Test Equipment Anonymous (TEA) group therapy thread

[mansaxel]

People are fucking crazy. A 3478a in good condition went for close to 400 money locally. I gave it up when it went past 200 money, and concluded I might as well buy one from overseas.

[bd139]

400 sek or quid or dollars or dollarydoos? 

[med6753]

.....snip

But is wasn't a bench meter and it is a mere 1999 count.  So I bought a Digimess DM200 from their eBay store.  This solid 4000 count meter is a rebranded Mastech. 


.....snip

It sure is.



And welcome to our group of misfits. 

[med6753]

Well the hospital just called and I have to be there at 0545 hours tomorrow morning. I guess I'm first on the list which I suppose is good because the doctor will be nice and fresh....or hung over.  Was told the operation would take approx 1.5 hours. My son will pick me up at 0500 hours.

Thanks for all your encouragement. I just want to get this over with and move on. 

[mnementh]

Good to hear it's going well, med. Good luck and godspeed. 

mnem
 

[25 CPS]

Well the hospital just called and I have to be there at 0545 hours tomorrow morning. I guess I'm first on the list which I suppose is good because the doctor will be nice and fresh....or hung over.  Was told the operation would take approx 1.5 hours. My son will pick me up at 0500 hours.

Thanks for all your encouragement. I just want to get this over with and move on. 

I hear you.  I remember the drive to the hospital for my last hernia, looking out the car window watching the scenery going by trying to distract myself and dreading the whole thing, just wanting it to be over, too.  I hope everything goes well tomorrow and you have a speedy recover after.  Let us know you're ok as soon as you're able to.

[mnementh]

This got all mixed up due to me trying to finish it in the car on my tablet, so I'm gonna make it a new post here. Oi.

   

Ughhh... Pioneer is killing me. First, the whole gawddamn thing is cheapest possible single-sided paxolin PCBs with edge connectors stacked together like a gingerbread house; I spent a whole afternoon dismantling, inspecting and reassembling the stoopit thing to eliminate that very obvious point of failure. And yes, all rigid assembly; not even sense enough to use FPC interconnects because they'd cost 50c more per unit.

  mode on:

I swear, for the last 20 years, Pioneer just goes from one colossally shite design flaw to the next. Anybody here remember the wind-tunnel of doom with all the power semis in a PCB box that would go critical meltdown when the fan croaked or even slowed down due to dry bushings? This design may be worse... and it's not like they didn't know it is a major fault mode; checking all the PCB connectors is literally the first step in their diag process.

  mode off:



Anyways... Now that assache is done and eliminated as a culprit, I've traced out the STBY switch and relay all the way back to the CPU, and while it does pull the correct pin LO when I press the button, no signal from the CPU on the relay pin even after confirming all Vccs, AVccs and reference voltages present. I checked for the obvious pitfalls; no WAIT or RESET pin being held LO (as per the chip datasheet), but I did discover no oscillator at X201.



Suspecting a fauty crystal, I swapped it into an old USB-ASP I had lying around, and it came up with a nice clean signal right at 16mhz & 500mv p-p. I then tried replacing those two 22puff caps in the oscillator; but all I have on hand is 1puff and 100puff SMDs. I tried with the 1puff caps and it would oscillate for aboot 4 seconds every power-up; good clean signal just like above with the USB-ASP.

After that, I spent an afternoon harvesting random MLCCs from several PCBs; I gave that BELKIN infested-with-spyware-from-the-factory NAS main board the ignominious demise it so justly deserves. 

Sadly, I did not find a single 22puff cap after a good 2 hours sorting with my MS8911; everything I found (even teeny tiny little 0402 bastards) was either way higher or way lower value. Out of frustration, I tried it with the caps removed altogether, and now it does oscillate for a good 30 seconds at a time, but the waveform is a bit distorted due to the DC bias across the crystal, tho it is stable at a solid 16Mhz and again, 500mv p-p. Still no reaction to pulling the STBY switch input pin LO, though.

