Test Equipment Anonymous (TEA) group therapy thread

[med6753]

@bd139, Great job on that clean up, Bloody gorilla's, they have zero respect for equipment have they 

Definitely....looks tits! 

[Cerebus]

Did someone eye a metal lathe/mill this month ? I am having a case of TES http://www.mini-lathe.com/Mini_lathe/Start/start.htm#tes

TES and TEA are simply two facets of a similar condition. You are in the right place, just keep on keeping on. But do try to up the ante from Chinesium lathes..

The Grizzly minis have a good rep (at least the older ones that still had all-metal gearsets) for being the right mix of inexpensive vs cheaply made. Of course, that has driven the price up to a point where you'll usually be wishing for something a little more capable, unless you can get a steal on one from someone who doesn't know what they are.

mnem

Looking at their current line-up, it looks like Grizzly do the same as Warco here in the UK do. It is a chinesium lathe, but it's a chinesium lathe that they have either souped up after getting them or, more likely, specified a higher grade when ordering them in bulk (e.g. Please fit proper angular contact bearings, not simple deep grove ones to the spindle please, and please grind the rails to a sensible spec, not ± half an inch, etc.)

If you're prepared to treat one of the chinesium mini lathes as a kit of parts, swap the bearings, and do all the fettling yourself you could probably get quite a decent lathe (within the limits of the casting sizes etc.) out of it. Depends whether you feel like spending a few days hand scraping ways and dovetails etc. Of course if one is  going to go to all the trouble of reconditioning a new lathe one might as well bide one's time, pick up a cheap but good old hunk of iron and recondition an old lathe instead. Presupposing that one has the space to put a 'good old hunk of iron' in, if ya don't you're back to the mini-lathe.

[TERRA Operative]

Tektronix TM500. Modular test gear.

Rest of 6206B cleaned up. Some permanent marker and scratches left but better for sure. Took all flipping day to do a 10 minute job 

Before:

After:

Most important thing is it works properly!

Nice work!

I have a slight fetish for old HP gear, it makes me happy and sad so see this sort of thing.
Happy it has been restored and will be put to good use, sad it isn't being put to use on my bench.

[0culus]

The verdict on this Type 3A74 Vertical plug-in.......

I managed to get 4 traces. All unstable with channel 3 being the worst. It bounces where ever it wants to. None will consistently pass a signal although I did manage to get channel 1 to pass something...and then it died. Apparently I'm going to have to dive into the attenuator switch decks and completely clean them too. Oh fun. I was hoping I wouldn't have to. But not today. Got other things to do. Into the repair cue.

So the A trace from my Type CA was doing the bouncing thing, turned out to be the switching multivibrator tube being bad. It stopped when I swapped in another 12AT7.

My planned tactic for working on this is to get channel 1 fully functional all the way to the Vertical output. That way I can use channel 1 as a template and a cross check while troubleshooting the other 3 channels since they are all identical.

That's a good tactic, but I'd still say it's still worth checking the switching circuitry. I have discovered that it can cause trouble in non-obvious ways. 

[med6753]

The verdict on this Type 3A74 Vertical plug-in.......

I managed to get 4 traces. All unstable with channel 3 being the worst. It bounces where ever it wants to. None will consistently pass a signal although I did manage to get channel 1 to pass something...and then it died. Apparently I'm going to have to dive into the attenuator switch decks and completely clean them too. Oh fun. I was hoping I wouldn't have to. But not today. Got other things to do. Into the repair cue.

So the A trace from my Type CA was doing the bouncing thing, turned out to be the switching multivibrator tube being bad. It stopped when I swapped in another 12AT7.

My planned tactic for working on this is to get channel 1 fully functional all the way to the Vertical output. That way I can use channel 1 as a template and a cross check while troubleshooting the other 3 channels since they are all identical.

That's a good tactic, but I'd still say it's still worth checking the switching circuitry. I have discovered that it can cause trouble in non-obvious ways. 

By verifying channel 1 all the way to the vertical output it will automatically check the switching circuits even with the other channels switched off.

[mnementh]

   Did some work on the 6206b this morning. Checked out caps - all good. Calibrated and destickered half of the front. Other half still to go. Annoyed about the scratches from the previous idiot owner who used a screwdriver to get a cal label off.

   I have some MLP stickers here I was gonna give my daughter; I think she can spare a couple for such a noble cause.

