Test Equipment Anonymous (TEA) group therapy thread

[mansaxel]

Mine is the same one with the options, but I'm getting strange output level unless I'm reading the adjustment section of the manual wrong... I don't have the manual on me now, but IIRC it was low output with the two 300ohm resistors connected, but within spec with them disconnected. The manual reads a bit weird though, it takes me reading each step a few times to work out exactly what they are trying to explain to do.
Everything else seems fine so far though.

I bought the parts to make the RC normalizer for the AM502 today, so I'll have another go at it soon.

Mine puts out level just right into a 600@ termination, measured across a number of meters.  I think we agree that that is what is desired.

Regarding TM500 contents,  I've come up with a Heath Robinson consisting of a FeelTech FY3200 function generator, an USB cable, a Perl Script, and for demonstration purposes, a Heavy Duty Avometer.    This allows me to set levels on the FY3200 and iterate around them, so that I can exercise the reed relays of the AA501A. I'll try to get it on video for a laugh.

[Vince]

Another Tektronix video monitor just popped up here. As often only 50 Euros, but looks alive and more modern that the ones I usually see for sale. So might be a good deal...

For whoever was interested in that the other day ?

https://www.leboncoin.fr/equipements_industriels/2099475645.htm

[Cerebus]

I think diesel engines are preferable in winter conditions because of their increased weight and grip as a result of the weight, but also because of their low down pure grunt.

Eh? In another post you advocate selecting 2nd gear to pull away in snow - something that will reduce available torque - and now you're advocating a higher torque engine for winter conditions. You can't have it both ways.

Also the weight argument doesn't cut the mustard. Yes, more weight means more grip, but the momentum/inertia associated with that mass will increase in exact proportion, cancelling out the extra grip which also increases in exact proportion to mass.

[tautech]

Snow, ice.....try driving a fully laden 2 axle tipper on wet green grassed hill country if you really want a thrill.
Even independent rear wheel brakes were essential but could also get you in the poo if you weren't careful with them.

[mnementh]

Just finished to watch "don't look up" movie.
Excellent.

Is that the title of the movie, or an instruction implying that you'll pollute your search history forever if you do look it up? 

No, that was "Donna Hooks Up!"   

mnem
"Asking only workman's wages, I come looking for a job...
But I get no offers;
Just a come-on from the whores on Seventh Avenue.
I do declare, there were times when I was so lonesome
that I took some comfort there..."   ~The Boxer - Paul Simon

[Specmaster]

I think diesel engines are preferable in winter conditions because of their increased weight and grip as a result of the weight, but also because of their low down pure grunt.

Eh? In another post you advocate selecting 2nd gear to pull away in snow - something that will reduce available torque - and now you're advocating a higher torque engine for winter conditions. You can't have it both ways.

Also the weight argument doesn't cut the mustard. Yes, more weight means more grip, but the momentum/inertia associated with that mass will increase in exact proportion, cancelling out the extra grip which also increases in exact proportion to mass.

Yes, diesel engines in 2nd gear, engine idling and letting the clutch does in fact reduce the torque at the wheel, whereas a petrol or gas engine will more than likely stall unless revs are applied in which case wheel speed increases and slip is more likely. With most modern cars, they are front-wheel drive and the more grip you have, the better. Add a diesel engine into that mix and the extra weight over the driven wheels does infact equate to better grip.

Believe me, it works, I've driven all kinds of cars, front, rear and AWD drive trains and if AWD is not an option then diesel, front is the next best thing.

Another advantage with diesel is because of the increased torque at lower RPM, you can very often, as was the case with the buses I mentioned, once you get rolling, change up and leave the engine at idle and the bus pull very nicely and gather sufficient speed to keep you moving at a reasonable and safe speed for the conditions and by using the gearbox, minimise the use of brakes. That is when weight is against you and there is a far greater chance of the wheels losing grip and skidding.

[Specmaster]

Snow, ice.....try driving a fully laden 2 axle tipper on wet green grassed hill country if you really want a thrill.
Even independent rear wheel brakes were essential but could also get you in the poo if you weren't careful with them.