This did give an opportunity to do some further diag, however... And even tho I can see it oscillating at X201, I can't find any signal at any of the clock output pins. *sigh*

Right now I'm trying to lay my hands on a proper 0602 cap sample book at a sane price somewhere reasonably quick delivery; I really need it in my stockpiles anyways. Given the lack of any heartbeat 💓 from any pin on the CPU I have little hope of it bringing the thing back to life, but hey; it at least gives me something else to think aboot for a while.

mnem
 

[bd139]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

[factory]

Lucky you are into Tek scopes then and wouldn't have any interest in a $100 hernia busting Curve tracer  Jump on it quick someone.... eBay auction: #402956962238

Local pickup only in Carson City, Nevada.

In better times ROAD TRIP  With the collection of glass inside it I would think pickup a good idea regardless. Still very cheap even in that condition.

Same seller has an Interesting lot of Test gear with some up for delivery too https://www.ebay.com/sch/Business-Industrial/12576/m.html?item=402956962238&ViewItem=&_ssn=capitolcityloans

Here is something I got from that seller in March, unfortunately they decided a cut down box with half a UPS envelope stuck in front and that loose-ish inside a bigger box was sufficient to send it overseas. 



It ended up with the front panel bashed in, the plastic meter casing completely destroyed and neon indicator broken.



I can't complain too much as I did get a prompt refund. I've since spent a fair bit of time repairing the damage and replaced both halves of the meter casing with the last spares I had.




David

[Andrew_Debbie]

I’d buy that aneng DMM with the BT and clock if it had a coffee pot on it too

It can't make coffee but it can charge 18650 batteries 

[bd139]

Lucky you are into Tek scopes then and wouldn't have any interest in a $100 hernia busting Curve tracer  Jump on it quick someone.... eBay auction: #402956962238

Local pickup only in Carson City, Nevada.

In better times ROAD TRIP  With the collection of glass inside it I would think pickup a good idea regardless. Still very cheap even in that condition.

Same seller has an Interesting lot of Test gear with some up for delivery too https://www.ebay.com/sch/Business-Industrial/12576/m.html?item=402956962238&ViewItem=&_ssn=capitolcityloans

Here is something I got from that seller in March, unfortunately they decided a cut down box with half a UPS envelope stuck in front and that loose-ish inside a bigger box was sufficient to send it overseas. 



It ended up with the front panel bashed in, the plastic meter casing completely destroyed and neon indicator broken.



I can't complain too much as I did get a prompt refund. I've since spent a fair bit of time repairing the damage and replaced both halves of the meter casing with the last spares I had.




David

Oh that sucks. Anyone who packs stuff like that should be placed inside a large cardboard box with no padding and shipped somewhere via Hermes.

[bd139]

I’d buy that aneng DMM with the BT and clock if it had a coffee pot on it too

It can't make coffee but it can charge 18650 batteries 

That’s actually quite impressive 

[Andrew_Debbie]

Well the hospital just called and I have to be there at 0545 hours tomorrow morning. I guess I'm first on the list which I suppose is good because the doctor will be nice and fresh....or hung over.  Was told the operation would take approx 1.5 hours. My son will pick me up at 0500 hours.

I had my repair January 11 after a year long wait due to Covid. 

It hurt something awful for several days but I'm much better now.

 

[mnementh]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

Yeah, I know... but I was just looking for signs of life there. Considering capacitive loading, I've tried probing with and without a monitor on pin 15. As I know I'm able to get a consistent 30-ish seconds of oscillation with it right now, pretty sure that probing one or two output pins immediately after power cycling the thing, then moving on to the next, etc... the lack or presence of a signal is still valid data. If not, then replacing those 22puff caps should put the point to rest.

Also, I tried the 12MHz cap from the USB-ASP with similar behavior; sadly, still no 💓 output from any other pin.

I've shopped some 16MHz crystals, but all that's readily available is 20pF versions commonly used with Ardu; I might make that attempt after I track down some 22puff 0602 caps.

mnem
 

[mnementh]

I’d buy that aneng DMM with the BT and clock if it had a coffee pot on it too

It can't make coffee but it can charge 18650 batteries 

That’s actually quite impressive 

That's actually what this gets used for more often than anything else... 

mnem
*tzzzt*

[factory]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

I don't know about crystals wearing out, but have certainly come across shattered ones in stuff at work.

