Test Equipment Anonymous (TEA) group therapy thread

[bd139]

I will make amends. My purchase rate of TE is higher than ever 

I got rid of the 7L12 because quite frankly it scared me. It could literally turn into a brick at any moment with no hope of repair. There are literally no parts mules for it or anything.

Looking at the pile of SA crap I got at the last PP auction, the HP 8557/8/9 SA plug-ins aren't any better, the same mechanical parts, switch wafers & knobs are broken/missing on most of them.
Clearly the mixer, Yig oscillator and attenuator are trouble too, judging by them either being missing or labelled as futzed, though I suspect some of that might have been the operators fault. 

David

Yes same with the SA's that were floating around today. I enquired about a couple. I was being pushed a 20GHz one for £60 and told what a good deal it was. But it came with a printed manual in a tesco carrier bag and a little zip lock bag taped on the front with some HP leaf contacts in it. He said he'd tried to repair it but not got around to finishing it. My daughter who was with me today actually laughed slightly too loudly at that. I passed on it.

[bd139]

...And now for something completely different. A small 50 ohm load. 10KW. And yes, that's the coax connector on the front 

There is something very, very wrong with me... I just got a raging nerd-boner. No idea what in the world I'd do with it... I just know I want... 

mnem
"Waaaatt...?"

Well two options:

1. Heat your house with it.
2. Stick your dick in it.

[mnementh]

...Next we have the HP 3311A function generator. Again it works absolutely fine. Paid £20 for it too. One of the feet fell to bits in the car but this is sort of expected.   

https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2255118/?topicseen#msg2255118

I could swear I saw something like this on the 3DP Knobs & feet thread; if not, Thingiverse.

Otherwise big stick-on feetses.

mnem
 

[factory]

Next we have the HP 3311A function generator. Again it works absolutely fine. Paid £20 for it too. One of the feet fell to bits in the car but this is sort of expected.

Will work out a new foot solution to this...

Didn't you 3DP one of those feet sometime ago?
Don't know why, but that rear foot always seems to crumble, on that type of case, the front one for the tilting bail, must be made from a different plastic.

David

I probably did. Can't remember that far back. I blocked my escapades in 3d printing out of my mind so I don't go down that rabbit hole again. Then again, never know what might happen 

Beanflying & VK5RC have done 3DP replacements, they are listed in the 3DP parts thread under 5300A, 5300B & 34702A.
https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2255136/#msg2255136
https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2472369/#msg2472369

Just need someone to go into mass production. 

David

[mnementh]

...And now for something completely different. A small 50 ohm load. 10KW. And yes, that's the coax connector on the front     

There is something very, very wrong with me... I just got a raging nerd-boner. No idea what in the world I'd do with it... I just know I want... 

mnem
"Waaaatt...?"

Well two options:

1. Heat your house with it.
2. Stick your dick in it.

So you're saying "Win-Win!!!" then...? 

mnem
I'll just start digging that hole for when SWMBO finds out...

[bd139]

Ok Newbury megapost. It has been 3 years since the last one. Bloody COVID.

So what did I bag?


Next we have the HP 3311A function generator. Again it works absolutely fine. Paid £20 for it too. One of the feet fell to bits in the car but this is sort of expected.



Very nice



Will work out a new foot solution to this...

Didn't you 3DP one of those feet sometime ago?
Don't know why, but that rear foot always seems to crumble, on that type of case, the front one for the tilting bail, must be made from a different plastic.

David

I probably did. Can't remember that far back. I blocked my escapades in 3d printing out of my mind so I don't go down that rabbit hole again. Then again, never know what might happen 

Beanflying & VK5RC have done 3DP replacements, they are listed in the 3DP parts thread under 5300A, 5300B & 34702A.
https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2255136/#msg2255136
https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg2472369/#msg2472369

David

Excellent. Many thanks. Bookmarked.

May buy another 3DP when I've moved. Got an excuse now.

[mnementh]

...So yeah, I HATE those trimmers too !    

Looks like a job for 3DP to me. Setting aside the plastic rot you describe (yuckyputz!  ), I quite like the beefy ceramic substrate I'm seeing there. I'd try to find a way to fix them.

mnem

I think it might be easier (and more durable/reliable) to just cut the missing/broken shaft in a skinny metal rod, drill a tiny hole in the center of the knob and press fit the rob into the knob. 

