Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1610326 times)

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Offline Cubdriver

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2975 on: October 19, 2017, 07:50:51 pm »
My big concern is that she likes to gnaw and lick things, and sometimes bites at the AC mains cords plugged into the power strips mounted to the underside of the shelf.  She hasn't bitten through one, but it could get ugly if she does.  She gets yelled at and rather unceremoniously dropped to the floor when she starts doing that!  (This, as might be expected, does little or nothing to deter her.)

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Offline URI

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2976 on: October 19, 2017, 07:52:19 pm »
The discussion regarding desoldering stations has led me to buying a ZD-915/ZD-985 clone:
Solder Peak SP-1010DR: https://www.tme.eu/de/details/sp-1010dr/entloetstationen/solder-peak/

Thanks to dave: His review of a ZD-985 made my decision easy.  :-+


That will make the job of harvesting cherry keys from surplus PC-105-keybords a lot easier (6 waiting).
I already harvested one keyboard using a manual vacuum pump.  :palm:
My left hand ached so much after that I haven't continued ever since.
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Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2977 on: October 19, 2017, 08:40:20 pm »
Yes I agree, I watched Daves vid and then went on Ebay and purchased this one, I must say its an extremely handy tool, makes light work of removing parts for testing, replacement or just harvesting, hand pumps and desoldering braid, forget it, get one of these, job done.
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Offline Berni

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2978 on: October 19, 2017, 08:54:24 pm »
Yeah cats can have quite a bit of biting power. One of my cats has chewed a cord on a phone charger right in half, including the copper and everything like one would have taken a pair of side cutters to it. Luckily that cat didn't do it very often.

Maybe there is something that can be rubbed on to cables to make them taste awful. I heard of a case where they had problems with birds pecking away at the ribs on a rubber HV isolator rod and eventually tearing them off, the solution was to mix in one of those incredibly bitter tasting compounds in to the rubber and that did make them stop for good.
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2979 on: October 19, 2017, 09:01:02 pm »
After some research and a few emails around, someone I used to work with years ago has an old Weller desoldering station in his loft that was skip dived so he's going to dig that out for me. It's a Weller 801 apparently  :-+

I hate cats. Fluff, hair, spit, get in everything, destructive, smelly, poop everywhere, bring in dead things, lick their arses, fussy, expensive vet bills, scratchy. Trade off in cute factor isn't worth it.
 

Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2980 on: October 19, 2017, 09:16:44 pm »
After some research and a few emails around, someone I used to work with years ago has an old Weller desoldering station in his loft that was skip dived so he's going to dig that out for me. It's a Weller 801 apparently  :-+

I hate cats. Fluff, hair, spit, get in everything, destructive, smelly, poop everywhere, bring in dead things, lick their arses, fussy, expensive vet bills, scratchy. Trade off in cute factor isn't worth it.
Thats a result on the weller, I'm sure you'll love it apart from its a bit of big beast to sit on your bench, needs a lot real estate.  :)

What have cats done to you? my cats are not like that at all, they are very clean and loving animals.
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Online Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2981 on: October 19, 2017, 09:31:43 pm »
Thats a result on the weller, I'm sure you'll love it apart from its a bit of big beast to sit on your bench, needs a lot real estate.  :)

What have cats done to you? my cats are not like that at all, they are very clean and loving animals.
My experience is that cats tend to be less of a nuisance to their owners than they are to their environment. They dislike pooping in their own or owners yard, so it tends to happen nearby. Not that I don't fancy cats, but I can't say my neighbour's cats don't cause some problems. Relieving themselves on the propery or even repeatedly in the house would be one of them. Note we don't own a cat, they just walk in. Very regular extended fights at night would be another. Admittedly, the high cat density doesn't really help.

That said, I do enjoy petting one or two that seem to fancy me. As long as I don't pet their bellies, we tend to be friends ;D
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2982 on: October 19, 2017, 10:01:44 pm »
I am on the receiving end of a lot of pooping. Several of the local cats use our garden as a toilet. My neighbour has sorted his cat out because every time I catch his cat shit in my garden it ends up on his conservatory roof. He got the point and bought a tray.

If you don't have a litter tray, your cat is probably shitting in someone else's garden.
 

Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2983 on: October 19, 2017, 10:26:28 pm »
I can honestly say that my cats do not leave the garden, we have 6ft wooden fence all round which was put up to keep neighbours dogs out who used to come into our garden and use it as a loo, a playground because theirs was a mud patch and also to chase and worry our cats. Prior to the fence being installed their dogs got one of my cats and bit its tail which cost us almost £1,000 in vets bills having its tail amputated to save its life as a result of those dogs in our garden.

