Test Equipment Anonymous (TEA) group therapy thread

[AVGresponding]

My AC voltage source is good for up to 5A/1100V, but with a maximum voltage burden of 10VA, so not really usable as a power supply.[/color][/size][/b]

What type (make/model) is this?
10VA would be a spec for kind of a calibrator or something ...

It's a 0.05% spec AC/DC V/I source, with selectable 50/60/400Hz. It's an RFL Boonton/Clarke Hess 828.

Nice one, clearly doubles as a calibrator as long as the spec is good enough for your DUTs.

Its great strength (for me) is the good stability; it allows me to use it to cross check against one of my good, calibrated meters.

[Mr. Scram]

mnem
How many digits did you lose in the process...?

They don't call him "Mr. 5,5 digits" for nothing.

[mnementh]

          BWAHAHAHAHAHA!

mnem
He'd flip us the bird... but he's ill-equipped.

[med6753]

HP 412A

(quick edit there to remove the wrong meter  )

Well that didn't take long. You win a picture of the glassware...

McBryce.

Thank you 

Ooh Sprague Black Beauties.

Supposedly the red stripe black beauties are a higher quality construction than the yellow stripe. But I still don't trust them and they get binned.

[AVGresponding]

Update on my HP34401A with dodgy display.
Selller came right back and said OK to a refund. 

And it's relisted for £425...

It will sell.

I reckon if I threw some new probes in and got a handle I could get £500 for mine

Utter madness. It can't be even a year since I bought my minty Agilent round button 34401A, and it was around £300 iirc.

I could have got one of them the other day for about the same price if I wasn't napping like I was 80 when the auction ended 

Oooops...

Here's some more ebay picks to ease the annoyance.

Price on this may be a bit salty, given the description, but they are open to offers:  https://www.ebay.co.uk/itm/334477506172





I don't know why I post these, they always either get silly bids, or have silly reserve prices:  https://www.ebay.co.uk/itm/155045337506





For when you need to measure your tzzzzzt:  https://www.ebay.co.uk/itm/255592412251





Some enheaviment:  https://www.ebay.co.uk/itm/165542188711



One wonders if that display is the same as the 3468/78, certainly looks possible...



Another one likely to sell for more than it's worth:  https://www.ebay.co.uk/itm/234598079111





I don't even like the form factor of these:  https://www.ebay.co.uk/itm/234598240604





More enheaviment, this seller likes to pack things like this in a single layer of newspaper, or maybe a plastic bag:  https://www.ebay.co.uk/itm/255594888686





Even more enheaviment, in Birmingham this time:  https://www.ebay.co.uk/itm/265749447389





Tek test and tweak tool:  https://www.ebay.co.uk/itm/165542397349





Tek trauma triggerer:  https://www.ebay.co.uk/itm/134149403603





R&S power meter with some fixtures:  https://www.ebay.co.uk/itm/225038288303





Somewhat older Racal power meter from the same seller:  https://www.ebay.co.uk/itm/225042103595

[Cubdriver]

HP 412A

(quick edit there to remove the wrong meter  )

Well that didn't take long. You win a picture of the glassware...

McBryce.

Edit: Picture of the "messy side" with it's bulb-powered Synchron.

I started messing with the one I have here a few months back; the synchrotron motor wasn't spinning and three out of four lamps were burned out.  A teardown and a bit of lube got the motor running again, and I was able to order replacement lamps, but of course fitting them was a royal PITA as the new ones had much thinner pins and it was necessary to gently crimp the little split holders a bit smaller without damaging them - getting them tight enough to grip the spindly lamp leads but not so much as to be crushed was a delicate balancing act.  Damned low quality replacements.   It then went back in the queue for lack of a manual at the time, and I never put the pictures up.  Cool old piece of gear.

-Pat

[Specmaster]

Update on my HP34401A with dodgy display.
Selller came right back and said OK to a refund. 

And it's relisted for £425...

It will sell.

I reckon if I threw some new probes in and got a handle I could get £500 for mine

Why, has yours got a dodgy display as well then?

[bd139]

Update on my HP34401A with dodgy display.
Selller came right back and said OK to a refund. 

And it's relisted for £425...