True, you have weight and gravity working against you there, and once you get wheel spin, the grass and mud just become a shiney skid patch.

[mnementh]

So, to calibrate and adjust the SG505 Oscillator, I need to restore and adjust and calibrate an AM502 differential amplifier, and to do that I need to build an RC normalizer.

I built one before so it's no big deal to build another, but can someone tell me where the rabbithole ends???     

This rabbit hole is the shape of a Klein bottle. Hope that helps.  https://en.wikipedia.org/wiki/Klein_bottle

I need to build a coffeepot using this technology. 

mnem

[Peter_O]

I once passed a street crossing where a tank truck slowly comes to a halt, finally on the ice in front of the traffic light. There the whole truck starts skidding half a meter back an forth with standing wheels as the contents sloshes inside the tank. Didn't want to be in place of the driver. 

[tautech]

Snow, ice.....try driving a fully laden 2 axle tipper on wet green grassed hill country if you really want a thrill.
Even independent rear wheel brakes were essential but could also get you in the poo if you weren't careful with them.

True, you have weight and gravity working against you there, and once you get wheel spin, the grass and mud just become a shiney skid patch.

We used all kinds of tricks like specialized directional treads and partly raised tips to get to where we needed to and most interesting was silage time where the truck (a 381ci 123hp Bedford TK 10sp) had to match harvester tractor speed regardless of terrain or load.
It led to very interesting discussions between pop and I. 
Although I'd done a good deal more truck driving than him and our kiddies wanted to come along for the ride it was better that they didn't hear me cursing at him so I sucked it up and drove the tractor and he had the kids in the truck. Never was told by the kids what he said about my driving. 
Gawd I miss them days of some 30+ years ago and the old fella too. 

[Specmaster]

I once passed a street crossing where a tank truck slowly comes to a halt, finally on the ice in front of the traffic light. There the whole truck starts skidding half a meter back an forth with standing wheels as the contents sloshes inside the tank. Didn't want to be in place of the driver. 

Sounds very much like a defective tank, they are supposed to have loads of baffle plates with holes in them to minimise the effect of the load shifting.

[Peter_O]

I once passed a street crossing where a tank truck slowly comes to a halt, finally on the ice in front of the traffic light. There the whole truck starts skidding half a meter back an forth with standing wheels as the contents sloshes inside the tank. Didn't want to be in place of the driver. 

Sounds very much like a defective tank, they are supposed to have loads of baffle plates with holes in them to minimise the effect of the load shifting.

Yea. I should have added, that it happened some 30 years back in history. 

[Cerebus]

I think diesel engines are preferable in winter conditions because of their increased weight and grip as a result of the weight, but also because of their low down pure grunt.

Eh? In another post you advocate selecting 2nd gear to pull away in snow - something that will reduce available torque - and now you're advocating a higher torque engine for winter conditions. You can't have it both ways.

Also the weight argument doesn't cut the mustard. Yes, more weight means more grip, but the momentum/inertia associated with that mass will increase in exact proportion, cancelling out the extra grip which also increases in exact proportion to mass.

Yes, diesel engines in 2nd gear, engine idling and letting the clutch does in fact reduce the torque at the wheel, whereas a petrol or gas engine will more than likely stall unless revs are applied in which case wheel speed increases and slip is more likely. With most modern cars, they are front-wheel drive and the more grip you have, the better. Add a diesel engine into that mix and the extra weight over the driven wheels does infact equate to better grip.

Believe me, it works, I've driven all kinds of cars, front, rear and AWD drive trains and if AWD is not an option then diesel, front is the next best thing.

Torque is torque, it doesn't know whether it's petrol torque or diesel torque. The torque doesn't care if it passed through a slipping clutch or not, each Nm is still just a Nm. An engine will only stall if there is enough grip to provide the necessary opposing force, in which case you were in the wrong gear for the conditions. If you can't pull away in second then you've got enough grip to not have needed to try to pull away in second. There's no subtlety here, this is basic Newtonian mechanics that we all learned when we were 13.

