Test Equipment Anonymous (TEA) group therapy thread

[kj7e]

HP 175 'scope near Mancester needs rescuing
www.ebay.co.uk/itm/203478052196?
£40

HP 175 was my very first piece of HP TE back when I was about 12 years old.   Another local Ham who became a great friend of mine gave it to me when he heard me talking on 10m to others how my Heathkit 10-12 didn't work well.

[Brumby]

Even I cant bring myself to suggest @Brumby (not that far from him) should chase this poor orphan, no probes and already done to death by likely any trash handheld gimmick scope on evilbay is it already over priced at $0.99  eBay auction: #203469404981

This went off 11 hours ago for $32.88 - which was above what I was prepared to put in.  I already have more than one scope that can fulfill a role as a henchman, so I'm not too concerned at all.

To offset this (minor) disappointment, an order from Aliexpress found its way to me .... finally.  A bulk order of 50 of these (in a mix of colours) that should see me out for the foreseeable future (and then some):


When I started putting the order together, I just felt the need to stock up on a decent socket.

The middle unit shows how much thickness can be secured.  It's more than I could ever imagine needing.

[xrunner]

I finally got the Agilent E4411B spectrum analyzer flash memory and firmware upgraded after a little pain. If you're interested you can dive into it at this point -

https://www.eevblog.com/forum/repair/agilent-esa-e4401b-memory-(b72)-and-firmware-upgrade/msg3577246/#msg3577246

I applaud your application to the task - a heroic effort - me and firmware etc are not on talking terms! (I am the dumb part🙄)
Well done 👍

LOL yea that had me beat-down for a while, especially at the beginning when the damn thing wouldn't even read the first floppy disk with the loading program!  I searched the internet and never found any mention of how to get around that, so I had to come up with my own solution.

I still can't explain what that problem was (is). It was an adventure but I'm glad it's over now. 

[tautech]

Am currently bothered by a slightly leaking 3/4" cast iron union coupling in my computer cooling system. It did not leak before, but I had to break it open to fix a broken safety valve. Now, on reassembly, it leaks.

Mac union or a pipe socket ?
Taper or parallel threads ?

Parallel threads require a crush washer or Dowdy seal whereas for taper threads thread tape normally stops any weeps. You can use thread lockers but be sure to get the softest ones available with a 'wicking' rating for sealing threads.

Conical mating surface.  I needed an union to join two pieces of the piping where I could not use a normal threaded coupling. Normal tapered threads are actually quite easy to get water tight using flax (which we prefer here in place of hemp) and compound.

This is the one:



I'l do some tests with tightening it a bit more -- having an 18" adjustable spanner is an excellent argument against threads 

Also, perhaps a bit lapping compound on the surfaces might help.

Ok we know those as Mac unions here. There are flange unions too, IIRC Bean mentioned them earlier and they use a fiber or nylon washer to seal but don't have the same benefit of being able to be fitted misaligned.
Mac unions certainly need be reasonably clean and tight to seal and application of lube and/or anti-seize to resist corrosion is worthwhile.

Is it holding much pressure as a more modern nylon replacement might be suitable:

[mansaxel]

Ok we know those as Mac unions here. There are flange unions too, IIRC Bean mentioned them earlier and they use a fiber or nylon washer to seal but don't have the same benefit of being able to be fitted misaligned.
Mac unions certainly need be reasonably clean and tight to seal and application of lube and/or anti-seize to resist corrosion is worthwhile.

Is it holding much pressure as a more modern nylon replacement might be suitable:

It holds maximum 2 Bar -- or ~29 PSI. Will do some more tests. It's just a droplet every 5 minutes at 1,25 Bar as of now. 

[tautech]

2 bar is nothing, open, clean, lube and tighten it good and tight.

[tonyalbus]

Anybody here in need of some 250MOhm 1% 15kV Caddock resistors? NAWTS, as usual.

https://www.ebay.com/itm/402887007628
https://www.ebay.com/itm/402887007706

Looks like the sticks i give to my dog... he can't 'resist' them 

[BU508A]

Anybody here in need of some 250MOhm 1% 15kV Caddock resistors? NAWTS, as usual.

https://www.ebay.com/itm/402887007628
https://www.ebay.com/itm/402887007706

Looks like the sticks i give to my dog... he can't 'resist' them 

Ungh! 

