Test Equipment Anonymous (TEA) group therapy thread

[tggzzz]

Yes, my timer works !!!! To hell with the skeptics !!!!

Good job.

For ref, if you want to save some cash and actually not have to build the entire thing twice, firstly on a flakey ass breadboard, I can thoroughly recommend "dead bugging" the circuit on some FR4 single sided PCB.

Example I built (crystal frequency source):



When you're done you cut the board to size, drill a couple of holes to it and screw it to the bottom of the box and job done 

Looks cool BD but I have one problem with that 

What if you need to replace one of the DIP IC for whatever reason, like t's defective to begin with, or you blow it while working on the device ? That does not look like a lot of fun to replace those ICs.... whereas a socket saves your bacon 

I guess no solution is perfect, you gotta weight the pros and cons for each particular project / circumstances...

See several techniques (and some some "suboptimal" ones) at https://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/

Your last paragraph is spot on

[bd139]

Looks cool BD but I have one problem with that 

What if you need to replace one of the DIP IC for whatever reason, like t's defective to begin with, or you blow it while working on the device ? That does not look like a lot of fun to replace those ICs.... whereas a socket saves your bacon 

I guess no solution is perfect, you gotta weight the pros and cons for each particular project / circumstances...

I haven't blown a single IC yet doing it. I have however broken a pin off my last AD8307 though 

Edit: couple more examples. Works with SMD parts:



Discarded experiments:

[mansaxel]

Yeah agree there. No complaints here.

Edit: fuck it to previous comment that was here. Now own a 34401A. Display looks mostly ok. Circa 1999 HP brand so just pre Agilent. Should have an -02 display board in it. Down the rabbit hole I go...

Edit 2: Seller confirmed 10-05-02 rev so fine 

You have recovered well from the redheads-curries-walkabout-moving_house phase. I'm delighted and relieved at your return.

[Specmaster]

Yes, my timer works !!!! To hell with the skeptics !!!!

Good job.

For ref, if you want to save some cash and actually not have to build the entire thing twice, firstly on a flakey ass breadboard, I can thoroughly recommend "dead bugging" the circuit on some FR4 single sided PCB.

Example I built (crystal frequency source):



When you're done you cut the board to size, drill a couple of holes to it and screw it to the bottom of the box and job done 

I hope you kept good documentation for that, especially the schematic and BOM. Be a nightmare for anyone to work on it without those items to hand.

[tggzzz]

Now own a 34401A. ... Down the rabbit hole I go...

I know Luton is a hole, but the Dunstable Downs Radio Club hamfest is in a nice field, and the weather looks OK at the moment.

I started my nuttery there with an HP3468A. I may (or may not) decide to try to sell it there on Sunday, depending on how far I feel like walking

[tggzzz]

Yes, my timer works !!!! To hell with the skeptics !!!!

Good job.

For ref, if you want to save some cash and actually not have to build the entire thing twice, firstly on a flakey ass breadboard, I can thoroughly recommend "dead bugging" the circuit on some FR4 single sided PCB.

Example I built (crystal frequency source):



When you're done you cut the board to size, drill a couple of holes to it and screw it to the bottom of the box and job done 

I hope you kept good documentation for that, especially the schematic and BOM. Be a nightmare for anyone to work on it without those items to hand.

Much easier than a PCB, especially >2 layers.

[Cerebus]

Problem in this country is that too much of S Indian food is actually made by N Indian chefs - and they put too much chilli and sugar in it. Daughter even left a tripadvisor report to that effect at the last one we tried.

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

[Neper]

That takes me back to when I was a teenager and starting out with electronics.  One of my best friends had just gotten a scanner and we picked up cordless phones and analog cell phones with it.  To this day I remember one cell phone conversation we over heard from some guy asking how much further Yonge and Finch was in Toronto and said he was walking past some street near Yonge and Eglinton.  The reply was, "Keep walking, you're almost there..." which was completely wrong.  You're near Yonge and Eglinton and on foot wanting to get to Yonge and Finch?  You get on the subway and ride it to the end of the line - that's Yonge and Finch.  We cracked up laughing as this went on until the cell phone went out of range wondering how far the poor guy was going to end up walking.

