Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

bloody hell. Hubby in hospital with heart issues. Undergoing angio right now.

Why does my life always kick me in my nonexistent balls ? 

First, all the best.

Second, having yourself examined ASAP in case of heart problems is the only intelligent thing to do.
German heart medicine is quite good, I had the same thing, got 3 bypasses and they fixed me good enough that I got a pilot license afterwards
(admittedly after some physical exercise before the exam).

Third, there is no plan B. Life kicks, wether you got balls or not. The good die young, the smart ones can survive a bit longer if they take care.
Choose your side.

*Casts a prayer to Ifni for friends and extended family*

This sums up everything I was feeling on reading this; been mulling over my own mortality after my recent birthday followed by trying to get to sleep last night without my CPAP because power went out til 1am. Thanks for summing it up better than I can right now. 

1 additional stent, ICU ...

Everything Wolfgang said above... and sincere hopes that this time in the hospital buys you both a lot more time together.

mnem
May serenity find you, my friend.

[tggzzz]

You mean this kind of copper foil?
https://www.ebay.com/itm/373014859528

There are many examples of copper foil.

Those marketed for electronic purposes will have a slightly conductive adhesive, since the foil is typically used reduce EMI by covering gaps in cases.

Those marketed for other purposes are unlikely to care (or specify!) whether the adhesive is conductive.

[Cerebus]

I would have guessed 500 ...
if what you have is working, why upgrade ?

The person first uttering a price is loser in any negotiation.

Ooh no. Back in my ISP days we did a lot of turnkey jobs, so I got quite a lot of experience of haggling resale discounts and the like. That is, I got a lot of experience until we got big enough where I could turn this job over to one of my staff; in this case young Andy, who I gave 1/2 a day's training by letting him sit on on phone calls where I negotiated prices with suppliers. I was fairly au fait with what discounts would be reasonable and I'd open the bidding at 25% of list price if I thought that 33% would be reasonable, 40% if I thought I might eventually get 50% and so on. Little did I know what I was unleashing on the world, Andy was a shark and moreover loved doing it. Poor suppliers didn't know what had hit them. Best thing i ever did handing that job off to him - he shaved 10% to 20% off our bought-in costs in a few months.

Anyway, the only time I 'lost' when being the first person to utter a price was negotiating our reseller discount with a Cisco distributor. Cisco and their distributors were known to be hard to get resale discounts out of. I knew that the discount that the distributor were likely to be getting themselves from Cisco was 50% and I would have counted myself lucky to to get a 30% discount. So, just for a laugh, my opening bit was 50% "based on such-and-such a volume in the next year". "OK." "Sorry what was that?" "OK, 50%." I'd just got 50% discount on my opening bid. Don't get me wrong, that was a great discount for Cisco kit, but the immediate "OK" tells me that if I'd played harder I'd have got perhaps another 5%, but the game was already over and trying to haggle further would have been a risky strategy.

So, moral of the story. If you are the first out of the gate you're the one who sets expectations for a negotiation. The final result is likely to settle between what you say and the next psychologically 'round' figure up or down from where you started (depending on whether you're buying or selling respectively). If you let the other guy speak first he gets to set that range, not you. So you're best off being the first to put a number out there. Military analogy, it's better if you get to pick the battlefield, not the other side.

[med6753]

Under any circumstances, I've contrived a bodge that gets the old RIFA back in circuit mostly safely so I could put the scope back to standby duty instead of the repair queue; no, I'm not going to post pics of that crime.    Just know that I've admitted my guilt here and now; if Karma catches up with me, I can greet Murphy with a clear conscience. 

mnem
 

  I share my bodges for the entire group to criticize and laugh at. What makes you special? 

   Because it's WORSE than this one, which, thankfully, did NOT fit in place. 

mnem
 

That is perfectly acceptable, I have seen many new pieces of gear with parts mounted beneath the board.