My cats were terrified of going out in the garden because of the dogs, so they have become more of a house cat but now because of the fence, they do enjoy going out and enjoying the garden but they stay in the garden as long someone is with them. when we come in, the cats will follow, just like dogs in that respect, so I do know for 100% certainty that my cats do not cause any problems to neighbours and neither do they poop in the house or in the garden without burying it in a patch we keep dug for them to use as a toilet. We keep them in at night as responsible owners, we take care of our pets unlike many others who love them when they are at the cute kitten stage and then leave outside to fend for themselves 24/7 almost for the rest of their lives.  :popcorn:
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2984 on: October 19, 2017, 10:38:08 pm »
What have cats done to you? my cats are not like that at all, they are very clean and loving animals.

Er, no.

People worry about infections from dogs, so now dog owners carry their shit around in their pockets. But for some reason they ignore toxoplasmosis gondii from cats. The lifecycle is https://www.cdc.gov/parasites/toxoplasmosis/biology.html

Solid estimates are that 60m (~20%) of people in the USA are infected (95% in some places). It is symptomless except when it isn't - but why worry, heart/brain/eye damage only occurs much later, so the cause can't be isolated and the owner prosecuted. https://www.cdc.gov/parasites/toxoplasmosis/gen_info/faqs.html

The effect of t. gondii in the other host, rats, is "entertaining": it suppresses cats' fear so that they become more likely to eaten by cats, thus completing the lifecycle. There is inconclusive suggestive evidence that t. gondii has mind-altering affects in humans, viz schizophrenia, bipolar disorder, cognitive defect. However, t. gondii  does stop humans smelling cat urine, so maybe it is only a matter of time before a causal link is shown. https://en.wikipedia.org/wiki/Toxoplasma_gondii
« Last Edit: October 19, 2017, 10:42:58 pm by tggzzz »
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2985 on: October 19, 2017, 10:55:09 pm »
 

Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2986 on: October 19, 2017, 11:11:03 pm »
Because it starts counting at zero, duh. ;)


mnem
There are 10 kinds of people in the world; those who don't understand binary and those who get their heads bashed in for making stupid binary jokes.

Try again. This isn't fencepost errors, it's an instrument that operates in the time domain; it's a counter/timer.

I shall resist linking the obvious picture of Bob Widlar.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Online Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2987 on: October 19, 2017, 11:31:59 pm »
I can honestly say that my cats do not leave the garden, we have 6ft wooden fence all round which was put up to keep neighbours dogs out who used to come into our garden and use it as a loo, a playground because theirs was a mud patch and also to chase and worry our cats. Prior to the fence being installed their dogs got one of my cats and bit its tail which cost us almost £1,000 in vets bills having its tail amputated to save its life as a result of those dogs in our garden.

My cats were terrified of going out in the garden because of the dogs, so they have become more of a house cat but now because of the fence, they do enjoy going out and enjoying the garden but they stay in the garden as long someone is with them. when we come in, the cats will follow, just like dogs in that respect, so I do know for 100% certainty that my cats do not cause any problems to neighbours and neither do they poop in the house or in the garden without burying it in a patch we keep dug for them to use as a toilet. We keep them in at night as responsible owners, we take care of our pets unlike many others who love them when they are at the cute kitten stage and then leave outside to fend for themselves 24/7 almost for the rest of their lives.  :popcorn:
While I'm not saying it's the same in your case, I've heard cat owners claim the exact same thing. The story fell apart just a tiny bit when the furball had to be removed from the living room of the neighbouw for the third time :P That it must be other cats is fairly typical cat owner banter.

Again, I'm not saying this is true in your case.
 

Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2988 on: October 19, 2017, 11:47:50 pm »
I can honestly say that my cats do not leave the garden, we have 6ft wooden fence all round which was put up to keep neighbours dogs out who used to come into our garden and use it as a loo, a playground because theirs was a mud patch and also to chase and worry our cats. Prior to the fence being installed their dogs got one of my cats and bit its tail which cost us almost £1,000 in vets bills having its tail amputated to save its life as a result of those dogs in our garden.

