Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

How about the other way around?   

Only if she's wearing.   And no panties and a redhead

If she's wearing both, run like Hell. She's obviously a serial nerd-sniper. 

mnem

[xrunner]

LOL! 

That scene is for the wives of hams. She's saying see - here's what I do while my husband is on the radio. Get yourself a beer and enjoy yourself!

But the rest of his house is neat because he managed to keep a wife who takes care of it but obviously never ventures into his shack.     

This old picture came into my head 

[bd139]

But the rest of his house is neat because he managed to keep a wife who takes care of it but obviously never ventures into his shack.     

This old picture came into my head 

The good old days when women knew their place. 

Why is there suddenly a mob outside my place with tar and feathers? 

Actually this seems to be the era a lot of hams live in.

My father was of that generation I think 

[mnementh]

On the occasion of 1554 thanked posts:      Who gets the connection?

https://www.mouser.com/c/connectors/circular-connectors/circular-mil-spec-connectors/?q=1554

mnem
I think this connection might be more fun:   

https://www.pnj.com/story/entertainment/events/gopensacola/eats/2014/08/19/beer-garden-black-lager/14296115/

[mnementh]

Free entertainment!  https://www.eevblog.com/forum/dodgy-technology/the-non-linear-plasma-reactor/     

I didn't even need to read it. The posting style says crazy. I am watching Simon avidly 

Duly noted and inappropriate comments left. 

mnem
"Very helpful... very helpful indeed." Chibila thought to himself...

[tggzzz]

ebay and their silly algorithms... "You searched for transistors recently, here's some helpful links to similar products" followed by a list of random auctions for every type of transistor you could think of... 

ebay obviously doen't understand that people don't search for ANY transistor, but a particular part No. Even worse, the search was for a 7912CV linear regulator, NOT a transistor.

That was a remarkably good algorithmic result

If you want to see "bad", have a look at what i-bidder/bidspotter or the-saleroom serve up. "Irrelevant" doesn't even begin to do their suggestions justice. Only £30k-35k needed for one suggestion.

[mnementh]

Of course there are. A bit of Pallet wrap, repurpose some raised floors with refrigerated airflow and butthead Bob's your frosty uncle. 

What people who propose these things usually don't realise is the way people decompose. This happens, albeit at lower rate, also when chilled. Turning the humidifier off in the HVAC plant will of course stall and reform the decomposition somewhat, but usually not enough to create a large difference.

We usually end up as soggy messes, if we're not actively dried-out. Pallet wrap is but a stop-gap measure.

Freezing would of course pause the process, but I know of no computer room cooler in existence that would actually manage to freeze something, except itself where inconvenient; i.e. "icing up".  There is, you see, one set of people more optimistic than agile project managers, namely HVAC designers. There is no so constantly underdelivering field  of modern engineering. Too little, too warm, in the wrong spot, and leaking (mighta been condensate from piping not insulated well enough, though). That about sums it up.

I think you missed my point... to completely repurpose said chill air delivery for keeping Butthead Bob frosty. That said... yes, I know it's silly. That was kinda the whole point.

mnem
*currently seeking a grant to further develop my funny walk*

[AVGresponding]

How about the other way around?   

Only if she's wearing.   And no panties and a redhead

If she's wearing both, run like Hell. She's obviously a serial nerd-sniper. 

mnem

0.666 recurring (we need diacritical combinations allowed here...), appropriately enough.

[mnementh]

I'm looking for a two wire AC power cord for my vintage test equipment. Maybe anyone here can recognize it? 

I have a KIAG/Kistler 5001 Charge Amplifier on my desk with an unusual power plug. It's a rectangle shape with two pins and no PE. The ratings say it's meant to be powered at 220 V/110 V, 5.5 W

The needed power receptacle was probably used during 1950's or 1960's and it seems like it's a Swiss type (Kistler is a company with origin in Switzerland). I've found a picture of the original cable but the markings on it are too small to be read. I've included a drawing with the geometry of the plug.

I've checked eBay for vintage power cords (e. g. for vintage electrical appliances) but most pictured similar types don't fit. I even checked the (digital) museum of Plugs and Sockets, no luck...
https://www.plugsocketmuseum.nl/ApplConn_overview.html

Any idea or hints?   

It does look very similar to the 2 wire detachable cords typically used on old portable deep fryers and I think on stationary mixers too.

Yup. These radio or mixer connectors are IEC C8. Just held my calipers to one of them and it is 2.85mm pin socket at the rubber end, metal inside could be 3mm, and 8mm pin distance. Worth a try as they are dirt cheap.

Be careful... IIRC, those C7 cords (polarized or non-polarized) are 8.6mm spacing and made to fit a 2.2mm pin. Pressing hard enough to force it on there is very likely to break the socket, or break the PCB it is soldered to if not supported properly by the chassis.

mnem
 

[vk6zgo]

I actually thought about getting an amateur radio licence at one time too.  It was a ride in a friend's car that started changing my mind.  The friend has a bunch of scanners going all the time and a bunch of ham radio operators did this check in thing.  I asked what this was and the friend explained that they routinely do this.  I couldn't stop laughing because it sounded like they were taking attendance at school.

