Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 14556034 times)

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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111650 on: January 19, 2022, 04:17:51 pm »
Matched 12AU6's installed in Type CA plug-in which is in turn installed in the Type 535A. 45 minute warm up. DC Balance: Perfect!  :-+



Is the rotation of the photo to compensate for the rotation of the trace..?    :popcorn:

Huh?  :-//

Might be parallax error but the trace does look like it's not horizontal. Looks like it's got a slight positive slope to it. Trace looks slightly below center on the left, and slightly above center toward the right end.
CRT rotation needs to be fine tuned, I say ! ;D

Nope, the trace is level.

I assume, they mean that the trace is a bit tilted.

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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111651 on: January 19, 2022, 04:20:58 pm »
Yes ! ;D
 

Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111652 on: January 19, 2022, 04:34:34 pm »



Such sexy. And I'm talking about the Reihenklemmen.    sed -i -e '/mind/d' /dev/gutter  :rant:

Having had infrequent but not non-existent exposure to high-current 400V circuit conductor termination I can see exactly where this will make sparkies very happy. It's such a mess trying to do this properly unless you've got the real stuff, and as soon as you get into screw terminations, a torque-controlled tool is more or less necessary, if you are to attain the same connection quality as spring-closed connections.

The problem with termination scenarios like this are not usually to do with the electrical side of it at all, but mechanical. Cable of that CSA is so stiff it's likely you're going to break the DIN rail clip on the back of the terminal while either a) getting the cable into it, or b) tightening the terminal to the specified torque, or c) 10 seconds after you walk away from it, it'll spontaneously ping off the rail...

Doing it in a lab like in the video is easy-peasy. Try doing it lying on your back in half-darkness and freezing cold inside a cramped sarel box, and see how easy it is.


My mate Tony's trick for this was to bend a dog-leg into the last foot or so of fat cables. Not only did it give you a springy bit to provide you with some wiggle room, if you got it just right it made the cable lie flat on the cabinet when you'd got it in place and you could even pin it to the cabinet with a P clip for extra tidiness and robustness. On some cables the conduit bender had to come out to do this trick, the Mk I knee not being sufficient for the job.
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111653 on: January 19, 2022, 04:45:41 pm »
Matched 12AU6's installed in Type CA plug-in which is in turn installed in the Type 535A. 45 minute warm up. DC Balance: Perfect!  :-+



Is the rotation of the photo to compensate for the rotation of the trace..?    :popcorn:

Huh?  :-//

Might be parallax error but the trace does look like it's not horizontal. Looks like it's got a slight positive slope to it. Trace looks slightly below center on the left, and slightly above center toward the right end.   CRT rotation needs to be fine tuned, I say ! ;D
   LOL... that much, just moving the scope a few feet could be the difference.

My 2465 disliked something about the right side of my bench at the old house... if I put it to my right hand (leftmost side of the bottom shelf) on the right shelving unit, the trace would skew ~3mm in a CW direction. Put it where it is in this pic, no problem. Change the shelving units L/R, still the same. Empty the entire gawddamn bench so the only thing on it were the 2465... still the same.  :wtf:

So I just got used to it being The Left Hand of Darkness;)

mnem
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« Last Edit: January 19, 2022, 04:54:07 pm by mnementh »
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111654 on: January 19, 2022, 05:19:09 pm »
Matched 12AU6's installed in Type CA plug-in which is in turn installed in the Type 535A. 45 minute warm up. DC Balance: Perfect!  :-+



Is the rotation of the photo to compensate for the rotation of the trace..?    :popcorn:

Huh?  :-//

Might be parallax error but the trace does look like it's not horizontal. Looks like it's got a slight positive slope to it. Trace looks slightly below center on the left, and slightly above center toward the right end.
CRT rotation needs to be fine tuned, I say ! ;D

Nope, the trace is level.

I assume, they mean that the trace is a bit tilted.



