Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

mnem
I quite like this version better...

[Vince]

Carlson just posted a new video, a lovely old HP counter :



Am well impressed with the density of tubes in the thing, as much as high-end 500 Tek scopes but in less than half the volume 

Yes I know, it counts only up to 100kHz or so, is super old from 1957, yet.. it has a BNC input socket ! 

But it's an HP, it was expensive so they could do whatever they wanted.... old Metrix stuff was sold much cheaper no doubt...

[Specmaster]

And let's not talk about GR connectors. What a nightmare they are. 

Aren't they basically a slightly modified Belling-Lee connector?

[Specmaster]

<snip>
Stop shouting, shouty people get washed down with the slops bucket.

OK, will now stop shouting I only started in case Vince was having difficulty reading and digesting smaller fonts.

[mnementh]

*snerks IRL*   Oh, now you're just agitating...

mnem
 

[Robert763]

Found some Tume nuttery stuff at the back of the garage. A Racal 9478 distribution amplifier with OCXO in it.  An EES 0210  MSF receiver/clock. I can't find any info on this. The name European Electronic Systems seems to have been taken over. need to do some investigation. Starting with the antenna socket to see if it has DC on it which would indicate it needs an active antenna.
Also two Odetics SatSync 325 GPSDOs  One with a Rb oscillator and all the options but a early GPS engine that needs a downconverting active antenna. I have a spare set of boards and I think the updated GPS RX in the attic. I'll have to dig them out. The Rb in the one without a usable GPS is a Efratom FRS-C. This unit owes me nothing. It was part of a HAVE-QUICK shipboard master timing transmitter. It had an AN/ARC-164 UHF panel mount transceiver as well as the GPSDO and other equipment in a 19" rack case. I bought it at a direct military surplus tender sale. Selling the ARC-164 made a good profit so the rest was pure bonus. If I don't have an spare updated GPS receiver module to fit in it I'll just extract the FRS-C Rb. I might transfer the timecode option board to the other unit too. The SatSync was a high performance unit in its day but is large by modern standards. Anyone want a 3U GPSDO?

[Robert763]

I also found a box of old Psion Organiser stuff. There are eight organisers from a II XP to a Siena. Plus leads and books. The oldest is over 35 years old and they all still work. The oldesrt still has data in it. I doubt many modern handheld devices will work at and retain data after 35 years including 14 at the back of an unheated garage!

EDIT: I consider the Psion II test equipment. When equipped with the RS232 lead I have used them for data logging and comms link debugging.

[Vince]

I am stilll amazed at how you have so much stuff in your garage that you are genuinely surprised when you see much of it, no matter how cool or expensive or fancy : "Oh, didn't remember I had all that !! ".

I wish I had that kind of problem ! 


For now I am tying to order some BNC - BNC test leads but can't make sense of the subtleties between the various acronyms/norms used to describe them. I am wondering if these norms somehow have a relation ship to the physical presentation of the cable. That is, I don't want the very thick/big diameter black one, I prefer the thin black ones.  Looking at Farnell's offering, pictures and pictures of lots of their cables, I am starting to venture into thinking that the (vanilla) RG58 is the cheaper stuff of all, and has the very thick black form.

The RG58 U and / or C might look like the are black too, but thinner / more flexible.  It seems to be about twice the price of the thicker RG58.

RG316 however clearly (pun intended) seem to the modern super thin transparent cable that we see all over the place. Price wise it seems to be 3 times the price of the thick RG58.

Is that right or does that have nothing to do anything ?! 

It's still 2021 here for now...

[factory]

Carlson just posted a new video, a lovely old HP counter :



Am well impressed with the density of tubes in the thing, as much as high-end 500 Tek scopes but in less than half the volume 

Yes I know, it counts only up to 100kHz or so, is super old from 1957, yet.. it has a BNC input socket ! 

But it's an HP, it was expensive so they could do whatever they wanted.... old Metrix stuff was sold much cheaper no doubt...