My cats were terrified of going out in the garden because of the dogs, so they have become more of a house cat but now because of the fence, they do enjoy going out and enjoying the garden but they stay in the garden as long someone is with them. when we come in, the cats will follow, just like dogs in that respect, so I do know for 100% certainty that my cats do not cause any problems to neighbours and neither do they poop in the house or in the garden without burying it in a patch we keep dug for them to use as a toilet. We keep them in at night as responsible owners, we take care of our pets unlike many others who love them when they are at the cute kitten stage and then leave outside to fend for themselves 24/7 almost for the rest of their lives.  :popcorn:
While I'm not saying it's the same in your case, I've heard cat owners claim the exact same thing. The story fell apart just a tiny bit when the furball had to be removed from the living room of the neighbouw for the third time :P That it must be other cats is fairly typical cat owner banter.

Again, I'm not saying this is true in your case.
Haha, well that is not true for our house, these 2 cats don't kill anything unless you count moths and daddy long legs, even spiders make them jump. I caught them in the kitchen the other day with a spider, admittedly its a pretty big spider but the cats stood between it the back door and the spider stood its ground and they having a Mexican standoff. Suddenly the spider decided to make a run for the open door and freedom and ran towards the cats and they lept up and over the spider, who escaped into the garden. My cats are such big killers that couldn't manage to see a spider off even  :-DD
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2989 on: October 19, 2017, 11:58:45 pm »
The one cat I did have was bloody useless. It caught mice, licked them for a bit and let them go. I had to go round with a metal ruler and finish them off.  :horse: (replace the horse with a mouse). One day it just buggered off and moved in with the neighbour because she fed it ham.
 

Online Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2990 on: October 20, 2017, 12:11:09 am »
Haha, well that is not true for our house, these 2 cats don't kill anything unless you count moths and daddy long legs, even spiders make them jump. I caught them in the kitchen the other day with a spider, admittedly its a pretty big spider but the cats stood between it the back door and the spider stood its ground and they having a Mexican standoff. Suddenly the spider decided to make a run for the open door and freedom and ran towards the cats and they lept up and over the spider, who escaped into the garden. My cats are such big killers that couldn't manage to see a spider off even  :-DD
The furball in this story was the cat itself. Despite the owner feverously denying the cat ever went outside of the house or yard, having it brought back a handful of times by a neighbour who found the creature in his own house ruined to story just a tad.
 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2991 on: October 20, 2017, 12:27:37 am »
The furball in this story was the cat itself. Despite the owner feverously denying the cat ever went outside of the house or yard, having it brought back a handful of times by a neighbour who found the creature in his own house ruined to story just a tad.
Thats like my neighbour who breeds cats and dogs but denies it despite when they moved in they showed me the dogs and cats with puppies and kittens and offered to sell one or more to me. Anyway, as mentioned earlier, their dogs were always in our garden and barking / howling in the times when they were shut away in their garage (done out like pet shop with puppy and kitten pens etc, that they flatly denied that their dogs were ever in our garden or that they kept barking at all hours of the day and night. That story got spoilt when one their bitches was in our garden and would not go back to theirs despite her puppies wanted feeding, they came round and knocked on our door asking if they could come and get their dog so the puppies could be fed  :-DD
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Online mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2992 on: October 20, 2017, 01:48:44 am »
Nice! Maybe you'll get lucky again and be uncontested.

I can hope, but i really must quit looking at ebay now. She's tying the noose and picking the tree to use the next time i say ebay.  :-DD

Must... resist... urge... to be... a sniping... douchepuppet... AAARRRGGGHHH!


Because it starts counting at zero, duh. ;)


mnem
There are 10 kinds of people in the world; those who don't understand binary and those who get their heads bashed in for making stupid binary jokes.

Try again. This isn't fencepost errors, it's an instrument that operates in the time domain; it's a counter/timer.

I shall resist linking the obvious picture of Bob Widlar.

 :palm:   ::)  :palm: FFS man... How much more obvious do I have to MAKE it? Do I have to write "<~~~ THIS IS A JOKE!!!" next to it?!?


What have cats done to you? my cats are not like that at all, they are very clean and loving animals.

Er, no.