But the problem remains that the original design is flawed, in that there is nothing that keeps the shaft/knob from lifting out of the bore in the trimmer/ceramic base. Shaft does not "clip" into the trimmer. It's just a smooth skinny cylindrical shape. It holds into the bore merely thanks to interference. There is nothing to ensure "clamping" force onto the knob to make sure the wiper is making a good reliable contact with the track on the ceramic base. So if one could implement such a mechanism, that would be a nice improvement.

Obviously in practice it's not worth the trouble, so long as modern replacements are available, and at a reasonable cost.

But I guess as an exercise, just for the fun of it, yes you could try to make something with your 3D printer(ssss)...

My thought was more along the lines of dealing with the whole knob being crumbly. First thought was to print a new knob with a hole that could accept a m2 screw installed from the back of the ceramic base. Make it without stops so you just hold the screw with pliers and spin the knob on til it's snug.

But if it's easily replaced with 0.100" spaced 10-turn trimpot as Terra suggests, that's probably the simplest solution.

mnem
 

[mnementh]

What a nice hack for cleaning soldering pads on a pcb:

https://youtu.be/KDVu06WySjg?t=397

Agreed, neat trick.

(Too long; can't be bothered to watch): Cut a wedge out of high temperature resisting silicone rubber, put it into a [improvised] holder, and use the edge of the wedge to squeegee/wipe solder off pads after heating them to above melting point.

Not the first time I've seen this trick; there was a Hakko soldering video where the author demonstrated using the edge of the silicone rubber "oven mitt" to squeegee solder away in similar fashion. Easily a decade ago. 

mnem
*tssssst*

[factory]

I will make amends. My purchase rate of TE is higher than ever 

I got rid of the 7L12 because quite frankly it scared me. It could literally turn into a brick at any moment with no hope of repair. There are literally no parts mules for it or anything.

Looking at the pile of SA crap I got at the last PP auction, the HP 8557/8/9 SA plug-ins aren't any better, the same mechanical parts, switch wafers & knobs are broken/missing on most of them.
Clearly the mixer, Yig oscillator and attenuator are trouble too, judging by them either being missing or labelled as futzed, though I suspect some of that might have been the operators fault. 

David

Yes same with the SA's that were floating around today. I enquired about a couple. I was being pushed a 20GHz one for £60 and told what a good deal it was. But it came with a printed manual in a tesco carrier bag and a little zip lock bag taped on the front with some HP leaf contacts in it. He said he'd tried to repair it but not got around to finishing it. My daughter who was with me today actually laughed slightly too loudly at that. I passed on it.

Yes probably best avoided (unless in perfect condition & fully working), I should have mentioned turning one of the controls and there was the sound of one dropping off. 
The 400ish page PDFs put me off doing anything with the most complete one, shame they didn't come with any manuals, the joblot of 141 series SA plug-ins (in similar condition) did at least come with some. Oh that & the corrosion of the gold plated traces, some of which are used for those rotary switches.
Much prefer the older 141 series SA.

David

[bd139]

I will make amends. My purchase rate of TE is higher than ever 

I got rid of the 7L12 because quite frankly it scared me. It could literally turn into a brick at any moment with no hope of repair. There are literally no parts mules for it or anything.

Looking at the pile of SA crap I got at the last PP auction, the HP 8557/8/9 SA plug-ins aren't any better, the same mechanical parts, switch wafers & knobs are broken/missing on most of them.
Clearly the mixer, Yig oscillator and attenuator are trouble too, judging by them either being missing or labelled as futzed, though I suspect some of that might have been the operators fault. 

David

Yes same with the SA's that were floating around today. I enquired about a couple. I was being pushed a 20GHz one for £60 and told what a good deal it was. But it came with a printed manual in a tesco carrier bag and a little zip lock bag taped on the front with some HP leaf contacts in it. He said he'd tried to repair it but not got around to finishing it. My daughter who was with me today actually laughed slightly too loudly at that. I passed on it.

Yes probably best avoided (unless in perfect condition & fully working), I should have mentioned turning one of the controls and there was the sound of one dropping off. 
The 400ish page PDFs put me off doing anything with the most complete one, shame they didn't come with any manuals, the joblot of 141 series SA plug-ins (in similar condition) did at least come with some. Oh that & the corrosion of the gold plated traces, some of which are used for those rotary switches.
Much prefer the older 141 series SA.

David

Yes the 141T was more "Apollo Era Engineering" as I call it. If I was to grab an SA it'd be a bang up to date one (that doesn't go rusty like one vendor) or a 141T. So probably the 141T and a hernia it is.