It will sell.

I reckon if I threw some new probes in and got a handle I could get £500 for mine

Why, has yours got a dodgy display as well then?

No. This is a comment about the pricing disparity more than anything. I’m keeping mine 

[Specmaster]

What the... hell model of car have you got, then? I thought Volvo was supposed to be a premium brand, and they can't even fit tweeters to all doors and channels  Mine even has mid range and tweeters, woofer at the bottom, mid range in the middle and tweeters right at the top by the door latch. Only 4 pop rivets hold your woofer, did you get any distortion / vibration of the speaker chassis on deep bass as a result of tahat or are your speakers slightly smaller than most, mine had 6 rivets to secure it to the door skin. I should think you certainly notice the extra top end now?

This was, as noted, the bottom rung of the quality ladder. There were several equipment levels available above this; my older cars on the same platform dodid indeed have tweeters, also as noted. Buying a used car you can't be too picky with things like this; I was happy to get the 4WD, large Diesel, semi-leather upholstery version, with hitch and OEM roof rack bars, for a very good price, with a known service record.

The top end is indeed noticeable now!

I put Alpine 3-way splits in my car, made a huge difference to the audio quality.
I spend like 2.5 hours a day in the car commuting in and out of Tokyo, so I wanted some good audio to help me endure the idiots on the road. 

That is the same logic as I applied when I ordered my car, which was at the time a company car. I would often spend upwards of  6 hours at a time in it, so I wanted some good audio and for the times I'd be hanging about in it stuck in jams on the motorways or on site, I also specced the car with a DVD player and TV tuner with surround sound system. Now of course I still get to enjoy all those creature comforts as I brought the car when I retired  That was my plan all along 

[Specmaster]

What the... hell model of car have you got, then? I thought Volvo was supposed to be a premium brand, and they can't even fit tweeters to all doors and channels  Mine even has mid range and tweeters, woofer at the bottom, mid range in the middle and tweeters right at the top by the door latch. Only 4 pop rivets hold your woofer, did you get any distortion / vibration of the speaker chassis on deep bass as a result of tahat or are your speakers slightly smaller than most, mine had 6 rivets to secure it to the door skin. I should think you certainly notice the extra top end now?

This was, as noted, the bottom rung of the quality ladder. There were several equipment levels available above this; my older cars on the same platform dodid indeed have tweeters, also as noted. Buying a used car you can't be too picky with things like this; I was happy to get the 4WD, large Diesel, semi-leather upholstery version, with hitch and OEM roof rack bars, for a very good price, with a known service record.

The top end is indeed noticeable now!

I put Alpine 3-way splits in my car, made a huge difference to the audio quality.
I spend like 2.5 hours a day in the car commuting in and out of Tokyo, so I wanted some good audio to help me endure the idiots on the road. 

AirPods pro with transparency mode on. Also works for the idiots when you get out of the car as you can turn on noise cancellation mode 

Not so sure that they are allowed to be used while driving, certainly not worth the hassle of trying to explain to traffic cops that you can still hear emergency two tone horns and other shit.

[tggzzz]

For when you need to measure your tzzzzzt:  https://www.ebay.co.uk/itm/255592412251

I have a P6013 that I ought to sell (since I've also got a P6015).

[bd139]

What the... hell model of car have you got, then? I thought Volvo was supposed to be a premium brand, and they can't even fit tweeters to all doors and channels  Mine even has mid range and tweeters, woofer at the bottom, mid range in the middle and tweeters right at the top by the door latch. Only 4 pop rivets hold your woofer, did you get any distortion / vibration of the speaker chassis on deep bass as a result of tahat or are your speakers slightly smaller than most, mine had 6 rivets to secure it to the door skin. I should think you certainly notice the extra top end now?

This was, as noted, the bottom rung of the quality ladder. There were several equipment levels available above this; my older cars on the same platform dodid indeed have tweeters, also as noted. Buying a used car you can't be too picky with things like this; I was happy to get the 4WD, large Diesel, semi-leather upholstery version, with hitch and OEM roof rack bars, for a very good price, with a known service record.

The top end is indeed noticeable now!

