Test Equipment Anonymous (TEA) group therapy thread

[mindcrime]

I spent 25+ years post Uni 'making do' at home with very minimal gear

As my .sig hints, I get satisfaction from getting more than expected out of minimal gear, partly because that requires understanding and imagination. I don't respect people who say only the latest and greatest is acceptable.

I can relate to that. And I also do appreciate the problem-solving enjoyment aspect of figuring out a way to do something with "less than ideal" gear. And heck, all this old/obsolete/antique HPAK kit is still "less than ideal" by somebody's standard. But there are times when I just want to get something done in short order, so I like having my shelf of nice, modern, modestly feature-rich gear available as well.

I've basically structured my approach like this:

1. the base of my lab is mostly Rigol kit, bought new, and going with something higher than the lowest-end of the Rigol range, but less than the highest end of the Rigol range. Of course, keeping in mind that even the most "high end" Rigol kit isn't "high end" by comparison to some of the stuff put out by Keysight, Tek, R&H, etc. 

2. More specialized / niche stuff I go with HPAK kit, bought used. Most of this kit is relatively inexpensive, with the biggest exception being my Keysight logic analyzer, which was a bit pricey by my standards, even bought used at a substantial discount. I splurged on that mainly because I have this grand idea that I'm going to start getting more into hardware reverse engineering stuff, and thought it would be especially handy to have a nice logic analyzer there.
 

[tggzzz]

I spent 25+ years post Uni 'making do' at home with very minimal gear

As my .sig hints, I get satisfaction from getting more than expected out of minimal gear, partly because that requires understanding and imagination. I don't respect people who say only the latest and greatest is acceptable.

Not completely true. For really "interesting" problems you need top gear AND all understanding, imagination and luck you have, plus some black magic thrown in as well.

I wouldn't argue with that, but those cases are relatively rare and if you have that kind of problem then you probably have sufficient expertise to justify it.

[tggzzz]

I spent 25+ years post Uni 'making do' at home with very minimal gear

As my .sig hints, I get satisfaction from getting more than expected out of minimal gear, partly because that requires understanding and imagination. I don't respect people who say only the latest and greatest is acceptable.

I can relate to that. And I also do appreciate the problem-solving enjoyment aspect of figuring out a way to do something with "less than ideal" gear. And heck, all this old/obsolete/antique HPAK kit is still "less than ideal" by somebody's standard. But there are times when I just want to get something done in short order, so I like having my shelf of nice, modern, modestly feature-rich gear available as well.

I've basically structured my approach like this:

1. the base of my lab is mostly Rigol kit, bought new, and going with something higher than the lowest-end of the Rigol range, but less than the highest end of the Rigol range. Of course, keeping in mind that even the most "high end" Rigol kit isn't "high end" by comparison to some of the stuff put out by Keysight, Tek, R&H, etc. 

2. More specialized / niche stuff I go with HPAK kit, bought used. Most of this kit is relatively inexpensive, with the biggest exception being my Keysight logic analyzer, which was a bit pricey by my standards, even bought used at a substantial discount. I splurged on that mainly because I have this grand idea that I'm going to start getting more into hardware reverse engineering stuff, and thought it would be especially handy to have a nice logic analyzer there.

No disagreement from me! If you have access to good tools, then  use them.

[beanflying]

Ahhh the self satisfied smile of a successful enablement  I will leave the victim winner of the deal to add more...... 

[mansaxel]

[submarines]

We have three museum subs in Sweden, our first, HMS Hajen and a quite late one, HMS Neptun at the main naval museum, and a WW2 one, HMS U3, at the city museum in Malmö, where subs have been built and still are. I've been to them all.

[med6753]

The parts from Mouser are out for delivery via FedEx. The 6BY8 tube finally stopped circling the sewers of NJ and is at my local PO for delivery.

Tackling this Type 547 today and come hell or high water I'm going to get something done with it. Either get the PSU up or toss it out the window. 

MindCrime.....can relate. No wife, no debt and added bonus of retired so I can do what I damn well please. My woman does not live here and maintains her own residence and we both prefer it that way. If I showed you a picture of what my bench looked like say 5 years ago compared to now you'd be amazed. This is definitely my time and I'm taking full advantage of it. 

