Test Equipment Anonymous (TEA) group therapy thread

[factory]

I've had a look at the display connector in my intermittant 54615B, of course it worked perfectly today  , was hoping to see something wrong on the Hsync signal, both HS/VS pulses measured fine. Will try again another day.   


The full/half brightness video signals, seem to be TTL level.


The intensity pot on the scope mainboard and probe comp output (based on divided Hsync signal).


The display connections on the mainboard of the 54615B.


David

[tggzzz]

Yonks ago, I remember driving a 100E Ford Popular back from London to Southampton on the M3.
Back in those days, the Poms were well into tailgating, with the worst offenders being "chaps driving Jaguars".
Downright terrifying, with the poor old "Pop" screaming its guts out, and a Jag bonnet emblem seemingly in the back seat.

Tailgating was not rare in Oz at the time, but I was surprised how 1970s Brits made an artform of it!
"Culture shock", I guess!

Since those days the tailgating in Britain has gotten worse, and it doesn't matter what make of car is behind doing the tailgating or in front being tailgated.  I'm as likely to be tailgated by Nissan Micra as I am by an Audi SUV. I'd say 1 in 5 cars that gets behind me holds back to a safe distance, so 4 in 5 are too close ranging from  half what it should be to "What have you got in your boot mate? I want a look.". It seems like the average driver no longer has any grasp of basic common sense physics ranging from optics (what they can see) through to dynamics (how soon they can stop), or physiology (what it will do to their bodies when they come to a sudden stop). There are days when I feel that I need a rear gunner with at least a 20mm cannon.

...ranging from optics (what they can see) through to...
should be  ...ranging from optics (what they can see through) through to...

Too many cretins tailgate vehicle that they can't see through into chichanes or when overtaking or when pulling out to pass parked cars. Then the vehicle in front pulls back in, and they are suddenly find they are in the path of an oncoming car. The look of shock/terror used to be entertaining, but it has become too repetitive for that.

[tggzzz]

Yonks ago, I remember driving a 100E Ford Popular back from London to Southampton on the M3.
Back in those days, the Poms were well into tailgating, with the worst offenders being "chaps driving Jaguars".
Downright terrifying, with the poor old "Pop" screaming its guts out, and a Jag bonnet emblem seemingly in the back seat.

Tailgating was not rare in Oz at the time, but I was surprised how 1970s Brits made an artform of it!
"Culture shock", I guess!

I've been known to repeatedly slow down and then speed up by 5mph.

I just let a gap build in front of me to two times the standard safe distance, decelerating gently if necessary, and try to give them an opportunity to "Go away!" as soon as possible. If that opportunity requires it, and road conditions permit it, I'll accelerate away and pull into a safe gap where they're not behind me. Being left in  a cloud of dust by someone who then drops back to their original speed, well out of their way, is usually enough hint that I want them to either pass me safely or keep the hell away. If they're really persistent I'll just indicate and pull over to the side of the road forcing them to pass me if they want to continue - I'd rather add a minute to my journey than have to spend the next x miles compensating for a tailgating idiot.

Yes, I'd rather have such cretins where I can see them - and avoid them.

I really ought to develop an index relating manufacturer vs how long it takes for the driver to Get A Clue. Wonder which would be beat/worst

Why not do it by gender, age, skin colour, wearing of a head covering (hat, wimple, turban, whatever), having children or some other entirely arbitrary characteristic? You'll get the same results whichever way, that associating a distinguishing characteristic with bad driving will just make you more likely to spot that characteristic when you spot bad driving. That's why people associate bad driving with "brand x". It's not that "brand x" drivers are any worse than drivers of any other brand, it's just that it's easy to reinforce your cognitive biases as you completely fail to attribute the "brand x" effect to any car of that make you see being driven well.

If the "brand x" attracts bad drivers effect was true, then it's converse would also be true: "brand y" attracts good drivers. However, I've never heard anyone hold forth that "Brand y drivers? They never cause any problems.". That's because people don't actively spot good driving the way they do bad, and therefore don't succumb to the human trait of trying to associate arbitrary labels with observed phenomena.

1) mensch ist mensch, the whole world over, so basing a bias on what people can't change is boring.
2) it is fun to find ways of pigeonholing people based on choices they deliberately made.
3) Accuracy? Who cares.

[Cubdriver]

Upper right…



-Pat

[Vince]

I prefer upper LEFT if you don't mind, for it's got Nixie tubes in it ! 

