Test Equipment Anonymous (TEA) group therapy thread

[kj7e]

I just found my next bike, thanks to this group;

[AVGresponding]

I bought a thing. Because it.. expands my capabilities. Not that I would need them right now. But it was cheap...
Time to get into toobes?

Either toobs or electrophoresis...




I am currently realising how expensive stupid RF connectors are; was thinking to use them for the internal interconnects in the dual 584 reference project, but given the cost I may just use RCA plugs and sockets instead!   

Since it's a DC application where I just need shielded cables and connectors I think it'll be ok, AC impedance should be irrelevant. Hence I will also use the cheapest coaxial cable I can find also.   




EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/

[mindcrime]

EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/[/color][/size][/b]

Oh man... I'd LOVE to have a 60kv power supply!  For what? I have NO idea, but it seems awesome. Talk about extending your capabilities!?!??? Wow. #WANT

[ch_scr]

I bought a thing. Because it.. expands my capabilities. Not that I would need them right now. But it was cheap...
Time to get into toobes?

Either toobs or electrophoresis...

[...]

Yeah, but while this is marked and marketed for electrophoresis, it really is "just" a linear supply. At least it does seem like that to me and I really hope I am right at that
All the newer electrophoresis supplies have a lot of safety (ground leakage, minimum turn on current, limited Vout up ramp speed) and "comfort" (constant power, voltage steps, timer, V-hr mode) features. While it makes them safer and more convenient for their intended purpose, it makes them annoying for bench use.
This thing is beat up and sold as "for parts", but at 31€ I really can't complain. Let's hope the seller ships it well packaged 
If I can't find a use, I bet it could be ferengi'd pretty well when listed as "tube power supply" 

Edit: Also, at least on the one newer Bio-Rad smps I had a play, the control loops were tailored to the stable, resistive loads of gel-electrophoresis. It freaked out a bit when connected to the nonlinear load of a neon tube. 
At least it did not blow itself or the neon, but they normally don't glow THAT bright...

[25 CPS]

I just found my next bike, thanks to this group;

At a penny farthing, the price is right too.

[AVGresponding]

ftp://

EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/[/color][/size][/b]

Oh man... I'd LOVE to have a 60kv power supply!  For what? I have NO idea, but it seems awesome. Talk about extending your capabilities!?!??? Wow. #WANT

I feel the same way, but just can't justify either the expense or the space at the moment. I can't imagine the shipping costs to the US being in any way sensible or reasonable...

Yeah, but while this is marked and marketed for electrophoresis, it really is "just" a linear supply. At least it does seem like that to me and I really hope I am right at that
All the newer electrophoresis supplies have a lot of safety (ground leakage, minimum turn on current, limited Vout up ramp speed) and "comfort" (constant power, voltage steps, timer, V-hr mode) features. While it makes them safer and more convenient for their intended purpose, it makes them annoying for bench use.
This thing is beat up and sold as "for parts", but at 31€ I really can't complain. Let's hope the seller ships it well packaged 
If I can't find a use, I bet it could be ferengi'd pretty well when listed as "tube power supply" 

Edit: Also, at least on the one newer Bio-Rad smps I had a play, the control loops were tailored to the stable, resistive loads of gel-electrophoresis. It freaked out a bit when connected to the nonlinear load of a neon tube. 
At least it did not blow itself or the neon, but they normally don't glow THAT bright...

Yes, both my "baby" 300V 90W and my ludicrous 2.5kV 100W are annoyingly safety-focused, presumably as they are intended to be used by people with a more limited understanding of electricity. Fortunately the 2.5kV unit is easily fooled, being an older piece of gear. The 300V one is fully computerised, so the safety is harder to defeat. Not impossible though...   

[Cerebus]

I just found my next bike, thanks to this group;

At a penny farthing, the price is right too.

I think you'll find that's more in the region of Krugerrand-Sovereign than Penny-Farthing. 