Sometimes, you didn't even need a scanner.

In the late 1980s, some people over here had high-power cordless phones operating in the MF range around 1900 kHz, smack in the middle of the 160 m ham band. Totally illegal, of course.

One Sunday afternoon, listening around, I came upon what sounded like a doctor on some kind of hotline advising a succession of callers mostly about trouble they had with their medication. Deep male voice, very serious, quite the doctor. A few calls later, he apparently had a friend on the line and the same guy had one of the campest voices I've ever heard.

Quite clearly, he wasn't aware that he was broadcasting his phone calls for miles around. :-)

[25 CPS]

I’m having a slow day which is nice for a change.  So here is the teardown of the Stark capacitance substitution box:



It’s built up the same way inside as the resistance box I posted the teardown of some time ago with the large common wire loop and rotary switch selecting which resistor or capacitor is in circuit:



I’m not sure if the domino capacitor is original and the others are replacements or vice versa or if it’s all original still:



And here’s a closeup of the paper capacitors that we’re made domestically by Arrow Radio Ltd.:



I looked the company up and there’s an Arrow Radio Ltd. that was started in 2013 but obviously it isn’t the same company.  There’s almost next to nothing about the business that made these other than a couple brief listings in government directories and Statistics Canada reports on industrial levels that have been scanned in and put online.

I had thoughts of changing out the components in these two boxes with tight tolerance modern replacements to hot rod them but I’m going to leave them as is, particularly the capacitance box since it has that large selection of capacitors that were made here by that long gone company.  If I end up with another pair of these boxes that are intact, I’ll leave the nicer looking pair original and modify the others.

[mansaxel]

  So here is the teardown of the Stark capacitance substitution box:

How well does it match the values given?

[25 CPS]

  So here is the teardown of the Stark capacitance substitution box:

How well does it match the values given?

It's a bit all over the map.  Some values are spot on while others are closer to the next value up than the stated value.  I also haven't tested any for leakage either so I might spot check a few with the insulation tester this weekend just for fun.

[25 CPS]

Problem in this country is that too much of S Indian food is actually made by N Indian chefs - and they put too much chilli and sugar in it. Daughter even left a tripadvisor report to that effect at the last one we tried.

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

It's been a while.  Let me put it this way, London Underground was still deciding whether or not to continue generating their own electricity.  Are the wait staff at the Angus and Aberdeen steakhouses still all Polish girls that disappear the moment a police car drives by outside?

[tggzzz]

Problem in this country is that too much of S Indian food is actually made by N Indian chefs - and they put too much chilli and sugar in it. Daughter even left a tripadvisor report to that effect at the last one we tried.

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

I believe there are a number of "genuine" Keralan restaurants just west of Euston station. I haven't investigated them.

[Neper]

In my experience, the quality of Indian restaurants in the South East (we never get any further than that on our day trips from Dunkirk) has been on a steady decline for years. Either that or they've tried to rip us off, claiming our Mastercard wouldn't work and charging us scandalous rates for paying in euros. We're still mourning the loss of Taste of India in Dover.

[dl6lr]

Rifa madness excavation in the Tek 1240 PSU:

Replaced the two Y crapacitors that I removed with two KEMET MKP Y2 caps. No more leakage and the RCD stays calm 
The  replaced neon bulb now flashes when power is applied

Removed the Li-cell from the RAMPAK and found the one positive leg was broken (the other is not connected), so the measured voltage was remaining charge in the caps, not the cell. Cell has abt. 1.5V left and was replaced with a CR2032 holder and cell. Now voltage is 3.2V and the board and memory contents is persistent.

Similar cell on CPU board has still 2.8V and will be replaced later.

[Saskia]

just came back from some kayaking ...
(need to get in shape ...)
Received a tiny box from across the pond with some connectors and jumper wires in there, merci bien ...
Did not try out the stuff yet.
10 € customs.

Thanks a lot, Mike !

[mansaxel]

Problem in this country is that too much of S Indian food is actually made by N Indian chefs - and they put too much chilli and sugar in it. Daughter even left a tripadvisor report to that effect at the last one we tried.