Another advantage with diesel is because of the increased torque at lower RPM, you can very often, as was the case with the buses I mentioned, once you get rolling, change up and leave the engine at idle and the bus pull very nicely and gather sufficient speed to keep you moving at a reasonable and safe speed for the conditions and by using the gearbox, minimise the use of brakes. That is when weight is against you and there is a far greater chance of the wheels losing grip and skidding.

That is still about progressiveness of control and nothing to do with weight, or fuel type. If you're at idle and have got to change gear to add engine braking (rather than just lifting your foot off the accelerator pedal) and you are relying on engine braking then you're in less control than you would be if you selected a higher gear and maintained control with the accelerator pedal. The advanced driving instructors that I used to know (police Sgt. Saunders and his daughter Annette "Fish" Saunders, Annette gave me my advanced motorcycle training) would both give you a proper dressing down for driving like that. I think you're trying to say "In slippery conditions, select a higher gear than you normally would and make use of anticipation and gentle progressive engine braking, rather than inattention and late, harsh braking" - at least I hope you are. In that case the extra torque of a diesel engine at lower revs is neither here nor there because you're trying to minimise the effective available engine braking torque, not maximise it.

[BU508A]

So, to calibrate and adjust the SG505 Oscillator, I need to restore and adjust and calibrate an AM502 differential amplifier, and to do that I need to build an RC normalizer.

I built one before so it's no big deal to build another, but can someone tell me where the rabbithole ends???     

This rabbit hole is the shape of a Klein bottle. Hope that helps.  https://en.wikipedia.org/wiki/Klein_bottle

I need to build a cofeepot using this technology. 

mnem

Some years ago I went to one of those medival markets, which are popular here.
I spotted there a glassblower and asked him, if he could build me a Klein bottle (Kleinsche Flasche).
He asked me back: "A little bottle? (Eine kleine Flasche?)" and I replied: "No. A Klein bottle."
He: "Well, if you bring me a picture, I'll try."
Me: "Okay. " 

Next day I've brought him a picture and he said: "Okay, will try. Come back in 2 hours."

Two hours later I was greeted by this nice bottle and a cursing glassblower! 
He growled: "Took me nearly 1.5 hours! Haven't got the right tools with me!" *grrr*"
I said: "Wow! This is really amazing! I knew it was a complicated piece of work and I hope you can forgive me!"
Pleased, that I liked it he said: "Yeah, it was tough but I kind of liked it. 30 Euro and we'll be fine."
Me: " Of course! Thank you!"

Result:

[25 CPS]

Another Tektronix video monitor just popped up here. As often only 50 Euros, but looks alive and more modern that the ones I usually see for sale. So might be a good deal...

For whoever was interested in that the other day ?

https://www.leboncoin.fr/equipements_industriels/2099475645.htm

Buy them.

Then get yourself a sync pulse generator and a couple of cameras with CCUs and you'll be on your way to 75 video bliss.  All you'll need is some 'talent' to stick in front of those cameras to moan and sneer about how institutionalized not-nice-ness is very, very mean and you'll probably be able to get public subsidy for it, too.

[Vince]

Sounds like a plan ! 

.... unfortunately I have zero interest in audio/video/broadcasting/TV stuff.

... so someone else will have to go in the video business ! 

[Specmaster]

I think diesel engines are preferable in winter conditions because of their increased weight and grip as a result of the weight, but also because of their low down pure grunt.

Eh? In another post you advocate selecting 2nd gear to pull away in snow - something that will reduce available torque - and now you're advocating a higher torque engine for winter conditions. You can't have it both ways.

Also the weight argument doesn't cut the mustard. Yes, more weight means more grip, but the momentum/inertia associated with that mass will increase in exact proportion, cancelling out the extra grip which also increases in exact proportion to mass.