I put Alpine 3-way splits in my car, made a huge difference to the audio quality.
I spend like 2.5 hours a day in the car commuting in and out of Tokyo, so I wanted some good audio to help me endure the idiots on the road. 

AirPods pro with transparency mode on. Also works for the idiots when you get out of the car as you can turn on noise cancellation mode 

Not so sure that they are allowed to be used while driving, certainly not worth the hassle of trying to explain to traffic cops that you can still hear emergency two tone horns and other shit.

Fair points. I don't drive with them in as I quite like offensively loud music so I can't hear the two tone horns either 

[HighVoltage]

For when you need to measure your tzzzzzt:  https://www.ebay.co.uk/itm/255592412251

I have a P6013 that I ought to sell (since I've also got a P6015).

The bad thing with the P6015 is that it has to be filled with FREON and that is almost unobtanium
The P6015A is gel filled and last forever, if treated well.

[mnementh]

Price on this may be a bit salty, given the description, but they are open to offers:  https://www.ebay.co.uk/itm/334477506172

I don't know that the price is bad at all. Let's break it down:

$40 - 54658A RS-232/Math & Acquisition Module

$20 - Documentation & Probe

$25 - Handle good for any 546xxx family scope

$30 - PSU - 5460xx & 5464x family scopes (IIRC that's all these fit)

$30 - monitor - 5460xx & 5464xx family scopes (maybe 5462xx &5464xx as well?)

$30 - Front Encoder PCB & Keypads - 5460xA & 5464xA family scopes
                   (I believe can be fitted to D series by adding missing diodes/encoders)

$30 - Front Bezel - 5460xA & 5464xA family scopes
                   (will fit any Non-D model if you can tolerate a little labelmaker rebadging)

$20 - Random screws, knobs, power button assembly, brightness knob to fix any of the above.



Yeeeah.... I was talking to bd139 aboot this earlier; I just finished fixing up that 54600A I bought to get the 54657A GPIB/Math & Acquisition module. I was thinking about flipping it since I bought that Le-Siglent; but seriously, I can't get as much selling it as it's worth as spares for my 54645A or as parts to fix up one of the newer family 546xxx scopes with 4MB MegaZoom. Maybe half that.

Meanwhile, skanky bust-ass TDS-2x0s with tiny horrible screens and half the already-pathetic memory depth as these non-MegaZoom scopes still get $2-300. Yeah they have 1GS/s rate; but it is almost worthless at that depth.

mnem
 

[factory]

HP 412A

(quick edit there to remove the wrong meter  )

Well that didn't take long. You win a picture of the glassware...

McBryce.

Edit: Picture of the "messy side" with it's bulb-powered Synchron.

I started messing with the one I have here a few months back; the synchrotron motor wasn't spinning and three out of four lamps were burned out.  A teardown and a bit of lube got the motor running again, and I was able to order replacement lamps, but of course fitting them was a royal PITA as the new ones had much thinner pins and it was necessary to gently crimp the little split holders a bit smaller without damaging them - getting them tight enough to grip the spindly lamp leads but not so much as to be crushed was a delicate balancing act.  Damned low quality replacements.   It then went back in the queue for lack of a manual at the time, and I never put the pictures up.  Cool old piece of gear.

-Pat

Looked at the picture & thought 412A too, couldn't have been anything else due to the ohms adj. pot on the back.

I've repaired both an 412A & 412AR (rack version), both are a bit older with fixed power cords, I preferred working on the 412AR, due to the amount of disassembly required to get to the open circuit 1500uF cap in the 412A.  This cap was open on both, they also had leaky bumble bomb caps, some already replaced in the distant past, all now replaced, I also had issues with poor contact in the lamp sockets.
The only concern I still have with them, is the plastic the switch wafers are made from, the service notes warn against using certain cleaners that will damage them, both mine have some cracks, presumably from incorrect cleaner being used (not by me), the 412A is the worst.


David

[mnementh]

This is the condition of the one I just bought.

Handle and paintwork is original, dial is snow white.   - McBryce.

That is pretty close to mint. Providing it works, you're lucky. Schurter makes Mickey Mouse jacks (IEC 60320 C6) that almost fit in place of the PH-163 atrocities.