A " Signature Analyzer " wow that sounds fancy high tech and mysterious all at the same time.... do you hook up a camera to it and it reads a hand written signature and tells you if it's been forged or is legit ?
Pretty high-tech for the day indeed ! 


OK OK... I will go download the user manual to see what it does ... 

The HP noise generator at the bottom looks pretty nice, it deserves some cleaning for sure, please ! 

[Cerebus]

Now I think or it, one big advantage of punches is that you can make any shape you want, not just round holes... so it opens up an entire new world of possibilities 
You could make a hole with a flat, to fit pots and keep them from spinning round and round, or anything... as long as someone somewhere sells the shape that you want...

They used to be quite common - you could get punches for the classic potentiometer with flat, D connectors, IEC inlets, and so on. Last time I bought some sheet metal punches the ones for anything other than purely round and rectangular holes seemed to have disappeared off the lists of the moderately priced manufacturers and I didn't look at the extortionately priced ones.

[Vince]

Hmmm... that's definitely something I would be interested in finding.  Once the garage is built and I can start fabricating stuff to a decent standard, would definitely love to find all the punches you mentioned so I can make nice looking projects... Cutting and filing these shapes by hand is doable but so much more work and time to achieve a good result... punches to me would be worth investing a bit of money into. I guess cheap chinese stuff would be OK since I am not exactly into mass production..... from what you say, the Chinese have not invested this domain yet... well it will take 2 or 3 years at least to erect the garage, so it gives the chinese time to catch up ! 

[Vince]

Wow, think I found an interesting one here !

Just starting on sorting 60 or so DIL8 packages here.

I found an IL300-F ... an opto-coupler. OK no big deal but... that's no ordinary photo-coupler, look at the datasheet, that's one hell of a fancy one !

It's got a photo-PIN diode as its output device, and at the input there is a second photo-diode that samples the output of the LED, so you can use that as a feedback source to correct the driving of your LED, to make it super linear. Fast it is too. Expensive as well, still made today, 12 Euros a pop !!! 

Gee you learn something every day, there are some really weird and fancy opto-couplers out there...

[syau]

[img width=6°°]https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1528393;image[/img]

Boy, do I loooooveee hole punches, waayyy better than nasty holesaws. 

I don't understand... must have misread your previous post... though this amp was just a very vague long term project... and now you present us with a chassis... could you have been lying to us.... no, you would not do that.

Looks very clean/professional indeed... but what machine did you use that had enough force to punch through that metal, smoothly, i a controlled manner ? Surely a flick of a hammer won't do it... do you have a press ? That would be to just as interesting to see as the resulting holes... because I sure am interested as well.... links/costs etc....

Ha, I used a sheet metal punch, to cut the holes in a chassis I've had ready and waiting for a while.

Anybody know a good source of D shaped punch as it will be very handy to make holes for BNC and banana jacks.

[Vince]

Can't identify this one, if someone saw something like that before ?! 

G 3950 M or something. Google finds stuff but nothing relevant... cooling fans, SMD thermistors...

Have 5 of them... in case they are expensive and I can make money with them !

[srb1954]

Can't identify this one, if someone saw something like that before ?! 

G 3950 M or something. Google finds stuff but nothing relevant... cooling fans, SMD thermistors...

Have 5 of them... in case they are expensive and I can make money with them !

Possibly a SAW IF filter for TV sets.

Not much use for these since the demise of analog TV systems around the world.

[mnementh]

I'm thinking now that my original surmise is correct... provided nothing wrong with the mainboard, we should be able to get something useful on the screen with the 54621D and the CDM-7SF191 from my 54600A. Just need to see how they're modulating the brightness to get those greyscales. I guess my next step will be a breakout PCB. 

For now, tho, I've had to put it away; wifey has requested I look at the AC in our old Saturn.

mnem
 

Saturn AC is hopefully fixed. Dye shot last time I looked at it served its purpose; I found dye all over the front of the compressor. However, I did not find it all over the inside of the drive pulley or on the belt, which is usually so when the compressor blows a front seal. I did find a very suspect o-ring at the HI side port, however. That has been replaced, another dye shot, and system drawn down & recharged. If it doesn't hold a charge, most likely front seal on the compressor, so $$$.