Normally I am the flat joke commissioner here. 

[med6753]

The Type 454 PSU re-cap saga....

The A Sweep/Trigger board is moved out of way. Lots of pictures regarding the perimeter connections plus the excellent wiring pictorial. There are 4 cans to be removed with new caps on terminal strips. But it's going to be very tight and precise work.



In the meantime pulling out the other Type 454 and going to start pulling parts for Oculus and packing them for shipment. Not sure if I have a big enough box. 

J/K.   
 

[McBryce]

Anybody here in need of some 250MOhm 1% 15kV Caddock resistors? NAWTS, as usual.

https://www.ebay.com/itm/402887007628
https://www.ebay.com/itm/402887007706

Looks like the sticks i give to my dog... he can't 'resist' them 

I thought he'd have preferred Dog Bone Resistors?

McBryce.

[tonyalbus]

Anybody here in need of some 250MOhm 1% 15kV Caddock resistors? NAWTS, as usual.

https://www.ebay.com/itm/402887007628
https://www.ebay.com/itm/402887007706

Looks like the sticks i give to my dog... he can't 'resist' them 

I thought he'd have preferred Dog Bone Resistors?

McBryce.

I think its also for Cat... when you read out-loud...it clearly sounds like CatDog 

[mnementh]

   I cant believe someone threw this in the metal waste bin, from where I rescued it. Thankfully the VFD isnt damaged, quick wipedown and then a rough test > seems to be working.

PS: Except current, fails 600.1 and 600.2

I'd say that gets today's for sure... well snurched!!!

mnem
 

[Vince]

Another sad TEA day for me ! 

Missed again on a marvelous classic Tek ad today..... a couple weeks ago I missed near Parsi a cool dual beam 561 with it's external PSU and cable, 4 nice plugins and Tek cart for 50 Euros, ie pretty much given away.

Today an incredibly similar ad : again near Paris, again a nice 500 series, a 545B in pristine condition (have a 545A but really want a 545B !!!) again with its cart, and a nice one at that (with the extruded aluminium legs ! ), and 3 plug-ins, including....... a freaking 1L30 10GHz spectrum analyzer plugin !!!! 

All for 150 Euros ! Not free, but still 20% of the normal price, a massive bargain !

https://www.leboncoin.fr/equipements_industriels/1991447724.htm



Ad was posted this morning at 8H30, saw it 2H00 later at 10H30 Phone the guy immediately of course. I was hoping I might stand a chance because like 99% of people, he misspelled "Tektronix", so I was hoping it would fly below some people's radar. No such luck. Guy did answer the phone immediately which is cool, but asking " is that you Matthew ?? "....  uhhhh.... no, I am Vince not Mat... "Ah, sorry, a guy named Matthew left a message 30 minutes ago saying he wanted the scope !! sorry, have  a good day ! ".


HAVE A GOOD DAY ?!!!    is he kidding ?!

HOW CAN I HAVE A GOOD DAY WHEN I MISS.... AGAIN.... THAT KIND OF DEAL ?!!!!       

Wow..... so had I seen the ad and called just 35 minutes earlier, I would have been mine !!!!

no... missing two such incredible deals in a row, within a couple weeks, and missing them by 30 minutes or an hour.... it's too cruel, I am done with life...

GRRRR !!!!!   


So the moral is :

1) there ARE still good deals to be found these days
2) You CAN have them.... IF YOU CHECK THE SITE EVERY 20 minutes all day long !!!!!

So I will try to do that... but my smartphone is old and slow, takes 30 seconds to react to any input on the website it's unbearable. Need to get a better smartphone that can surf the web with decent responsiveness.... budget 75 Euros max for a used one. Can get brand new ones for that price, but don't know how they perform on the web. Android/Linux only please. Removable battery with SD car and headphone jack. Thin and light. Screen large enough to surf the web comfortably, but small enough to fit in my large hand.