Yeah... IMO, in many cases that's much more important on this kind of gear. You can spend lots of time fixing up the guts, and when you're done you'll have a unit that looks and works as good or better than new.

But no amount of work can undo all the ravages of time and neglect (or a unleashed smurf with a hacksaw blade  ), especially if they've been allowed to ravage  unchecked for too long...

mnem
 

[bd139]

Seeing all the old stuff makes me want some new stuff 

Got my eye on a SPD3303X-E now...

Edit: ... but I can't get over the third output situation and the banana plug spacing which makes it look like this:

[Vince]

Some action today...

Dragon sent me knobs to dress the naked front panel of my HP 54645D MSO scoppy, looks much better now for sure, thanks !
Looks like a million dollar scope now 

Also donated 4 little DC/DC step down converter boards with the MP1584 chip.

Then I received also today an envelope from Sweden, got RIFA caps to replace the one in the HP scope PSU, and also a set of lovely Hirshcmannnlong grabbers. Sadly the rfd one got broken during transport, sad.... the hard plastic hand piece is badly cracked at the base of the grabber, but still holding together somehow and still works, smoothly at that. It's still perfectly functional. Tried to bend it back into shape / straighten it, no joy, it wants to stay bent, ah well... maybe at least I could fill the gap/crack with super glue ? And maybe add a layer of two of red heat shrink tubing to restore thye electrical insulation ? because having my fingers right on that crack with HV inside the crack does not appeal to me very much, I must confess..

So I replaced that RIFA. PSU board was easy and quickly to remove from the scope. Paid extra attention to plastic rod operating the mains switch, since you said it could break easily... got lucky, it came out and back on, with no drama 

You also warned me about the difficulty to remove the cap due to one lead being connected to a fat trace or ground plane. That was a big worry for me as my old Weller Magnastat iron is only 50 Watts 
Luckily, it managed to remove the cap within a reasonable amount of time. 10 or 20 seconds top, nothing to crazy. Still, a much more powerful iron is on my wish list.

Replacement cap is twice the value 100nF instead of 47,F, so that package is larger, but still juuust about fits in the confined space that this cap is allowed to occupy, closely surrounded that it is by this tall heat sink and massive filter cap, mostly. 
Pin pitch is larger as well, 20mm instead of 15mm. No big deal I bent one of the pins. However that meant that clearance / isolation with other surrounding discrete components, was reduced. So I had to chose which side of the capacitor was the safest for this reduction in clearance. Luckily one side was much safer than the other so I was relieved, no accident / sparking waiting to happen here. 

Putting the new cap was a chore... had to clean the pad holes first, and it's not easy (don't have a desoldering gun) as the diameter is small  and the pad hair thing as well, and my solder sucker doesn't work at all in that kind of scenario. So I had only solder wick at my disposal (maybe I should get a set of needles to unplug holes... will ad that to my shopping list). The easiest of the two  was not too difficult, after a few attempts, but the hard one with the fat trace, my god.... took 15 attempts ! I couldn't even give up on it because I had no other means, I HAD to make it work ! 

So I could then put the new cap in place. Soldering was not cool because the pins are soldered on both sides and you just can't know for sure if the solder managed to reach the other side and make a good connection, since the component is sitting flush on the board (and access is so poor on this board with all the surrounding components !! ). So that's where I was paradoxically HAPPY that the new cap was bigger and I had to bend one lead... this meant the cap was NOT sitting flush onto the board any more, so with a good flash light I could just barely manage to see the solder joint under the cap ! 


So I put the scope back togetehr and what do you know, it still works, I have not killed it !!   


Then for the grand finale I though I would gather all the bits together and make something out of it :

Used the scope to test Dragon's DC/DC board, connecting to my lab supply with Mansaxel's grabbers, and take some measurements for TEA content.
It just doesn't get any better than this eh ? 

So I thought I could look at the ripple, and for example measure the switching frequency, see if it matched the theory. Why not.
So I pulled the datasheet for the chip, looked up the formula. Frequency is set by a single resistor. Found it on the board, but it's marked " 01D" which is a bit strange for a resistor eh ? What does that mean for a resistor.... so instead I measured it with a DMM. about 100kohms.

so I ran the numbers and if I get my math right I should get about 900kHZ, which sounds plausible given the tiny size of the board yet high current output... and ads up with the datasheet saying the chip can operate between 100kHz and 1.5MHz.

