Test Equipment Anonymous (TEA) group therapy thread

[Robert763]

I still have the No-Volts and all fire current test boxes I made up for Thrust SSC. I designed the firing circuit for both the parachute squibs and the initiator for the Martin Baker ejector seat rocket motor mounted in the nose. Never had an unintended discharge.

[Vince]

[HP 120B tubes]

Hmmm... looks like neither the 6DJ8 nor the 6AU6 are drop-in replacements for the 6U8 !  Grrrr Tek.

Downloaded datasheet for the 3 of them. 6U8 is a pentode + triode.  6AU6 is just a pentode, no triode in it. As for the 6DJ8, it's a double triode, no pentode.
Plus, the pinout is different anyway.

So no choice, I must BUY these bloody 6U8, three of them. 

Just had a look on evil bay. Cheapest in Europe is 5 Euros + 2 Euros shipping for a single one, UNtested, just cross your fingers basically, but the guy pretends they come from the "good" stock of an ex professional. So they are likely to be good, but untested so no promises made. At least the guy is honest. So that would be 21 Euros this way :

https://www.ebay.fr/itm/323217546368



OR, I found ads for a Russian equivalent tube, sold by a guy in Ukraine. dirt cheap, pack of 12 or 16 of them for 4 Euros, plus 8,8 Euros for shipping, so 12,8 Euros, almost half the price.

https://www.ebay.fr/itm/264170956927

Ukraine is not part of Europe so if I am unlucky I will have to pay import taxes on the stuff. But  even if I do, should be negligible : 20% VAT on 4 Euros is 80 cents, + eventually add a percentage for importation, but again no matter what that percentage is, it won't amount to much anyway.

So for 12 Euros it's worth trying to trust the Russian.... maybe they are actually equivalent to a 6U8, maybe the scope won't catch fire if I use these tubes, and maybe out of 16 tubes, I will find 3 tubes that actually work. I only need 3....


Found the problem in my tube spreadsheet : I did not goof anything... my mistake was to trust the service manual when putting together the list of tubes that my scopes were SUPPOSED to contain...
Parts list shows 11 tubes that got substituted starting from SN 4804. My two 515A are SN # 100719 and 100800. Leading digit being the plant code, SN are therefore 719 and 800... so supposed to be BEFORE the change point. "Supposed" to, supposed........ just.... " supposed "... hmmm..... Tek Tek Tek Tek... 

Just updated my spreadsheet accordingly, hoping it's good now...

[Saskia]

I still have the No-Volts and all fire current test boxes I made up for Thrust SSC. I designed the firing circuit for both the parachute squibs and the initiator for the Martin Baker ejector seat rocket motor mounted in the nose. Never had an unintended discharge.

just make sure you get rid of the canopy before the ejector seat fires ...

[Robert763]

It wasn't under the seat. It was in the nose beween the two engine intakes and pointing UP. The problem is that if the nose started to lift it would be too fast to do anything about it. Solution was the rocket motor. If the nose of the car started to lift, the rocket motor would fire keeping the nose down for about a second. This was long enough for the hydralics to lift the tail and the engine shut  offs to operate. Raising the tail moved the center of pressure forward and increased  drag. The engine thrust lines were half a degree UP so reducing power also increased down force.

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

[Cerebus]

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

You might be surprised, should you ever have the opportunity to examine the phenomenon first-hand, how much time you have to think, and what you think about when the excrement hits the air moving device at high speed.

I've been involved in two high speed road traffic 'incidents' and both times my perception of time slowed so much I actually had time to consider and make rational choices about how to cope with the situation while enjoying Newtonian mechanics first hand. Time in the immediate aftermath of something like that seems to slow by a factor of 10 or so, so someone who gets to see Martin-Baker's finest in action might well have time to ponder what had just happened, also appreciate the fireworks display, and plan what to do next once the ability of limbs to move catches up with the speed that thought is currently flying by at.

[SilverSolder]

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

You might be surprised, should you ever have the opportunity to examine the phenomenon first-hand, how much time you have to think, and what you think about when the excrement hits the air moving device at high speed.