People worry about infections from dogs, so now dog owners carry their shit around in their pockets. But for some reason they ignore toxoplasmosis gondii from cats. The lifecycle is https://www.cdc.gov/parasites/toxoplasmosis/biology.html

Solid estimates are that 60m (~20%) of people in the USA are infected (95% in some places). It is symptomless except when it isn't - but why worry, heart/brain/eye damage only occurs much later, so the cause can't be isolated and the owner prosecuted. https://www.cdc.gov/parasites/toxoplasmosis/gen_info/faqs.html

The effect of t. gondii in the other host, rats, is "entertaining": it suppresses rats' fear so that they become more likely to eaten by cats, thus completing the lifecycle. There is inconclusive suggestive evidence that t. gondii has mind-altering affects in humans, viz schizophrenia, bipolar disorder, cognitive defect. However, t. gondii  does stop humans smelling cat urine, so maybe it is only a matter of time before a causal link is shown. https://en.wikipedia.org/wiki/Toxoplasma_gondii

And lets not forget good ol' salmonella from handling reptiles and terrapins. I can't count how many times I've seen baby turtles and geckos, frilled lizards, chameleons etc. kept in childcare and educational environments.  :palm:


That too.

Also: http://theoatmeal.com/comics/cats_actually_kill


  <~~~ THIS IS A JOKE!!!


mnem
A pet shop owner receives a visit from a distraught mother; the box turtle she'd bought for her son mysteriously developed open sores on its feet the next day. He inspects the animal, and sure enough it's feet are raw and oozing, so he places it in quarantine and gives her a new turtle for her son. Relieved, she takes the creature and leaves.

The next day, the mother AND her son return; he's crying and this turtle ALSO has sores on its feet! Now the shop owner is almost in a panic; he figures the whole lot has some weird disease he's never heard of, so he puts the turtle in with the other in quarantine, washes his hands carefully, and selects one of the prettiest looking painted turtles he has from a completely different breeding lot and hands it to the now very excited little boy, who immediately drops down on his knees and begins to play with it.

"VROOOM! VROOOM!!! TURTLE TRUCK!!!" The child exclaims gleefully, racing the turtle around himself on the floor in circles...


THAT WAS A JOKE TOO!
« Last Edit: October 20, 2017, 01:58:18 am by mnementh »
 

Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2993 on: October 20, 2017, 02:09:02 am »

Because it starts counting at zero, duh. ;)


mnem
There are 10 kinds of people in the world; those who don't understand binary and those who get their heads bashed in for making stupid binary jokes.

Try again. This isn't fencepost errors, it's an instrument that operates in the time domain; it's a counter/timer.

I shall resist linking the obvious picture of Bob Widlar.

 :palm:   ::)  :palm: FFS man... How much more obvious do I have to MAKE it? Do I have to write "<~~~ THIS IS A JOKE!!!" next to it?!?


I did genuinely consider that possibility, but as it wasn't even remotely funny I just assumed the smiley was random punctuation. In case you hadn't noticed there's a lot of that on here. There's one poster, who shall remain nameless, who manages one smiley for every sentence (or sentence fragment) while studiously avoiding initial capitals, full stops, or any other recognised conventional punctuation (and for the most part also eschews sense, but that's another matter).

So, sorry, you got caught in the signal to noise ratio, but it helps if you make your humour erm, well, ya know,  funny. Chacun à son goût and all that but still...
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2994 on: October 20, 2017, 03:07:24 am »
Well this thread has gone down the swanny recently. Cats and obscure humor.

Time for some high quality hardcore test gear porn to liven it up: http://www.hparchive.com/wallpaper.htm
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2995 on: October 20, 2017, 03:30:36 am »
Argh here we go again! It went like this:

1. Wooh this thread is getting lame.
2. Let's throw some HP porn on it.
3. Wow those HP/Harrison power supplies look nice. Have been on my mind for a few days.
4. I really miss my HP6236B. Boo hoo  :'( ... But I need something with some more voltage for building high compliance voltage current sources with.
5. Let's have a look on ebay and cheer myself up with some luck.
6. Nothing in the usual categories. Let's just try searching for what I want in some vein hope that it will exist.
7. IT EXISTS but the price is a little higher than I was hoping.
8. Meh feck it, it's like two curries and all I do is turn them to poop.
9. Now I own a 6206B :)



 

Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2996 on: October 20, 2017, 04:01:43 am »
Nice, old school metering but thats not a bad thing, its quicker to read at a glance. ;)
Who let Murphy in?
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2997 on: October 20, 2017, 04:23:28 am »
Yep exactly that.

I've got three digital display supplies and one analogue metered supply and I've got to be honest, most of the time when I'm developing circuits, the set voltage isn't all that important as long as it's ball park in the right area. The thing that is important is current trends which you can't visualise easy on a digital display especially if it's jumping around all over the place.
 