In this case it produces potential capacitive coupling (and arcing potential) between:

1) Gate of main 1st DC converter FET switching ~300V
2) Source of same FET (Also connected to heat sink and LO Potential side of rectified AC line voltage)
3) Low Voltage "GND" plane fill under corner of capacitor which is supposed to be completely isolated from Line Voltage side of SMPS
4) Metal chassis at AC LINE GND which this all faces at  ~6mm spacing

I tried to salve my conscience with 3 layers of Kapton tape wrapped around it all but honestly; it really is probably for the best that it wouldn't physically fit that way.

mnem
 

first the dragon admits to a bodge. 

then he refused to show it.

next he shows an attempted bodge that did not stay in place only because it did not fit.

then he presents multiple reasons that his bodge is a bad idea.

finally he offers kapton tape as a mitigation method.

how often does he hear the voices?  how does he decide which one wins the argument?  are some louder than the others? 


so......is the scope reassembled and working?   as proof you could at minimum post a pic of the hidden tetris game.  (my 54601 has one)

[Cerebus]

bloody hell.

Hubby in hospital with heart issues. Undergoing angio right now.

Why does my life always kick me in my nonexistent balls ? 

You do seem to be having "a bit of a year".

Good luck, and give the old man all our best wishes.

[mnementh]

Running a wire for high current traces is kind of risky I think.

It's not that I would not do it if I had to revive something and did not have any other choice.

However for some applications I would rather cut out an entire new trace and attach it to the board and exchange the rivets connecting top and bottom layer (I have a Bungard press for this).

Which is why I was asking for the self adhesive copper foil.

It seems to me that 3m conductive copper foil would be an option, however a friend of mine will send me some to repair my preamp.

Procedure is:
remove Solder mask, cut to fit, put on, tin it, check continuity, reapply solder mask

obviously the pcb needs to be inspected for cracks and damaged traces, and that is where the microscope comes in.

Another option is copper foil made for Tiffany-technique (Yes THAT Tiffany's) stained glass art. It has a heat-activated epoxy coating (if you get the good stuff, not the cheap shit from GoodLuckBuy) on the back that is meant to bond with glass; it works equally well on FR4, etc. It is available in widths from 3mm to 14mm last time I looked. I have used this to make PCBs from scratch. Available from any reputable stained-glass supply house for pretty reasonable.

mnem
 

You mean this kind of copper foil?      https://www.ebay.com/itm/373014859528

Yes, but get the kind with copper finish both sides or pretinned, not the stuff with black coating. Part of the Tiffany technique is washing the finished piece with a (IIRC) hydrated copper sulphate solution to give both copper and solder the characteristic black Tiffany's patina. This tape has one side already patina'd. Obviously, for electronics work that is NOT a good choice.

The best way to be sure is to contact your vendor beforehand; if they actually do Tiffany-technique stained glass, they'll be able to tell you if the foil they sell has the adhesive coating.

In case you didn't guess, I've done this kind of stained glass work with my mother; in fact, I still have about 6 huge totes full of her old workbench in my storage. One of these days I'll get back into it; the ache has faded and I think maybe I can enjoy doing it again.

mnem
*sigh*

[mnementh]

I would have guessed 500 ...
if what you have is working, why upgrade ?

The person first uttering a price is loser in any negotiation.

Ooh no. Back in my ISP days we did a lot of turnkey jobs, so I got quite a lot of experience of haggling resale discounts and the like. That is, I got a lot of experience until we got big enough where I could turn this job over to one of my staff; in this case young Andy, who I gave 1/2 a day's training by letting him sit on on phone calls where I negotiated prices with suppliers. I was fairly au fait with what discounts would be reasonable and I'd open the bidding at 25% of list price if I thought that 33% would be reasonable, 40% if I thought I might eventually get 50% and so on. Little did I know what I was unleashing on the world, Andy was a shark and moreover loved doing it. Poor suppliers didn't know what had hit them. Best thing i ever did handing that job off to him - he shaved 10% to 20% off our bought-in costs in a few months.