The 524A dates back a bit further to 1952; https://www.hpmemoryproject.org/wa_p..._a_page_11.htm
Mil version of the 524B here;

Presumably prices of any HP 52x counters will go up to stupid levels, now Carlson has done a video, not that they are easy to find over here in the first place.
Got to say I skipped through most of the Carlson video.

David

[factory]

And let's not talk about GR connectors. What a nightmare they are. 

Don't know what your talking about, I was using some the other day between the 5340A & 8616A, I do have some N cables but the GR cable & adaptors were easier to locate.


David

[Specmaster]

For the very last tool purchase in 2021 I have got myself one of these from Amazon, and no Mnementh, I didn't copy you as I actually ordered these last night (Thursday) and they will be with me on the 2nd Jan.

SWMBO is getting slightly fed up with the internet connection in the living room dropping out which I think is because there are a couple of plugs in the mini switch inside the TV cabinet that have had their tongues broken off so no longer securely clip-in, so I'm going to fit new plugs.

I'm going with the through type of plugs to ensure that the correct cables are in the right positions before crimping as I've never really learnt the knack of getting the wires into the correct slots on the standard plugs. Does anyone else have the same problem?

[tautech]

I'm going with the through type of plugs to ensure that the correct cables are in the right positions before crimping as I've never really learnt the knack of getting the wires into the correct slots on the standard plugs. Does anyone else have the same problem?

Used to until I watched how our ISP buddy does it.
Overstrip and manipulate the strands into their correct positions and flex and tweak them between thumb and forefinger until they are all nice and straight and behaving themselves.
Then snip to correct length and offer up the RJ45 plug which should initially slide on with little effort however getting them all the ways home might take a bit of wiggling and shoving.

Did a couple the other day after not having done any for years and they worked out mint. 

[mansaxel]

No test equipment was harmed in the making of dinner tonight. But I used my kitchen scales, aggressively.

@Zucca: (I'm a barbarian and I have fruit in my panna cotta.)

[ Specified attachment is not available ]

It's the last of the bottles we brought home from Italy in 2019. Now we must go back and pick up some more.

[Vince]

Carlson just posted a new video, a lovely old HP counter :



Am well impressed with the density of tubes in the thing, as much as high-end 500 Tek scopes but in less than half the volume 

Yes I know, it counts only up to 100kHz or so, is super old from 1957, yet.. it has a BNC input socket ! 

But it's an HP, it was expensive so they could do whatever they wanted.... old Metrix stuff was sold much cheaper no doubt...

The 524A dates back a bit further to 1952; https://www.hpmemoryproject.org/wa_p..._a_page_11.htm
Mil version of the 524B here;

Presumably prices of any HP 52x counters will go up to stupid levels, now Carlson has done a video, not that they are easy to find over here in the first place.
Got to say I skipped through most of the Carlson video.

David

Wow that military version looks even cooler  ! An extra decade, a magic eye tube, and two beautiful round galvanometers ! I just love these old round ones, I wish I could find a place that sells them !
I once stumbled across a modern Chinese reproduction on Ebay but it looked crap/cheap, they didn't put enough effort into it...
For starters they used Pozidrive screws to hold the scale in place, rather than period looking slotted heads. It just screamed at me when I saw it ! 

[Vince]

For now I am tying to order some BNC - BNC test leads but can't make sense of the subtleties between the various acronyms/norms used to describe them. I am wondering if these norms somehow have a relation ship to the physical presentation of the cable. That is, I do'nt want the very thick/big diameter black one, I prefer the thin black ones.  Looking at Farnell's offering, pictures and pictures of lots of their cables, I am starting to venture into thinkinh that the (vanilla) RG58 is the cheaper stuff of all, and has the very thick black form.

The RG58 U and / or C might look like the are black too, but thinner / more flexible.  It seems to be about twice the price of the thicker RG58.

RG316 however clearly (pun intended) seem to the modern super thin transparent cable that we see all over the place. Price wise it seems to be 3 times the price of the thick RG58.

Thinking out loud in case some silnet lurkers might be interested in the subject as well...


Just looked at Wikipedia, they have a page about the various coax cable types, loads and loads of them. A nice table summarizing everything is provided :

https://en.wikipedia.org/wiki/Coaxial_cable

So looks like the " RG" XYZ acronym  does indeed code some aspectcs of the cables.