[med6753]

Wow, that Type 545B and plug-in's looked absolutely mint. Too bad you were late. 

[mnementh]

Ehhhh... it's just another fuckkin' ugly scope from the caveman days. Who fucking cares...?   

mnem
Yes, I would dump a jar of scorpions out in a lifeboat just to see who could swim...

[mnementh]

Am currently bothered by a slightly leaking 3/4" cast iron union coupling in my computer cooling system. It did not leak before, but I had to break it open to fix a broken safety valve. Now, on reassembly, it leaks.

Mac union or a pipe socket ?   Taper or parallel threads ?

Parallel threads require a crush washer or Dowdy seal whereas for taper threads thread tape normally stops any weeps. You can use thread lockers but be sure to get the softest ones available with a 'wicking' rating for sealing threads.

Conical mating surface.  I needed an union to join two pieces of the piping where I could not use a normal threaded coupling. Normal tapered threads are actually quite easy to get water tight using flax (which we prefer here in place of hemp) and compound.

This is the one:      I'll do some tests with tightening it a bit more -- having an 18" adjustable spanner is an excellent argument against threads  Also, perhaps a bit lapping compound on the surfaces might help.

Ok we know those as Mac unions here. There are flange unions too, IIRC Bean mentioned them earlier and they use a fiber or nylon washer to seal but don't have the same benefit of being able to be fitted misaligned. Mac unions certainly need be reasonably clean and tight to seal and application of lube and/or anti-seize to resist corrosion is worthwhile.

Is it holding much pressure as a more modern nylon replacement might be suitable:   

Hmmm... IME, at least over here, those usually have a hemispherical bronze seat ring and the opposing surface is  tapered/conical. Good for whatever pressure the schedule rating in the casting says; schedule 40 & 80 are common. Schedule 200 usually have a different construction; forged with either multiple sealing contact areas or a replaceable copper washer.

mnem
IME, YMMV, DQMOT, DILLIGAF...?

[mnementh]

Anybody here in need of some 250MOhm 1% 15kV Caddock resistors? NAWTS, as usual.

https://www.ebay.com/itm/402887007628
https://www.ebay.com/itm/402887007706

Looks like the sticks i give to my dog... he can't 'resist' them 

Ungh! 

Normally I am the flat joke commissioner here. 

Blearrgh... yeah, that was bad.  Soggy ol' boots are in the cupboard over there; please flog yourself appropriately Tony...

mnem
...and don't forget to put them away so they're ready for next customer! 

[mansaxel]

Hmmm... IME, at least over here, those usually have a hemispherical bronze seat ring and the opposing surface is  tapered/conical.

This one's steel all through. I have a few more tricks up my sleeve, though. I think I did miss a few degrees
on the straightness, and that will punish, harshly.  Also, is fixable.

[xrunner]

Another sad TEA day for me ! 

Missed again on a marvelous classic Tek ad today..... a couple weeks ago I missed near Parsi a cool dual beam 561 with it's external PSU and cable, 4 nice plugins and Tek cart for 50 Euros, ie pretty much given away.

Today an incredibly similar ad : again near Paris, again a nice 500 series, a 545B in pristine condition (have a 545A but really want a 545B !!!) again with its cart, and a nice one at that (with the extruded aluminium legs ! ), and 3 plug-ins, including....... a freaking 1L30 10GHz spectrum analyzer plugin !!!! 

Sad for me too. I'll never see that spectrum analyzer plug-in in operation now. 

[Cerebus]

Even I cant bring myself to suggest @Brumby (not that far from him) should chase this poor orphan, no probes and already done to death by likely any trash handheld gimmick scope on evilbay is it already over priced at $0.99  eBay auction: #203469404981

This went off 11 hours ago for $32.88 - which was above what I was prepared to put in.  I already have more than one scope that can fulfill a role as a henchman, so I'm not too concerned at all.

