Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 14407599 times)

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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107725 on: November 26, 2021, 08:08:01 pm »
Hey Med, is that mess in the scope not just sawdust ?

Maybe it is, maybe it isn't. Who the freak knows until I start cleaning. But it DOES stink so I suspect more than "just" sawdust.
Some woods do stink as you know but the smell is normally lost after a while as sawdust. Maybe a rat pee'd on the scope and it soaked some in to retain the stink.
Anyways it's probably been stored in a small workshop to get such a coating of dust.....I'm sure it will be just fine Med.

If you think that's bad you should have seen the state of aircooled avionics equipment back in the days when they allowed smoking on aircraft....

If you think that's bad, you should try rummaging around for truck-cab components in an inch of green liquid charitably described as "decomposing animal proteins". I can still remember the smell, and that was more than 30 years ago...

Ugh, I've been behind a knackers truck on the road before. You can still smell them miles after you have passed.

Indeed. A school we recently finished a (protracted) rewire on is on the route of a local "protein" producer. Several dozen trucks a day go past, both fully laden and "empty", and one morning I arrived to the delightful sight of a literal pile of sheep guts on the road where I wanted to park.
I adjusted my parking accordingly; one of the subbie joiners did not. I dread to think what his drive home was like...
nuqDaq yuch Dapol?
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107726 on: November 26, 2021, 08:13:42 pm »
Cool, I haven't seen a chess computer for years. I used to have one, but cannot remember what happened to it  :palm:

Did you pawn it? You should rook in the attic, it knight be there. You really should check, mate.


mnem
"I... I... I just can't... There isn't enough stockpile to mount an appropriate response; I'd have to import boatloads of soggy ol' boots from England, just to lob them all back across the pond..." :o

I make no apologies.

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mnem
I think this may be a job that's better outsourced... Saskia, how's your supply of special teddy bears...?
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Offline factory

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107727 on: November 26, 2021, 08:20:24 pm »
Mine is easy to work out, but "factory" on it's own was already taken.

Yeah, I think I may have cost you a fair bit and vice versa.  :-\

I guess you bid on the 745A, which cost more than the Fluke equivalent (I didn't bid for any of those), as I see you bought must of the other calibrators? I left most of my bids last night, didn't see ice-tea on any of them, but lots of bids from lightstream & astonline, didn't win all of them.

David
 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107728 on: November 26, 2021, 08:22:43 pm »
Oh, and the stupidly cheap GenRad LCR arrived. It's currently toasting off the seasonal delivery condensation by the fire. I'll give it a poke with the mains in a bit.
Weighed in a small quantity of offcuts today, sandwich money for all the team next week...

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Snow is forecast for here tomorrow night. CR-V sez "bring it".  ;D
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107729 on: November 26, 2021, 08:31:10 pm »
This has to be the oldest Solartron I've seen so far: https://www.ebay.co.uk/itm/334232124623

Hmmmmm... I do believe I see 3DP spacers made to refit that with modern output terminals and color coding. While I personally couldn't care less, it does set off the ol' anachronism detector something fierce...  :o

Another thought... do we really know if that was even made by the same Solartron we know & love for their "special" connectors...?

mnem
no  :popcorn:  for me...

Yes. https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=8231

Looks to be a newer version of the SRS153 here;
https://www.vintage-radio.net/forum/showthread.php?t=160377

The terminals might be replacements but I doubt the spacers are 3DP, but they are fairly old too, probably the sort RS components used to sell.
Note: these are unregulated PSU's.

David


When you've made a bunch of little bits & bobs like these spacers, you get a pretty good feel for what the finished surface looks like and how light bounces off it, or doesn't. I'll admit the pics are just too rubbish to be sure; but my gut reaction, especially looking at these two pics, is 3DP spacers made to use up some old terminals somebody had in the parts drawer.

mnem
« Last Edit: November 26, 2021, 08:35:46 pm by mnementh »
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Offline Andrew_Debbie

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107730 on: November 26, 2021, 08:37:15 pm »
 

Online Robert763

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107731 on: November 26, 2021, 08:39:08 pm »
So I can't give away a TF2730 SA on here but PP auction one for £51 plus mark up plus VAT =£70  :wtf:  :-//
 

Online Ice-Tea

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107732 on: November 26, 2021, 08:44:44 pm »
I guess you bid on the 745A, which cost more than the Fluke equivalent (I didn't bid for any of those), as I see you bought must of the other calibrators?

Got a Fluke 5100 and 5200.

