Test Equipment Anonymous (TEA) group therapy thread

[tggzzz]

(SNIP)

In other news, yesterday's GAS was yet another 465, this one with intact feet, two nibs on the cover, and it basically works. OK, some of CH1's ranges are peaky/touchy, and the trigger only works for >0.5 divisions, and some pots are scratchy, but with luck those should be fixable...

Famous last words... 

mnem
Best of luck, brother. See you on the other side.

For once it was better than I expected...

The LT power supplies were OK, and all had <500uV ripple.

The motor works fine.

Found scratchy pot couldn't b cracked open for some fader lube - but it didn't matter since rotating it a few times made it acceptable again.

I expected the twitchy/peaky CH1 deflection to be an attenuator problem. After cleaning the attenuator switches (an easyjob with IPA and a piece of paper), I noticed the problem appeared/disappeared when I attached/moved the input cable. So I heated all the flying solder joints between the input BNC connector and the attenuator board, and so far it is rock solid.

The trigger was, as I hoped, simply a case of tweaking the trimpots.

A final tweaking of the Y output amplifier's many Rs and Cs, and it shows a really nice 3.5ns risetime.

Job done, and without touching my parts mule. Now to get rid of it somehow

Are you going to do a beaded tant replace or just run until magic smoke? 

Let me rephrase that question...

Am I going to replace lots of awkward to get at caps, probably damaging circuit tracks by the big electrolytics, to attempt to reduce the ripple below its existing very low value? Hmmm. Difficult decision.

With the exception of Rifa delayed action smoke generators, if it ain't broke then don't fix it

[bd139]

Indeed. The last one I “shot gunned” was because there was a difficult to find one. Once I’d found it I stopped.

The 7L12 was fun. I did board level isolation until I found it. That wasn’t powered up once before it was fixed

[Kosmic]

geeeeeeze!   no wonder I stuck almost exclusively with hp.

that is a fugly pile o junk!

edit - hope saying that does not make inverted wanna' hunt me down and whoop my fat ass.   but geeeeeeeze!

Almost bought a AC meter from that series once. Specs were really interesting but when I saw what they look liker I changed my mind 

I guess I'm a superficial person 

[Kosmic]

Case sheets can be washed in the dish washer machine.

Interesting. Never thought of using the dishwasher.

As usual you did a really good job 

[Kosmic]

I'm ecstatic, the wife is leaving with her mother for a week and they are bringing the kids!

I'm going to be home alone for a week, incredible. It's going to be freaking TEA time. I need to do a list of everything I want to get done. Need to order some parts in advance. I have to take some time off from work. I would need to cut on sleep. Need to check if I can find something at the drugs store for that.

[bd139]

I need a week like that 

May I suggest:

[mnementh]

Are you going to do a beaded tant replace or just run until magic smoke? 

Let me rephrase that question...

Am I going to replace lots of awkward to get at caps, probably damaging circuit tracks by the big electrolytics, to attempt to reduce the ripple below its existing very low value? Hmmm. Difficult decision.

With the exception of Rifa delayed action smoke generators, if it ain't broke then don't fix it

Indeed. The last one I “shot gunned” was because there was a difficult to find one. Once I’d found it I stopped.

The 7L12 was fun. I did board level isolation until I found it. That wasn’t powered up once before it was fixed

B-B-But... but... but...








mnem
*tantric*

[bd139]

I hate cats so I hit the nail on the head 

[tggzzz]

I am thinking of the kittens, and unless I get a rat problem, I'm not going to change.

Besides, my daughter's dog is a natural born ratter. His only problem is that he's never been anywhere where he can get to them (neither could a cat).

[Kosmic]

I need a week like that 

May I suggest:

Good idea will by a case at costco.

[Martin.M]

that HP54601A + 7475A Plotter Experiment:
I found a setup to print the amplitude in a second color, very amazing 
waiting time for the page: only 10 minutes.

Martin

[mnementh]

I hate cats so I hit the nail on the head 

Nobody hates a kitten.

mnem
"What's with the cat?"
"There's a problem with the cat... sign here."
"What's the problem?" *scribbles signature on release form*
"It's your problem." *sardonic grin*
"I hate the living..."

[Martin.M]

cats are nice but not esd conform.
Martin

[Kosmic]

cats are nice but not esd conform.
Martin

 

[bd139]

Nobody hates a kitten.

One pissed in my scope once and then went for my eldest and scratched her face up. She was 1. That was the last cat we ever had. Fuck cats and kittens. Nasty nasty animals. They kill all the wildlife, bring dead stuff into the house and carry nasty diseases like toxoplasma gondii, leave hairs over everything, walk all over your shit while you're in the middle of it and cost a fortune to keep running.

[mnementh]

You can swap child and kitten word for word in that statement and it's still absolutely true.

Dogs are simple. Cats are complicated. Kittens are adorable, even when they're barfing in your shoes. 

mnem
Just like all babies.

[Cubdriver]

Nobody hates a kitten.