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

I believe there are a number of "genuine" Keralan restaurants just west of Euston station. I haven't investigated them.

We have, what for Stockholm values of curry house, is a good one, near work. I believe the staff is mostly Pakistani. This is fairly common around here. There used to be a very good Pakistani restaurant in town (I once had a champignon soup there that managed to merge three taste sensations without them fighting; mushroom, brothy, creamy and umamish, chillies, strong, hot and straight, and coriander/cilantro, very flowery and complicating. It truly was something extra.), and there are a few others, also branded Pakistani, that come close, so not all are "indian" middle-of-the-road-cater-to-simple-expectations.

But I don't think we're advanced enough to cope with different India styles, though.

[Specmaster]

Yes, my timer works !!!! To hell with the skeptics !!!!

Good job.

For ref, if you want to save some cash and actually not have to build the entire thing twice, firstly on a flakey ass breadboard, I can thoroughly recommend "dead bugging" the circuit on some FR4 single sided PCB.

Example I built (crystal frequency source):



When you're done you cut the board to size, drill a couple of holes to it and screw it to the bottom of the box and job done 

I hope you kept good documentation for that, especially the schematic and BOM. Be a nightmare for anyone to work on it without those items to hand.

Much easier than a PCB, especially >2 layers.

Not with the dead cockroach (deadbug) style of mounting the IC's, noway of identifying them, unless of course it is the builder who is working on it and thus should know what they are, if they can remember   

[tautech]

  So here is the teardown of the Stark capacitance substitution box:

How well does it match the values given?

It's a bit all over the map.  Some values are spot on while others are closer to the next value up than the stated value.  I also haven't tested any for leakage either so I might spot check a few with the insulation tester this weekend just for fun.

Check switch contacts before anything else. Deoxit time. 

[bd139]

You have recovered well from the redheads-curries-walkabout-moving_house phase. I'm delighted and relieved at your return.

Oh I'm not recovered. I have enough time now to do all the things at once 

Not with the dead cockroach (deadbug) style of mounting the IC's, noway of identifying them, unless of course it is the builder who is working on it and thus should know what they are, if they can remember   

Well this is usually the problem of some poor unfortunate sod who buys a whole load of junk from an SK sale and spends weeks working out what it all is. It is definitely not the job of the dead guy. As someone who is nasty and insidious, I make sure that not only are the ICs upside down but there are absolutely no labels on the front or rear panels of anything I build just to make sure that whoever discovers it has to do some legwork. Tee hee.

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

Well I was served by a Ukrainian so YMMV with that assumption. The location was Crouch Hill for reference.

[tggzzz]

Yes, my timer works !!!! To hell with the skeptics !!!!

Good job.

For ref, if you want to save some cash and actually not have to build the entire thing twice, firstly on a flakey ass breadboard, I can thoroughly recommend "dead bugging" the circuit on some FR4 single sided PCB.

Example I built (crystal frequency source):



When you're done you cut the board to size, drill a couple of holes to it and screw it to the bottom of the box and job done 

I hope you kept good documentation for that, especially the schematic and BOM. Be a nightmare for anyone to work on it without those items to hand.

Much easier than a PCB, especially >2 layers.

Not with the dead cockroach (deadbug) style of mounting the IC's, noway of identifying them, unless of course it is the builder who is working on it and thus should know what they are, if they can remember   

"Doctor, doctor, my head hurts when I bang it against a wall."
"Well, don't bang it against a wall"

[Cerebus]

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

Well I was served by a Ukrainian so YMMV with that assumption. The location was Crouch Hill for reference.

Oh, it's not an assumption, it's based on what I was told by an accountant who specialises in the Indian restaurant business (or rather Indian owned Indian restaurants), and is a minority shareholder in a lot of them. It's not uncommon in that trade for the owners to want their accountant to have some 'skin in the game'. He's done quite well out of that, some of the people he's done that with have gone on to be very successful, a couple are even household names to people who watch 'foodie' TV. Weirdly his clients that aren't restauranteurs are professional photographers and it was through one of those I got to know him.