Yes, diesel engines in 2nd gear, engine idling and letting the clutch does in fact reduce the torque at the wheel, whereas a petrol or gas engine will more than likely stall unless revs are applied in which case wheel speed increases and slip is more likely. With most modern cars, they are front-wheel drive and the more grip you have, the better. Add a diesel engine into that mix and the extra weight over the driven wheels does infact equate to better grip.

Believe me, it works, I've driven all kinds of cars, front, rear and AWD drive trains and if AWD is not an option then diesel, front is the next best thing.

Torque is torque, it doesn't know whether it's petrol torque or diesel torque. The torque doesn't care if it passed through a slipping clutch or not, each Nm is still just a Nm. An engine will only stall if there is enough grip to provide the necessary opposing force, in which case you were in the wrong gear for the conditions. If you can't pull away in second then you've got enough grip to not have needed to try to pull away in second. There's no subtlety here, this is basic Newtonian mechanics that we all learned when we were 13.

Another advantage with diesel is because of the increased torque at lower RPM, you can very often, as was the case with the buses I mentioned, once you get rolling, change up and leave the engine at idle and the bus pull very nicely and gather sufficient speed to keep you moving at a reasonable and safe speed for the conditions and by using the gearbox, minimise the use of brakes. That is when weight is against you and there is a far greater chance of the wheels losing grip and skidding.

That is still about progressiveness of control and nothing to do with weight, or fuel type. If you're at idle and have got to change gear to add engine braking (rather than just lifting your foot off the accelerator pedal) and you are relying on engine braking then you're in less control than you would be if you selected a higher gear and maintained control with the accelerator pedal. The advanced driving instructors that I used to know (police Sgt. Saunders and his daughter Annette "Fish" Saunders, Annette gave me my advanced motorcycle training) would both give you a proper dressing down for driving like that. I think you're trying to say "In slippery conditions, select a higher gear than you normally would and make use of anticipation and gentle progressive engine braking, rather than inattention and late, harsh braking" - at least I hope you are. In that case the extra torque of a diesel engine at lower revs is neither here nor there because you're trying to minimise the effective available engine braking torque, not maximise it.

Now here's a thing, I was taught to drive by a bus driver and I also went through the advanced bus driver's course (PSV driving school) and that is how I was taught to handle icy and snowy driving conditions. Some buses back then could carry 80 passengers that the driver was responsible for.

There is a significant differance in diesel torque to petrol torque, because maximum diesel torque is produced at a far lower RPM than it is in a petrol engine and anyone who has driven both kinds of motive units will instantly notice it and many don't like diesels because of it.

A gear box is infact a torque/power multiplier in the same way as a pulley block, so starting of in 1st gear with a high torque output engine (ie diesel) is not ideal when the roads are slippery, hence 2nd gear and no throttle is best to use. When it comes to stopping, I was discussing the diesel method that I used to drive the buses when the conditions were bad, therefore I cannot ease back on the throttle and use the engine to brake gently, as it was already at idle speed in a high gear, thus changing down the gears was the only option apart from using brakes. Using brakes with the engine at idle, means using the clutch which means that the brakes then could lock a wheel, not ideal but with engine braking, the wheels are constantly being turned by the engine preventing wheel locking. You get a 10.5 litre diesel engine at idle in top gear, and you are probably going around 20 to 25 mph, ideal in treacherous conditions. Those engines max out at around 2,000 RPM compare that with a typical car engine of somewhere like 4,000 to 5,000 RPM and peak power is anywhere (depending on type e.g. V Tech etc) between 2,500 and max RPM.

The engine in the bus I was driving (Gardener developed max power at 1,600 to 1,700 RPM), my car (diesel max power is at 2,500 RPM, the same car but petrol engined is at 4,500 RPM). Both versions of my car share the same top speed of 138MPH, the diesel has the higher gear ratios to make up for the lower RPMs and hence why I was using the engine's idle RPM to propel the bus along. Any further increase in speed would require the brakes to slow down and with the greater inertia comes greater risks of skidding opposed to engine braking which is keeping the wheels turning until the very last thing. I didn't have a timetable to try and maintain, unlike the service bus driver, so I could afford to take my time and there was no angry passengers standing around at an exposed bleak bus stop waiting for me to arrive.