I've been involved in two high speed road traffic 'incidents' and both times my perception of time slowed so much I actually had time to consider and make rational choices about how to cope with the situation while enjoying Newtonian mechanics first hand. Time in the immediate aftermath of something like that seems to slow by a factor of 10 or so, so someone who gets to see Martin-Baker's finest in action might well have time to ponder what had just happened, also appreciate the fireworks display, and plan what to do next once the ability of limbs to move catches up with the speed that thought is currently flying by at.

I had that happen in a motorcycle accident once.  A honking big Kawasaki z1000 weighing nearly 500lbs, not a great handling machine on the best of days but crazy fast.  A van turned out on the road in front of me, I was going 70mph and there was nothing I could do...   

Time almost stopped.   I had time to plan everything - how I would flip the bike off the road over the quite high kerb, landing on its side, missing the van...   how the bike then had to slide along the ground through a narrow gap between a tree and a road sign,  into a narrow strip of land that would act as a "landing strip" - while avoiding hitting the brick wall at the end...  I figured out how I had to clutch on to the bike with my knees and thighs, keeping my arms and shoulders tight and straight, letting the motorcycle take the brunt of the friction forces, avoiding sticking any limbs out while the mayhem was going on...

Each step of the plan was executed in what subjectively seemed a veery long time: missing the van and high-siding the bike as planned, falling on its side, missing the tree, missing the road sign, and finally grinding to a halt after several rotations on the narrow strip...  Soil, grass, and stones were spraying everywhere.  Never have I been so grateful for "sissy bars".  As the dust settled, I was still gripping the bike, "sitting" on it as if it was still upright, no part of my body touching the ground.  I got off the bike and stood up.  Not a scratch... the only damage was my pant pocket which got torn off (no skin contact).    The bike was bent out of shape and minus mirrors, turn signals, etc., on the "down" facing side...  but still just about rideable after pulling the handlebar straight again. 

OMG that was one heck of a motorcycle lesson for me, LOL! 

[mnementh]

It wasn't under the seat. It was in the nose beween the two engine intakes and pointing UP. The problem is that if the nose started to lift it would be too fast to do anything about it. Solution was the rocket motor. If the nose of the car started to lift, the rocket motor would fire keeping the nose down for about a second. This was long enough for the hydralics to lift the tail and the engine shut  offs to operate. Raising the tail moved the center of pressure forward and increased  drag. The engine thrust lines were half a degree UP so reducing power also increased down force.

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

It's like the Blue Flame got pregnant. And FASTER. 

mnem

[mindcrime]

It's just a distribution amplifier... not even real test equipment. I said, it's just a bloody distribution amplifier! IT DOESN"T COUNT OK!??? I aM nOT An ADDicTT. I kan St0p Anytim3. It's just an amplifier, just an amplifier, just an amplif...





...ier. Doesn't count. Doesn't count. Not an addict. Not an addict............

[cyclin_al]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

I know. These damn Engineers. Bunch of stuck ups. 

At least we don't have to wear their uniform. 

Heyyyyy !!!!! I are an engineer 

[cyclin_al]

moo.

Looking for my big red box of o-rings, that I might mod these RC cars with oil-damped shocks. grr.

mnem
and I'll probably use my cheap0 Chinese calipers to measure 'em.

When fixing up the well after the fracking expert a few weeks back, my engineer buddy strongly suggested I get the big red box of o-rings from Princess Auto.

What size do you need?  If that kit from Princess Auto has the size you need, then that gives me a second reason to pick one up...

[Saskia]

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

You might be surprised, should you ever have the opportunity to examine the phenomenon first-hand, how much time you have to think, and what you think about when the excrement hits the air moving device at high speed.

I've been involved in two high speed road traffic 'incidents' and both times my perception of time slowed so much I actually had time to consider and make rational choices about how to cope with the situation while enjoying Newtonian mechanics first hand. Time in the immediate aftermath of something like that seems to slow by a factor of 10 or so, so someone who gets to see Martin-Baker's finest in action might well have time to ponder what had just happened, also appreciate the fireworks display, and plan what to do next once the ability of limbs to move catches up with the speed that thought is currently flying by at.