OK, maybe by a tenth of a mm or so. Who gives a rat's ass? No I.  :P :P :-DD
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111655 on: January 19, 2022, 05:29:28 pm »
Sorting through my boxes again... stumbled across this anonymous looking box, one of a few boxes full of old stuff that a long retired engineer friend gave me 3 years ago. Never had an opportunity to look in detail at all the stuff he gave me, life got in the way... now I do, as I am sorting through all my stuff bit by bit.

Box contains a big plastic container full of I am sure thousands of .. low power axial legged dipoles so to speak. Mostly 1/4W carbon resistors it looks. Some 1/8W. Some diodes, some caps as well, well I think they are caps, the light green bodied style. Or are they small inductors, can never remember...

Also in that box, a treasure... a brand "new" carton containing an assortment (9R up to 620k ) of 1% metal film resistors !  :D

Bodies look same size as your regular 1/4W carbon jobbies, but markings say they are rated at 0.6W, so more than double !  :o
Is that a typo or do metal film resistors handle heat so much better than carbon ?!

It says they are 50PPM , that's the tempco I guess. How good is that ? Good ? Average ? Bad ?

I can't see a brand name on it.. does someone recognize the "logo" / drawings on the box ?
It's old stuff so I doubt it's unbranded cheap Chinese stuff.. just was not a thing decades ago, compared to what it is today..

There is a part number on it though. It says :  MF60PHF  rings a bell ?

Anyway, would love to have some fun like Cerebus just did, but I don't have a fancy bench meter like he does !  >:(
Maybe one day when they get much cheaper...
Maybe if I get a cheaper / older one, that I could hook to GPIB and connect to a computer and with some S/W do something similar...

« Last Edit: January 19, 2022, 05:33:41 pm by Vince »
 
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111656 on: January 19, 2022, 05:39:20 pm »
Matched 12AU6's installed in Type CA plug-in which is in turn installed in the Type 535A. 45 minute warm up. DC Balance: Perfect!  :-+



Is the rotation of the photo to compensate for the rotation of the trace..?    :popcorn:

Huh?  :-//

Might be parallax error but the trace does look like it's not horizontal. Looks like it's got a slight positive slope to it. Trace looks slightly below center on the left, and slightly above center toward the right end.
CRT rotation needs to be fine tuned, I say ! ;D

Nope, the trace is level.

I assume, they mean that the trace is a bit tilted.



OK, maybe by a tenth of a mm or so. Who gives a rat's ass? No I.  :P :P :-DD

That's one big tenth of a mm then !  ;D
There is twice the trace thickness' worth of tilt  : left side, the trace is tangential to the center line, downward. And the right side it's tangential but upward.

Also, there is a one even bigger concern here : the horizontal amplifier clearly needs some attention ! For, the trace does not span the entire width of the graticule !

So need to calibrate the H amplifier gain and also check it for linearity at the same time.

Have fun and report !  8)

 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111657 on: January 19, 2022, 05:43:01 pm »

Also, there is a one even bigger concern here : the horizontal amplifier clearly needs some attention ! For, the trace does not span the entire width of the graticule !

So need to calibrate the H amplifier gain and also check it for linearity at the same time.

Have fun and report !  8)

Wrong Sherlock. The trace on a Type 535A does not span the entire width of the CRT in the X1 position. It is correct as shown. Don't believe me? Go look it up.
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Offline capt bullshot

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111658 on: January 19, 2022, 05:50:26 pm »

Box contains a big plastic container full of I am sure thousands of .. low power axial legged dipoles so to speak. Mostly 1/4W carbon resistors it looks. Some 1/8W. Some diodes, some caps as well, well I think they are caps, the light green bodied style. Or are they small inductors, can never remember...


We all have our boxes or bags of leftover unsorted components ...



BTW, the resistors in the blue box - I'm using them as disposable test points (solder one end to a test point on a PCB, and cut off the other leg). If the box ever gets empty, there's more resistors in the bag.

Quote

Also in that box, a treasure... a brand "new" carton containing an assortment (9R up to 620k ) of 1% metal film resistors !  :D

Bodies look same size as your regular 1/4W carbon jobbies, but markings say they are rated at 0.6W, so more than double !  :o
Is that a typo or do metal film resistors handle heat so much better than carbon ?!