I've had some very good recommendations out of him over the years of places to try before they get good reviews, get popular and put their prices up, One of them was Cafe Spice Namaste which I visited when it's been open just a week or two. Nowadays it features in the Michelin guides.

[Vince]

Component sorting.  Have finally sorted that lot of big ass plastic packages.  As I thought 90% of it is tailored to CRT TV's....

x5 switch mode Vreg chips in "quasi resonant" mode says the datasheet, whatever.... it's too specific for me to ever use them so.. bye bye probably.

x16 NPN transistors, all tailored, say their respective datasheets, to drive the horizontal deflection of colour CRT TV's. Some even add "HIGH DEFINITION "colour TV's... I don't know.
So again very specific but... will keep them all because at the end of the day they are just high voltage beefy transistors and that can only be handy. Plus, big ones like that cost several Euros a pop, so I am glad I have 16 of them right there for free at my disposal... most are like 700 or 800V, and 8 to 20A... should be enough to blink an LED eh....

x1 lone N-MOSFET   900V 9A...
x1 Diode  600V 10A
x1 Triac  1,200V 25A... should be good enough to turn on the ceiling light in the living room, but barely...   
x1 Thryristor 800V 7A

x1 KA8301 That's a motor driver for small DC motors. Can control direction, can brake, and can vary speed as well using an analog input. Datasheet says it was intended for the load motor in VCR's... but a DC motor is a DC motor, so I will keep that chip. I like motor drivers...reminds of school when we entered a robot competition and I was in charge of making the driver for the two DC motors (IIRC they were front wiper motors from a Renault Clio of the day...), one for each driving wheel. Steering was achieved by making one wheel rotate at a different speed than the other. I still remember I was using a L298 chip, dual full H bridge driver in a SIL15 package, and it blew / exploded in my face as I had my nose literally 4 inches above the chip. I could have lost an eye.... got lucky... was 25 years ago now yet I still remember it like it happened this morning.... 

I was also in charge of driving the stepper motor that was agitating an IR emitter/receiver, scanning / searching for objects on the track... but that was low power stuff so nothing exploded on me... 
Was also me having to program our 80C552 development board to give the robot its smarts. That was even much lower power, nothing to be scared of there 

Anyway, this lot of components is quite interesting, glad to be adding that to my inventory. Now I can control tons of electrons at will so they blow stuff up ONLY when I decide that they should !

[bd139]

I can't speak for the rest of the country, but in London whatever it says on the front of the restaurant about the geographical style of the cuisine there's a 80-90% chance that it's actually being cooked by Bengalis, either from West Bengal proper, adjacent Indian states or from Bangladesh. If the restaurant is in Brick Lane that probability increases to 99%. Ironically, restaurants that explicitly centre around Bengali food are few and far between.

Well I was served by a Ukrainian so YMMV with that assumption. The location was Crouch Hill for reference.

Oh, it's not an assumption, it's based on what I was told by an accountant who specialises in the Indian restaurant business (or rather Indian owned Indian restaurants), and is a minority shareholder in a lot of them. It's not uncommon in that trade for the owners to want their accountant to have some 'skin in the game'. He's done quite well out of that, some of the people he's done that with have gone on to be very successful, a couple are even household names to people who watch 'foodie' TV. Weirdly his clients that aren't restauranteurs are professional photographers and it was through one of those I got to know him.

I've had some very good recommendations out of him over the years of places to try before they get good reviews, get popular and put their prices up, One of them was Cafe Spice Namaste which I visited when it's been open just a week or two. Nowadays it features in the Michelin guides.

Added to the restaurant queue. This is another new hobby of mine

[bd139]

In my experience, the quality of Indian restaurants in the South East (we never get any further than that on our day trips from Dunkirk) has been on a steady decline for years. Either that or they've tried to rip us off, claiming our Mastercard wouldn't work and charging us scandalous rates for paying in euros. We're still mourning the loss of Taste of India in Dover.

Indian restaurants, at least the ones I go in, tend to be cash only. Allows them to be somewhat creative with the accounting. If you turn up and use a MasterCard or pay in euros they're charging you what they are usually avoiding having to charge you