Quote
I left most of my bids last night, didn't see ice-tea on any of them,

Nah, didn't bid untill today. Say summethin summtehin factory a few times. Never connected the dots.

Quote
but lots of bids from lightstream & astonline

those guys went to town.

David
[/quote]

Offline factory

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107733 on: November 26, 2021, 08:53:59 pm »
Not heard of this manufacturer before, no doubt Robert, Cerebus, or tggzzz can elucidate: https://www.ebay.co.uk/itm/224708780108

Not me.

Someone's going to have fun with that mains cable.

I've seen a DVM & another of their counters sell locally, were too much for me, info is lacking too, only found some advertisments here (post 5), SM202 is 8 digit 150MHz;

https://www.vintage-radio.net/forum/showthread.php?p=659238

The mains lead clamp is the same as older Solartron TE used, they are often pulled out as seen it the sellers pictures.

David
 

Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107734 on: November 26, 2021, 09:02:22 pm »
7000 recorder
https://drive.google.com/file/d/1vSLl92J68OgTXttoL2nugCa_MGHp0d3w/view
Seems Penny and Giles took them over from EMI.
Their recorders were used for early "digital" (recording was FM) audio work at Abby Road Studios

It says "portable". For Geff Capes maybe. Damm things are at least 43kg (95 lbs). They are a awkward shape / size too.

A question of degree I think. The Studer A80 1/4" machine weighs in at 96.5kg.
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Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107735 on: November 26, 2021, 09:07:52 pm »
Thanks, OK so  the 53132A is basically a better performing counter than the 53131A, no downsides !  8) So worth getting if can be found for a similar price as the 53131A.

If you find one without any of the OCXO options, just with the internal XO, you will want to upgrade the timebase. The basic XO is about as nasty as they get, I think basically they include it so it worked out of the box (but cost HP little in BOM terms) for people who were only ever going to feed it from an external reference clock. If you bought one without an option card and didn't have an external reference source you'd be back to buy an option card ten minutes after you'd first turned it on. There are several designs kicking about for DIY OCXO upgrades for the range, including GPSDO ones. With one of the OCXO options it's a fine counter, the top end option (Ultra Stable) is very, very stable, mine drifts considerably less than the specification when compared long term (a week or more) with GPS.



OK OK ! Wow, no less than 3 OCXO options to choose from, something for everyone !  ;D

As I said in a previous post the idea is to get an external 10MHz reference in the lab, so that I can feed it to all my counters present and to come, modern or vintage, and any other piece of gear that might benefit from it (SA ?), or even just use as test signal why not. This way I can select the best 10MHz ref for my budget, performance "requirements", power consumption (since it's gonna be on 24/7 obviously, need to pay attention to that...a 100 Watt ref is not gonna be acceptable). This way I don't have to spent ages to and waste lots of money finding and buying a counter with a rare ultra high stable OCXO, for starters. I can just get the cheap versions of the counter, that are readily available, and call it a day. Also, if I later upgrade the external ref to god knows what, better spec, then all my counters instantly benefit from it.

That's the plan anyhoo !  ;D
 

Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107736 on: November 26, 2021, 09:25:48 pm »
Counters : just received my little miniature counter !  ;D

Well it's not as minuscule as I thought... it's twice bigger and 10 times heavier than I thought it would be.

The 7 Miniton displays all work like new, super bright and even brightness, razor sharp digits, beautiful to look at. Not as tiny as expected either. IIRC datasheet said 8mm tall digits, I measured it at 10mm, 25% more !  ;D 

The red LED in the top left corner above the power switch... it's not  a power-on status indicator, nope.... it's the status LED for the OCXO ! LED goes on and off constantly, as the thermal regulation goes on. It's lit for 3 to 5 seconds at a rough guess, then unlit for about the same amount of time, etc.. keeps blinking at you. So cool, it's like you had an X-ray camera to monitor the heart of the instrument in real time, gives a feeling of involvement, such a nice touch.

The display is updated once per second it seems, something like that.

I am glad I bought it, it's really a cute little thing !  :D

Might benefit from a light cosmetic restoration though... a good clean to begin with of course, but a repaint as well maybe. The blue top/bottom covers are so poorly painted, or maybe it's rust bubbles, that it looks like crinkle paint or something !  ;D 
Might sand it down and repaint it black. Front bezel black as well with white lettering, would make the Minitron displays stand out even more, they would be the star of the show.

Could do with new BNC sockets as well, they look crusty....


Anyway, will leave it like that for now and the foreseeable future...

Tested it, works fine no worries...

