Test Equipment Anonymous (TEA) group therapy thread

[tautech]

Yes they send the wrong stuff out all the time. Sometimes you win, sometimes you lose.

RS lucky dip ? 

[AF6LJ]

To get away from 20's era battery sets and back onto test gear, I finally got ambitious and got the Agilent 8644B that arrived from the 'bay around Christmas back up and running.  It had a shorted cap in one of the modules.




I realize that the modules are needed for shielding and ease of construction, and that capability-wise it blows the older gear out of the water, but it still looks kinda boring inside compared to the old stuff that's packed to the gills with visible circuit boards.

Still, nice to have it operational.  Thread on it here:
https://www.eevblog.com/forum/testgear/hpagilent-8644b-synthesized-signal-generator-bad-cap-repair/

-Pat

Nice catch, and I agree the newer stuff doesn't have that look some of the gear from the seventies, and eighties does.

[Brumby]

This is definitely a mistake. I just had two boxes of 4000 arrive!



That cost me £2.71 including next day delivery

So .... how long will those 8,000 resistors last you?

[bd139]

I'll probably get through 200-300 or so before I drop dead at current rate.

So I will clearly have to be buried with them.

[Specmaster]

I'll probably get through 200-300 or so before I drop dead at current rate.

So I will clearly have to be buried with them.

They can make my coffin with the remains of my 20,000 of em then 

[bd139]

Hahahaha I wonder how long before they notice

The stupid thing I can see is that the box has "quantity 4000" on it. Then they stuck another stock label on with "quantity 1000" and then they sold it for "quantity 20" price. 

[Specmaster]

Hmm, I'm wondering the same, I've got 4,000 on back order!

[bd139]

Someone probably got there before you. I'd phone up and cancel that as it'll revert to normal pricing.

[Specmaster]

Already paid for them

[bd139]

They only take payment for shipped stuff usually.

[Specmaster]

Correct, just checked, they didn't charge for them, oh well, if they do then, what I've planned will cover them anyway, but hopefully they will be the same price. 

[Specmaster]

I'm stupid  maths never was my strong point, but I've double checked and triple checked, I have already been charged for them so that should be OK, dispatch date is the 27th.

[bd139]

Ah that's fine 

[Specmaster]

Win! Mine hasn't arrived yet

They're really good resistors. 50ppm tempco 1% 600mW.

I'm going to build an HF dummy load (6/12W undecided) with mine when they turn up. Need to work out a fun topology where they won't desolder themselves first

Pcb with 2 rails and then you'll have lots of air round them to help disapate the heat both soldering and in use?

[BravoV]

Do this things count as TEA purchase ? 

Resistance of 1K, 10 miliOhm and 1 miliohm shunts, with 0.1 % tolerance and TCR of 30-50 ppm/K.
Tempted by their nice resistance numbers.

[Cerebus]

I took a relative to watch the last flight past W-s-Mud; he was delighted since he was an apprentice at Filton in the 60s. Watching a heavy bomber stand on a wingtip ought to be impossible, but we saw it that day.

I've seen quite a lot of footage from that flight and it's obvious that the conversation in the cockpit went something like: "OK, boys. It's her last ever flight, let's get creative and see what she'll do".

The only thing about seeing that flight that didn't make me happy, apart from the obvious "last flight" nature of it, is that someone really ought to have got a couple of English Electric Lightnings out of mothballs as a fighter escort. 

[Specmaster]

I took a relative to watch the last flight past W-s-Mud; he was delighted since he was an apprentice at Filton in the 60s. Watching a heavy bomber stand on a wingtip ought to be impossible, but we saw it that day.

I've seen quite a lot of footage from that flight and it's obvious that the conversation in the cockpit went something like: "OK, boys. It's her last ever flight, let's get creative and see what she'll do".

The only thing about seeing that flight that didn't make me happy, apart from the obvious "last flight" nature of it, is that someone really ought to have got a couple of English Electric Lightnings out of mothballs as a fighter escort. 

Sadly the CAA won't allow English Electric Lightening to be flown by civilians. The only place you still them flying is South Africa I believe there is someone there who has one.

[bd139]

Win! Mine hasn't arrived yet

They're really good resistors. 50ppm tempco 1% 600mW.

I'm going to build an HF dummy load (6/12W undecided) with mine when they turn up. Need to work out a fun topology where they won't desolder themselves first

Pcb with 2 rails and then you'll have lots of air round them to help disapate the heat both soldering and in use?

That would be too easy. I've got some left over ring main flex which has proper thick copper in it. Figured I can build a rolled radiator pattern. I played with 3d topologies but you can't get an equal load across each of them which means hot spots and meltdowns.

Assuming I'm using 100 ohm resistors, of you have N resistors in series, that gives you a total R of N*100. Now to bring that down to 50 ohms you need (N*100)/50 of those in parallel.