[McBryce]

Anyone near Berlin looking for a Boat anchor? https://www.ebay.de/itm/254978636457 (with modules!)

McBryce.

[Saskia]

thanks, no. Hubby is currently complaining that he cannot bid on the axe collection he is eyeing as we are out of space.

[tautech]

thanks, no. Hubby is currently complaining that he cannot bid on the axe collection he is eyeing as we are out of space.

Any special types...throwing, double bit, racing ?

[nfmax]

Not completely true. For really "interesting" problems you need top gear AND all understanding, imagination and luck you have, plus some black magic thrown in as well.

I wouldn't argue with that, but those cases are relatively rare and if you have that kind of problem then you probably have sufficient expertise to justify it.

For the really, really, interesting problems, no one has sufficient expertise - yet

[tggzzz]

Not completely true. For really "interesting" problems you need top gear AND all understanding, imagination and luck you have, plus some black magic thrown in as well.

I wouldn't argue with that, but those cases are relatively rare and if you have that kind of problem then you probably have sufficient expertise to justify it.

For the really, really, interesting problems, no one has sufficient expertise - yet

Just so. I've been fortunate to be in such a position

For those that denigrate adequate but old equipment that can be used with skill and imagination, I have a simple question: "what scope would you use to debug the world's fastest scope?"

[Kosmic]

I am not an addict, I can stop any time... I am not an addict, I can stop any time... I am not an addict.. oh hell, who am I kidding?

So I just broke down and bought an HP 53310A Modulation Domain Analyzer on Evilbay.



Why? I don't know. Why ask why? Why are we here? Where is all this going? Emacs or Vi? KITT or KARR? Blue Thunder or Airwolf? Too many questions! Too many problems, the world can't solve
Too many people, no-one wants to be involved
(Lack of communication, back off)



#RIPTawnyKitaen

Make sure you check the PSU. If it's original, you need to change all (I really mean all) the electrolytic capacitors. Personally, I don't change capacitors when they are working fine, but in that case it is necessary.

The PSU of the 53310A (and same vintage HP scope) is notorious for leakage and failures.

Mine was dripping 

[Kosmic]

I have an electric mower. It's got a cord. I aggressively avoid battery-powered devices, especially when they don't have to be (that is, the usage pattern would allow them to be powered by mains directly). When I saw a battery Dremel the other day, I thought "Oh, no, not another thing they've ruined". Then I went back to using my Proxxon FBS240E, which is mains powered. 

I concur. The last thing I need is another rechargeable battery to maintain. I love my corded electric mower. No hassle. (Practically) no maintenance. No fuel storage. Little noise. I've had it so long I can't even get replacement parts for it anymore.

Same here. It came with the house many years ago and still working fine 

[Brumby]

Ahhh the self satisfied smile of a successful enablement  I will leave the victim winner of the deal to add more...... 

 

[0culus]

I am not an addict, I can stop any time... I am not an addict, I can stop any time... I am not an addict.. oh hell, who am I kidding?

So I just broke down and bought an HP 53310A Modulation Domain Analyzer on Evilbay.



Why? I don't know. Why ask why? Why are we here? Where is all this going? Emacs or Vi? KITT or KARR? Blue Thunder or Airwolf? Too many questions! Too many problems, the world can't solve
Too many people, no-one wants to be involved
(Lack of communication, back off)



#RIPTawnyKitaen

Make sure you check the PSU. If it's original, you need to change all (I really mean all) the electrolytic capacitors. Personally, I don't change capacitors when they are working fine, but in that case it is necessary.

The PSU of the 53310A (and same vintage HP scope) is notorious for leakage and failures.

Mine was dripping 

Somewhere around here someone already compiled the BOM you need for the replacement job.

[kj7e]

See here for HP 53310A Power Supply repair BOM;

https://www.eevblog.com/forum/repair/hp-53310a-power-supply-troubles/msg2365593/#msg2365593


BOM direct link;
https://www.eevblog.com/forum/repair/hp-53310a-power-supply-troubles/?action=dlattach;attach=716793

[BU508A]

The parts from Mouser are out for delivery via FedEx. The 6BY8 tube finally stopped circling the sewers of NJ and is at my local PO for delivery.