RG58/U is given for 5mm ouside diameter and PE dielectric material.

RG 316 the thin transparent stuff is given as 2.6mm diameter, and PTFE dielectric material.

So look like RG58 is by default the very thick cable type. But looking at pictures on Farnell, some of these RG58 look thinner than others...
Need to dig deeper into the various variations of the RG58 , with these 'U' and/or 'C' suffixes, see if they command a different outside diameter or god knows what.


EDIT :

Found this :

https://service.shure.com/s/article/rg58-a-u-b-u-c-u?language=en_US

Looks like the ' U ' is always next to the A/BC letter. It's always A/U or C/U.
Says that A/C all have the same outside diameter... I guess this is fixed due to the dielectric material used that's the same for all RG58 cables, so in order to get the required impedance, it has to be a certain thickness and nothing else... well just a shot in the dark.
"Regular" RG58 has a solid core conductor. 'A' or 'C' have a flexible/stranded conductor, so more flexible (might want that then...). 'C' also has a different material for the outside jacket, as they say.  I guess probably to make it more supple/flexible ?
So looks like I can't have a thin RG58, but I can have a flexible one i I buy RG58 C/U ...

Still, my scope probes have very thin and flexible cable, like the transparent stuff but black... so I guess this means it must be yet another RG-XYZ norm again ? Which one ?

Must be someone who knows on here... don't be shy... help me buy nice cables so I don't waste my money on crappy super stiff cables 

The search continues...

[Specmaster]

I'm going with the through type of plugs to ensure that the correct cables are in the right positions before crimping as I've never really learnt the knack of getting the wires into the correct slots on the standard plugs. Does anyone else have the same problem?

Used to until I watched how our ISP buddy does it.
Overstrip and manipulate the strands into their correct positions and flex and tweak them between thumb and forefinger until they are all nice and straight and behaving themselves.
Then snip to correct length and offer up the RJ45 plug which should initially slide on with little effort however getting them all the ways home might take a bit of wiggling and shoving.

Did a couple the other day after not having done any for years and they worked out mint. 

I've watched many people do it on video before and I have managed to do it once or twice but only after ruining many plugs  maybe its because I have such big hands or something. When I was working, we used 6 core flat cable for our lighting control networking and never had any trouble terminating those, but make them into a circular cable and I struggle 

[factory]

I have to say I didn't check the caps on that board, only three two to check. The IC has been removed, I might try it in the HP logic comparator thingy tomorrow.

David

The decoupling caps tested fine, they used good quality axial tants.
Logic comparator says the 9312 IC removed from the A20 timebase board is dead, one in the switch inputs (pin 12) is stuck in one state.



After that I've been checking the PROMs on the A21 control board with the logic comparator (set in logic clip mode) & logic pulsar (with link W2 removed on A20), PROM 1816-0004 appears to be defective, output pin 1 is stuck low. Now I really need the redundant programmer from work, before they chuck it in a skip. 



Also while testing the PROMs, I noticed address 31 on the truth table repeats & alters the front panel display. I thought I would try the defective A23 count register board & compare what happens with the good board (while I wait for the ICs needed for the logic comparator to test A23).
With the good A23 board the & pulsing address 31, it blanks the display with the next five steps from MSD to LSD, then the display lights again & blanks the MSD on the next two steps, followed by filling with 7s/9s with the following steps from MSD to LSD.
The defective A23 board behaves differently, after the second step it skips the blanking steps and fills the display with 7s/9s with the following steps from MSD to LSD. Others have had problems with the shift register ICs on that board, on this one every one has been reworked in the past, along with a few others.



I've gone as far as I can with the faulty digital boards, until the replacement & test ICs arrive. Might take a break from the 5340A & troubleshoot the HF input another time.