Anyway, the only time I 'lost' when being the first person to utter a price was negotiating our reseller discount with a Cisco distributor. Cisco and their distributors were known to be hard to get resale discounts out of. I knew that the discount that the distributor were likely to be getting themselves from Cisco was 50% and I would have counted myself lucky to to get a 30% discount. So, just for a laugh, my opening bit was 50% "based on such-and-such a volume in the next year". "OK." "Sorry what was that?" "OK, 50%." I'd just got 50% discount on my opening bid. Don't get me wrong, that was a great discount for Cisco kit, but the immediate "OK" tells me that if I'd played harder I'd have got perhaps another 5%, but the game was already over and trying to haggle further would have been a risky strategy.

So, moral of the story. If you are the first out of the gate you're the one who sets expectations for a negotiation. The final result is likely to settle between what you say and the next psychologically 'round' figure up or down from where you started (depending on whether you're buying or selling respectively). If you let the other guy speak first he gets to set that range, not you. So you're best off being the first to put a number out there. Military analogy, it's better if you get to pick the battlefield, not the other side.

"Maxim 47. Don't expect the enemy to cooperate in the creation of your dream engagement." 

mnem
"Nobody ever won an argument with a customer."

[Cerebus]

Another option is copper foil made for Tiffany-technique (Yes THAT Tiffany's) stained glass art. It has a heat-activated epoxy coating (if you get the good stuff, not the cheap shit from GoodLuckBuy) on the back that is meant to bond with glass; it works equally well on FR4, etc. It is available in widths from 3mm to 14mm last time I looked. I have used this to make PCBs from scratch. Available from any reputable stained-glass supply house for pretty reasonable.

mnem
 

That's worth knowing about.

I've worked with high performance epoxy pre-preg before, and that stuff is delivered by a 'cold chain'. The distributor keeps in a fridge, it's delivered on refrigerated transport, and you keep it in the fridge/freezer until you're ready to actually use it. Heat cure epoxy can be formulated to have passable room temperature storage qualities, but it's always going to be a trade-off of ultimate performance versus storage tolerance. I'd imagine that's why stuff from the "bang good happy luck club" isn't any kop, it's distributed with no environmental control at all so that it might have been great initially but by the time you get to use it, it has used up all its shelf life.

[tonyalbus]

I sold a Tek AWG2021 in a parking lot yesterday. I interestingly felt like a dealer.

Imagine the empty parking lot of a shopping mall. I'm outside my car checking my phone. The client arrive and park his BMW nearby. I open the trunk of my car. He inspects the goods then satisfied, pay me cash.

Yeah, I felt the same! The AWG works great BTW. The fun part will be to build a GPIB controller interface now.
Thanks! 

Welcome to this stange club mabehem!
we allready made you a junkie, or atleast feel like one 

[mnementh]

You mean this kind of copper foil?
https://www.ebay.com/itm/373014859528

There are many examples of copper foil.

Those marketed for electronic purposes will have a slightly conductive adhesive, since the foil is typically used reduce EMI by covering gaps in cases. Those marketed for other purposes are unlikely to care (or specify!) whether the adhesive is conductive.

Different stuff altogether; it has a press-apply adhesive. Most cases that kind of foil made for shielding is NOT meant to be soldered to, except to attach a pigtail or somesuch to the non-adhesive side. The adhesive is intended to stay flexible and conductive but soldering heat will melt it or burn it away right under the solder point.

There is a variant made for doing PCB traces; it is typically frightfully expensive (because they know what you're doing with it) and is usually sold by the INCH. It also has a heat-cured adhesive, which IME bonds no better than (and may be exactly the same product, only relabeled) that made for Tiffany-technique stained glass.

mnem
 

[Saskia]

found https://www.ebay.com/itm/MPJ-34181MI-5mm-0-2-COPPER-FOIL-PRINTED-CIRCUIT-BOARD-PCB-REPAIR-TAPE-/152874416528
seems to be an option ...
at least this is mentioned in some repair vids.

[Saskia]

@Cerebus the only time I have lost a negotiation so far was when I was absent due to illness and my boss decided to take over. He decided that I was too aggressive and that cost me my negotiating advantage with the vendor.

Now it is up to him to haggle with this particular vendor.
Normally negotiations over here are the job of the purchasing department and I'll gladly leave it to them, however they from time to time delegate it back to me.

Sometimes this is getting painful, as their expectations do not meet up with my notion of live and let live.