David

[Specmaster]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

Yeah, I know... but I was just looking for signs of life there. Considering capacitive loading, I've tried probing with and without a monitor on pin 15. As I know I'm able to get a consistent 30-ish seconds of oscillation with it right now, pretty sure that probing one or two output pins immediately after power cycling the thing, then moving on to the next, etc... the lack or presence of a signal is still valid data. If not, then replacing those 22puff caps should put the point to rest.

Also, I tried the 12MHz cap from the USB-ASP with similar behavior; sadly, still no 💓 output from any other pin.

I've shopped some 16MHz crystals, but all that's readily available is 20pF versions commonly used with Ardu; I might make that attempt after I track down some 22puff 0602 caps.

mnem
 

Is it not possible to provide a 16MHz signal via your signal generator to test it with?

[factory]

Lucky you are into Tek scopes then and wouldn't have any interest in a $100 hernia busting Curve tracer  Jump on it quick someone.... eBay auction: #402956962238

Local pickup only in Carson City, Nevada.

In better times ROAD TRIP  With the collection of glass inside it I would think pickup a good idea regardless. Still very cheap even in that condition.

Same seller has an Interesting lot of Test gear with some up for delivery too https://www.ebay.com/sch/Business-Industrial/12576/m.html?item=402956962238&ViewItem=&_ssn=capitolcityloans

Here is something I got from that seller in March, unfortunately they decided a cut down box with half a UPS envelope stuck in front and that loose-ish inside a bigger box was sufficient to send it overseas. 


It ended up with the front panel bashed in, the plastic meter casing completely destroyed and neon indicator broken.


I can't complain too much as I did get a prompt refund. I've since spent a fair bit of time repairing the damage and replaced both halves of the meter casing with the last spares I had.


David

Oh that sucks. Anyone who packs stuff like that should be placed inside a large cardboard box with no padding and shipped somewhere via Hermes.

In this area Parcelforce would be a better choice for that, earlier in the year I was waiting in the car near a local chippy and watched the guy sorting parcels in the back of the van, by throwing them around & dropping them. 
Also had a delivery where they didn't ring the doorbell, but we did hear the thud the parcel made, that they dropped by the door. 
Hope that guy has either quit or been fired by now.

David

[mansaxel]

400 sek or quid or dollars or dollarydoos? 

Euro.

Today, one Euro is 10,14 SEK, and one USD is 8,54 SEK. The pound is slightly above the Euro at 11,83 SEK.

[bd139]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

I don't know about crystals wearing out, but have certainly come across shattered ones in stuff at work.

David

That’s just extremely rapid wearing out  .I’ve seen some of them get dicky after a few years. I’ve mostly destroyed them past forensic analysis trying to find out why exactly. I had one Racal OCXO Crystal drift so far out of tolerance it was useless.

400 sek or quid or dollars or dollarydoos? 

Euro.

Today, one Euro is 10,14 SEK, and one USD is 8,54 SEK. The pound is slightly above the Euro at 11,83 SEK.

Oh wow that’s insane then !

[mansaxel]

Well the hospital just called and I have to be there at 0545 hours tomorrow morning. I guess I'm first on the list which I suppose is good because the doctor will be nice and fresh....or hung over.  Was told the operation would take approx 1.5 hours. My son will pick me up at 0500 hours.

Thanks for all your encouragement. I just want to get this over with and move on. 

Good luck! And happy birthday! (I know I wrote that already, last week, but one early and one late congratulation average out as being on the right day!)

[kleiner Rainer]

Another repair finished. My first oscilloscope, a Voltcraft 2040 made in 1987, developed a fault in channel 2: the Y-channel adjustment had a very restricted range, and signals fed into channel 2 showed also up in channel 1.  After studying the schematic (came with the scope manual!) I checked the channel switching/chopping unit with my THS720 - one of the cases where you need more than one scope. The culprit was soon found: one output of the 4013 toggle FF was stuck High, so channel 2 was always on.