« Last Edit: November 26, 2021, 09:46:12 pm by Vince »
 
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107737 on: November 26, 2021, 09:43:49 pm »
If I lived closer . . .

https://www2.ppauctions.com/lot/161429/lot-181
https://www2.ppauctions.com/lot/161449/lot-201
https://www2.ppauctions.com/lot/161493/lot-245


Outbid but not by much. . . 
https://www2.ppauctions.com/lot/161463/lot-215

Missed this one...
https://www2.ppauctions.com/lot/161568/lot-320   -  I can't tell if it has option 04 but even if it didn't....





How are you getting this information? I registered but forgot to bid on the voltage divider and the Heathkits but I'm unable to get anything on screen when I log back in again, all the watched items have been erased.
Who let Murphy in?

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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107738 on: November 26, 2021, 10:12:17 pm »
If I lived closer . . .

https://www2.ppauctions.com/lot/161429/lot-181
https://www2.ppauctions.com/lot/161449/lot-201
https://www2.ppauctions.com/lot/161493/lot-245


Outbid but not by much. . . 
https://www2.ppauctions.com/lot/161463/lot-215

Missed this one...
https://www2.ppauctions.com/lot/161568/lot-320   -  I can't tell if it has option 04 but even if it didn't....

How are you getting this information? I registered but forgot to bid on the voltage divider and the Heathkits but I'm unable to get anything on screen when I log back in again, all the watched items have been erased.

Either keep bookmarks in your browser, or use arithmetic to derive the URL from an item you won. For example,lot 319 would be https://www2.ppauctions.com/lot/161567/lot-319
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107739 on: November 26, 2021, 10:38:37 pm »
If I lived closer . . .

https://www2.ppauctions.com/lot/161429/lot-181
https://www2.ppauctions.com/lot/161449/lot-201
https://www2.ppauctions.com/lot/161493/lot-245


Outbid but not by much. . . 
https://www2.ppauctions.com/lot/161463/lot-215

Missed this one...
https://www2.ppauctions.com/lot/161568/lot-320   -  I can't tell if it has option 04 but even if it didn't....

How are you getting this information? I registered but forgot to bid on the voltage divider and the Heathkits but I'm unable to get anything on screen when I log back in again, all the watched items have been erased.

Either keep bookmarks in your browser, or use arithmetic to derive the URL from an item you won. For example,lot 319 would be https://www2.ppauctions.com/lot/161567/lot-319
Oh I see, thanks for the info  :-+
Who let Murphy in?

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Offline bitseekerTopic starter

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107740 on: November 27, 2021, 12:13:28 am »
Thanks, OK so  the 53132A is basically a better performing counter than the 53131A, no downsides !  8) So worth getting if can be found for a similar price as the 53131A.

If you find one without any of the OCXO options, just with the internal XO, you will want to upgrade the timebase. The basic XO is about as nasty as they get, I think basically they include it so it worked out of the box (but cost HP little in BOM terms) for people who were only ever going to feed it from an external reference clock. If you bought one without an option card and didn't have an external reference source you'd be back to buy an option card ten minutes after you'd first turned it on. There are several designs kicking about for DIY OCXO upgrades for the range, including GPSDO ones. With one of the OCXO options it's a fine counter, the top end option (Ultra Stable) is very, very stable, mine drifts considerably less than the specification when compared long term (a week or more) with GPS.



OK OK ! Wow, no less than 3 OCXO options to choose from, something for everyone !  ;D

As I said in a previous post the idea is to get an external 10MHz reference in the lab, so that I can feed it to all my counters present and to come, modern or vintage, and any other piece of gear that might benefit from it (SA ?), or even just use as test signal why not. This way I can select the best 10MHz ref for my budget, performance "requirements", power consumption (since it's gonna be on 24/7 obviously, need to pay attention to that...a 100 Watt ref is not gonna be acceptable). This way I don't have to spent ages to and waste lots of money finding and buying a counter with a rare ultra high stable OCXO, for starters. I can just get the cheap versions of the counter, that are readily available, and call it a day. Also, if I later upgrade the external ref to god knows what, better spec, then all my counters instantly benefit from it.

That's the plan anyhoo !  ;D

Yep, for TEA, it makes sense to have a central frequency reference for all the clock-based things: scopes, counters, spec analyzers, etc., etc. Not only does it save on cost and power, as compared to individual OCXOs in all the things, but they all stay in sync, too. And then, you eventually find that you've run out of channels on the 10 MHz distribution amp. :-DD
« Last Edit: November 27, 2021, 12:15:29 am by bitseeker »
TEA is the way. | TEA Time channel
 
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107741 on: November 27, 2021, 02:19:45 am »
Todays crazy eBay valuation  https://www.ebay.co.uk/itm/392307906399

I think the original price new was around £500 and has recently been discontinued, so this price is utterly stupid.
Who let Murphy in?