Offline URI

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2998 on: October 20, 2017, 04:57:41 am »
Argh here we go again! It went like this:

1. Wooh this thread is getting lame.
2. Let's throw some HP porn on it.
3. Wow those HP/Harrison power supplies look nice. Have been on my mind for a few days.
4. I really miss my HP6236B. Boo hoo  :'( ... But I need something with some more voltage for building high compliance voltage current sources with.
5. Let's have a look on ebay and cheer myself up with some luck.
6. Nothing in the usual categories. Let's just try searching for what I want in some vein hope that it will exist.
7. IT EXISTS but the price is a little higher than I was hoping.
8. Meh feck it, it's like two curries and all I do is turn them to poop.
9. Now I own a 6206B :)

Nice catch!  :)

my variation of that scheme:
1. too much cat-stories at the time...
2. reading service manual of my PM6685 frequency counter to find out about calibration procedures
3. find the information that a 50MHz signal source/function generator is needed at some point
4. state the fact that my HP 3325B only goes up to 21Mhz (sine, other wave forms less)
5. research HP instruments with HP-IB/GPIB and input for external reference
6. stumble over an ebay auction for a 3335A without options in germany with defective sweep out
7. casually bid on it
8. now I own a HP 3335A
9. added HP3335A to my repair queue  :palm:

Will it be worth the 211,- Euros? I hope so, it's in reasonable shape with feet on it.


Reading service manuals is kind of dangerous, am just looking over the one for the HP 3335A..   :scared:  :-DD

edit: fixed the image link.
« Last Edit: October 22, 2017, 08:00:30 am by URI »
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Offline Berni

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #2999 on: October 20, 2017, 05:14:09 am »
Alright then here is some more TEA stuff.

I picked up a Keithley 617 Electrometer on ebay. Listing said that the voltage output is broken but it otherwise works.



Few weeks later it arrives and i hear a noise inside of it if i move it around. Also it was 110V and no external switch to take care of it so it was a case of "Don't turn it on, take it apaaaaart" :-/O



Getting to see the nice front end magic there, but i start finding screws laying about in places, the top analog board was barely held in as half of its screws came out. So i kept taking it apart to find all the remaining screws.



Got a nice look at the front panel too, no runaway screws there.



Got the whole thing out and indeed found some more of the screws under the main board



Once i was sure there are no screws left in there i assembled it back together and turned in on for the first time! Aaaand its reading OL on all ranges.  :--

Well then... Out comes the multimeter and the manual. Checking all the voltages is a bit annoying, as none are marked where they are, so you need to look at the schematic for that. Turns out they are all there except for the +/- 110V rail. This rail runs the 0-100V output on the back so that would explain why that does not work, but it has nothing to do with the ADC or the front end so it should not make it read OL all the time.

I cobbled together a ribbon cable extender so i could power it on and probe things with the upper analog board out of the way. Everything seamed fine until i stuck my probe on to the ADC clock line. It was moving but rather chaotically with weird sloping rise times. Tracing it back shown the same weird chaotic clock at the crystal oscillator circuit. To quickly test this i soldered a wire to the oscillator circuit and injected my own square wave of the right frequency and suddenly the display starts showing numbers! The only problem is that the crystal is a rather oddball frequency of 1.2288 MHz. Eventually i found one on ebay that was salvaged out of gear, it was even in this gigantic can package that fit the footprint!



After finally getting it i put it in and there we go it works! Next is the 110V rail for the voltage output feature. Probing around has shown that the winding on the transformer for that rail is completely dead. Fixing a transformer is not easy and its not easy to find a replacement so instead i went for adding a new transformer just for that rail.



This instrument has a bit of a weird arrangement inside where the big main transformer is run off mains and has electrostatic shielding and produces a 9V AC supply that goes to the 2nd smaller transformer on the analog board where all the analog voltages are generated. These voltages then feed back down to the main board to power the analog parts of the ADC. Very convoluted power arrangement. Because of this what i did instead is get a 24V transformer brick and stick it reverse on this 9V AC output to boost it up to roughly 110V after messing with the taps a bit. This was then given a filled out notch to snugly fit on the top of the existing transformer before getting glued and zip tied down.



And there we go. The entire unit put back together and she works like a dream now!



Here it is showing a zero offset current of 0.0026pA . That is 2.6 femtoamps!
« Last Edit: October 20, 2017, 05:22:23 am by Berni »
 
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