The only problem was that the bottom of the vertical amp could not be reached to remove the defective chip and put in a socket without dismantling everything in the scope. So I got out the scalpel and scored the pins of the 4013 directly at the package until the carcass of the chip could be removed.

Then I soldered the socket to the remaining pins from the top.

After plugging in a new 4013 and powering the scope up, it worked again. Some adjustment of the horizontal sweep was necessary, but not by much. The picture shows the component tester with a 6.2V zener connected.

The tube was made by Toshiba and is still in very good condition, as is the rest of the scope. Original Manufacturer was Sampo.

Greetings,

Rainer

[Vince]

I am very smart, really very smart.

When I moved house, my old Philips sig gen lost the cap on one of its knobs, it drives me nuts, completely nuts.
This week I saw an old Philips scope of the same era of products, for parts (missing rear cover for once), only 10 Euros, and only 6,50 shipping (half the normal rate). So I bought the scope just so I can get a replacement cap for that incomplete knob...

Shipping was incredibly fast, only 24 Hours ! 

I just could not believe it.

Just unpacked it, then realized... the cap I need is for a SMALL knob (fine tuning of the frequency).... but the scope has no small knobs : Only "normal" sized knobs ! 10 of them, 7 in the colour I need, 3 in a different colour. They are the perfect knob if my sig gen had a problem with its "Amplitude" setting knob... but it's not the one I need !

Well, at least now I have a whole bunch of spare parts to do whatever whenever...
At the back I noticed some luxury usually seen on '70's Teks : socketed transistors ! On a bottom of the barrel basic 10MHz scope ?! 

[factory]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

I don't know about crystals wearing out, but have certainly come across shattered ones in stuff at work.

David

That’s just extremely rapid wearing out  .I’ve seen some of them get dicky after a few years. I’ve mostly destroyed them past forensic analysis trying to find out why exactly. I had one Racal OCXO Crystal drift so far out of tolerance it was useless.

Found a picture of one I opened up afterwards, I don't know if it failed in service or maybe had a problem with the ultrasonic cleaner.


David

[mnementh]

Be careful. Your probe is a capacitive load and will potentially stall the oscillator or pull the frequency off. Really need a FET probe for that stuff. Bob Pease describes a cheap DIY one in Troubleshooting Analog Circuits.

Also worth replacing the Crystal. Sometimes they wear out apparently!

Edit: also doing terribly here on the test gear collection again 

Yeah, I know... but I was just looking for signs of life there. Considering capacitive loading, I've tried probing with and without a monitor on pin 15. As I know I'm able to get a consistent 30-ish seconds of oscillation with it right now, pretty sure that probing one or two output pins immediately after power cycling the thing, then moving on to the next, etc... the lack or presence of a signal is still valid data. If not, then replacing those 22puff caps should put the point to rest.

Also, I tried the 12MHz cap from the USB-ASP with similar behavior; sadly, still no 💓 output from any other pin.

I've shopped some 16MHz crystals, but all that's readily available is 20pF versions commonly used with Ardu; I might make that attempt after I track down some 22puff 0602 caps.

mnem
 

Is it not possible to provide a 16MHz signal via your signal generator to test it with?

The oscillator input is a differential pair at pin 15 and pin 13 which carries a DC bias. I'm leery of going that route until I've exhausted passive components; from my searches, it appears this CPU/PCB is unobtanium as it has device-specific firmware which requires special service jigs to flash. Also, this receiver has a real value of $100-150 and I still need a remote for it; I cannot really spend a lot of money on parts like that PCB or capacitor kit unless I can justify them for other use after the fact. I may just order a cheap-cheap 0603 cap kit from China (and some crystals) and put the damned thing in the Cupboard o' Doom til they arrive.

Right now I'm just going to step back from this project for a while; it's bugging me and I actually have other priorities right now. We just received notice that our property owner has decided to move to BC, and is selling out. We may or may not have ~60-90 days to find a new place & move.

mnem