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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107742 on: November 27, 2021, 02:48:43 am »
@Cerebus, did you ever manage to get your hands some wiper blades from Home Bargains in the end? If not they have some in Lidl's at the moment but best move fast as they won't be around for long.

No, and "that was ages ago". I did actually put some new blades on for the winter the other day, modern whooshy aerodynamic one-piece ones from Lucas.

Lucas?  :o Don't use them in the dark.  :P :-DD

Son, I say son, if your wiper blades help you to see in the dark then we're back to them ray-dee-O-active materials and them's not what you're wantin' to be makin' wiper blades, I say wiper blades, from.



Here in the "land of sun, sand, sin & sore eyes", we use wipers at night (in conjunction with washers) to remove the days accumulation of dead insects (a different shift of such critters takes over after nightfall).

A smeary windscreen at night is not a good thing when something nearly the size of an express train approaches, with "more lights than you can poke a stick at", all adding their blinding bit to what suddenly goes from a windscreen to a lunatic display screen, with all the insect guts adding their bit to the horrible total.

Will he dip?---maybe!

Even if you avoid that, you get 4WD nuts with high beam plus multiple lights on a light bar!
 
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Online Vgkid

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107743 on: November 27, 2021, 03:01:41 am »
Oh, and the stupidly cheap GenRad LCR arrived. It's currently toasting off the seasonal delivery condensation by the fire. I'll give it a poke with the mains in a bit.
Cool, those were pretty simple machines to use, now my 1689 was not as easy.
Does it have the slide out quick start sheet, like my other digibridges have?
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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107744 on: November 27, 2021, 03:07:19 am »
Oh no.... this one just popped up here :

https://www.leboncoin.fr/bricolage/2077988887.htm

An interesting one I can't have !  >:(

...

Well I guess that's OK.... let's see the positive side : it evidenced my growing interest for old HP stuff.... so now I will be on the lookout and maybe search actively for cheap interesting pieces like this one, and start a little collection....just a handful of items, not more, promised... and no boat anchors (NO vintage two piece spectrum analyzer or such !  :-DD  ).
So that was my " HP coming out " I guess ?!  Great, like I was not in enough trouble with my glowing Tek scope addiction... now I am getting into HP stuff as well.... I am in great danger, I really am  :palm:




Yep, HP/Agilent made lots of nice little things to collect. I got bitten by that bug before Tek. ;D

Note that the 3310A and 3310B are 5 MHz generators (not just 1 MHz) -- not that you needed any more reason to get one.

Oh you are right, 5MHz not 1MHz !  Google told me 1MHz !  :-- ... but looking at the pic more closely, highest range is 100kHz and main dial goes up to 50 !  8)   Hmmm... I need to find a reason not to buy one... Oh I found something ! It does NOT have an attenuator !  ;D
MY old Philips has three 20dB attenuators, so up to 60dB, which I do find very practical.
Next collection---standalone attenuators!
 
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Offline xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107745 on: November 27, 2021, 03:10:19 am »
Todays crazy eBay valuation  https://www.ebay.co.uk/itm/392307906399

I think the original price new was around £500 and has recently been discontinued, so this price is utterly stupid.

No pics of it turned on, no pics of it measuring anything ... I don't get why people present these instruments like that.  :palm:
I told my friends I could teach them to be funny, but they all just laughed at me.
 
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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107746 on: November 27, 2021, 03:13:48 am »
MY old Philips has three 20dB attenuators, so up to 60dB, which I do find very practical.
So does mine although I wouldn't even dream of using the old POS these days.
They are not just yesterdays technology but mid last century.

Was very temped to pop it the inorganic recycling a couple of weeks back.

Even back in the old days, the name "Philips" often made many of us think of that option!

They were like "the little girl with the little curl, right down the middle of her forehead"----when they were good, they were very, very, good, but when they were bad, they were horrid!
 
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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107747 on: November 27, 2021, 03:34:05 am »
Vince,
I got the control panel out. All the minitrons work but one looks a bit dim. Don't know if it's a display or drive issue. They are socketed so easy to find out. You only need four for a clock It has a greenish night vision goggle (NVG) compatible display filter this needs a clean.
It does have a fault, it looks like the on/off/function switch is faulty. There is an internal 12V regulator and if I put voltage on that it works but there is no continiuity between the regulator positive input and any pin on the connector (pin U is 0V).
Additional good news is that I have manuals that include details of an internally identical control head, it just has a different pin out. The logic is all standard CMOS at 12V and would be easy to interface to.
I think it's worth £30
It's just under 1kg packed so postage would be £10
Send me a private messageif interested.