So... you want Twilight Sparkle and Rarity or Rainbow Dash...? I'm saving Apple Jack for med. 

mnem
 

[bd139]

Rainbow dash   

[mnementh]

She's on her way, buddy. 

mnem
I know I don't have to ask on Twilight Sparkle... everybody wants her. 

[0culus]

I ordered an HP65/67/97 gummy wheel repair kit from a gentleman who made one up with the right size parts.

[mnementh]

Did someone eye a metal lathe/mill this month ? I am having a case of TES http://www.mini-lathe.com/Mini_lathe/Start/start.htm#tes

TES and TEA are simply two facets of a similar condition. You are in the right place, just keep on keeping on. But do try to up the ante from Chinesium lathes..

The Grizzly minis have a good rep (at least the older ones that still had all-metal gearsets) for being the right mix of inexpensive vs cheaply made. Of course, that has driven the price up to a point where you'll usually be wishing for something a little more capable, unless you can get a steal on one from someone who doesn't know what they are.

mnem

Looking at their current line-up, it looks like Grizzly do the same as Warco here in the UK do. It is a chinesium lathe, but it's a chinesium lathe that they have either souped up after getting them or, more likely, specified a higher grade when ordering them in bulk (e.g. Please fit proper angular contact bearings, not simple deep grove ones to the spindle please, and please grind the rails to a sensible spec, not ± half an inch, etc.)

If you're prepared to treat one of the chinesium mini lathes as a kit of parts, swap the bearings, and do all the fettling yourself you could probably get quite a decent lathe (within the limits of the casting sizes etc.) out of it. Depends whether you feel like spending a few days hand scraping ways and dovetails etc. Of course if one is  going to go to all the trouble of reconditioning a new lathe one might as well bide one's time, pick up a cheap but good old hunk of iron and recondition an old lathe instead. Presupposing that one has the space to put a 'good old hunk of iron' in, if ya don't you're back to the mini-lathe.

Yeah, that was kindof where I was going with my response. Problem is, there's too many professional machine-shop & estate sale scroungers anymore... the days when you just had to scour the swap-sheet for a few weeks to find something worth taking a punt on are long gone; the intardnet has made that kind of scrounging nigh-extinct. 

mnem
*sigh*

[mnementh]

I ordered an HP65/67/97 gummy wheel repair kit from a gentleman who made one up with the right size parts.

Yeah... much as I enjoy the good-natured bickering over calculator logic, for the most part none of them are worth spending any real money to fix them up. Yours is one of the rare few examples that are worth investing a bit.

Keep the faith!

mnem
I just wish I could still read the fukkin' numbers...

[Cerebus]

...find something worth taking a punt on are long gone; the intardnet has made that kind of scrounging nigh-extinct. 

mnem
*sigh*

Says the man who almost literally tripped over two industrial sewing machines on the sidewalk.

[0culus]

I ordered an HP65/67/97 gummy wheel repair kit from a gentleman who made one up with the right size parts.

Yeah... much as I enjoy the good-natured bickering over calculator logic, for the most part none of them are worth spending any real money to fix them up. Yours is one of the rare few examples that are worth investing a bit.

Keep the faith!

mnem
I just wish I could still read the fukkin' numbers...

Agreed...and it's compounded by the fact that the HP-65 is bona fide computer history. It was the first handheld programmable "thing" as far as I know. And one took a trip into space for the Apollo-Soyuz Test Project where the US astronauts actually used it with special programs to perform calculations for the rendezvous.

[nixiefreqq]

I ordered an HP65/67/97 gummy wheel repair kit from a gentleman who made one up with the right size parts.

Yeah... much as I enjoy the good-natured bickering over calculator logic, for the most part none of them are worth spending any real money to fix them up. Yours is one of the rare few examples that are worth investing a bit.

Keep the faith!

mnem
I just wish I could still read the fukkin' numbers...

Agreed...and it's compounded by the fact that the HP-65 is bona fide computer history. It was the first handheld programmable "thing" as far as I know. And one took a trip into space for the Apollo-Soyuz Test Project where the US astronauts actually used it with special programs to perform calculations for the rendezvous.

hmmmmmm.  maybe these gummed up the wheels?

[mansaxel]

Of course if one is  going to go to all the trouble of reconditioning a new lathe one might as well bide one's time, pick up a cheap but good old hunk of iron and recondition an old lathe instead.