Hams are required by the regulations to state their callsigns at intervals of (usually) 10 minutes or less.
What you heard was probably a "Net", on 2m FM.

These, are often, effectively, "club meetings", so people 'log in' for the club records, but even informal Nets often like each station to check in, as a "round table" conference becomes seriously unwieldy if you can't remember who is next, so it is normally the function of the control station to "call the roll."

In passing, hams would think someone with a bunch of scanners in their car to be a bit "geeky".

On another occasion, one ham operator was moaning about how everyone was complaining that they had a hard time hearing him.  His audio was clean but very quiet.  My first thought was that he was undermodulated from the way it sounded.  The other guys he was talking with kept saying he was very quiet.  I kept saying to my friend that it sounds undermodulated, what does the index of modulation look like and the other ham operators kept saying, dunno, sounds quiet, don't know why and left this guy swinging in the breeze.  Nobody recommended checking out the audio chain and making sure everything was set up so his normal speaking voice would bring his transmitter up to 90% or so modulation or took a look with a spectrum analyzer to see what his RF output looked like.  TinySA aren't expensive.  None of the people this guy was speaking with could or would offer any troubleshooting tips to help get him started chasing down why his audio was so low.  The unhelpful indifference was striking.

The "audio chain" in many ham radio transceivers is probably a couple of transistors,either discrete, or part of an IC, so it would all come back to maybe a faulty, or incorrect mic, or maybe a coupling capacitor.

Again, if you were hearing him on a scanner, he was quite likely to be on 2m FM, so it would be deviation you would be looking at.

Some people can get a pretty good idea of deviation of a speech modulated signal from looking at a spectrum analyser  but the usual method is replace the mic with an audio generator, either for a better estimate, or to look for Bessel "zeros".
A deviation meter is normally used for simple FM signals in industry.

Hams may well not have the equipment to measure deviation, & perforce, must take the manufacturer's settings as being correct, & assume any drop in deviation to be due to an audio fault.

Another possibility is that his radio is set to a lower deviation standard than the others in the group.
There are several of these, & equipment still in commercial service or recently repurposed is usually set to the lower deviations.

There were a few other things that shifted my view on amateur radio but the hamfests finished the idea off for me.

As for showers, the utility bills have these styleized meter gauge graphs and the one for water consumption is consistently in the yellow.  There's no such thing as a short shower for me.  And clean clothes.  Definitely.  And I prefer coveralls to overalls.

[vk6zgo]

How did we ever get on the subject of decomposition of human tissue?  I think we missed some subjects in getting here. 

What's next? Mortician training? 

And people on this thread criticise hams for talking about weird stuff!

[mnementh]

Today’s WTF courtesy of instagram:   

So what... the fact of a Nano embedded in a hobbyist-level project?

Or the fact of using Turps instead of IPA (mild cringe)?

Or the fact of getting that filter module wet (I dunno if it's hermetically sealed or not)?

Guy's a professor teaching fundamentals of electronics in Brazil:

https://linktr.ee/allelectronics

https://cursoseletronica.com.br/

https://www.youtube.com/allelectronicschannel

mnem
 

[bd139]

Today’s WTF courtesy of instagram:   

So what... the fact of a Nano embedded in a hobbyist-level project?

Or the fact of using Turps instead of IPA (mild cringe)?

Or the fact of getting that filter module wet (I dunno if it's hermetically sealed or not)?

Guy's a professor teaching fundamentals of electronics in Brazil:

https://linktr.ee/allelectronics

https://cursoseletronica.com.br/

https://www.youtube.com/allelectronicschannel

mnem
 

It's the turps. Most of the turps out there isn't turps. Proper turps is not residue free by a mile. Crap turps is even worse and probably compromised a chunk of what's on that board.

[DH7DN]

I'm looking for a two wire AC power cord for my vintage test equipment. Maybe anyone here can recognize it? 

I have a KIAG/Kistler 5001 Charge Amplifier on my desk with an unusual power plug. It's a rectangle shape with two pins and no PE. The ratings say it's meant to be powered at 220 V/110 V, 5.5 W

The needed power receptacle was probably used during 1950's or 1960's and it seems like it's a Swiss type (Kistler is a company with origin in Switzerland). I've found a picture of the original cable but the markings on it are too small to be read. I've included a drawing with the geometry of the plug.

I've checked eBay for vintage power cords (e. g. for vintage electrical appliances) but most pictured similar types don't fit. I even checked the (digital) museum of Plugs and Sockets, no luck...
https://www.plugsocketmuseum.nl/ApplConn_overview.html

Any idea or hints?   

It does look very similar to the 2 wire detachable cords typically used on old portable deep fryers and I think on stationary mixers too.

Yup. These radio or mixer connectors are IEC C8. Just held my calipers to one of them and it is 2.85mm pin socket at the rubber end, metal inside could be 3mm, and 8mm pin distance. Worth a try as they are dirt cheap.