David

[Robert763]

For now I am tying to order some BNC - BNC test leads but can't make sense of the subtleties between the various acronyms/norms used to describe them. I am wondering if these norms somehow have a relation ship to the physical presentation of the cable. That is, I do'nt want the very thick/big diameter black one, I prefer the thin black ones.  Looking at Farnell's offering, pictures and pictures of lots of their cables, I am starting to venture into thinkinh that the (vanilla) RG58 is the cheaper stuff of all, and has the very thick black form.

The RG58 U and / or C might look like the are black too, but thinner / more flexible.  It seems to be about twice the price of the thicker RG58.

RG316 however clearly (pun intended) seem to the modern super thin transparent cable that we see all over the place. Price wise it seems to be 3 times the price of the thick RG58.

Thinking out loud in case some silnet lurkers might be interested in the subject as well...


Just looked at Wikipedia, they have a page about the various coax cable types, loads and loads of them. A nice table summarizing everything is provided :

https://en.wikipedia.org/wiki/Coaxial_cable

So looks like the " RG" XYZ acronym  does indeed code some aspectcs of the cables.

RG58/U is given for 5mm ouside diameter and PE dielectric material.

RG 316 the thin transparent stuff is given as 2.6mm diameter, and PTFE dielectric material.

So look like RG58 is by default the very thick cable type. But looking at pictures on Farnell, some of these RG58 look thinner than others...
Need to dig deeper into the various variations of the RG58 , with these 'U' and/or 'C' suffixes, see if they command a different outside diameter or god knows what.


EDIT :

Found this :

https://service.shure.com/s/article/rg58-a-u-b-u-c-u?language=en_US

Looks like the ' U ' is always next to the A/BC letter. It's always A/U or C/U.
Says that A/C all have the same outside diameter... I guess this is fixed due to the dielectric material used that's the same for all RG58 cables, so in order to get the required impedance, it has to be a certain thickness and nothing else... well just a shot in the dark.
"Regular" RG58 has a solid core conductor. 'A' or 'C' have a flexible/stranded conductor, so more flexible (might want that then...). 'C' also has a different material for the outside jacket, as they say.  I guess probably to make it more supple/flexible ?
So looks like I can't have a thin RG58, but I can have a flexible one i I buy RG58 C/U ...

Still, my scope probes have very thin and flexible cable, like the transparent stuff but black... so I guess this means it must be yet another RG-XYZ norm again ? Which one ?

Must be someone who knows on here... don't be shy... help me buy nice cables so I don't waste my money on crappy super stiff cables 

The search continues...

The "RG" series of cable desigations are obsolete military specifications. RG-58 is 50 ohm nominal impedance. The C/U variant  has a stranded center conductor making it more flexible but slightly higher loss than the solid conductor variant.
RG58C/U is a good choice for general purpose coaxial test leads up to VHF frequency.
Note that very few of the cheap cables are made to the full specification. in particular the amount of copper in the screen is much lower. Unfortunatly you can't tell until you cut the cable. Unless the cable also has a known manufacturer's (e.g Belden) part number you don't know what it is. You generally get what you pay for.
Also as these cables use PVC and PE insulation they are not generally acceptable for fixed installations and are banned in aircraft due to fire, smoke and fume concerns.
The "modern" M17 series of cables witth PTFE FEP and similar insulation perform better generally but are not very flexible so not so good for test leads.

[Specmaster]

Stumbled across a video of my very first scope which I brought just after starting my first job in the 60's. It was on sale in a local electronics shop, one that also used to get hold of equipment that had been used in Marconi radio and television factory in New Street, Chelmsford, which is where my scope came from, it still their asset tag on it. If I recall correctly it cost me around £60 which was a lot of money in those days. It had a lovely blue trace and was a true dual beam jobbie, not a dual trace, so it was possible to display 2 frequencies at the same time. Does anyone know what the name was of those input connectors at all. I've never come across these since, and just after I got that scope, the new ones were coming out with BNC jacks on them. I had the scope for a couple of years and loved it but was disappointed when the main power transformer the black brick at the rear, just visible in the video, went kaput and the cost to replace it was something like £350 to have another made up, it went to the dump.

Later I got one of these Advance RF signal generators from the same source that also had the dreaded Belling-Lee coax sockets, but as these were pretty common at the time, I was able to source new replacements to replace the clapped ones on the generator, from the same shop that sold me the generator.