To offset this (minor) disappointment, an order from Aliexpress found its way to me .... finally.  A bulk order of 50 of these (in a mix of colours) that should see me out for the foreseeable future (and then some):


When I started putting the order together, I just felt the need to stock up on a decent socket.

The middle unit shows how much thickness can be secured.  It's more than I could ever imagine needing.

I've used those before and they're not too bad - certainly better than most binding posts that come out of the Middle Kingdom and, to my personally aesthetic senses, the grey with colour accent looks much nicer than solid colours. Funnily enough I've been meaning to make a bulk order for stock; last time I found some nice grey binding posts they stopped being made (a consequence, as I recall, of the acquisition/merger of multicontact).

[Vince]

Another sad TEA day for me ! 

Missed again on a marvelous classic Tek today..... a couple weeks ago I missed near Parsi a cool dual beam 561 with it's external PSU and cable, 4 nice plugins and Tek cart for 50 Euros, ie pretty much given away.

Today an incredibly similar ad : again near Paris, again a nice 500 series, a 545B in pristine condition (have a 545A but really want a 545B !!!) again with its cart, and a nice one at that (with the extruded aluminium legs ! ), and 3 plug-ins, including....... a freaking 1L30 10GHz spectrum analyzer plugin !!!! 

Sad for me too. I'll never see that spectrum analyzer plug-in in operation now. 

Maybe you will one day... I have tracked a 1L20 one, the 4+ GHz version.

2 years ago I bought my first 547 and my 545A from an old retired dentist 400kms away from me. Had some more interesting Tek stuff which I could not afford to buy at the time, mostly several cool plug-ins, including a 1L20 !!!! He even showed it to me working, on his 545A... brought the 545A with me but could not afford all the plugins. He said he would keep them for me. That was 2 years ago. We kept in touch since then. I kept him informed of my misfortunes with regards to my house builder,  which totally prevented me from buying anything. He was very understanding, said no worries I will keep all your Tek stuff !

A really nice old man.  But I am worried I may lose all these nice plugins... e-mailed him over a month ago, no reply. Again a few days ago... still no joy.
He was going through a big medical problem, recovering from heart surgery performed late last year. At his age (70++), it's never good... I hope he is still OK ! 

I have long lost his phone number and street address. I do have his name of course, so could try to look it up. Also remember how to get to his house, so could look up at least the name of the street from Google Maps... really need to give him a call to make sure he is alright ! Hopefully it won't be his wife answering, saying he passed away ! NOOOOOOOOO !!!! 

[capt bullshot]

In the aftenoon, during a 2h teams call, I had some time to adjust that Datron 1041 (Thanks to DC1MC again).
Followed the full procedure as written in the manual, now it's spot on
Interestingly, there's some pots to adjust on the digital board before one is supposed to adjust the input. It's called "Preliminary DC Isolator Board adjustments" and "Digital Board scale adjustments". After having done these adjustments, most ranges were quite near spot on, so only little adjustment was necessary at the "DC Isolator Board full range adjustments".
Another interesting fact: AC and Ohms range are options with this instrument, but none of them is fitted, though all the required front panel buttons are there. And it's got binding posts labelled "I+" and "I-", presumably meant for current measurement, but there apparently there's no current measurement option nor buttons to select.



Still wondering what's the answer to the question "20.00mA or 20.32mA?" Especially written onto an instrument without an amps range

[Neomys Sapiens]

In the aftenoon, during a 2h teams call, I had some time to adjust that Datron 1041 (Thanks to DC1MC again).
Followed the full procedure as written in the manual, now it's spot on
Interestingly, there's some pots to adjust on the digital board before one is supposed to adjust the input. It's called "Preliminary DC Isolator Board adjustments" and "Digital Board scale adjustments". After having done these adjustments, most ranges were quite near spot on, so only little adjustment was necessary at the "DC Isolator Board full range adjustments".
Another interesting fact: AC and Ohms range are options with this instrument, but none of them is fitted, though all the required front panel buttons are there. And it's got binding posts labelled "I+" and "I-", presumably meant for current measurement, but there apparently there's no current measurement option nor buttons to select.