OK so I wire the board up, and scope the ripple. See for yourself....  TWO VOLTS peak to peak, and 40Hz.. yes 4x10 ! 

Eh ?! 

Then I try to vary the output voltage with the tiny trimmer.. with careful use of a tiny screw driver... seemed to react OK for 10 seconds then suddenly it would not react anymore, I would get full output voltage permanently. I guess a bad joint on the trimmer, it's out of circuit now ?! 

So not very good isn't it ! 

I got unlucky, I will try another board and report....


Thanks Dragon and Mansaxel !! 

[Vince]

...

[bd139]

Those DC converters need a load to stop them oscillating frantically. I did some tests on some ages ago. Surprisingly I couldn't murder them!

[AVGresponding]

Price on this may be a bit salty, given the description, but they are open to offers:  https://www.ebay.co.uk/itm/334477506172

I don't know that the price is bad at all. Let's break it down:

$40 - 54658A RS-232/Math & Acquisition Module

$20 - Documentation & Probe

$25 - Handle good for any 546xxx family scope

$30 - PSU - 5460xx & 5464x family scopes (IIRC that's all these fit)

$30 - monitor - 5460xx & 5464xx family scopes (maybe 5462xx &5464xx as well?)

$30 - Front Encoder PCB & Keypads - 5460xA & 5464xA family scopes
                   (I believe can be fitted to D series by adding missing diodes/encoders)

$30 - Front Bezel - 5460xA & 5464xA family scopes
                   (will fit any Non-D model if you can tolerate a little labelmaker rebadging)

$20 - Random screws, knobs, power button assembly, brightness knob to fix any of the above.



Yeeeah.... I was talking to bd139 aboot this earlier; I just finished fixing up that 54600A I bought to get the 54657A GPIB/Math & Acquisition module. I was thinking about flipping it since I bought that Le-Siglent; but seriously, I can't get as much selling it as it's worth as spares for my 54645A or as parts to fix up one of the newer family 546xxx scopes with 4MB MegaZoom. Maybe half that.

Meanwhile, skanky bust-ass TDS-2x0s with tiny horrible screens and half the already-pathetic memory depth as these non-MegaZoom scopes still get $2-300. Yeah they have 1GS/s rate; but it is almost worthless at that depth.

mnem
 

The maths module may well be faulty, given the seller says they can't get the FFT to work. Add to that the list of repairs the seller made (not trying to disrespect them, but you have no way of knowing the quality of them).

The probe is a no-name cheapo jobby from the looks of it.

TDS 210s make so much there? Wow... they are horribly overpriced here but only half that...

[mansaxel]

Those DC converters need a load to stop them oscillating frantically. I did some tests on some ages ago. Surprisingly I couldn't murder them!

Also, to make them EMI/RFI compliant, a parallel cap on either side, and a series inductance on the input positive will do wonders.  I've got a bunch of some similar ones here, and I'm going to make 5V from car 12V with one, to feed the stereo from a bluetooth input module, but not without those extra components.

[mansaxel]

...

That's a pity. I bought a rather large stash of those a couple years back, and the Super Kleps is such a nice grabber in many ways. Happy to help!

[cyclin_al]

3/ The two large wires connected together are the CPC (earth) and Netural. A connection which according to some does not exist.

I am not sure of the Canadian and USA differences, but my understanding for the GWN is that those are to be connected together in only one specific location, done by the electricity utility company.
Anything done within the house at or after the main panel shall not have the Earth and Neutral connected together.

Two reasons I can think of:
- no ground loop current
- correct functioning of GFCI protection

As for unused conductors; we are too cheap in the GWN to allow that situation to ever occur...  my vague recollection of the rule is that it is such a major PITA to be avoided at all cost.

[factory]

Interesting & slightly badly listed vintage DVM for those in the USA, cheap start price but could be expensive as it has a reserve. 
https://www.ebay.com/itm/295045755315



Also in the US, a BK Precision mirror I mean DMM. 
https://www.ebay.com/itm/115425145466



David