[Robert763]

TEA package arrived today.
Should have six items in it but the packking is not looking good.  Even Hermes thought it needed more tape 
Two heavy units. a resistve load bank and a AC power supply with no packing between them 
At least the meters were in a cheap ply and thin aluminium case.
The powersupply is an odd one basically a 200VA 15V transformer in a box with some werd switching and binding posts. I had not realised it was part of the bundle so total bonus.
The loadbank had two toggle switches broken. How the meter survived I've no idea. It has 6 power resistors switched by relays. They are fan cooled. The control behind the select toggle switch is complex. There is a bicolour LED by each toggle to indicate the state and then a bunch of logic to light up "maximum votage" (power) LEDs.
It is reallly well built and everything is crammed in. The 6 toggle switches are fixed to a sub panel and once the front nuts are removed they come out as a block so easy to change out the broken ones. all but 1 are 4PCO presumbly 3 of the poles are used for the LEDs.
Each resistor has 2 relays for 12 total. There is a mains transformer in there too.   
Once the switches were changed it all works 

Next on the list was the Fluke. It's a basic 8022B. Stuck a battery  in it and LCD is fine but no response to volts and ewird readings on Ohms. Checked input resistance and it's open circuit 
Must be either an input resistor or a switch fault.
Quick check showed the 1k and 100k resistors on the +Ve terminal (R1 & 2) are faulty. The 1k is open and the 100k is 200k. Replaced those and the battery snap (corroded) and it works 
Photo shows it next to to a 89IV and its pretty good. Broke out the 6.5 digit and it's the 89 that is out by about 9mV. The 8922B was spot on without any adjustment. Can't beat an (old) Fluke
I think I'll just flip the Metrotest stuff I got an all in one installation tester already.
Dispite the issues it's still a bargain for <£30 shipped I'm sure the £3.20 postage cost was a mistake 

[mindcrime]

I feel the same way, but just can't justify either the expense or the space at the moment. I can't imagine the shipping costs to the US being in any way sensible or reasonable...

Yeah, same here. And as cool as it would be, I have my "the last two or three things I could possibly ever need" wishlist with a couple of higher priority items right now. 

[tggzzz]

EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/

I suppose I need a 60kV Brandenburg PSU to test my 40kV Brandenburg voltmeter.

Or vice versa.

[AVGresponding]

EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/

I suppose I need a 60kV Brandenburg PSU to test my 40kV Brandenburg voltmeter.

Or vice versa.

Without doubt!   

[mnementh]

TEA package arrived today...



...Despite the issues it's still a bargain for <£30 shipped I'm sure the £3.20 postage cost was a mistake 

   

That resistor bank behemoth reminds me very much of a monster I fabricobbled back in the day for load testing/burn-in on high current car audio amps... 

mnem
"It's not the volts, it's the amps that kill you..."

[mnementh]

I just found my next bike, thanks to this group:   

MmmmmHmmmm... I gotta think there's less expensive ways to commit stoopit-cide... 

mnem
 

[kj7e]

Not so much TEA, but what I have been working on for the last 9 months, and just the day before yesterday I got the plans approved and building permit issued.

New Tashjian Towers DX70 crank up tower.  Going to hold a SteppIR DB36.  I dug the 4'x4'x9.5' hole by hand, last year over labor day.  Why did I have to do this over one of the hottest days of the year?

I've had towers in the past, but this one was a PITA to get a permit for, it meets the planing and zoning development codes, but since I live in unincorporated Los Angeles county, it was a major task to meet their requirements.  Soils reports, fault zone and seismic + liquification reports.  I also had to have an outside Geotechnical firm re-stamp the plans, despite they were already stamped.  Oh, and the cost of the permit was something else, nearly as much as the tower itself.  Since it will be 3000psi concentrate, I have to have both an official observer and an deputy inspector for the construction and pour.  They don't seem to care its not a bridge, or hospital.  Its a stick in the ground.  Okay, starting to rant.

[tautech]

 
Wow kj7e, you're keen!
Didn't you know anyone with a digger and drill head ?