[Vince]

The "RG" series of cable designations are obsolete military specifications. RG-58 is 50 ohm nominal impedance. The C/U variant  has a stranded center conductor making it more flexible but slightly higher loss than the solid conductor variant.
RG58C/U is a good choice for general purpose coaxial test leads up to VHF frequency.
Note that very few of the cheap cables are made to the full specification. in particular the amount of copper in the screen is much lower. Unfortunately you can't tell until you cut the cable. Unless the cable also has a known manufacturer's (e.g Belden) part number you don't know what it is. You generally get what you pay for.

Thanks Robert.

Just found this table from the IDC, that says the letter suffix determines also the impedance...  with 'C' suffix being the only one that's actually 50ohms. Others are 52 or 53.5.

But since you say this is all obsolete and all RG58 sold these days is 50 ohms, that makes it easier...

So 'C' suffix seems the best choice then, at least to begin with... I have zero coax cables here, would you believe it, other than a crappy 75ohms RG59 cable I bought by mistake thinking it was 50ohms... old guy at the local electronics shop who sold it to me 4 years ago, swore it was 50 ohms, yeah....   

So I am looking at getting a few decent coax cables and various adapters to get me started in the lab. So many scopes and counters here, and not even cables and adapters to actually use them, how ironic 

OK so some RG58 C suffix should have me sorted, thanks, will go shopping on Farnell's site... will get something decent. They sell TE Connectivity or Amphenol mostly, should be decent hopefully.

00.02 here, 2022 here I come...

[bitseeker]

Happy New Year, or almost new year, to everyone (depending on location)!

Hope you're doing well, or as well as can be under the circumstances. It's been a rough year. Lost some friends and family, and work has been too busy, but I hope 2022 will be better.

What are your goals, TEA or otherwise, for 2022? Mine are to acquire less TE, shrink my repair queue, and spend more time in the forum.

(And catch more typos before submitting a post.)

[tautech]

Vince
A useful Coax chart I posted is in this thread:
https://www.eevblog.com/forum/testgear/quality-test-cable-rg58-alternative/

BTW, forget about using the thin flexible probe cables, they are not 50 Ohm rated and are lossy to help manage reflections.

[tautech]

Happy New Year, or almost new year, to everyone (depending on location)!

Hope you're doing well, or as well as can be under the circumstances. It's been a rough year. Lost some friends and family, and work has been too busy, but I hope 2022 will be better.

What are your goals, TEA or otherwise, for 2022? Mine is to acquire less TE, shrink my repair queue, and spend more time in the forum.

Sounds a fine plan ! 
Already 12 hrs into 2022 in NZ and time for lunch and have a few things on this arvo while the weather is good.

[25 CPS]

Today’s test and audio equipment score.

I originally turned up those Canadian-made Stark resistance and capacitance substitution boxes and discovered that the person selling them also had a Dynaco ST-70 for sale for reasonable money as well, so I bought all three.  An ST-70 has been on my wish list for a long time.  I used to fix and flip them and never kept one for myself because I thought, hey, they're common, and I have a pair of Mk. IVs so I didn't feel the need to hold onto one.  I've been kicking myself ever since so I'm glad I was able to fix that today.

P. S. Note that unruly forum members can be accommodated.

[xrunner]

Happy New Year, or almost new year, to everyone (depending on location)!

Hope you're doing well, or as well as can be under the circumstances. It's been a rough year. Lost some friends and family, and work has been too busy, but I hope 2022 will be better.

What are your goals, TEA or otherwise, for 2022? Mine are to acquire less TE, shrink my repair queue, and spend more time in the forum.

(And catch more typos before submitting a post.)

Happy New Year. Sorry about your losses, but hope you will be in the TEA more often.

I'm currently working on a Boonton Model 42A power meter given to me. It works but needs some TLC and it's missing a button that I'm designing at the moment. I was just now inspecting one of the boards and it looks like green corrosion on the chopper wires, so I'll be redoing those connections now. 

Gald to see you back here!