It says they are 50PPM , that's the tempco I guess. How good is that ? Good ? Average ? Bad ?

Interesting kind of assortment this is.
Anyway 50ppm is the tempco, and pretty much standard for this kind of resistor, as 0.6W is standard for metal film resistors of this size.
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Offline Andrew_Debbie

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111659 on: January 19, 2022, 05:57:28 pm »
Three parcels arrived today.    The first was a Knitter toggle switch from RS, which goes into the PROM programmer. 

Distributer shortages? Order direct. 



Racal Dana 1998 arrived very well packed. 






« Last Edit: January 19, 2022, 06:17:34 pm by Andrew_Debbie »
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111660 on: January 19, 2022, 06:13:31 pm »



Such sexy. And I'm talking about the Reihenklemmen.    sed -i -e '/mind/d' /dev/gutter  :rant:

Having had infrequent but not non-existent exposure to high-current 400V circuit conductor termination I can see exactly where this will make sparkies very happy. It's such a mess trying to do this properly unless you've got the real stuff, and as soon as you get into screw terminations, a torque-controlled tool is more or less necessary, if you are to attain the same connection quality as spring-closed connections.

The problem with termination scenarios like this are not usually to do with the electrical side of it at all, but mechanical. Cable of that CSA is so stiff it's likely you're going to break the DIN rail clip on the back of the terminal while either a) getting the cable into it, or b) tightening the terminal to the specified torque, or c) 10 seconds after you walk away from it, it'll spontaneously ping off the rail...

Doing it in a lab like in the video is easy-peasy. Try doing it lying on your back in half-darkness and freezing cold inside a cramped sarel box, and see how easy it is.

Not to mention the huge forces that would come into play should there be a short circuit, that cable, big as it is, would become a wild anaconda thrashing about and ripping that termination of the din rail in flash.

Edit;

Just added this footage

« Last Edit: January 19, 2022, 06:19:59 pm by Specmaster »
Who let Murphy in?

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Offline Andrew_Debbie

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111661 on: January 19, 2022, 06:14:27 pm »
The Racal Dana 1998 looks like it may be working.  The buttons all work, for now.   It passes the internal checks and my quick tests.    As far as I can tell the motherboard is entirely original.     Should replace a few capacitors or leave it alone?

The rear panel lists options 04A  and 07.    The 07 battery option is completely gone.     I may build a modern one that drops in as a future design exercise.    04A  is the base +/- 3x10-9 OCXO.   But  look what I found. . .

 9462  == Isn't that option 04E, the ultra-high stability OCXO?   




 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111662 on: January 19, 2022, 06:27:37 pm »
Interesting kind of assortment this is.

Anyway 50ppm is the tempco, and pretty much standard for this kind of resistor, as 0.6W is standard for metal film resistors of this size.


Yeah, I first thought maybe a set to fill out to E-24, but no...  :wtf:

Only thing I can think of is an assortment made of cut reels off remainder lots, or perhaps this "assortment" was actually part of a BOM...

mnem
:-//

« Last Edit: January 19, 2022, 06:29:32 pm by mnementh »
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Offline m k

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111663 on: January 19, 2022, 06:32:22 pm »
Leather carry bag of Simpson DMM.
It has a rivet with a plastic addendum to keep the meter in place when the bag is closed.

The plastic addendum broke, it's from Illinois.
Advance-Aneng-Appa-AVO-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Triplett-YFE
(plus lesser brands from the work shop of the world)
 

Offline ch_scr

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111664 on: January 19, 2022, 06:52:06 pm »
Interesting kind of assortment this is.

Anyway 50ppm is the tempco, and pretty much standard for this kind of resistor, as 0.6W is standard for metal film resistors of this size.