I had that happen in a motorcycle accident once.  A honking big Kawasaki z1000 weighing nearly 500lbs, not a great handling machine on the best of days but crazy fast.  A van turned out on the road in front of me, I was going 70mph and there was nothing I could do...   

Time almost stopped.   I had time to plan everything - how I would flip the bike off the road over the quite high kerb, landing on its side, missing the van...   how the bike then had to slide along the ground through a narrow gap between a tree and a road sign,  into a narrow strip of land that would act as a "landing strip" - while avoiding hitting the brick wall at the end...  I figured out how I had to clutch on to the bike with my knees and thighs, keeping my arms and shoulders tight and straight, letting the motorcycle take the brunt of the friction forces, avoiding sticking any limbs out while the mayhem was going on...

Each step of the plan was executed in what subjectively seemed a veery long time: missing the van and high-siding the bike as planned, falling on its side, missing the tree, missing the road sign, and finally grinding to a halt after several rotations on the narrow strip...  Soil, grass, and stones were spraying everywhere.  Never have I been so grateful for "sissy bars".  As the dust settled, I was still gripping the bike, "sitting" on it as if it was still upright, no part of my body touching the ground.  I got off the bike and stood up.  Not a scratch... the only damage was my pant pocket which got torn off (no skin contact).    The bike was bent out of shape and minus mirrors, turn signals, etc., on the "down" facing side...  but still just about rideable after pulling the handlebar straight again. 

OMG that was one heck of a motorcycle lesson for me, LOL! 

Similar experience in my car when the rear wheels decided to overtake the front wheels at 240 kph. I did several 180s or so while trying to get it back under control and managed to do so. On the way back home I managed to have an average fuel consumption of less than 10l/100. On a supercharged Jag XKR ...
Did not even bend any metal...

[Robert763]

[beanflying]

Not buying it but interesting mixup of styles including Nixies  eBay auction: #324648073938

[xrunner]

I finally got the Agilent E4411B spectrum analyzer flash memory and firmware upgraded after a little pain. If you're interested you can dive into it at this point -

https://www.eevblog.com/forum/repair/agilent-esa-e4401b-memory-(b72)-and-firmware-upgrade/msg3577246/#msg3577246

[mnementh]

moo.

Looking for my big red box of o-rings, that I might mod these RC cars with oil-damped shocks. grr.

mnem
and I'll probably use my cheap0 Chinese calipers to measure 'em.

When fixing up the well after the fracking expert a few weeks back, my engineer buddy strongly suggested I get the big red box of o-rings from Princess Auto.

What size do you need?  If that kit from Princess Auto has the size you need, then that gives me a second reason to pick one up...

I have the big red kit from Princess Auto. What's steaming my ol' tail-scales is that I can't lay paws on it.  Or the little kit I bought before that one.  And Ifni save me, I ordered another at 3am out of frustration, as they have it half price in the Surplus Dept; all of $12 right now.

I still need to glom up some pretty heavy oil for these; according to the vids, they need like 800cst to be at all effective. I know I have some 1000cst here somewhere too; but I'll probably wind up buying that as well. I may try a little Vaseline from the medicine cabinet first tho.

I think it's probably Murphy or one of her puppies making a example of me for daring to bitch aboot the way tape measures only exist part-time in the prime material plane.   

In answer to your question, the one we always need is A0005 3/32 ID; also 2mm ID x 1-1.5mm cross-section will work as well. The upper cap needs ~9mm ID x 1mm cross-section, according to the vids. And you're gonna need 'em for yours; there's 8 of each for 2 vehicles, and when you need to rebuild after they get worn and leaky, that'll use up all there are in the kit.

mnem
 It's kinda like deja vu'... kinda like deja vu'...

[Cerebus]

OMG that was one heck of a motorcycle lesson for me, LOL! 

It will come as no surprise that both my experiences happened on Motorcycles, one as a pillion passenger on a Honda 400-4 "plastic pig" at circa 80 mph, and one as rider on a Suzuki X7. The latter when some dipshit Volvo driver pulled out and just stopped sideways on about 15 feet in front of me travelling at 40 mph with headlight on and a high-vis jacket in broad daylight (so 1/4 of a second away). Not a scratch on my lily white body either time, one bruise the second time, all down to having subjective time to think "OK, this is what I'll do".