It now blows freaking ice cubes, same as it always did. 

mnem
 

[Zoli]

Some time ago, I've purchased a Fluke 8060A(parts only, $42.00 - little expensive). Install new alkaline, turn on - no display. Open up, start checking - why the brand new battery has only 8.2V?
Well, the Gorilla was here, and left two shorts(Gorilla1-2.jpg; red arrow:short on the bottom, continued on the top thru a capacitor pin hole). Removing the shorts, the LCD came back to life; time to start the capacitor replacement.
Oops, more Gorilla footprints: broken LCD bracket(LCD_Support.jpg) and button support(Assembly_Support.jpg), Well, I need to dig out/install the Tools_of_Trade: Dremel, vertical tool stand, 0.5mm Carbide drill.
Glued the parts together with CA(Loctite.jpg) as placeholder, then proceed with the drilling. After drilling, add a drop of CA on the top of the hole, move the wires(0.45mm, leftover from the 10µF replacements) in-out a few times to fill the hole with CA, add a drop of accelerator on the top, then let cure for 24 h.
Replace the caps(surprisingly, no leaks) and the MAC socket, let the PCB and MAC soak in isopropanol for 24 h, short iso rinse, then dry for 24h more. Assembly, test - almost spot on. But since it has a good family to join, I've adjusted a bit...
Anyway, when I will have the time, I will make some tools to properly adjust/calibrate the whole family...

I just noticed that on one of your pictures the LCD mask is under the lower tabs / clips in the mount. This is incorrect and puts stress on the LCD. The mask should butt up to the tabs, not under them. Hopefully this was a before picture.

Unfortunately, this is the current situation. This was the only way to have all the segments working. If I move the mask out from the tabs, I'm losing some segments; assembly was done in nitrile gloves, so hand grease didn't contaminated the unit.
Remember: the LCD support was broken just under the tab, I had to fix it; most likely the Gorilla glued together quickly and with some offset. When I tried to clean the footsteps, the hidden damage already was done.
Thanks for the heads-up, I will keep my eye on the possible problems; if anything occurs, I will report back here with the solution.
Update:
I've opened up and checked the LCD assembly again. The situation is: not only the mask, but the polarizer is under the tabs, too. Reason: the left tab is loose, since the repair wasn't 100%.
Solution: 1. Leave it as is, since it's working.
               2. Change the whole LCD support.

[Vince]

Can't identify this one, if someone saw something like that before ?! 

G 3950 M or something. Google finds stuff but nothing relevant... cooling fans, SMD thermistors...

Have 5 of them... in case they are expensive and I can make money with them !

Possibly a SAW IF filter for TV sets.

Not much use for these since the demise of analog TV systems around the world.

Thanks !!! 

This is it !  I searched for " 3950 saw filter " and instantly got catalogues and datasheets showing that very same chip package and markings. They are band pass filters for TV IF as you said, thanks again !

So yeah, no use to me...

[mnementh]

I've had a look at the display connector in my intermittant 54615B, of course it worked perfectly today  , was hoping to see something wrong on the Hsync signal, both HS/VS pulses measured fine.
Will try again another day.      
The full/half brightness video signals, seem to be TTL level.   
The intensity pot on the scope mainboard and probe comp output (based on divided Hsync signal).   
The display connections on the mainboard of the 54615B.   

David

LALALALALALALALALALA!!! I can't hear you!!! I'm playing with my T3DSO2102!!!

No, seriously... Thanks. I'll get back on this sometime soon. I'm gettin' my freq on with the AWG function right now.

mnem
 

[mnementh]

Slight detour on the way up from the dwagon-cave; now that the Saturn is sorted, I went out to the garage and finally got the first coat of urethane down on the Anniversary Project table. We'll see if I prepped it right; it's been sitting a while. But hey; the stain is definitely dry. 

mnem
 

[AVGresponding]

I prefer upper LEFT if you don't mind, for it's got Nixie tubes in it ! 

A " Signature Analyzer " wow that sounds fancy high tech and mysterious all at the same time.... do you hook up a camera to it and it reads a hand written signature and tells you if it's been forged or is legit ?
Pretty high-tech for the day indeed ! 


OK OK... I will go download the user manual to see what it does ... 

The HP noise generator at the bottom looks pretty nice, it deserves some cleaning for sure, please ! 

Yes but the upper right unit matches the page number, rather the point...

[Messtechniker]

Wow, think I found an interesting one here !

Just starting on sorting 60 or so DIL8 packages here.

I found an IL300-F ... an opto-coupler. OK no big deal but... that's no ordinary photo-coupler, look at the datasheet, that's one hell of a fancy one !