Köpings mekaniska verkstads AB (Nowadays the Volvo Powertrain gearbox factory) used to cast the beds of their highly regarded lathes, and then put them out in the yard for a year to stress relieve the casting. Only then were they taken in again and machined. Köping lathes still command impressive prices used.  I've got a 1920s Storebro in pieces. Pretty close to a South Bend, actually. Three speeds on flat belt, and back gear. Three-phase 6hp motor.

Presupposing that one has the space to put a 'good old hunk of iron' in, if ya don't you're back to the mini-lathe.

A big lathe can make small parts. The opposite is not always true.

Today, you get to select between Weiler and Trens. Colchester or Köping is no more. Storebro still sell spares at insane prices. In Sweden, also Blomqvist mini lathes were common. But are quite expensive used. Some spares might be available.

[med6753]

Wow, throw back. Remember this crap?

[0culus]

I ordered an HP65/67/97 gummy wheel repair kit from a gentleman who made one up with the right size parts.

Yeah... much as I enjoy the good-natured bickering over calculator logic, for the most part none of them are worth spending any real money to fix them up. Yours is one of the rare few examples that are worth investing a bit.

Keep the faith!

mnem
I just wish I could still read the fukkin' numbers...

Agreed...and it's compounded by the fact that the HP-65 is bona fide computer history. It was the first handheld programmable "thing" as far as I know. And one took a trip into space for the Apollo-Soyuz Test Project where the US astronauts actually used it with special programs to perform calculations for the rendezvous.

hmmmmmm.  maybe these gummed up the wheels?

LOL!!! Nah, it's the material they used for the roller surface. The same material was also widely used in tape drives and cassette decks for the capstans. It just turns into mush with age.

[Specmaster]

...find something worth taking a punt on are long gone; the intardnet has made that kind of scrounging nigh-extinct. 

mnem
*sigh*

Says the man who almost literally tripped over two industrial sewing machines on the sidewalk.

Or did he, maybe he snuck them out the backdoor of an old factory somewhere in the frozen north 

[med6753]

All hail Deoxit D5.  This is stuff is great. I had some time to re-visit the Type 3A74 and had easy access to the channel 1 and 2 attenuator switch decks so decided to give it a try. Results speak for themselves, both channels now functional. These switch decks are standard rotary switches, not that gold leaf crap on the later Tek's.

Channels 3 and 4 will be a little tougher to get at.



 

[0culus]

Very nice. Having 4 real traces working will be a handy tool to have on the bench. The only thing better would be a dual beam scope with two dual trace verticals. 

[bd139]

Or a 4 channel DSO 

[Saskia]

bah, going out and just buying a 4 channel DSO, everyone can do that ...

but repairing one of these buggers, that's something completely different.

[bd139]

Buy a broken 4 channel DSO. That’s a larger challenge these days 

[Cerebus]

Of course if one is  going to go to all the trouble of reconditioning a new lathe one might as well bide one's time, pick up a cheap but good old hunk of iron and recondition an old lathe instead.

Köpings mekaniska verkstads AB (Nowadays the Volvo Powertrain gearbox factory) used to cast the beds of their highly regarded lathes, and then put them out in the yard for a year to stress relieve the casting. Only then were they taken in again and machined. Köping lathes still command impressive prices used.  I've got a 1920s Storebro in pieces. Pretty close to a South Bend, actually. Three speeds on flat belt, and back gear. Three-phase 6hp motor.

Presupposing that one has the space to put a 'good old hunk of iron' in, if ya don't you're back to the mini-lathe.

A big lathe can make small parts. The opposite is not always true.

Today, you get to select between Weiler and Trens. Colchester or Köping is no more. Storebro still sell spares at insane prices. In Sweden, also Blomqvist mini lathes were common. But are quite expensive used. Some spares might be available.

Speaking of Colchesters, I saw an imperial Colchester "Student" mark II the other day, for a good price, in good condition (as far as one can judge from photographs), DRO, coolant pump. The price was "jump for it" good. However, if I bought it I wouldn't have a living room anymore - as that's the only space I've got left that's big enough to take it. I also shortly afterward would probably find myself missing my two favourite 'little ball bearings' after the missus found the sofa replaced by over a ton of iron, grease and swarf.

I need a shed, a big shed with a concrete floor and 3 phase...

[tggzzz]

Very nice. Having 4 real traces working will be a handy tool to have on the bench. The only thing better would be a dual beam scope with two dual trace verticals. 

And analogue storage.
 
My local backspace has a telequipment dm63, dual beam three channel analogue storage.

It works too, except for a 100Hz brightness variation. I wonder what could possibly cause that