Yeah, I first thought maybe a set to fill out to E-24, but no...  :wtf:

Only thing I can think of is an assortment made of cut reels off remainder lots, or perhaps this "assortment" was actually part of a BOM...

mnem
:-//
Hah, I got the same kind of resistors in a box! I think your friend had 1000pcs of each value and made mixed lots, because who needs 1000pcs of one kind?! I believe these are "Willow Technologies MF" Resistors. Maybe "OEM Brand"? IMHO 50ppm isn't too bad (for most cases even pretty good!), and these are well tested for stability, noise, mechanical strength etc. Very good e.g. to replace voltage divider networks in power supplies, where a less stable resistor could throw things off (introduce thermal drift or noise in the output voltage)
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111665 on: January 19, 2022, 07:16:28 pm »
The Racal Dana 1998 looks like it may be working.  The buttons all work, for now.   It passes the internal checks and my quick tests.    As far as I can tell the motherboard is entirely original.     Should replace a few capacitors or leave it alone?

The rear panel lists options 04A  and 07.    The 07 battery option is completely gone.     I may build a modern one that drops in as a future design exercise.    04A  is the base +/- 3x10-9 OCXO.   But  look what I found. . .

 9462  == Isn't that option 04E, the ultra-high stability OCXO?   
Other weirdos in here are looking at that hand-lettered serial number 045 and sighing...

mnem
 >:D
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Offline Andrew_Debbie

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111666 on: January 19, 2022, 07:22:11 pm »
Other weirdos in here are looking at that hand-lettered serial number 045 and sighing...

mnem
 >:D


I'm waiting for the owners of s/n 044 and 046 to raise their hands :)   

 
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111667 on: January 19, 2022, 07:35:04 pm »
ok, clobber me for unsafe jimmy-rigging ...

The plug has been removed from the socket. No one will touch this pin until I get the spare parts in.

1385141-0

blank wires of NTC and MOV stuck into a non fitting crimp-thingie to cut out the EMI filter
Crimp thingie stuffed directly into the cable shoes of the power switch. Isolation is for soft eggs (tm).

Obviously this is UNSAFE and has already been dismantled. Cable removed from outlet, etc.

But: the EMI filter obviously has a dead short. With this kind of rig the power board starts up, but the CPU still does not boot. For further debugging I would have had to touch components that I do not touch with this kind of improvisation. Spare parts are on their way, and when they arrive, the power box will be repaired properly before I continue to debug the pin.

Unfortunately I don't have any spare CPU boards here. I need to check the status LEDs to see if it boots, also inspect for battery leak damage. Once that is done and I can determine from the status LEDs that the board is booting I will have to direct my attention to the missing display.

BTW I do get a rather loud boot up ping. Which is good. It means that the audio board is working in principle. Could be that only the DMD board is dead. but: No further debugging until the power box issue is fixed and this thing is electrically safe again.
Then it'll be measuring the voltages, checking all are there, and then checking boot up and DMD operation. Once that is done: check solenoids, flashers, lamps, switches. Then clean playfield, swap out rubbers and bulbs for LEDs, repair any plastics.

1385147-1
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111668 on: January 19, 2022, 07:40:00 pm »
Leather carry bag of Simpson DMM.
It has a rivet with a plastic addendum to keep the meter in place when the bag is closed.

The plastic addendum broke, it's from Illinois.
Of course, the snaps/rivets are available as a kit from anywhere for cheap; search term is "boat cover snaps" or "snap kit".

https://www.amazon.com/s?k=snap+kit&crid=12BVCE4Q7A51O&sprefix=snap+kit%2Caps%2C71&ref=nb_sb_noss

The plastic "addendum" looks like a job for 3DP, or perhaps some strategically stacked screw/washers/nylok nut.

mnem
*toddles off to pick up SWMBO*
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111669 on: January 19, 2022, 07:42:47 pm »
ok, clobber me for unsafe jimmy-rigging ...

.....snip


I don't think anyone dare yell at you because you are well versed in explosives. If they did they be a dumb ass.  :P :-DD
« Last Edit: January 20, 2022, 01:43:38 am by med6753 »
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Offline McBryce

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111670 on: January 19, 2022, 07:49:24 pm »
The Racal Dana 1998 looks like it may be working.  The buttons all work, for now.   It passes the internal checks and my quick tests.    As far as I can tell the motherboard is entirely original.     Should replace a few capacitors or leave it alone?