Still wondering what's the answer to the question "20.00mA or 20.32mA?" Especially written onto an instrument without an amps range

Regarding the I+ and I- terminals: I think that is their notation for the current source in the 4-wire resistance measurement function. The grouping with 'Ohms guard' seems to support that.

Nice divider, BTW.

[Neomys Sapiens]

On calipers,
I was using mine today. The Efratom FRK oscillator project is progressing slowly. I was looking at the mounting screws. They need to be longer because there is now the rear panel of the case between the oscillator and heatsink. The screws are pretty small. I looked at the manual and there is a defect right through the screw size. It looks like 2.6mm which is a bit of an odd size. I then looke at the Racal standard the uses the FRK. It calls up M2.5. So I measured the screws in the unit that are probably original. They are clearly M2.5 (mjor dia 2.380 to 2.480) not M2.6 (2.480 to 2.980). However they are loose in the tapped holes in the unit.
Both M2.5 and M2.6 are 0.45mm pitch as standard (0.35 option) so I've ordered some M2.6 cap heads. Usefully they are used on some model helicopters so are available.
I have several sets of calipers from cheap innacurate digital ones just used fror marking out through to 12" Mitutoyo and micromoters, height gauges and slip gauges. The calipers in the photo are my everyday mid-range ones from ARC Eurotrade  costing about £25 Highly recommended, They even do imperial fractions.
https://www.arceurotrade.co.uk/Catalogue/Measurement/Calipers/Digital-Calipers-150mm-300mm-6-12

M2.5 is a "preferred size", M2.6 is not. The next up preferred size is M3.0. Why, oh why, would someone pick M2.6 as a size? In terms of any property a screw needs (UTS, clamping force, etc.) they're indistinguishable for all practical purposes. In any sensible table of metric screw sizes you won't even find any entries except for preferred sizes.

My suspicion is that it's them folks deeply wedded to the imperial system, but forced to "go metric" for reasons beyond their personal control. Someone sticks a finger in the air and decides that a screw needs to be "about \$\frac{1}{10}\$". They open up Machinery's Handbook, scan down a table of metric thread sizes and pick, by calculation, the first that's greater than 0.1". It has to be something like that because if you picked a #3 screw (basic size 0.0990" = 2.5146mm) when hunting for the closest metric equivalent you'd come up with M2.5 (basic size 0.0984"), and if you'd picked a #4 (basic size 0.1120" = 2.8448mm) you'd either pick a bastard size of M2.8 or M2.9, or the sensible M3.0.

M2.3/2.6/2.8 was a formerly preferred series. It did not make it into the ISO.
Now anything should be 2.0/2.5/3 and that's it. But they survive longer than intended.
Which is a bitch specially with 2.5 and 2.6, as they can't be kept apart visually.
In this case, you need vernier calipers to sort your screws.

That was always a problem with DIN  versus Japanese "metric" screws.
Not only that, but the DIN ones  all had a finer thread pitch.

Is ISO also the culprit for the disappearance of a bunch of really useful DIN coax connectors?

I have a lot of salvaged cables, & a directional coupler, all with "spinner" connectors.

I managed to swap the output connector on the coupler for an "N" but the others were more difficult.
I have one "N", & a couple of "BNC" to spinner adaptors for the ports, so not so bad there, but there are also detectors to sit on those ports, which I'd like to use.
The demodulated outputs from these appear on what we used to call " Siemens coax sockets" in Telecom Australia.

We used these & the audio ones from the same stable extensively back in the day, but now them & the matching plugs are "unobtainium".

I bought two "Siemens" coax "links"  at a hamfest, but they need mods to use as standalone plugs..

If you can furnish either dimensions or a picture (preferably with a size reference) of those 'Spinner' connectors, the chances are good that I can tell you their real designation and current status!

[capt bullshot]

Regarding the I+ and I- terminals: I think that is their notation for the current source in the 4-wire resistance measurement function. The grouping with 'Ohms guard' seems to support that.

Yes, 4W Ohm uses these posts. I've got an 1061, it's got the same labeling for the terminals. But it's got an ampere range too, using the I+ and I-.