had 7 segment devices.
https://www.ebay.de/itm/175208171907



David

[med6753]

Tek 321A on ePay in the UK, set to max intensity as usual.  And no picture to show if the mains connector is present or bodged like my 321.

I call bullshit.  He claims tested but he didn't test squat. It's showing classic symptom of tin whisker short of one of the 2N2207's in the sweep circuit.

Ask me how I know this? 

[mnementh]

I'm attempting to make up 1 x 6pin M-F Dupont lead and 4 x 5pin M-F leads and so far I've managed 1 5pin and half a 6 pin lead in about 90 minutes, what a faff. With that 10 way multicoloured ribbon cable you really need to tin the wires , trying to the strands into the crimp, in the crimper as per instructions is like pushing a piece of string. Taking a break to grab something to eat, I'm starving.

Maybe after I've eaten, the rest of the leads might be easier, I'll let you know 

Do yourself a favor and throw that ribbon in the trash; like mine, doubtlessly direct from Itscrapistan. Like 6 hair-thin strands; I doubt if it's legit even 28ga.

IIRC, I've done as big as 20 or 22ga with the Dupont connectors; I'm sure you have some form of stranded wire of the right gauge.

Scope out my step-by-step here one more time; if you have the same kit as mine, I promise you can get a decent enough crimp with them:

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3518566/#msg3518566

Cheers,

mnem

[TERRA Operative]

All this talk of the wrong cars, y'all just need a needlessly tricked out Toyota TRD Minivan! 

[med6753]

All this talk of the wrong cars, y'all just need a needlessly tricked out Toyota TRD Minivan! 

    

[BU508A]

Anyone looking for a HT PSU? Farnell E350 from CDL.

Tempted. Sadly, the seller doesn't ship to Germany.
Would be ideal for tinkering around with vacuum tubes.

[Neomys Sapiens]

Just wondering where you fellas would go if you needed a 30dB N-N attenuator (++GHz)? Ordered two from a UK shop a while ago but they never arrived...

EDIT: ... and gal. Sorry Saskia.

Basically, towards my cabinet or RF test aids case..
If it is for you and urgent - I could hand you one from Mini-Circuit for the Suhner price.
If you have one and I can take it off your hands - willing to pay Mini-circuits price for Suhner, Narda, Weinschel...
 

[Neomys Sapiens]

[..]

As the battery is old, I recharged it. Trying to do so with my power supply (bloody HAMEG, now Rohde&Schwarz, manual explicitly states battery charging is possible) the PSU went *POOF* Had to use the old style charger from the garage.
[..]
The PSU has blown the pass transistor and vaporized the shunt resistors. Have to order...

Oh, sorry to hear that! What's the exact type/model number, please - just so I can avoid these in the future?

Good luck for your repair.

THDplusN_notsobad

Sure. It is a HM 7042-2 Triple Power Supply. Despite the blown pass transistor, which could be due to a cheap TIP33C from ISCsemi, it has some design flaws (later for more). I got it cheap (€10,-) in defective state, it took me some time due to no available schematics. When I got it the second channel (0-32V, 2A) was displaying silly amps and no output. Problems I found in the device were:
- pre-owner removed the transformer windings from the channel
- pass transistor was blown
- shunt resistors vaporized

Then I got output and the ammeter showed proper results, but it produced nasty spikes on switching the output on/off. I finally found a SMD resistor that is across the DPDT-relay contacts was blown too, this lifts the regulation feedback from the output during switching (break-b4-make) so the regulation will drive the pass transistor like crazy trying to maintain the output voltage during switching.

During burn in tests I loaded it with 2A at 1V and the pass transistor was blown again. I replaced and noted to myself that this is not a foolproof lab power supply. Testing current step response with dynamic loading in CC mode showed some voltage spikes  on the output. Did not investigate further (confirmed by another owner of that PSU, at first I thought this was one more fault).

Design flaws that AFAIK still exists in later models (HM7042-5 is different and may behave well):

- channel 2 pass transistor is a TIP33C that will operate out of SOA on maximum load as the voltage after the caps is about 60V unloadad, 50V loaded, so the single TIP33C will (try to) dissipate up to 100W
- dodgy current regulation with very slow response, produces significant overvoltage spikes on step response
- manual states switch mode pre-regulation, but this is only implemented for the first channel (yes, that is quite a surprise that both channels are different)

I once had an appointment organized by Hays for a temp job there. I almost got in a shouting match with them about their crappy circuits and components. While I can see that a µC performs useful work in a modern lab power supply, the loop control is NOT among them. Period.
Luckily, they refrained from taking me in. 

