Test Equipment Anonymous (TEA) group therapy thread

[Cubdriver]

Storm #2 is clearing out - much less snow than the one last week.



-Pat

[Specmaster]

How in the hell did these ever remain flying when they had Lucas electrics? 

Simples, Lucas weren't as bad as people make them out to be. A lot of the problems were more than likely caused by the car manufacturers themselves.

[Specmaster]

That Landy is a clear winner, winner, chicken dinner!

Which you would be able to cook on the firebox.

If everyone had something similar then we would be seeing the possible return of Tuberculous and the infamous pea soup smogs that used to be the norm in the 70's.

I can remember driving a Ford D series truck through those deadly smogs and no word of a lie, in London and other towns and cities, when they were bad, visibility would be down to about 60 feet or 2 bus lengths at most and more people were dieing as a result of breathing that pollution, then there are people dieing today as a result of pollution. I think that there was far more damage to the global warming back then than there is now. Nowhere near as many people burning wood or coal/coke to keep warm and heat water and these days engines are considerably more efficient with MPG and BHP doubled or even trebled in real terms and far cleaner exhausts. 

[bd139]

Heads up for the UK TE buyers. Don’t buy this: https://www.ebay.co.uk/itm/224343146214

This is the one I sold that blew up 



Apparently smoke comes out under load.

[Specmaster]

Thats a crap design with the power cord entering via that hot surface. It must get pretty hot to have a warning sign like that applied to it surely 

[bd139]

There’s a large gap. Only the top gets hot. The bottom is a red strip across the barrier strip for programming as there are high voltages there.

[Specmaster]

Oh, OK

[factory]

Heads up for the UK TE buyers. Don’t buy this: https://www.ebay.co.uk/itm/224343146214

This is the one I sold that blew up 

Apparently smoke comes out under load.

If you refunded them, why didn't they return it? Bit dishonest if they are selling it and you did refund them.

David

Edit: Added that seller to my blocked bidder list.

[bd139]

I refunded it and said they could do with it what they pleased. If that’s selling it, up to them. I am somewhat done with HP supplies 

I am retaining a singular TTi PL320 at the moment and that’s it.

I have a 6205b with bust range switch on channel A soon if anyone is interested (UK only). I have yet to locate a suitable box for it though so might be a while before I can send it.

[Cubdriver]

Thats a crap design with the power cord entering via that hot surface. It must get pretty hot to have a warning sign like that applied to it surely 

They're load resistors, enclosed in a little box that hangs of the rear of the supply.  The mains cord ducks under them and is fed into the rear of the enclosure in the same place it is on the other, similar supplies in that series.



-Pat

[factory]

I've also been working on the donor board from Sphere for the 5243L, the original had the same photo-resistor plate corrosion problem as the 5248M giving multiple numbers lit at the same time.


All the resistors & transistors in the green box were removed & replaced with the correct parts as the original had.


On testing it initially had some ghosting of other numbers, but in the time it took me to have a look through the manual it had corrected itself, guess it just needed some use. Still need to relabel the board with the correct part number.


There is at least one problem still to fix, the heater control circuit for the crystal oven, it doesn't turn the heater on at all.
And it needs the wiring loom modification to allow use of later plug-ins.

David

[beanflying]

Signs of life. Quick power up, most of the soft buttons seem to work, relays click in and out and drawing about the correct current.

Double shot Coffee then see if it is a dead display or find the manual and play with the contrast maybe So far better than expected for the few pesos.

[factory]

Thats a crap design with the power cord entering via that hot surface. It must get pretty hot to have a warning sign like that applied to it surely 

They're load resistors, enclosed in a little box that hangs of the rear of the supply.  The mains cord ducks under them and is fed into the rear of the enclosure in the same place it is on the other, similar supplies in that series.



-Pat

I wonder if the smoke smell from the ePay one is a RIFA problem or the smell of hot dust from those power resistors.   

David

[mansaxel]

P.S.: Don't place too much trust in the ability of gas stations to provide your KESSELSPEISEWASSER!

The treatment of steam engine  water supplies is a complicated matter. You want just the right amount of chemicals in your water, and since you're not condensing but just "topping up" (to the tune of several cubic metres per day for most engines) all the time, there are some interesting points:

• You really, really will want to be sure to be able to top up. If boiler water levels sink to below firebox roof, you have a boiler explosion coming, sure as RIFA.
• Thus, your treatment must be economical, and at the same time adapted to the local chemistry at the watering point.
• Some machines can't deal with the steam from such plants, like steam turbines. Both the Reichsbahn turbine trials and the SJ/NOHAB engine were equipped with condensers and a closed feedwater system.
• Same applies in desert situations, a condenser has been the solution for some desert lines. Good luck running a condenser in 35°C..

[mansaxel]

Dinner would taste of WD40 and moss though.

No, you don't use WD40 on a steam engine. You use proper steam oil.

[vk6zgo]

How in the hell did these ever remain flying when they had Lucas electrics? 

I don't think they did use Lucas equipment!

Obviously, I wasn't around during the Battle of Britain, but looking at old copies of "The Aeroplane", & other publications of the period, I have the distinct impression that such stuff was made/designed by a different, specialist, manufacturer.
Lucas may have made some parts under contract, like many others did, however.

Joseph Lucas always struck me as having a hubris problem, & were sure they were the best, in the face of mounting evidence that they were not.

I think that is the only explanation as to why they didn't just buy some Bosch stuff & reverse engineer it to find out what that company did right, & Lucas did wrong.