They keep turning up for affordable amounts and I quite fancy having a go at one.

[factory]

No luck for me on ePay lately....

Well I got outbid on the hp 5090B receiver. 
I didn't mention it the other day, but the 5090 was supposedly the first hp TE designed in the UK, they seem quite uncommon too, though maybe a bunch of modified ones will appear on the bay, as spares/repair once the LW radio signal finally becomes EOL. 


Also tried to bid on a hp 185B oscilloscope that would have ended Friday at 11.30am, no bids all week, so I though no one else was interested (like the one in Germany that went for a single digit € a while ago). I was working when it ended and snuck away from the BDNL* to bid a ten minutes prior to the end, only to find the ePay mobile programme wouldn't accept my bid  turns out it sold on an offer about an hour or two before the end. This might or might not have been a good thing, as it was advertised as a "barn find" with minimal pictures and the sellers other "barn finds" looked in quite poor condition. 


*big dirty noisy lathe

David

How much did you bid on the 5090B? I have a 5090A and a B that I was going to use as parts donors.

My final bid was £60, it only had one other bidder.
It was however in much nicer condition than the B I have, plus still had feet & the correct (ancient) power cord, never seen the recorder option before, assuming it was an option & not something bodged on.
I do have a set of parts for the Radcom mod somewhere, just be-aware that the PSU rails are -V and I think the mod required +V, this might be why someone smoked the PSU in mine trying to modify it (not the Radcom mod).

David

[factory]

Random web search find for TE feet (searched for tilting bail), found these Hammond feet & bail sets, they look very much the same as those used on old Systron Donner, Eldorado, Wavetek, Hickok and probably some other US TE brands, the tilting bails are available in three lengths.

https://www.hammfg.com/electronics/small-case/accessories/1427d



David

[Cerebus]

This might be basted on their own testing.

I now have a mental image of someone conducting thermal testing of some kit by ladling hot fat over it in a roasting tray. 

[tggzzz]

My original copy of it I stole from the local library but they sent me a postal shit-o-gram with a large fine so I handed it back on an amnesty day about a year later 

I had a slightly different trick.

The senior library staff mentioned to my parents that I was borrowing books from the adult library on my junior library ticket, and maybe I would like a senior library ticket. My parents didn't let on that I had spotted that juniors didn't pay fines

[m k]

Midnight, somewhere.

[tggzzz]

I blocked my escapades in 3d printing out of my mind so I don't go down that rabbit hole again. Then again, never know what might happen 

Any printer at home is a rabbit hole. But OpenSCAD + Shapeways/DirtyPCBs isn't deep enough for rabbits.

[mansaxel]

That's a rather colourful Tant you have here ! So far I had only seen them yellow orange red or blue, now I see they even exist in flashy green.
Soon we can make a rainbow out of them.

Any other colours I am not aware of ?! 

Charcoal black. 

I also have "Rainbow striped, with a black hole" 

The "broken caps" ziplock bag is getting to be quite big at the moment. Mostly consists of Frako electrolytes, some with a strong urge to fly, as can be witnessed from their desire to push the bottom bung out...

[tggzzz]

I will make amends. My purchase rate of TE is higher than ever 

I got rid of the 7L12 because quite frankly it scared me. It could literally turn into a brick at any moment with no hope of repair. There are literally no parts mules for it or anything.

Looking at the pile of SA crap I got at the last PP auction, the HP 8557/8/9 SA plug-ins aren't any better, the same mechanical parts, switch wafers & knobs are broken/missing on most of them.
Clearly the mixer, Yig oscillator and attenuator are trouble too, judging by them either being missing or labelled as futzed, though I suspect some of that might have been the operators fault. 

David

Sounds like the HP MDA / Time Interval Analyser I got from PP. That rapidly turned into a pile of metal-for-any-use and an 80111 10MHz OCXO. So I broke even

[Robert763]

I will make amends. My purchase rate of TE is higher than ever 

I got rid of the 7L12 because quite frankly it scared me. It could literally turn into a brick at any moment with no hope of repair. There are literally no parts mules for it or anything.

Looking at the pile of SA crap I got at the last PP auction, the HP 8557/8/9 SA plug-ins aren't any better, the same mechanical parts, switch wafers & knobs are broken/missing on most of them.
Clearly the mixer, Yig oscillator and attenuator are trouble too, judging by them either being missing or labelled as futzed, though I suspect some of that might have been the operators fault. 