Just search this forum for IL300 for quite a lot of information on this device. I use it all the time for isolating audio. See schematic with some real data.:

[BU508A]

Wow, think I found an interesting one here !

Just starting on sorting 60 or so DIL8 packages here.

I found an IL300-F ... an opto-coupler. OK no big deal but... that's no ordinary photo-coupler, look at the datasheet, that's one hell of a fancy one !

Just search this forum for IL300 for quite a lot of information on this device. I use it all the time for isolating audio. See schematic with some real data.:

The style of that schematic of this audio amplifier looks like a project from "elrad". Hmmmm....

[Messtechniker]

Wow, think I found an interesting one here !

Just starting on sorting 60 or so DIL8 packages here.

I found an IL300-F ... an opto-coupler. OK no big deal but... that's no ordinary photo-coupler, look at the datasheet, that's one hell of a fancy one !

Just search this forum for IL300 for quite a lot of information on this device. I use it all the time for isolating audio. See schematic with some real data.:

The style of that schematic of this audio amplifier looks like a project from "elrad". Hmmmm....

Maybe, but the circuit was further developed based on the data sheet examples and tested by me. Moreover I produced the schematic with Abacom SPLAN 7 resp. which today is SPLAN 8

[Robert763]

Now I think or it, one big advantage of punches is that you can make any shape you want, not just round holes... so it opens up an entire new world of possibilities 
You could make a hole with a flat, to fit pots and keep them from spinning round and round, or anything... as long as someone somewhere sells the shape that you want...

They used to be quite common - you could get punches for the classic potentiometer with flat, D connectors, IEC inlets, and so on. Last time I bought some sheet metal punches the ones for anything other than purely round and rectangular holes seemed to have disappeared off the lists of the moderately priced manufacturers and I didn't look at the extortionately priced ones.

Made obsolete in industry by laser cutting and CNC routing.
I've bought a 2mm laser cut panel with D shaped holes for less than a blank panel by the equipment case OEM

[Cubdriver]

The replacement lamps for the NLS voltmeter display arrived earlier in the week, and I got a chance tonight to get it back onto the bench to go through the display again.  I started by cleaning up the grounding springs using Deoxit, Scotchbrite and a small flat file, then after replacing the two known bad lamps put the display back into the meter with it in standby and manually stepped the relays through each position.  I pulled it out each time it landed on a non-lit digit and replaced each bad lamp in turn, verifying that they were then lighting.  In addition to the two I initially knew were bad, another four of them had to be replaced.

Grounding spring:


After cleaning:


The meter now appears to be working pretty well - it measures, but is off by a few tenths to the Fluke 8120A I was comparing it to.  Given that it uses a sixty year old zener reference in an ovenized can, lived in a basement for decades and hadn't been in operation in something like 30 years, I'd say it's in pretty good nick.


New video with all digits operational:


-Pat

[Atomillo]

Upper right…



-Pat

That HP noise generators seems quite interesting. I think it uses the same design technique of chaining shift registers that is explored in the Noise Sources part of the AoE.

If you do a teardown let us know!

[Specmaster]

Geez, I take a day out (Sunday) to attend an air show and when I get back I find you guys have generated 5 whole pages of input to wade through  . Air show was OK but could have been better, the best part of an hour just to gain entrance to the show ground caused by bad event planning  Flying started at 14:00, so we had 5 hours to kill before the display and all the time the sun was shining nicely. Just after the show started, it became very overcast with black storm clouds photography became a waste of time, then it started to rain, so we went and sat in the car and watched the Grand Prix on the car's inbuilt TV. The Grand prix was just 30 mile west of our location, and they had a beautiful but drama filled day. 

[Vince]

I prefer upper LEFT if you don't mind, for it's got Nixie tubes in it ! 

A " Signature Analyzer " wow that sounds fancy high tech and mysterious all at the same time.... do you hook up a camera to it and it reads a hand written signature and tells you if it's been forged or is legit ?
Pretty high-tech for the day indeed ! 


OK OK... I will go download the user manual to see what it does ... 

The HP noise generator at the bottom looks pretty nice, it deserves some cleaning for sure, please ! 

Yes but the upper right unit matches the page number, rather the point...

Oh ! So we are back into this game again ? I thought it was history ? 
When I joined TEA 15 months ago it was the 3000's and people were posted HP stuff every day, then came 4000 and a consensus was made that it was time to give upo on that game since very few people wanted to be flooded with CMOS chip pictures every single day.... so we it's now back again... hmmmm...... OK, I take note, I can play too....