[nixiefreqq]

Under any circumstances, I've contrived a bodge that gets the old RIFA back in circuit mostly safely so I could put the scope back to standby duty instead of the repair queue; no, I'm not going to post pics of that crime.    Just know that I've admitted my guilt here and now; if Karma catches up with me, I can greet Murphy with a clear conscience. 

mnem
 

  I share my bodges for the entire group to criticize and laugh at. What makes you special? 

   Because it's WORSE than this one, which, thankfully, did NOT fit in place. 

mnem
 

That is perfectly acceptable, I have seen many new pieces of gear with parts mounted beneath the board.

In this case it produces potential capacitive coupling (and arcing potential) between:

1) Gate of main 1st DC converter FET switching ~300V
2) Source of same FET (Also connected to heat sink and LO Potential side of rectified AC line voltage)
3) Low Voltage "GND" plane fill under corner of capacitor which is supposed to be completely isolated from Line Voltage side of SMPS
4) Metal chassis at AC LINE GND which this all faces at  ~6mm spacing

I tried to salve my conscience with 3 layers of Kapton tape wrapped around it all but honestly; it really is probably for the best that it wouldn't physically fit that way.

mnem
 

first the dragon admits to a bodge. 

then he refused to show it.

next he shows an attempted bodge that did not stay in place only because it did not fit.

then he presents multiple reasons that his bodge is a bad idea.

finally he offers kapton tape as a mitigation method.

how often does he hear the voices?  how does he decide which one wins the argument?  are some louder than the others? 


so......is the scope reassembled and working?   as proof you could at minimum post a pic of the hidden tetris game.  (my 54601 has one)

well i really wanted to see the bodge that stayed in.

med tried the direct approach and failed.

figured that a diversion might provoke a result.

BUT.....it looks like the dragon is listening to the voice that read the counterinsurgency field manual.  (or maybe the voice that read sun tzu)

[mnementh]

Another option is copper foil made for Tiffany-technique (Yes THAT Tiffany's) stained glass art. It has a heat-activated epoxy coating (if you get the good stuff, not the cheap shit from GoodLuckBuy) on the back that is meant to bond with glass; it works equally well on FR4, etc. It is available in widths from 3mm to 14mm last time I looked. I have used this to make PCBs from scratch. Available from any reputable stained-glass supply house for pretty reasonable.

mnem
 

That's worth knowing about.

I've worked with high performance epoxy pre-preg before, and that stuff is delivered by a 'cold chain'. The distributor keeps in a fridge, it's delivered on refrigerated transport, and you keep it in the fridge/freezer until you're ready to actually use it. Heat cure epoxy can be formulated to have passable room temperature storage qualities, but it's always going to be a trade-off of ultimate performance versus storage tolerance. I'd imagine that's why stuff from the "bang good happy luck club" isn't any kop, it's distributed with no environmental control at all so that it might have been great initially but by the time you get to use it, it has used up all its shelf life.

Well, there you have more experience than I do for sure.    I've used those frightfully expensive trace repair kits (the ones with little strips of copper, round dots for pads, and some even have parts to make vias) and while I vaguely recall one of them suggesting in the destructions to keep in a fridge for longest life, they certainly did not come shipped in any kind of Cryo-Pak; just a little plastic box full of bits & pieces.

Based on that experience and my experience with the Tiffany process, my surmise (as in my post above) was that functionally there was little difference. The stuff bonds pretty well, but certainly can be peeled up if you try to or if you overheat it. I would guess that Tiffany's foil was coated with an organic epoxy based on the time period in which he developed the process; no idea if that is still the case with modern equivalents.

As a similar case study; look at the evolution of solder-wick and solder itself; both of which (in mass-production) have been greatly transformed by the halogenated fluxes commonly used with lead-free solder.  Not only has lead-free solder become the norm; now even if you want to work with leaded solder what you can get is usually 63/37 hypereutectic alloy with the same halogenated flux as used in lead-free. This makes even a nice, properly-wetted solder joint harden ugly dull-grey and bubbly half the time.

