Test Equipment Anonymous (TEA) group therapy thread

[grizewald]

...First bit of Test equipment I have bought to restore...

Welcome to the addiction Randall. 

[beanflying]

Welcome to the Mad House  Also add them over here along with my Bomb proof version and other Knobs and Feet https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2267436/#msg2267436

I also destructively tested one of the Prototypes 

[grizewald]

Score!!





While it's nowhere near as pretty as bd's little 'scope, I think it has a '70s charm all of its own. Putting the B channel to the left of the A channel is suitably odd. I'd never even heard of Scopex despite being born not so far from Letchworth, so it's also got a bit of sentimental appeal there.


I just hope and pray that the seller complies with my request to remove the UK plug before shipping. Combining anything even remotely fragile with an equipment smashing mace is always a bad idea!

[Specmaster]

Whoops. I think these work in them. I'm sure I used them on something heathkit a few years back: https://www.rapidonline.com/truconnect-4mm-binding-posts-83061

Yeah, those would work OK, but TBH at the moment I CBA, I'll wait till I can make up an order for postage paid status. Theres nothing actually wrong with the existing ones apart being slightly faded, and those on the TS3021S are faded but perfectly OK and looking at its constructed it is going to a PITA to get at them just for vanity’s sake. Even then I bet they take a different size or are of a keyed variety, so they can stay for now at least 

[Specmaster]

Score!!





While it's nowhere near as pretty as bd's little 'scope, I think it has a '70s charm all of its own. Putting the B channel to the left of the A channel is suitably odd. I'd never even heard of Scopex despite being born not so far from Letchworth, so it's also got a bit of sentimental appeal there.


I just hope and pray that the seller complies with my request to remove the UK plug before shipping. Combining anything even remotely fragile with an equipment smashing mace is always a bad idea!

I think that is just as nice, its neat and tidy and has the oddity of B before A channels, sweet.

[grizewald]

I think that is just as nice, its neat and tidy and has the oddity of B before A channels, sweet.

It is a bit

It also looks clean, so even if it needs some attention, I won't have to clean years of mostly human grime off it. I don't mind cleaning test equipment, but some stuff is pretty gross - like the keyboard of someone who doesn't wash their hands.

[grizewald]

It turns out that the Scopex 14D-10 was actually announced in 1981 (clipping from "Studio Sound" magazine, May 1981)

[BU508A]

Today the PCBs from Osh-Park arrived. In deep purple. 

Aren't they kind of beautiful? 



I assembled one for my PM6681.

Top side. Have ordered the wrong electrolytic capacitors    SMD instead of through-hole ones.
But with some file working they fitted nicely. 



Bottom side, had some 0603 to solder but it was an easy job.



And this is the output of the OCXO. The sine is looking a bit spikey but I think this is due to my not so good ground connection from my scope probe (cable was too long):



Next step is getting an Efratom Rubidium 10MHz frequency standard to calibrate this little OCXO and put it into the PM6681.

Edit:
Forgot to mention some specs:
I've connected the OCXO to my PSU @ 24V. If you switch it on it draws around 150mA at the first moment. After a while the current is stabilizing at around 55mA.

Edit 2:
Link to Dan's website. He was so kind to upload and share the PCBs to Osh-Park. Thanks!
https://syncchannel.blogspot.com/2016/04/flukephilips-pm66xx-frequency-counter.html

Will keep you updated ...

[mnementh]

@BU508A:
I've done a number of small runs through OSHPark; have had nothing but good luck and excellent quality product. Folks tell me they're too expensive, but I never paid more than $30 for an order, and most much less. I usually find myself doing more than the one thing I really need just to make a complete order for free shipping.
Also, I'm a sucker for Royal Purple, so yeah. 

In Other News...



Now I have my bits & pieces together to sort the PCIe power situation, I just wanted to vent a little on the fit & finish of this $1000+ GPU. You'd think for that kind of money, they could have assembled something a little more finished looking than this Steaming Pile of JANK for the fan wiring, FFS. 

Everything about the Aorus MB is so nicely fit & finished; even the locations & mount angle of the sockets & jacks are laid out to facilitate a nice tidy build, unlike some brands *coughMSI & ASROCKcough* who seem to only care about easiest & cheapest BOM. 

And of course, none of THIS butt-uglee is shown on the adverts for the WaterForce 2080 Super-Jank; I seriously considered sending it back for all of about 3 seconds. 