The rear panel lists options 04A  and 07.    The 07 battery option is completely gone.     I may build a modern one that drops in as a future design exercise.    04A  is the base +/- 3x10-9 OCXO.   But  look what I found. . .

 9462  == Isn't that option 04E, the ultra-high stability OCXO?   
Other weirdos in here are looking at that hand-lettered serial number 045 and sighing...

mnem
 >:D

They're just amateurs who can be kept happy with double digit serials. Anything above 009 is mass production! :D

McBryce.
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Offline m k

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111671 on: January 19, 2022, 08:08:31 pm »
Leather carry bag of Simpson DMM.
It has a rivet with a plastic addendum to keep the meter in place when the bag is closed.

The plastic addendum broke, it's from Illinois.
Of course, the snaps/rivets are available as a kit from anywhere for cheap; search term is "boat cover snaps" or "snap kit".

https://www.amazon.com/s?k=snap+kit&crid=12BVCE4Q7A51O&sprefix=snap+kit%2Caps%2C71&ref=nb_sb_noss

The plastic "addendum" looks like a job for 3DP, or perhaps some strategically stacked screw/washers/nylok nut.

mnem
*toddles off to pick up SWMBO*

Yes, I just didn't expect the maker being molded there.

Easy fix was a rubber door stopper, not pretty but the meter has LCD in pieces also so, no rush since <2mm screws are behind the mailman.
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111672 on: January 19, 2022, 08:39:48 pm »
Other weirdos in here are looking at that hand-lettered serial number 045 and sighing...

mnem
 >:D
I'm waiting for the owners of s/n 044 and 046 to raise their hands :)



       BWAHAHAHAHA!!!

They're just amateurs who can be kept happy with double digit serials. Anything above 009 is mass production! :D

McBryce.
I know you're not joking, so why am I still laughing...?  :-DD

mnem
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111673 on: January 19, 2022, 08:45:33 pm »

Also, there is a one even bigger concern here : the horizontal amplifier clearly needs some attention ! For, the trace does not span the entire width of the graticule !

So need to calibrate the H amplifier gain and also check it for linearity at the same time.

Have fun and report !  8)

Wrong Sherlock. The trace on a Type 535A does not span the entire width of the CRT in the X1 position. It is correct as shown. Don't believe me? Go look it up.

That does not seem very practical, why would Tek torture their users so much, why.... so yes I obeyed and went to look it up !  ;D

Don't have a 535A so I just downloaded the manual from Tekwiki.

I went all over it, and everywhere it showed, said, or implied, that it should span the entire graticule !  ;D

See below the page pertaining to the calibration of the time base. I highlighted two things :

1) Top right, it says clearly one should adjust the sweep to get 10.5cm span ! As any other glowing scope.

2) Bottom left : that might be where the confusion lies. They say that when checking / adjusting the sweep for linearity, you should ignore the first and last cm/DIV of the trace because that's where most of the non-linearity always is. That's all. They never said to reduce the span of the trace, only to ignore the first/last bits for calibration purposes...  :-//

Do I get a cookie ?

With lots of chocolate chips please !  :P

« Last Edit: January 19, 2022, 08:56:22 pm by Vince »
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #111674 on: January 19, 2022, 08:58:54 pm »
ok, clobber me for unsafe jimmy-rigging ...   The plug has been removed from the socket. No one will touch this pin until I get the spare parts in...

PFFFFT!   Empirical engineering at its finest. Nobody in here is going to say boo to you for what you do while you're triaging a patient; what's important is to get things to light up.



Mission fucking ACCOMPLISHED!  :clap:

In this pursuit, you choose how safe or how dangerously you want to play it. As long as it's safe when it goes out the door or into service, what goes on in the interim is nobody's effing bidness. Of course, we all really want you to do the really dumb shit on video so we can point and laugh when you get yourself lit up like Tim Taylor... ;)

mnem
alt-codes work here:  alt-0128 = €  alt-156 = £  alt-0216 = Ø  alt-225 = ß  alt-230 = µ  alt-234 = Ω  alt-236 = ∞  alt-248 = °
 


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