[vk6zgo]

took some pictures earlier in the week at a stand of trees about 1/2 mile from the house.

the majestic bald eagle. 

subsist mostly on dead fish washed up on shore, roadkill, and garbage dumps.


"For my own part I wish the Bald Eagle had not been chosen as the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him."

Benjamin Franklin

Similar to the Australian Ibis.
Their relative, the "Sacred Ibis" was venerated by the ancient Egyptians, but the poor old Oz ones rejoice in the nickname "bin chicken" from their habit of raiding public rubbish bins.

Another trick is wandering all over house roofs, their size & ungainly feet making it sound like some scary large animal is up there.
That said, they are a beautiful bird, & even with their splaw feet & funny looking beaks, are a vital part of Australian wildlife.

[mansaxel]

I'm attempting to make up 1 x 6pin M-F Dupont lead and 4 x 5pin M-F leads and so far I've managed 1 5pin and half a 6 pin lead in about 90 minutes, what a faff. With that 10 way multicoloured ribbon cable you really need to tin the wires , trying to the strands into the crimp, in the crimper as per instructions is like pushing a piece of string. Taking a break to grab something to eat, I'm starving.

Maybe after I've eaten, the rest of the leads might be easier, I'll let you know 

Tinning leads before crimp is not good practice, so if you feel the need to do that, something's wrong. I'm with the dragon here, throw that craple in the metal recycle. I usually crimp stranded 0,22mm² with those crimpers. It is fiddly.  But not that much.

[TERRA Operative]

All this talk of the wrong cars, y'all just need a needlessly tricked out Toyota TRD Minivan! 

    

youtube.com/watch?v=IWWwM2wwMww

I wanted a sports car, the wife wanted a minivan so we compromised and got a minivan. 

I drive it 3 hours a day commuting into and out of Tokyo, so I gotta do it in style... Installed a set of vehicle specific Alpine X-Type 3-way speakers too for the commute. 

[TERRA Operative]

took some pictures earlier in the week at a stand of trees about 1/2 mile from the house.

the majestic bald eagle. 

subsist mostly on dead fish washed up on shore, roadkill, and garbage dumps.


"For my own part I wish the Bald Eagle had not been chosen as the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him."

Benjamin Franklin

Similar to the Australian Ibis.
Their relative, the "Sacred Ibis" was venerated by the ancient Egyptians, but the poor old Oz ones rejoice in the nickname "bin chicken" from their habit of raiding public rubbish bins.

Another trick is wandering all over house roofs, their size & ungainly feet making it sound like some scary large animal is up there.
That said, they are a beautiful bird, & even with their splaw feet & funny looking beaks, are a vital part of Australian wildlife.

[Ice-Tea]

Just wondering where you fellas would go if you needed a 30dB N-N attenuator (++GHz)? Ordered two from a UK shop a while ago but they never arrived...

EDIT: ... and gal. Sorry Saskia.

Basically, towards my cabinet or RF test aids case..
If it is for you and urgent - I could hand you one from Mini-Circuit for the Suhner price.
If you have one and I can take it off your hands - willing to pay Mini-circuits price for Suhner, Narda, Weinschel...
 

Heheh... I'm starting to figure out that ;

- might as well get them directly from mini-circuits. Less expensive than I thought
- including 2 weinschel pads in a previous deal for free was probably stupid.

[mnementh]

Just so you know... there's a reason Narda wasn't in my fleaBay list: At the time I was buying, I was warned by several folk in the long-range flight circles that there were oodles of fakes... or clones... or reclaimed factory rejects... on fleaBay at the time. This was over 10 years ago, so of course YMMV. But be aware that they were out there, and at least a few do certainly linger, waiting to pounce.

mnem

[PA0PBZ]

EBay (GSP) has just stolen my item

https://www.ebay.nl/itm/203864948409

Undeliverable - Item restricted at Global Shipping Center
The item in question has been deemed restricted. This could be due to import/shipping restrictions or eligibility requirements within the Global Shipping Program. The item will not be shipped to you nor returned to your seller.

It's not restricted, it is sold by Tilt 5 in the Netherlands. The seller got the money and I got my money back but I'd rather have the item, it was a good deal. I guess there's no sense in contacting them...