Having that fugly mess right up in my PC's picture window, now I really don't care that my PCIe cables won't match... instead of making a pair at once like I planned, I think I'm gonna just make the one cable I need and get it running until we our immigration goes through and I have my bench whole again. 

mnem

[WastelandTek]

whelp

Got the last of the parts for an HP 200-CD restoration I am working on here.  It came up beautifully, super clean signal.  I was going through the calibration procedure and it was coming right into line, very nice, then I was ever so carefully tipping the chassis over to get at the other adjustments, like seriously, really carefully, and pop...my brand new 5AR4 rectifier split its envelope...

Done for tonight...

[Carl_Smith]

Since my ISP is a cable TV company they keep trying to get me to sign up for free 200 down if I get the 3 way package of TV, phone, internet for $99 plus tax for one year. After the one year watch out and take out a mortgage.

I dumped their TV service a year ago because of their ridiculous prices. I don't want nor need a house phone. So they can stick it. 

Did the same over a decade ago; never looked back. I refuse to have commercial broadcast of any sort in my home; it's full of children who need to grow up knowing it isn't normal to be bludgeoned with advertising every 10 fucking minutes.

mnem
The adults can go shit up a crooked stick, however.

If you take "normal" to mean typical or standard then it is normal.  Not that it should be.

Reminds me of a podcast where someone was talking about how they limited their children's TV watching to almost nothing, and when they did see some TV they didn't have any "immunity" to the ads and everything advertised was "Dad! We need one of those!"   

Of course there's the applicable Futurama scene:
https://comb.io/WZXXFi

[beanflying]

Put my head into the Shack to look at a 3D print. 45C over the bench so I am retreating to the relative cool of the house to seek out a Beer and a cool corner.... 

[worsthorse]

Yes, it was too good a deal to pass up. I am picking it up on Friday. I will have a chance to test it, too, so if the diagnostic failure is really the only self-test fail and that turns out to be caps, as it often seems to be with this scope, it will be a bargain.

And if I can't fix the busted channel and the others are still good, well it is still a pretty good deal.

[med6753]

whelp

Got the last of the parts for an HP 200-CD restoration I am working on here.  It came up beautifully, super clean signal.  I was going through the calibration procedure and it was coming right into line, very nice, then I was ever so carefully tipping the chassis over to get at the other adjustments, like seriously, really carefully, and pop...my brand new 5AR4 rectifier split its envelope...

Done for tonight...

Was it a physical shock or simply turning over the chassis caused it to split? You have to be careful with rectifier tubes when in operation and their orientation. Directly heated rectifiers such as the 5U4 are especially sensitive to this. If the tube is on it's side while in operation the filaments can sag and short to the plate. There are specific warnings in the RCA Receiving Tube Manual regarding this. Vertical mount preferred unless mounted with the socket in a specific plane. Now the 5AR4 is an indirectly heated rectifier and the manual doesn't specifically recommend vertical mounting but I think it would be wise to do so.     

[WastelandTek]

Good for you worsthorse.  I am envious.

Yeah med, no shock, just tipping...$20 lesson, I won't be doing that again with it lit.

[worsthorse]

Last time I was at the bench I was working on the DM502.  Went through the manual's calibration and test procedure and all was fine until I got to the current measurement tests. They were all wrong but sort of randomly so. The data didn't make sense, so I figured I was doing something wrong and stopped for the night. Then my back injury flared up, keeping me from the bench for a week. 

The 502 is a simple instrument. There's one signal path with different front end sections for AC, DC, and resistance measurement, including separate attenuators for current and voltage. I thought maybe the attenuator was damaged, so I checked both. Not the problem.  The path on the other side of the attenuators seemed to be working fine, too. Puzzling.

Turns out the problem was with my current generator setup and how it interacted with the DM502. I don't have a proper current calibrator, so I figured I would use my precision voltage source to make one.  Set it up, put my 8840A in line,  adjust the current, take the 8840A out and put the DM502 in its place.

Problem one:  the DVC8500 doesn't do a good imitation of a current source. Problem two: the DM502 current meter resistance is range dependent and varies from 0.1 to 2000 ohms. So the effect of the DM502 resistance in my circuit varied a lot and was quite significant in the low current ranges.    I made some changes to my "current source" setup to take this into account and the current measurements starting making sense. PEBMAD problem solved. 

I still need to figure out how to cobble together a AC current source. No good ideas yet, at least with the equipment I have at hand. So that function and the decibel conversion circuit will be checked tomorrow. After that's done, I will start on one of the three units that definitely isn't working.

[beanflying]

It's a 'pleasant' 40.5C in the shack at present so time to play with some TEA 

Thought I might as well complete a set of elevated Temperature data on the AD584 Vref. That enough self abuse and my 3D print has just finally unstuck after 15 minutes in the Fridge to get the glass down in Temp

[McBryce]

I've seen that, however the supplier I was referring to is Reichelt. I suppose it's just one more reason not to use Reichelt any more as they have been steadily going down hill for several years now anyway.