So 5 resistors results in 10 bars of 5 resistors = 50 total = 30W.

Lets go mental: 10 resistors results in 20 bars of 10 resistors = 200 total = 120W.

Lets use ALL the 8000 resistors = 4.8KW 

SWR of that will probably be horrid though

[mnementh]

On to my T12 Project:

So I found and ordered a SSD-1306 driven 1.3" OLED display yesterday as I had a small windfall via PayPal and didn't mind paying like $3 extra to get it this month instead of sometime in March from China. I just got an eMail telling me it shipped... and tracking shows it about halfway here already. I could actually have it by Saturday (knock on wood).

Meanwhile, the KSGER gear I ordered almost 3 weeks ago... showed "Processed through a facility in Shenzhen" on Feb 2nd and hasn't updated since.  Either it got on a plane, or it fell off the alpaca's back somewhere between Wutong and Nanshan mountain. 

*Carefully places the soldering station to the back of the workbench and turns off the lights*


mnem
"...and stars in my pocket like grains of sand..."

it's Chinese New Year holiday's mate, I've got a batch of gear being manufactured by Elecrow atm and it's been delayed by 2 weeks due to the holidays.

Oh, I'm painfully aware of the pitfalls of CNY, trust me. I've been buying components from China for decades. This stuff was ordered 3 weeks ago and like almost everything I order this way, I paid for ePacket; all they had to do was get it to the USPS Depot in Shenzhen. From there, it's on the USPS calendar, not mainland China's.

Some vendors just don't know how to process ePacket correctly; about half the time they use China Post to get it to the USPS Depot (totally defeats the purpose) and if they use the China Post mailing app, it gets processed as if it were a China Post parcel, NOT ePacket.

If it's processed correctly with a USPS ePacket label, it takes 10 days or less from the time they get it at the USPS depot; this is what ePacket was invented for; to get components from China into US devs and engineers' hands without waiting forever and costing more than they're worth.

To get away from 20's era battery sets and back onto test gear, I finally got ambitious and got the Agilent 8644B that arrived from the 'bay around Christmas back up and running.  It had a shorted cap in one of the modules.
 

I realize that the modules are needed for shielding and ease of construction, and that capability-wise it blows the older gear out of the water, but it still looks kinda boring inside compared to the old stuff that's packed to the gills with visible circuit boards.

Still, nice to have it operational.  Thread on it here:
https://www.eevblog.com/forum/testgear/hpagilent-8644b-synthesized-signal-generator-bad-cap-repair/

-Pat

Actually, all that shielding and $20/foot cabling with $20 connectors on each end just screams "lots of electrons being tormented, molested and abused at very high frequency" to me. Turnabout is fair play, says I. 

It reminds me of pics I've seen of the equipment inside of 70s-80s vintage satellite gear and some of the stuff from various NASA missions I've seen.  i've always been a junkie for pics of the nuts & bolts of that kind of high-tech; doesn't matter to me if I understand how it works or even what the particular device does; I'm still just fascinated by it in the same way I am with high KW commercial broadcasting gear.

Starting to wonder if the dills at Pittney Bowes in Erlanger are on Chinese New Years as well. 6 days since my 5326B moved 



edit : Wonder what the problem might be..

Have you been licking live traces again, bean?  What's this; your 704B?

Yep, the Vulcan was capable of being flown like a fighter, even rolled and at high altitude nothing came close to matching its ability.

Check out some videos of the B-1B. It can be tossed around like a fighter too.

I've always had a soft spot in my heart for Delta wing jets; when I was wee little I had a picture book about what they imagined space "life" would be like back in the 60's, and all the "commuter" ships in that book were Deltas of varying size. That was a favorite book pretty much until it disintegrated from being thumbed through & reread over & over again while listening to "Rocket Man" and "Major Tom", etc at high volume.   

We all got cheated, man. Big time.

Hahahaha I wonder how long before they notice

The stupid thing I can see is that the box has "quantity 4000" on it. Then they stuck another stock label on with "quantity 1000" and then they sold it for "quantity 20" price. 

They are some odd values though, so maybe they want to reduce stock levels a bit?

I'm thinking exactly this. following required Chain of Custody protocols for disposing of e-Waste in their commercial setting may be quite costly due to the management-level man-hours involved; it may be cheaper to give the stuff away AND eat the shipping (after tax write-offs, etc) through normal channels than to pay for it to be handled as e-Waste.

This is definitely a mistake. I just had two boxes of 4000 arrive!



That cost me £2.71 including next day delivery

*SCHWANNNNNG!*

Dammit dude... that is what I call some proper "Morning Wood"! 

Do this things count as TEA purchase ? 