Tackling this Type 547 today and come hell or high water I'm going to get something done with it. Either get the PSU up or toss it out the window. 

MindCrime.....can relate. No wife, no debt and added bonus of retired so I can do what I damn well please. My woman does not live here and maintains her own residence and we both prefer it that way. If I showed you a picture of what my bench looked like say 5 years ago compared to now you'd be amazed. This is definitely my time and I'm taking full advantage of it.

The Days of Papa Tek Smurf .... ah haaa haaaa ....

 

[mnementh]

I have an electric mower. It's got a cord. I aggressively avoid battery-powered devices, especially when they don't have to be (that is, the usage pattern would allow them to be powered by mains directly). When I saw a battery Dremel the other day, I thought "Oh, no, not another thing they've ruined". Then I went back to using my Proxxon FBS240E, which is mains powered. 

I concur. The last thing I need is another rechargeable battery to maintain. I love my corded electric mower. No hassle. (Practically) no maintenance. No fuel storage. Little noise. I've had it so long I can't even get replacement parts for it anymore.

Same here. It came with the house many years ago and still working fine 

I think the dividing line here is how much of an actual "yard" you have to deal with. Our last place had a front yard approx 4m x 8m... and the back was patio. The house came with a .4m cut electric mower, and even tho wrangling the cord was a PITA, it was only a few minutes a few times a month, so I put up with it.

This place is tiny inside, but large front & back yards (for the 'burbs); more like 10m x 15m plus 25m x 50m in the back. That takes over an hour just to mow even with a .55m cut self-propelled gas mower. Even if it weren't half the usable cut of my gas mower, no way in hell I'd put up with wrangling a cord over that area.

The trick to gas-powered lawn tools is maintenance; and it doesn't take much to ensure your gas-powered freedom works every time and with little difficulty starting. Anything made in the last 30 years has electronic ignition which is crazy reliable, so even the black magic of points & condenser is no longer a factor. Just keep the carb clean and not gummed up by using high-octane fuel and fuel stabilizer and you're 90% of the way there; the rest for the most part is simple cleaning and filters.

It used to be that learning these very basic mechanicking skills was considered a rite of passage to manhood; nowadays, anything with "learning" in it seems to be a dirty word. 

mnem

[AVGresponding]

Just been doing a calibration/adjustment of my Black Star 4503, it's only taken me two years to get around to it...

Had a bit of a "oh frell" moment during the 400VDC range...
The procedure is to apply a value near the top of the range, enter it, then short the leads and enter five zeroes. I was using my VWR 300 EP supply, as the LKG 2500 is too much of a nuisance to set up. Entered the high value, then unplugged one of the leads prior to shorting, and the meter display went to all segments, then blanked from left to right, apparently dead.   

Disconnected everything and cycled the power on the meter; luck is my friend today, it repowered, with none of the cal data I'd been putting in (all the ohms ranges, and the VDC as far as 400) having been lost.   
Must have been some coupling through one of the Y caps causing an overload?

This meter has a 40MΩ range, which is above the capability of my Fluke 8840A, my only recently calibrated meter, so I had to rely on my Keithley 2000 and the mystery acquisition to check the value of the 30MΩ resistor I used. Thank heavens for old CRT tvs...


One thing I noticed immediately when I cycled the power was that I no longer get the calerr and toterr messages while it boots, so it's already a happier camper than before. Now to carry on with the VAC and then current ranges. I'll leave the 1000VDC and 750 VAC ranges alone for now; I'll not be using it on anything like that anyway, that's the bailiwick of handhelds imo.

[med6753]

See schematic. This is the how the filament string is laid out for the Type 547. I pulled V91 (lower right) which is the +100V series string to the plug-in. That effectively opens that load path. I also pulled V584 and V574 (Upper left) which have their filaments elevated to +100V. That opens that load. The +100V still refuses to come up but at least there's no smoke. 

I did verify that the bulk DC voltage from the rectifiers/transformer is good for both the +100V and -150V supplies.

For the time being I'm tired of beating my head against the wall.   I've got that hospital stay coming up Monday and I'm just too distracted to go any further at this point. Maybe late next week I'll get back into it. Objective is completely isolate all loads from the +100V plus re-cap all the tubular/ceramic capacitors in the entire PSU plus also replace the balance of the electrolytics in the +100V and -150V. I have all those parts on hand. Plus the 6BY8 tube will arrive today.   