Cool looking tower. 

[med6753]

Not so much TEA, but what I have been working on for the last 9 months, and just the day before yesterday I got the plans approved and building permit issued.

New Tashjian Towers DX70 crank up tower.  Going to hold a SteppIR DB36.  I dug the 4'x4'x9.5' hole by hand, last year over labor day.  Why did I have to do this over one of the hottest days of the year?

I've had towers in the past, but this one was a PITA to get a permit for, it meets the planing and zoning development codes, but since I live in unincorporated Los Angeles county, it was a major task to meet their requirements.  Soils reports, fault zone and seismic + liquification reports.  I also had to have an outside Geotechnical firm re-stamp the plans, despite they were already stamped.  Oh, and the cost of the permit was something else, nearly as much as the tower itself.  Since it will be 3000psi concentrate, I have to have both an official observer and an deputy inspector for the construction and pour.  They don't seem to care its not a bridge, or hospital.  Its a stick in the ground.  Okay, starting to rant.

Better you than me. There's a reason they call it "Commiefornia" 

[kj7e]

Wow kj7e, you're keen!
Didn't you know anyone with a digger and drill head ?

Cool looking tower. 

I had to be very surgical in the dig and with very limited room for equipment due to the surrounding walls and such.  That and I kind of enjoy the workout.

[VK5RC]

@kj7e. Ooooooooooh, serious tower envy 👍🗼

[tautech]

Wow kj7e, you're keen!
Didn't you know anyone with a digger and drill head ?

Cool looking tower. 

I had to be very surgical in the dig and with very limited room for equipment due to the surrounding walls and such.  That and I kind of enjoy the workout.

You're one sick puppy ! 
Still, a 6t digger with a 3' auger could break the back of such a project and you'd just need to square and clean the hole.

[mnementh]

Nice Burmese Tiger Trap. Who's the numb-nuts you trapped in it...? 

No, seriously... well done. 

I've dug more than a few such holes... that is definitely an accomplishment; all to disappear shortly when the concrete truck arrives. 

mnem
*peels gloves off at end of 2nd day* "Oi... I've got blisters on me blisters..." 

[mnementh]

Boring Mundane Everyday Interesting Fun Project Print #788: Thumb Throttle for eBike

     

While I wait on bits for my fatBike, I've dragged out the boy's 26" MTB which has that hub motor already installed. This kit came with a motorcycle-style twist-throttle; it simply will not work with the MTB which is equipped with twist-shifters both sides already. So, I hacked the twist-grip apart and made this part to convert it to a thumb-throttle.



And here it is, all put together on the bike; while I was in there, we upgraded to a 4" riser gooseneck and installed the brake levers from the eBike kit which have kill-switches for the ESC in them.

With all that crap in one spot on the handlebars, getting everything right where it needs to be is a bit of a juggling act. For now, I have the thumb ring bonded to the magnet ring with just 3 dots of CA until we have a chance to test it, just in case I have to break it apart and re-clock the thumb-peg to a different idle position.

I really like this arrangement; it feels quite natural with the thumb-peg wrapping around the body of the twist-shifter. I like it better even than the thumb-throttle I paid money for to put on my fatBike.     I may wind up doing this again real soon...

For those who are interested, details and 3DP Nerd-stats are available in the 3DP Thread:

https://www.eevblog.com/forum/3d-printing/3d-printer-yet/msg3585793/#msg3585793

mnem
 

[vk6zgo]

I just found my next bike, thanks to this group;

Back when I worked close to town, & often took the route along "Riverside Drive" skirting the City's edge before heading further down river to work, I saw many strange things, as well as just people enjoying a morning walk, or on their way to work in the CBD.
For instance, I had never heard of "river dolphins" till I saw several hunting in the shallow waters of the Swan River.

Nothing tops the big guy, who looked like an old fashioned circus strongman, even down to the heroic mustachios, though.
He routinely rode a unicycle to work.