Resistance of 1K, 10 miliOhm and 1 miliohm shunts, with 0.1 % tolerance and TCR of 30-50 ppm/K.
Tempted by their nice resistance numbers.

As long as you use them to build test jigs, fo' sho' TEA in all it's glory.

These are a few of my own favorite eBay resistor searches:

1000W Braking resistor:

2000W braking Resistor:

Braking Resistor will return a lot of interesting high-wattage resistors, including lots of various aluminum shell modules in 5-50W range sold as ballast resistors to keep CANBUS cars from having a shitfit conniption about upgraded LED/HID lighting. They are crazy cheap in most cases, given the wattage/peso.

Win! Mine hasn't arrived yet

They're really good resistors. 50ppm tempco 1% 600mW.

I'm going to build an HF dummy load (6/12W undecided) with mine when they turn up. Need to work out a fun topology where they won't desolder themselves first

Pcb with 2 rails and then you'll have lots of air round them to help disapate the heat both soldering and in use?

That would be too easy. I've got some left over ring main flex which has proper thick copper in it. Figured I can build a rolled radiator pattern. I played with 3d topologies but you can't get an equal load across each of them which means hot spots and meltdowns.

Assuming I'm using 100 ohm resistors, of you have N resistors in series, that gives you a total R of N*100. Now to bring that down to 50 ohms you need (N*100)/50 of those in parallel.

So 5 resistors results in 10 bars of 5 resistors = 50 total = 30W.

Lets go mental: 10 resistors results in 20 bars of 10 resistors = 200 total = 120W.

Lets use ALL the 8000 resistors = 4.8KW 

SWR of that will probably be horrid though

I figure the SWR of anything you build with lots of film resistors is gonna be pretty horrible, unless you're operating down around Children's Band or Skipland. Otherwise, if you're just dealing with AF or DC, see above. A 1KW 1 ohm resistor will dissipate 4KW quite easily in a 5 gallon bucket of water for approx US$75, including the bucket. I know; I've done it. 


mnem
There is something seriously wrong with me...

[Cubdriver]

To get away from 20's era battery sets and back onto test gear, I finally got ambitious and got the Agilent 8644B that arrived from the 'bay around Christmas back up and running.  It had a shorted cap in one of the modules.
 

I realize that the modules are needed for shielding and ease of construction, and that capability-wise it blows the older gear out of the water, but it still looks kinda boring inside compared to the old stuff that's packed to the gills with visible circuit boards.

Still, nice to have it operational.  Thread on it here:
https://www.eevblog.com/forum/testgear/hpagilent-8644b-synthesized-signal-generator-bad-cap-repair/

-Pat

Actually, all that shielding and $20/foot cabling with $20 connectors on each end just screams "lots of electrons being tormented, molested and abused at very high frequency" to me. Turnabout is fair play, says I. 

It reminds me of pics I've seen of the equipment inside of 70s-80s vintage satellite gear and some of the stuff from various NASA missions I've seen.  i've always been a junkie for pics of the nuts & bolts of that kind of high-tech; doesn't matter to me if I understand how it works or even what the particular device does; I'm still just fascinated by it in the same way I am with high KW commercial broadcasting gear.

mnem
There is something seriously wrong with me...

Yes, the pixies apparently get really angry when you start shaking them back and forth at around a billion times a second, and really heroic measures are needed to keep them contained and at their work stations under such arduous conditions.  On top of the $$ cabling and SMC connectors, the bloody thing has 48 screws around the perimeter at the front of the case that had to be removed to get it nekkid.

Oh, and as for your little signature comment on this one - I'd venture that statement applies to all of us in this thread.  I personally could probably make a list for myself...   

-Pat

[mnementh]

Yeah, I peeked in on your repair thread and saw the before & after mayhem. 

I was thinking to myself "48 case screws by hand? F*** that noise!"

I'd go get the right bit or cut the handle off a screwdriver to chuck up in my drill/driver; I hate fighting screws by hand and my driver has the right clutch settings to make sure anything is torqued down properly. I've got a couple Makita 6019Ds I've kept alive for 20 years just to use as a driver; they're 2-speed so you can drill with them if you have to, nice & small to fit in your hand tools bag and light enough to use all day.

The reason I keep them is they have the perfect clutch for small electronics service; I can even set it low enough to drive m3 self-tappers back into plastic without stripping them. I've tried dozens of newer models and nothing has anything close to this near-perfect mix of features. I converted the packs to 2S2P 18650 power almost 10 years ago now.


mnem
*twizted*

[bd139]

I assembled an entire Ikea kitchen, living room and two bedrooms with a hand screwdriver over a weekend once. Bring it.