Proper rosin core 60/40 is now a luxury item; generally considered to be little more than an affectation of us old farts who won't give up our dain bramage.   

mnem
 

[Cerebus]

So, a few weeks back I was trolling through eBay, as you do, and one of my searches tripped across a supplier in the West Country who clearly handled a lot of military surplus and had bad spelling. Bingo! So I went through the 'show all items' listing for them looking to see if I could find some gems. No luck unfortunately, but I did trip over one item that piqued my curiosity.

They had a job lot of sheets of expanded aluminium honeycomb hex-core in all sorts of sizes. Thousands of pounds worth if you had a use for it or could intelligently resell it and they were asking £500. As I often do I marked it for my watch list, just to see what happened. No bids, relisted for a bit less. Ditto. Ditto. And today it's still unsold with a £300 opening price.

An aside. For those who don't know the stuff, this is aluminium foil carefully glued and pulled out into hexagonal form. You may have seen the same thing done with paper to make a strong, highly energy absorbing packing material. You can sandwich this 'hex-core' with glue between a couple of sheets of some skinning material and make very light panels that have incredible strength and stiffness for their weight. Think really thick corrugated cardboard technology applied to metal but with the corrugations going 'in' instead of 'along'. Nowadays the army uses this stuff to build Bailey bridges that you can literally drive a tank over, but the panels are light enough to be moved and installed by hand.

So, on the second or third pass on the aluminium hex-core I spotted that they had listed separately a single panel (8' x 4', 2.5m x 1.25m, cut into two half panels for delivery) of 25mm thick hex-core made with phenolic bonded Kevlar 'paper' listed for £30 plus £10 postage - with a, not unrealistic, indication that the original cost of the panel was £225. Again out of curiosity, 'watched' to see what would happen.

So, you can guess what happened. Eventually the opening bit went down to £10 and that imp that says "that's so cheap, you're bound to find a use for it" took over and long story short, I'm trying to find somewhere sensible to keep two 1.25m square pieces of 25mm thick Kevlar honeycomb and SWMBO is giving me funny looks.

[Saskia]

ok, issue solved. my mentor will mail me some copper foil to fix the preamp traces that are presumable dead.

As for why I don't like wires:

does not look like new
may interfere with mounting
may interfere with connectors (on a pinball powerboard you have Molex connectors sitting on top of those traces. You may have a hard time running a wire, and apart from that in most cases this does not look like a professional repair. Can show photos.

I do use some enamel wires if the diameter/width of the trace is too small. if I have to run a wire to a 0.1 mm pitch SMD thingie there is no way I can accomplish that with some adhesive copper foil. That's where the 0.05 mm wire comes into play.

Update: 24 hours monitoring in ICU. will know tomorrow what the score is wrt Hubby. Nothing that can be done, and I cannot visit him due to covid.

As a side note, I can scratch our boating vacation, as I am unable to handle the RIB on land single handedly (it's a 21" cat B RIB with an underpowered outboard of 115 bhp for up to 8 bft and 4m wave height), I could handle it in the water, but slipping it single handedly is a no go.

I am particularly unhappy right now.

[Cerebus]

Based on that experience and my experience with the Tiffany process, my surmise (as in my post above) was that functionally there was little difference. The stuff bonds pretty well, but certainly can be peeled up if you try to or if you overheat it. I would guess that Tiffany's foil was coated with an organic epoxy based on the time period in which he developed the process; no idea if that is still the case with modern equivalents.

You piqued my curiosity; I went on a hunt. Apparently the original Tiffany process involved wrapping copper foil around the edges of each piece of glass, assembling them all with temporary tacks in a wooden mould and lead soldering the backside of the abutting copper foils together in a way that the lead didn't show on the outside. Then it was all patinated, further hiding the lead soldering.

[tggzzz]

I am particularly unhappy right now.

I have low expectations for the next year.

I have told my daughter thant I will regard it as a success if we are both alive in a years time.

[Robert763]

Seems I was the only bidder on a 40W Nd-YAG laser system on ebay.
99p The cases are worth a lot more that
www.ebay.co.uk/itm/224106676433

Not sure if there are scanners included.

[bd139]

I am particularly unhappy right now.