[mnementh]

EDIT: For even more tzzzztt this has just popped up for sale on the forum: https://www.eevblog.com/forum/buysellwanted/fs-(uk)-brandenburg-eht-adjustable-power-supply-60kv/[/color][/size][/b]

Oh man... I'd LOVE to have a 60kv power supply!  For what? I have NO idea, but it seems awesome. Talk about extending your capabilities!?!??? Wow. #WANT

https://www.banggood.com/DC-12-36V-10A-300W-ZVS-Tesla-Coil-High-Voltage-Genrator-Driver-Board-Discharge-Flyback-Module-p-1254406.html

These will get you 30-50KV depending on exactly which flyback is used and how hard you drive it/how much you're willing to risk toasting it.

These are pretty easy to build from scratch; just do a quick Gurrgle on "Zero Voltage Switching Tesla" and you'll be knee deep in all sorts of HV tomfoolery before you know it.

These kits are a pretty cheap & easy way to get a circuit & components that are pretty well-matched & known to work tho; I've seen them as cheap as $12 on a random Amazon blowout.

I built my first such plasma ball out of a 6" clear globe-style light blub and a push-pull oscillator when I was 13. 

mnem
tzzzzzzzzzzzzt.....

[Specmaster]

And now for something completely different, as you might know, there is a little something going on in Cornwall UK, called the G7 Summit and there is one nation that will more than likely be lecturing the other member nations about the need to tackle climate change, just a shame that they don't lead by example, who is it, why it's the USA, who else. There has been an insane amount of transatlantic flights undertaken by hoards of C17's and C5's and presidential planes along with the relocations of loads of KC135, Hercules and Ospreys into Newquay, Brize Norton, Stanstead, Mildenhall, Lakenheath, Fairford and Northolt. I'd hate to think about the carbon footprint of that operation so far, which has one more airport to add to its list on Sunday, Heathrow, when the President departs for NATO meetings and the First Lady returns to the White House.

That said, it has been a dream for my son and I with all the photographic opportunities. Wednesday we were at Mildenhall hoping to catch a busy day of operations, but we were disappointed as it was in a lockdown in preparations for the arrival of AF1 and support aircraft amid a massive security operation all around the airfield with photographers lining the road outside the base being moved on by police. That said, however, there were 2 locations we were allowed in, not ideal as it meant shooting through a chain link fence but for those interested people here are a couple of photos I managed to get after waiting around for almost 10 hours.

I will be trying to get some better shots of these departing Heathrow on Sunday if we can find a location that we will be allowed to shoot from. 

After Sunday, all of those aircraft movements and support flights on the C5's and C17's will be reversed again in order to return all the cars, helicopters etc, back where they came from.
 

[Neomys Sapiens]

I bought a thing. Because it.. expands my capabilities. Not that I would need them right now. But it was cheap...
Time to get into toobes?

Either toobs or electrophoresis...

[...]

Yeah, but while this is marked and marketed for electrophoresis, it really is "just" a linear supply. At least it does seem like that to me and I really hope I am right at that
All the newer electrophoresis supplies have a lot of safety (ground leakage, minimum turn on current, limited Vout up ramp speed) and "comfort" (constant power, voltage steps, timer, V-hr mode) features. While it makes them safer and more convenient for their intended purpose, it makes them annoying for bench use.
This thing is beat up and sold as "for parts", but at 31€ I really can't complain. Let's hope the seller ships it well packaged 
If I can't find a use, I bet it could be ferengi'd pretty well when listed as "tube power supply" 

Edit: Also, at least on the one newer Bio-Rad smps I had a play, the control loops were tailored to the stable, resistive loads of gel-electrophoresis. It freaked out a bit when connected to the nonlinear load of a neon tube. 
At least it did not blow itself or the neon, but they normally don't glow THAT bright...

I was wondering since seeing some of those 'electrophoresis' power supplies around here and on sale whether they have the 'rectangular' U/I characteristic, which is generally the hallmark of laboratory PS, at all or not. Could you be bothered to verify on your example?