If I could figure out how to consciously turn on that mental "time dilation" effect I could make a fortune.

[Saskia]

Not so lucky when I got run over by a VW Tuareg. The fucking cunt told the police he was not to blame as I did not get out of his way fast enuff so he ran me over.
Management Consultant, what do you expect.

4 years paralysis of my left arm because of that cunt.
May Thor smite him with mighty Mjölnir.

[Saskia]

picked up a Space Invaders Arcade1up for reasonable funds.

[mnementh]

Picking up the saw and some scrap ply to make some ramps and goals so we can play Rocket League IRL. 

mnem
brrrrrowwwwrrrrr!!!

[Ice-Tea]

Well, I experience "slow time" in a car crash too once.

Drove a Citroen Saxo (1.5d). Highway, had been raining a bit, 120kph. Drove along happily, all of a sudden control was just.. gone. Still don't know what happened. Pothole? Debris? Tree branch? Started spinning. Dragged the nose across the mid-road barrier. Sparkles, pirotechnics (airbag, I would guess). All very entertaining when time is slow. I was pretty sure my goose was cooked. Stopped hugging the barrier and though "well, this ain't so bad" after which the barrier on the other side came into view. None of that sliding, kissing, skidding barriers. Close to frontal, this one. Plenty of time for some choice swear words (in my mind at least). The bang was epic, but not as bad as it could have been as I had lost a lot of speed by then.

The cabin was filled with smoke, so I started grabbling for the fire extinguisher. Was only the smoke from the airbag. Turned down the windows, that still worked. Was pretty much off the planet, and for some reason wanted some music. The CD player simply worked. It played, I kid you not, "Road to Hell" by Chris Rea. Cops showed up pretty fast after that.

Side story: at that time my mate was putting together a skitrip with friends. While I was waiting for my dad to pick me up (my body was pretty much just a chain of bruises), he called to confirm if I was still joining. I said "sure" in what I was thinking was a conversational tone. I met my wife on that trip. If I had chickened out, I never would have.

[med6753]

Interesting stories of near death and time slowing down experiences. I guess I've been very lucky. I don't recall having it happen to me.

Anyway, started PSU recap of the "keeper" Type 454. First up is the regulator board. Here it is complete. C1195, the 3uf/150V tant was original. For those interested the markings on the cap were "109D" and "6930". I replaced it with a 10uf/160V aluminum.



Installed the regulator board and verified the voltages before moving on. All is well.



Tomorrow's project is to start on these cans. Getting to them is going to be a real treat.



In order to get at the cans this A Sweep board has to come out. Now it looks like a complete nightmare but it is all modular. And the manual has excellent pictorials. Plus I'll be taking a lot of pictures. And I have the other 454 to refer to if needed.

 

And speaking of the other Type 454. I worked on it yesterday with the intention of getting it calibrated to sell and it's a piece of shit and will definitely be a parts unit. Due to prior Gorilla handling both variable volts/div assemblies are damaged beyond repair. And channel 1 has multiple high frequency issues that I just can't be bothered with. 

[Saskia]

completed some vintage stuff.

[bsfeechannel]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And a hard hat.

[tautech]

a Suzuki X7.

A model you don't hear much about these days as the Yamaha LC's stole their thunder back in them days.
Brought a new late model X7 ~late '81 IIRC, black with mags and it looked a pretty picture when it was clean  but only had it for a short while as I got married and went back to pops farm where it wasn't much good in the mud ! 
Still, the X7 hold the record of the first mass produced production bike capable of 100mph which was pretty good for a carbed aircooled 250cc twin but like any small capacity Jap motor you needed to fully wind the rubber band for it to perform. 
Only came off it once @~10mph after hitting the only 2" rock on a gravel road 90^o corner that I'd spotted 100yds away and still didn't miss it ! 
Only injury was to ones pride. 

[25 CPS]

completed some vintage stuff.

That’s a fine looking B77!