I have low expectations for the next year.

I have told my daughter thant I will regard it as a success if we are both alive in a years time.

I’m in an Ikea queue. I am happy if I survive the next hour

[mnementh]

Under any circumstances, I've contrived a bodge that gets the old RIFA back in circuit mostly safely so I could put the scope back to standby duty instead of the repair queue; no, I'm not going to post pics of that crime.    Just know that I've admitted my guilt here and now; if Karma catches up with me, I can greet Murphy with a clear conscience. 

mnem
 

  I share my bodges for the entire group to criticize and laugh at. What makes you special? 

   Because it's WORSE than this one, which, thankfully, did NOT fit in place. 

mnem
 

That is perfectly acceptable, I have seen many new pieces of gear with parts mounted beneath the board.

In this case it produces potential capacitive coupling (and arcing potential) between:

1) Gate of main 1st DC converter FET switching ~300V
2) Source of same FET (Also connected to heat sink and LO Potential side of rectified AC line voltage)
3) Low Voltage "GND" plane fill under corner of capacitor which is supposed to be completely isolated from Line Voltage side of SMPS
4) Metal chassis at AC LINE GND which this all faces at  ~6mm spacing

I tried to salve my conscience with 3 layers of Kapton tape wrapped around it all but honestly; it really is probably for the best that it wouldn't physically fit that way.

mnem
 

first the dragon admits to a bodge.  then he refused to show it.   next he shows an attempted bodge that did not stay in place only because it did not fit.   then he presents multiple reasons that his bodge is a bad idea.   finally he offers kapton tape as a mitigation method.   how often does he hear the voices?  how does he decide which one wins the argument?  are some louder than the others? 

so......is the scope reassembled and working?   as proof you could at minimum post a pic of the hidden tetris game.  (my 54601 has one)

Oh sweet cheese and crackers. 



Here... is this proof enough...? This is the only EasterEgg I've found on the 54645A; discovered by pressing Print/Utility then underscreen button 3/4. 2/3 as used for the Tetris EasterEgg just returns "That button is not used in this menu." My guess is not enough ROM space with the deep memory models...?

mnem

[Cerebus]

I am particularly unhappy right now.

I have low expectations for the next year.

I have told my daughter thant I will regard it as a success if we are both alive in a years time.

I’m in an Ikea queue. I am happy if I survive the next hour

And possibly happier if someone accedes to your wish of "kill me now". 

[mnementh]

I sold a Tek AWG2021 in a parking lot yesterday. I interestingly felt like a dealer.

Imagine the empty parking lot of a shopping mall. I'm outside my car checking my phone. The client arrive and park his BMW nearby. I open the trunk of my car. He inspects the goods then satisfied, pay me cash.

Yeah, I felt the same! The AWG works great BTW. The fun part will be to build a GPIB controller interface now.
Thanks! 

Welcome to this stange club mabehem!
we allready made you a junkie, or atleast feel like one 

Welcome to a fellow Canuck! (Okay; I'm a wannabe Canuck, but we still haven't given up on the dream) There's the Neverending Taco Truck in the corner, beanflying is AWOL IRL ATM, but his coffee bar pretty much runs on autopilot (his secrets guard themselves) and the crusty old Aardvark in the corner is mostly harmless, unless you see him with his conversational cutlery. Watch out for the attitudinally maladjusted smurf running around with a can of blue spray paint tho... unless you fancy a change of your personal scenery. 

Just be aware that the pervy little dwagon fancier position is already taken; get your own schtick. 

mnem

[Zucca]

1 additional stent, ICU ...

My old dad (production year 1945) got 2 stents 11 years ago, he is still smiling and kicking.
There is no storm which will last forever, meanwhile I pray for you and your family.

[bd139]

I am particularly unhappy right now.

I have low expectations for the next year.

I have told my daughter thant I will regard it as a success if we are both alive in a years time.

I’m in an Ikea queue. I am happy if I survive the next hour

And possibly happier if someone accedes to your wish of "kill me now". 

Well I survived. The rainbow crap drawers which are slowly being crushed by the HP stack are going finally.