[kleiner Rainer]

Hi gang,

the photos of video waveform monitors reminded me that I got a Tek 1481C somewhere that a friend who worked for the technical department of the german Telekom gave me several years ago. Went looking for it, and here it is:



It shows the scars of a hard life on the road to TV transmitter sites and some calibration stickers (last one 2004). To test it, I would have to unearth a PAL video source and 75 Ohm BNC wiring. Maybe later...

It also got a special graticule for delay measurements to a FTZ standard.
The serial number B07xxxx indicates it was built in Beaverton, OR. To find out when it was manufactured, I probably have to open it and search for date codes on semiconductors.

Greetings,

Rainer

[m k]

.... unfortunately I have zero interest in audio/video/broadcasting/TV stuff.

You could use one for analyzing your VCR signal and estimate next head cleaning time.

OT car stuff

Generally here a snow itself is hardly an issue.
Icy rain is another thing, like is blizzard, but indirectly.
Problem is windshield and its wipers.
Some conditions are just too much and you can't see hardly anything in no time.
Side wind and a road in the middle of fields is another special case, much more usual for midwesteners I guess.
There you can see just fine but you still can't say how deep the snow is even that you can guess where the road goes.

More car stuff.

One time with FWD, off ramp and icy road.
Speed was too high and the thing went four wheel sliding.
There no traction control felt a better option since gas had no action and I would have liked some.

Other time, icy surface, residential area and short but steep down hill towards a crosswise road.
Can't stop before the road but no problem, snow walls everywhere and the car was SAAB 900.
Just few bumps to the side wall of snow and the speed was slow enough.

Other time big white dog hopped over a tall side wall of snow of main road at night time.
Car was the same SAAB again and the road was empty so no problems there.
I slammed the brakes and skid sound stopper the dog in front of me.
No harm done, I was able to lift the pedal and steer past the animal.

One other time, dark winter time again and a main road with a van I started passing a snow lump.
A bit closer and a lump was a rabbit, I tried to pass it but it turned back and went under.

One other summer day time and equal X-crossing.
I was turning left and tall bush was blocking the view to that direction but it was equal and nobody was coming from the right so I started turning.
When I turned my head to the left, bang, somebody didn't see through that bush.
My vision from that moment reached my maximum prosessing power for vision construction.
The car was blue and that was everything I saw, all the surroundings of the sight were black.

BTW,
I had a sort of a racing licence once, lowest level and mainly for flags.
(zero laps)

[TERRA Operative]

Got the 47pF Input RC Normalizer built, adjusted it on the 4-wire 4276A LCZ meter to 47.01pF. Used some adapters to give me direct BNC connection from the meter to the DUT.

Now to continue tweaking the AM502 differential amp...

[Cerebus]

Some years ago I went to one of those medival markets, which are popular here.
I spotted there a glassblower and asked him, if he could build me a Klein bottle (Kleinsche Flasche).
He asked me back: "A little bottle? (Eine kleine Flasche?)" and I replied: "No. A Klein bottle."
He: "Well, if you bring me a picture, I'll try."
Me: "Okay. " 

Next day I've brought him a picture and he said: "Okay, will try. Come back in 2 hours."

Two hours later I was greeted by this nice bottle and a cursing glassblower! 
He growled: "Took me nearly 1.5 hours! Haven't got the right tools with me!" *grrr*"
I said: "Wow! This is really amazing! I knew it was a complicated piece of work and I hope you can forgive me!"
Pleased, that I liked it he said: "Yeah, it was tough but I kind of liked it. 30 Euro and we'll be fine."
Me: " Of course! Thank you!"

Very cool. To continue the punning, at least you didn't come back  later to be greeted by "Keine kleine Kleinsche Flasche!". 

[mnementh]

   Some years ago I went to one of those medieval markets, which are popular here. I spotted there a glassblower and asked him, if he could build me a Klein bottle (Kleinsche Flasche)...