The Solex & Zenith carburettors so beloved of Brit carmakers in the 50s are another example:-

The Stromberg single barrel downdrafts used by Holden were simple, rugged, & reliable, in fact, there was a thriving cottage industry in Oz, back in those days, rejetting Strombergs & fitting them to "Pommy" cars, to replace the fiddly, fussy OEM carbs.

[mnementh]

      

ON THE BENCH TONIGHT: Making the World's Tiniest PCB!   

That's it right there... two whole holes worth of 0.100" pitch perfboard. Why? To support that hair-thin bit of hardened brass wire off one of these Ardu vibration sensors so I can install it in my favorite T12 soldering iron handle. That wire is actually the other end of a tiny coil spring; it is uber-brittle and will snap off flush at the slightest wiggle.

This PCB serves as a base so I can solder pigtails of more workable soft enameled copper wire on it. Add a little Kapton tape as insurance, then bundle the whole thing up in heat-shrink and we're good to go for another year or three. 

Oooohhh... it is so nice not having the damned thing go to sleep all the time while I'm using it; almost like using a different soldering station altogether. 

mnem
*tssssst....*

[Specmaster]

How in the hell did these ever remain flying when they had Lucas electrics? 

I don't think they did use Lucas equipment!

Obviously, I wasn't around during the Battle of Britain, but looking at old copies of "The Aeroplane", & other publications of the period, I have the distinct impression that such stuff was made/designed by a different, specialist, manufacturer.
Lucas may have made some parts under contract, like many others did, however.

Joseph Lucas always struck me as having a hubris problem, & were sure they were the best, in the face of mounting evidence that they were not.

I think that is the only explanation as to why they didn't just buy some Bosch stuff & reverse engineer it to find out what that company did right, & Lucas did wrong.

The Solex & Zenith carburettors so beloved of Brit carmakers in the 50s are another example:-

The Stromberg single barrel downdrafts used by Holden were simple, rugged, & reliable, in fact, there was a thriving cottage industry in Oz, back in those days, rejetting Strombergs & fitting them to "Pommy" cars, to replace the fiddly, fussy OEM carbs.

They may have used CAV which was the commercial division of Lucas making primary diesel injection pumps and electrical bits for buses, marine craft and trucks IIRC there was also another company called SIMMS who did similar.

[tautech]

They may have used CAV which was the commercial division of Lucas making primary diesel injection pumps and electrical bits for buses, marine craft and trucks IIRC there was also another company called SIMMS who did similar.

Dunno if CAV was around back in the 40's but certainly in the 70's when my TK Bedy was built with a 100A 24V CAV alternator and diesel system.

[SilverSolder]

[...]
Joseph Lucas always struck me as having a hubris problem, & were sure they were the best, in the face of mounting evidence that they were not.

I think that is the only explanation as to why they didn't just buy some Bosch stuff & reverse engineer it to find out what that company did right, & Lucas did wrong.
[...]

I once had a great chat with an elderly gentleman who worked for Lucas in that period.  He explained that the Lucas men knew what they were doing, but they were asked to crank out production on ancient and well worn machines that couldn't maintain precision.  This meant that good designs ended up being badly implemented, as well as bad designs being chosen simply because the old machines could make them.   He put it all down to lack of investment and lack of respect for the engineering profession by the British upper class at the time.

[Kosmic]

Got a new voltnut toy and it's a Keithley



A deal popped on ebay and I couldn't resist. Bought this Keithley 182 nanovoltmeter to replace my Keithley 181. They both use the same connector and leads so it's an easy upgrade for me. Compared to the 181, the 182 has a little bit more resolution and less noise. It's also more modern and got more filtering, buffering and triggering options.

I removed the shield over the analog section to take this shot. The meter use the LM399 voltage reference like many other 6.5digits meter.



Close up on the input section of the PCB. This is where the magic happen. The input resistor is crimped and then screwed to the board to limit thermal EMF (only bare copper to bare copper contacts).



My old nanovoltmeter will soon start its voyage to the bay.

[Kosmic]

I shall look out for a quiet one! 

Hp was selling a conversion kit at some point. My guess is that it was simply some wires and a aluminum plate that fit the hole in the back.

Kosmic,
Do you have more information about this change?
What exactly was the purpose - intention?

Regards, Frans

I don't know the reason. Probably to lower production cost and eliminate failure points.

Some pictures of my 3456a with the fan:





The fan main purpose of the fan is to cool down the digital section of the meter (the analog section is isolated). And on that section the only thing that can generate heat is the big transistor mounted on a tick bracket connected to the aluminum chassis. The transfo can probably produce a little bit of heat but that's generally not a problem.

I think they inherited that design from the 3455a and then realized they could drop the fan by moving the heat source outside the enclosure. It's mostly speculation from my part but I think it's plausible.

[beanflying]

NE1 got a service manual  Fluke 105B Scopemeter. I do have the User manual.

Most soft switches seem to work as the relays click in and out. Main rail to the LCD is -29.3 against a labelled -30 so should be close and not the cause. +5V rail seems fine too. That little board was sitting partially off like that too when I took the shield off and the rear case is trashed (10-12 bits) so it has had a significant thump at some stage. Local DOD sticker shows it as being in the Leopard Fleet so wonder if there was a Tank involved 

The only service manual I could find that is remotely close is the older PM 93-97 Philips branded range which is still a similar layout and topography but a very different series of Chips and display so not a lot of use. https://www.cl.cam.ac.uk/manuals/pm93_95_97_fluke_93_95_97.pdf

More playing tomorrow.....

Edit - Tried the Software and it won't install in compatibility mode as it looks for the actual OS when the installer runs 

[tautech]

Time to break out the Flir bean ?

[beanflying]

Time to break out the Flir bean ?

Still on my wish list