McBryce.

Ah, I suspected that you've meant Reichelt but wasn't 100% sure. I saw that Reichelt has kicked out all leaded solder and I will stock this year lots of my most-liked solder, that's for sure.
But I'm not sure what you are meaning regarding Reichelt is going more and more down-hill over the past years. Have you any examples or stories you'd like to share with us?

Their delivery times, packaging , etc are all fine, but their component selection seems to be getting narrower while their prices are going up. I used to be able to order everything from one place, where I now find myself having to go somewhere else for parts to compensate for what they either don'T have in stock or offer at all.

Last night I stocked up via ebay. 1.5kg (3 x 500g) in my three preferred sizes and all for less than I would have paid elsewhere. However, I went for Stannol this time although I normally use Felder.

McBryce.

[Martin.M]

the moste cute mini scopes ever are british COSSOR

Did my work experience at Cossor

The mini oldies of them, with the little knobs, that is grandmaster design.
there is a blog in the web where u find some of them, was it richard sears?

[bd139]

I think Richard sears did some restorations although not sure where. There is also http://cossor.co.uk/ which is radio only and kind of funny because I used to have an email address on that domain (worked for them for a bit after uni as well)

[tggzzz]

Since my ISP is a cable TV company they keep trying to get me to sign up for free 200 down if I get the 3 way package of TV, phone, internet for $99 plus tax for one year. After the one year watch out and take out a mortgage.

I dumped their TV service a year ago because of their ridiculous prices. I don't want nor need a house phone. So they can stick it. 

Did the same over a decade ago; never looked back. I refuse to have commercial broadcast of any sort in my home; it's full of children who need to grow up knowing it isn't normal to be bludgeoned with advertising every 10 fucking minutes.

mnem
The adults can go shit up a crooked stick, however.

I was once on a business trip with a colleague, a lovely guy (from Ft Collins CO) even though he was reading the Bible He didn't have TV for his kids because he didn't want them seeing the nasty stuff on the news.

I mentioned that I preferred to see and discuss the news with kids. One way or another they are going to find out that not everybody is nice and that there are situations they should be aware of and try to avoid. I prefer that they find this out under controlled circumstances, not by other mechanisms blundered into after they leave home.

To his credit, my colleague did get a TV a couple of months later.

[bd139]

Sounds like my grandfather and the radio. My grandmother signed up for a Rediffusion rental when he was out one day 

[Specmaster]

@BU508A:
I've done a number of small runs through OSHPark; have had nothing but good luck and excellent quality product. Folks tell me they're too expensive, but I never paid more than $30 for an order, and most much less. I usually find myself doing more than the one thing I really need just to make a complete order for free shipping.
Also, I'm a sucker for Royal Purple, so yeah. 

In Other News...



Now I have my bits & pieces together to sort the PCIe power situation, I just wanted to vent a little on the fit & finish of this $1000+ GPU. You'd think for that kind of money, they could have assembled something a little more finished looking than this Steaming Pile of JANK for the fan wiring, FFS. 

Everything about the Aorus MB is so nicely fit & finished; even the locations & mount angle of the sockets & jacks are laid out to facilitate a nice tidy build, unlike some brands *coughMSI & ASROCKcough* who seem to only care about easiest & cheapest BOM. 

And of course, none of THIS butt-uglee is shown on the adverts for the WaterForce 2080 Super-Jank; I seriously considered sending it back for all of about 3 seconds. 

Having that fugly mess right up in my PC's picture window, now I really don't care that my PCIe cables won't match... instead of making a pair at once like I planned, I think I'm gonna just make the one cable I need and get it running until we our immigration goes through and I have my bench whole again. 

mnem

I never quite got all this business about caring so much about what the insides look like, for me as long as its tidy, I'm happy. Surely its more about how it performs? I dont sit and stare at my PC through its picture window side, I sit and look at the screen. Shove the computer box under the bench and free up some more valuable real estate for work space FFS   

What happens then if your immigration doesn't come through, back to the butt ugly big suck again??

[McBryce]

Here's the mini-oldies I own (these are not my actual devices, just pictures from the Interwebs):
A Voltcraft 1532 and a Russian CI-94. Both work fine, but for obvious reasons, they are just decoration now and never get used.

McBryce.

[mansaxel]

Putting the B channel to the left of the A channel is suitably odd.

What with driving on the other side of the road, pulling faders DOWN to increase gain, having "4" on a meter scale indicate 0dB, enumerating mixing desk channels right to left, and rage-quitting the most prosperous loose federation of countries on the earth, having "B" left of "A" is just keeping in style of consistent back-asswards behaviour.

 

And don't get me started about the habit of measuring people in "stone".