Spent two hours this afternoon assembling one of those cheap £3 fully discrete Chinese AM radio kits to play with.  Turns out the design is shit. The PA transistors are biased so badly they hit 70 oC in about 20 seconds from power up. I thought I’d screwed something up to start with but no, it’s just shit. Have added a 1n4148 to the bias chain and now can receive AM perfectly without it nearly going on fire.

So to debug a £3 radio I used about £1000 worth of test gear

Oh to make it complete I replaced all the 100 ohm resistors in it with TE LR1’s. 3 down 7997 to go 

Kit link https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F181871312895

Note if you buy one the instructions are in Chinese. Doesn’t matter. Just have to look up what colours are in Chinese for the IFTs.

[BravoV]

Do this things count as TEA purchase ? 

Resistance of 1K, 10 miliOhm and 1 miliohm shunts, with 0.1 % tolerance and TCR of 30-50 ppm/K.
Tempted by their nice resistance numbers.

As long as you use them to build test jigs, fo' sho' TEA in all it's glory.

These are a few of my own favorite eBay resistor searches:

1000W Braking resistor:

2000W braking Resistor:

Braking Resistor will return a lot of interesting high-wattage resistors, including lots of various aluminum shell modules in 5-50W range sold as ballast resistors to keep CANBUS cars from having a shitfit conniption about upgraded LED/HID lighting. They are crazy cheap in most cases, given the wattage/peso.

Does braking resistor need to be 0.1% tolerance, TCR 30 ppm/K and 4 wires sensing ? 

[Specmaster]

I assembled an entire Ikea kitchen, living room and two bedrooms with a hand screwdriver over a weekend once. Bring it.

Spent two hours this afternoon assembling one of those cheap £3 fully discrete Chinese AM radio kits to play with.  Turns out the design is shit. The PA transistors are biased so badly they hit 70 oC in about 20 seconds from power up. I thought I’d screwed something up to start with but no, it’s just shit. Have added a 1n4148 to the bias chain and now can receive AM perfectly without it nearly going on fire.

So to debug a £3 radio I used about £1000 worth of test gear

Oh to make it complete I replaced all the 100 ohm resistors in it with TE LR1’s. 3 down 7997 to go 

Kit link https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F181871312895

Note if you buy one the instructions are in Chinese. Doesn’t matter. Just have to look up what colours are in Chinese for the IFTs.

Ordering up another 2666 radio kits to use the remaining 100 ohm resistors then 

[mnementh]

I assembled an entire Ikea kitchen, living room and two bedrooms with a hand screwdriver over a weekend once. Bring it.

Spent two hours this afternoon assembling one of those cheap £3 fully discrete Chinese AM radio kits to play with.  Turns out the design is shit. The PA transistors are biased so badly they hit 70 oC in about 20 seconds from power up. I thought I’d screwed something up to start with but no, it’s just shit. Have added a 1n4148 to the bias chain and now can receive AM perfectly without it nearly going on fire.

So to debug a £3 radio I used about £1000 worth of test gear

Oh to make it complete I replaced all the 100 ohm resistors in it with TE LR1’s. 3 down 7997 to go 

Kit link https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F181871312895

Note if you buy one the instructions are in Chinese. Doesn’t matter. Just have to look up what colours are in Chinese for the IFTs.

I've disassembled whole vehicles with hand tools, then put them back together the same way. I'm no stranger to doing it the hard way; I just feel my time has some value, so I refuse to waste my most precious commodity. You know, aside from manipulating buttons on my desk to inconvenience lots of electrons so they organize themselves into serial data as output to the internet. 

Nothing gives you the warm fuzzies about a transaction like paying to be somebody else's ßeta tester, eh?   

It's pretty much a fact of life in the RC Hobbyist sector... especially when it comes to ESCs, flight controllers and their firmware, which run on approximately a 6-18 month obsolescence cycle. 

So I guess the question that pertains is... were you able to successfully mod it to the broader frequency range as you were talking about earlier?   

Do this things count as TEA purchase ? 

Resistance of 1K, 10 miliOhm and 1 miliohm shunts, with 0.1 % tolerance and TCR of 30-50 ppm/K.
Tempted by their nice resistance numbers.

As long as you use them to build test jigs, fo' sho' TEA in all it's glory.

These are a few of my own favorite eBay resistor searches:

1000W Braking resistor:

2000W braking Resistor:

Braking Resistor will return a lot of interesting high-wattage resistors, including lots of various aluminum shell modules in 5-50W range sold as ballast resistors to keep CANBUS cars from having a shitfit conniption about upgraded LED/HID lighting. They are crazy cheap in most cases, given the wattage/peso.

Does braking resistor need to be 0.1% tolerance, TCR 30 ppm/K and 4 wires sensing ? 

No, but you didn't say your application NEEDED them to be either.

I was just passing on what i considered to be a "find" in similar vein; not that they would be applicable in every case yours would be. 


mnem
Made you look.