Sounds cool, deal !  :D

Dim display I can relocated in the middle to be the separator between HH and MM. It being dim would then not look odd but might even be seen as a subtle feature. Defective mode switch well according to the diagram all switches including this one are just simple/ basic mechanical switches, not encoders.. so maybe it can be fixed without too much trouble...
Great that you have the diagram for the thing !  So there is no CPU at all in this thing, all discrete logic !  :o
Quite a lot of chips then... and no SMD chips back then I guess... so all DIP packages ?? I am sure it's all very compact in there, but still... I guess this unit is not as tiny as I thought initially from looking at the pic. Maybe it's not the size of a match box after all... maybe it's the size of a match box... and a half !  ;D

So looks like the displays are multiplexed, cool.... not too many pins to interface with then, will make integrating my own H/W in such a cramped space... much easier than I thought. Still very tight I am sure, but feasible at least...well I think... hope.... we shall see how it goes once I have it on my bench ! :-DD

Do yo have a high resolution picture of the diagram ? A bit hard to read as it is.

Can't wait to tear it apart to see how it's put together !  8)

You can start packing the thing, this puppy is now mine....


Ahh you youngsters. Just becuse it has a digital display and a serial data bus output does not mean it has to have a microprocessor. It doese not even have  lot of discrete logic. The rotary switches produce parallel data. This is decoded (multiplexed digit by digit for input as well as display) and decoded for 7 segment display. A PISO shift register takes the same data from the switches and puts it out on  the serial bus.
It is all discrete logic. I'll put the infoI have on a CD for you. I've already soldered a red and black wire to the input of the 12V regulator internally and brought them out under the cover. So just connect those to anywhere between 15 and 28V DC and it will basically work.
Edit: It is all DIL ICs. 3 or 4 small PCBs so not too bad to work on.

ICs? Who needs ICs for digital logic?

The divide-by-10 circuits in the 1965 Tek 184 use only 3 transistors. How do they do that? Having debugged mine, that's a rhetorical question!


What we used to call a "step counter"---syncing a lower frequency astable multivibrator to a higher frequency?
We were taught about these in "Pulse Technology" at Perth Tech College back in 1960/61.

The Marconi TV "OB" SPG we had at PTC, (old, even then) used this method, but proper studio ones from the '50s used cascaded bistables with feedback loops to get weird counts.
Quote

Even earlier was the 1962 Tektronix Type 6R1 plug-in for the 567 oscilloscope. In particular have a look at the "memory" board. Notice how wonderfully ergonomic the displays are.


 

Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107748 on: November 27, 2021, 04:05:47 am »
Just like with the Japs...

I don't know if you realise, but that there's a racial slur...  ;)

Na, just further evidence that Antipodeans feel the need to come up with a two or less syllable shorthand for any word of three or more syllables - I mean, who else would shorten 'afternoon' (and make it easy to confuse with a pear, also shortened because of its terrifying four syllables).  :)

In what alternate universe does "arvo" sound like a pear?

Ohh I forgot!
The UK ---- a universe of its own!

I could imagine that by holding your head "just so", & ignoring  the "r", it could be "Avocado Pear" a strange name which is pretty much obsolete everywhere else.
Why not confuse it with a real Avocado, or a multimeter?

 

Offline cyclin_al

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #107749 on: November 27, 2021, 04:07:02 am »
Also very very interesting.....



I confess my sin, until today I was thinking VxI electric power flows inside the electric cables.

Just ignore the misleading part....  8)

Dave could not ignore the misleading part, and expresses elaborates on it rather well:


I am not sure how the education system in Australia compares to North America, but Dave's "engineering 101" comment I thought should be more like "engineering 205".  I think NA "engineering 301" would be too far a stretch.

Me, being a systems engineer, was thinking the electrical "lumped element" is no different from the mechanical "point load".
Applying some transmission line theory (calculus) is equivalent to finite element analysis (calculus).
I noticed how Dave treated Maxwell and Poynter (ie. coefficient c) as deities; the mechanical equivalents would be Bernoulli, Euler and Young (ie. coefficient E).

-- sorry, my brain should be shut off at this hour of the day
« Last Edit: November 27, 2021, 04:37:35 am by cyclin_al »
 


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