David

Yes same with the SA's that were floating around today. I enquired about a couple. I was being pushed a 20GHz one for £60 and told what a good deal it was. But it came with a printed manual in a tesco carrier bag and a little zip lock bag taped on the front with some HP leaf contacts in it. He said he'd tried to repair it but not got around to finishing it. My daughter who was with me today actually laughed slightly too loudly at that. I passed on it.

Yes probably best avoided (unless in perfect condition & fully working), I should have mentioned turning one of the controls and there was the sound of one dropping off. 
The 400ish page PDFs put me off doing anything with the most complete one, shame they didn't come with any manuals, the joblot of 141 series SA plug-ins (in similar condition) did at least come with some. Oh that & the corrosion of the gold plated traces, some of which are used for those rotary switches.
Much prefer the older 141 series SA.

David

Yes the 141T was more "Apollo Era Engineering" as I call it. If I was to grab an SA it'd be a bang up to date one (that doesn't go rusty like one vendor) or a 141T. So probably the 141T and a hernia it is.

They keep turning up for affordable amounts and I quite fancy having a go at one.

If you have used a more modern SA with direct frequency entry and digital storage you will not want to go back to a 141T. If you have space for a 141T think about a HP 8568A/B  or 8566 if you need micrware. They are reasonably repairable and fairly high performance.

[tggzzz]

OK, so my haul was

• a Fluke 515a portable calibrator for £20. Quick check shows Vdc excellent, µVdc cockeyed, resistors good, Vac not bad, missing the unique front panel switch
• three Muirhead decade resistors for £5. Looks good.
• Cropico 4 decade resistor box. A few resistors o/c, but can be replaced
• and the thing below, which is probably as near as I will get to having a slice of the one lying around in my first job

Ooh submarine telephone cable?

Yup.

The one in the lab was 3m of TAT-7, the last transatlantic coax cable. 61.8ohms impedance.

I'm going to try to measure the impedance of that cable with my Tek1502.  The challenge will be making an acceptable connection (i.e. better than croc clips). I have an idea for using my favourite 50ohm scope probe in both directions

[tggzzz]

OK, so my haul was

• a Fluke 515a portable calibrator for £20. Quick check shows Vdc excellent, µVdc cockeyed, resistors good, Vac not bad, unlikely the NiCd battery works, missing the unique front panel switch which I'll probably have to "improvise"
• three Muirhead decade resistors for £5. Looks good.
• Cropico 4 decade resistor box. A few resistors o/c, but can be replaced
• and the thing below for £5, which is probably as near as I will get to having a slice of the one lying around in my first job

Excellent. Glad to see the 515A went to the right person.

As for the cable, that's a great ornament 

It will go nicely alongside natural lava rocks that float on water, chicken eggs, the coffee mugs I posted earlier, interestingly broken bits of cars, and Black Forest treen. All in a pharmacist's dispensing cabinet, so I don't need to dust any of it

As for the right person: no (I already have a 515) repeat yes (I have a knob to copy).

[bd139]

If you have used a more modern SA with direct frequency entry and digital storage you will not want to go back to a 141T. If you have space for a 141T think about a HP 8568A/B  or 8566 if you need micrware. They are reasonably repairable and fairly high performance.

I used to use (and program) an 8593E. Well aware of the more modern ones.

For tinkering the analogue ones are better 

[med6753]

Attended my Grand Daughter's HS graduation party today. Good time by all. I called it ahead of time that the battle axe ex would not show up. Hate it when I'm right. My Son is pissed and rightfully so. I feel it's just as well. She's a nasty old bitch. It would have been a large (Yep, she fat) and dark cloud over the whole affair. She did sent flowers to the Grand Daughter. Big fucking deal.

Anyway, she's attending this college.....

https://www.champlain.edu/

Majoring in Computer Science. And here's the best part. FULL four year paid scholarship which does NOT require her to maintain a minimum grade point average. Is that a good deal or what? Told you she be smart. She takes after me. 

And I blew my carb intake to hell and back and I don't care.       
 

[dl6lr]

The "broken caps" ziplock bag is getting to be quite big at the moment. Mostly consists of Frako electrolytes, some with a strong urge to fly, as can be witnessed from their desire to push the bottom bung out...

Frako : Fragwürdige Kondensatoren...

[bd139]

On the subject of capacitors, I notice that RIFA has earned its rightful reputation on Wikipedia of making exploding capacitors 

https://en.wikipedia.org/wiki/RIFA_%28manufacturer%29