One pissed in my scope once and then went for my eldest and scratched her face up. She was 1. That was the last cat we ever had. Fuck cats and kittens. Nasty nasty animals. They kill all the wildlife, bring dead stuff into the house and carry nasty diseases like toxoplasma gondii, leave hairs over everything, walk all over your shit while you're in the middle of it and cost a fortune to keep running.

Points one and two are moot if they're kept inside (my five are; they're on the food chain here, but woe betide any mouse foolish enough to enter my abode), point three hasn't been an issue in my experience (clean the litter boxes frequently), points four and five I'll grant you, and point six has not been my experience either.  YMMV. I'll keep my cats, thankyouveryplease.

-Pat

[mnementh]

cats are nice but not esd conform.
Martin

    Also reverse-deficient.

mnem
*Caressing the Tiger*

[Specmaster]

Nobody hates a kitten.

One pissed in my scope once and then went for my eldest and scratched her face up. She was 1. That was the last cat we ever had. Fuck cats and kittens. Nasty nasty animals. They kill all the wildlife, bring dead stuff into the house and carry nasty diseases like toxoplasma gondii, leave hairs over everything, walk all over your shit while you're in the middle of it and cost a fortune to keep running.

Points one and two are moot if they're kept inside (my five are; they're on the food chain here, but woe betide any mouse foolish enough to enter my abode), point three hasn't been an issue in my experience (clean the litter boxes frequently), points four and five I'll grant you, and point six has not been my experience either.  YMMV. I'll keep my cats, thankyouveryplease.

-Pat

Cats are loving creatures if you look after and treat them properly but like any animals, including us, can be vicious if ill treated, it's called self protection and sometimes children can be cruel. This is very true if they have not been brought up with animals.
My cats don't kill wildlife, they play with the squirrels and birds just ignore them.  Keep their litter clean, have gad cats all my life and no one has ever suffered as a result. I think it's like a lot of things, yes these problems can happen if not cared for and people tend to jump to the worst examples that have been reported in the press. Cats lower blood pressure and reduce the chances of having a stroke and generally have a calming effect on people, especially the ill and old. I love my two and just like people, their trust has to be earned.

[Martin.M]

my hard working oldie laboratory is proudly presenting

THE PLOTTER MOVIE 

Please do not watch it by handy when you have to pay for the download data, it requires 1GB. (we love full HD + quality)

http://www.wellenkino.de/video/54601A_7475A.mp4

greetings
Martin

[Kosmic]

so now the objective is to put the OCXO in a case as a standalone 10MHz reference which I can plug into the TF930.

Hey I'm working on something like that. but i'm adding a video distributer (swaped the 75Ohms resistors for 50Ohms) in the box to connect multiple devices. Mostly working on the bench but still need to find a standalone power supply and the enclosure.

Will post some pictures soon.

Change of plan! The video distributer conversion worked but I discovered it's limited to something like 5Mhz. I also just bought a 10Mhz rubidium clock.

So the new plan is to swap the ocxo for the rubidium clock, adjust the power supply from 12v to 24v and design the distributer myself.

Hope it's all going to fit in the Hammond enclosure I bought for this project.

[tggzzz]

my hard working oldie laboratory is proudly presenting

THE PLOTTER MOVIE 

Please do not watch it by handy when you have to pay for the download data, it requires 1GB. (we love full HD + quality)

Those plotters always were hypnotic to watch. I remember drawing presentation slides (Powerpoint? Wassat?) on them; watching them block fill an area was fun, but that did use ink up faster.

What do you use for ink/pens now - I guess they are in short supply.

[bd139]

I'm liking the plotter subject at the moment.

One of my fondest memories was I think circa 1988 at college. We had the "technology club" in which we got to piss around in the labs and build whatever we wanted basically. This exposed us to a pile of test gear, dangerous chemicals (we had a PCB fab at hand!), spanking new BBC Masters, several hundred quid's worth of lego and some Dacta control boxes. And this gem in a book:



The software that came with it was crap so I had the fun job of writing something. It was mostly BBC BASIC nudging bits in the user port but some of the loop based timing routines weren't very precise so the kettle and the inline assembler was fired up. I ended up inventing a control language for it which wasn't that far off postscript which was funny because I had never seen postscript before then.

The result after several evening's work?



 

(but I learned a lot and got to play with lego)

Edit: with respect to pens we used Berol felt tips, attached with a rubber band with a load of blu-tack around them to give them some mass 

Edit 2: also a minor flashback. We used to steal stacks of electronic components from the college stock room. They knew, to the point one of the tutors said he did and that he'd face the other way and read his newspaper while we helped ourselves, because it kept their budget for tech department allocated

[0culus]

Oh man, Legos...I have a "significant" collection of them... 

[jlw]

I have enough counters already, don't I?

 

Is there such a thing? 

For a non Freq/Ham I am happy with my current five (3 of which were because of Nixie'itis) add to that a couple of fairly capable Arb generators with Freq inputs. That then led to a GPSDO and more recently an RF Generator in the fleet to help keep them in tune and now I am looking at ..... 

For my defense and additional fright, see the counters and sources here: http://web.jlw.com/test.html