I can see where that would become a personal treasure; there's something very satisfying in patronizing a local artist.    Brrruce is just such a treasure for me; a consignment from a local artist in San Antonio 20 years ago now. I met him at a art show where my mum was selling some of her stained glass sculptures and we got to talking about metalwork and welding, and I showed him some welding technique I'd learned as he was having trouble with vertical and overhead orientations. In the course of the conversation I asked him what he though about making a life-size landshark and he came back to me with Brrruce a few days later; making it from rebar, sawblades and lag-bolt teeth was all his vision.

He is named after this fellow from Finding Nemo, in case that wasn't obvious.



mnem
*zzzzzzzzzzzzzt... zzzzzt-zzzzzzzzzzzzzt...*

[Andrew_Debbie]

I did a bit more research.
An AC asyncronous induction motor will generate if the Slip is reversed, i.e. it's connected to a AC supply but is being turned faster than the syncronous speed for that supply frequency.
That is fine if it is putting a relatively small amount of power back into a power grid. To use for regeneration in a DC storage system is more interesting.
The Tesla S motor has a speed sensor disc on the shaft. I'm making assumptions here, but suggest that the controller uses the signal from this to generate a lower than current syncronous speed "excitiation" signal to the stator. Presumably this has a low amplitude and a lot of slip. Slip can be considered a phase shift between the excitiation and generated sinewaves. You can then use a syncronous (to rotor speed) rectifier to exract DC from the generated waveform without taking power from the excitiation. It seems 60 degrees of slip would be optimum for a 3 phase system.

So not as complex as I first thought but nowhere near as good a generator as a PM or "DC" rotor system.
Note car alternators are DC rotor systems and can be used as motors using BLDC type motor drives.

Tesla S and X   use induction motors. 
BMW calls the iX3 machine a "current-excited synchronous electric motor"  which on very brief examination sounds a lot like what Tesla are doing in the Model S. 
Renault Zoe and Kangoo:  electrically (DC) excited synchronous motor or EESM.  Also called a wound rotor.   The first generator Renault motor was made by Continental, but Renault make their own now.

Just about everyone else are PM rotor  synchronous.   Actually most of them are "mild" hybrids rather than pure PM.   This is done to reduce the amount of rare earth magnets needed and perhaps to improve performance.

BMW i3  is a hybrid.  It uses half the rare earth PMs that a LEAF motor but has more power.   The Tesla Model 3 motor is similar.  I'm not sure if they licenced BMWs patent or found a work around.   



2015 paper outlining the various types in use at the time:

https://www.researchgate.net/publication/273791124_Electric_vehicle_traction_motors_without_rare_earth_magnets

[25 CPS]

Hi gang,

the photos of video waveform monitors reminded me that I got a Tek 1481C somewhere that a friend who worked for the technical department of the german Telekom gave me several years ago. Went looking for it, and here it is:

(Attachment Link)

It shows the scars of a hard life on the road to TV transmitter sites and some calibration stickers (last one 2004). To test it, I would have to unearth a PAL video source and 75 Ohm BNC wiring. Maybe later...

It also got a special graticule for delay measurements to a FTZ standard.
The serial number B07xxxx indicates it was built in Beaverton, OR. To find out when it was manufactured, I probably have to open it and search for date codes on semiconductors.

Greetings,

Rainer

Actually, if Vince were to do that muticamera setup I was tossing around there, he'd need a video switcher.  And that's where the waveform monitor comes in, because as soon as you add a video switcher to the mix, it opens the door to all kinds of timing problems.  PAL's nicknamed Problems Are Lurking for a reason!

Once it's all sorted out though, he can have some "talent" in front of the cameras doing a debate about whether tap water can be considered 100% ethically sourced vegan or not.

[Andrew_Debbie]

I am  set to bid on this Racal Dana 1998  Counter:

https://www.ebay.co.uk/itm/393856305682


no photos of the rear panel.  I am assuming it has the least desirable options.