[kj7e]

Since I'm here, I have been waiting for the right HP 419a DC Null Meter to show up for about 5 years.  Finally found one that met my search criteria.  It arrived well packaged and even seemed to work properly (minus the 35 year old NiCad's and the mercury null supply cell).

Now the bad, while cleaning up some corostion from the leaky NiCads and making some adjustments, the hot side of the AC power on the non fused side of the fuse eyelet made contact with one of the NiCads and put 120v AC into the +13v line   

I found nearly every silicon part on the A2 power supply/chopper blocking amp board fried, all but one 2n3053.  So off to search for 2n3053's, some secret PNP HP used that the best I can cross ref came to an NTE106, and 2n3391's.  I was lucky and found NOS for the 3053's and other parts.  I was please to see no damage to the chopper block or the A4 amplifier board.

It was working again, time to make a NiCad 24v battery and find a replacement for the mercury cell.  This unit is really a battery powered device and the power supply is really just a constant current trickle charger for the battery.  In normal operation, the power supply is limited to 10mA, in the "Fast Charge" mode 18mA.  The meter itself draws about 5mA, leaving 5mA to trickle to the battery, in the Fast Charge mode no power is sent to the meter.   I thought about using Li-FePO4 cells but didn't want to add a CV to the unit, so I decided to stick to NiCad's.  After all, they have worked for 45 years in this box already.  Found 300mAh 2/3 AAA NiCads on eBay with tabs for cheap (like 26 cells for $15 total), the OEM cells were rated at 225mAh, so these should do just fine.  Built up the pack, wired it in and it works great.  After some testing I decided to use a CR123a lithium cell with a 2.7k series resistor to bring the battery back to within range and show proper full scale.  The current draw is about 650uA, so a 1.5Ah CR123a should run for well over 2000 hours.  Easy to find, cheep and good long life stability.

Video of the meter in use and just how sensitive it is,  you have to pay close attention to Thermal EMF not to trick you with this one.

[kj7e]

And then with the Null Battery installed.  Null function demo;

[BU508A]

Today arrival: the Vishay VHA516-6T 1MOhm resistors.
Looking good ...     



The strange colours are reflections while I took the photos.
Later, I'll hook up my DMM7510 and check for their values.
Will keep you posted.

[Specmaster]

Just been doing a calibration/adjustment of my Black Star 4503, it's only taken me two years to get around to it...

Had a bit of a "oh frell" moment during the 400VDC range...
The procedure is to apply a value near the top of the range, enter it, then short the leads and enter five zeroes. I was using my VWR 300 EP supply, as the LKG 2500 is too much of a nuisance to set up. Entered the high value, then unplugged one of the leads prior to shorting, and the meter display went to all segments, then blanked from left to right, apparently dead.   

Disconnected everything and cycled the power on the meter; luck is my friend today, it repowered, with none of the cal data I'd been putting in (all the ohms ranges, and the VDC as far as 400) having been lost.   
Must have been some coupling through one of the Y caps causing an overload?

This meter has a 40MΩ range, which is above the capability of my Fluke 8840A, my only recently calibrated meter, so I had to rely on my Keithley 2000 and the mystery acquisition to check the value of the 30MΩ resistor I used. Thank heavens for old CRT tvs...


One thing I noticed immediately when I cycled the power was that I no longer get the calerr and toterr messages while it boots, so it's already a happier camper than before. Now to carry on with the VAC and then current ranges. I'll leave the 1000VDC and 750 VAC ranges alone for now; I'll not be using it on anything like that anyway, that's the bailiwick of handhelds imo.

You will like using the 4503, it is a very capable meter I find and is one of my more favoured meters along with the 1906

[Saskia]

thanks, no. Hubby is currently complaining that he cannot bid on the axe collection he is eyeing as we are out of space.

Any special types...throwing, double bit, racing ?

all kinds of, preference would most likely be battle axes, sacrificial axes, just about anything that can be used to ruin someone's day.

He's such a romantic, at one time he went to pick up his viking style fighting axe and gifted me with a sacrificial axe (for when I have the need to sacrifice a goat to Odin).