Be careful... IIRC, those C7 cords (polarized or non-polarized) are 8.6mm spacing and made to fit a 2.2mm pin. Pressing hard enough to force it on there is very likely to break the socket, or break the PCB it is soldered to if not supported properly by the chassis.

mnem
 

Thanks dwagon!  I won't force it! Those plastic parts are delicate and break easily    I'll use a proper buttplug conical shaped tool in order to widen that tight hole socket! 

Hehe, adult jokes aside - I'm thinking of 3D printing a receptacle with proper strain relief and 3 mm sockets.   

[mnementh]

Thanks @med6753 @Peter_O and @Rob

I tried the IEC C8 / IEC 60320 "figure-8" socket and the pins do fit into the rubber. I wasn't able to push the 3 mm pins into 2.85 mm sockets as they are slightly oversized. It was possible to establish electrical contact but it's not very safe from the electrical safety point of view. The pins have contact on the tips and the connection isn't very reliable, nevertheless I was able to power the unit on for a short time. 

 

I was afraid of this. My suggestion:

Get a 1/8" (3.17mm) drill bit. Round the shank end a bit against a Grinder, belt sander, etc, so that the end is smooth & rounded; just enough to get rid of the sharp edge.

Clamp this drill bit in a vise with shank end sticking out.

Soften the C7 end of your cord a wee bit with hot air. Just a bit to make it malleable, not enuf to make it really soft.

Force the C7 end of the cord onto the drill bit with a twisting motion until you've "resized it". Repeat for other pin socket.

The pin sockets in the cord are supposed to be a wee bit "springy"; using a 1/8" drill should make it just about right after it returns to a "resting state".

mnem
 

[xrunner]

I actually thought about getting an amateur radio licence at one time too.  It was a ride in a friend's car that started changing my mind.  The friend has a bunch of scanners going all the time and a bunch of ham radio operators did this check in thing.  I asked what this was and the friend explained that they routinely do this.  I couldn't stop laughing because it sounded like they were taking attendance at school.

The "audio chain" in many ham radio transceivers is probably a couple of transistors,either discrete, or part of an IC, so it would all come back to maybe a faulty, or incorrect mic, or maybe a coupling capacitor.

Again, if you were hearing him on a scanner, he was quite likely to be on 2m FM, so it would be deviation you would be looking at.

Some people can get a pretty good idea of deviation of a speech modulated signal from looking at a spectrum analyser  but the usual method is replace the mic with an audio generator, either for a better estimate, or to look for Bessel "zeros".
A deviation meter is normally used for simple FM signals in industry.

Hams may well not have the equipment to measure deviation, & perforce, must take the manufacturer's settings as being correct, & assume any drop in deviation to be due to an audio fault.

Another possibility is that his radio is set to a lower deviation standard than the others in the group.
There are several of these, & equipment still in commercial service or recently repurposed is usually set to the lower deviations.

Almost all the hams I know will not go into a radio and check anything. I only know of two that will. One lives in a close-by city and sells items he gets from hamfests all over the US, and so has to fix radios. The other one will go in and check things since I've been prodding him to learn and do more with test equipment. I know of no other ham that would have the equipment to check deviation or even know how to. Hell, can they even explain FM deviation?

The most they have are cheap SWR/PWR meters of dubious accuracy in most cases, and a DMM. All they can tell people what to do, for example if your audio was low, is go into menus and muck with settings, speak louder, or send it back to the manufacturer. They will not get schematics and even attempt to understand anything at all about the radios circuits.

Maybe 10 or 20 years ago radios would be checked out by hams and aligned, but those days are almost gone. Most of the alignment is from a service menu and while that's easier in a sense, it still requires a setup of measurement equipment which they either don't have or will not bother with. There is hardly anything inside that can even be tweaked like coils and trimmers any more (think SDR technology).

I know I'm ragging on them as a group, and I don't want to make any sweeping generalizations. That is why I will say again in my local group most hams will not do these things, I can't speak for any other groups of hams out there. However, I know my group very, very well ... 

[DH7DN]

Thanks @med6753 @Peter_O and @Rob

I tried the IEC C8 / IEC 60320 "figure-8" socket and the pins do fit into the rubber. I wasn't able to push the 3 mm pins into 2.85 mm sockets as they are slightly oversized. It was possible to establish electrical contact but it's not very safe from the electrical safety point of view. The pins have contact on the tips and the connection isn't very reliable, nevertheless I was able to power the unit on for a short time. 

 

I was afraid of this. My suggestion:

Get a 1/8" (3.17mm) drill bit. Round the shank end a bit against a Grinder, belt sander, etc, so that the end is smooth & rounded; just enough to get rid of the sharp edge.

Clamp this drill bit in a vise with shank end sticking out.

Soften the C7 end of your cord a wee bit with hot air. Just a bit to make it malleable, not enuf to make it really soft.

Force the C7 end of the cord onto the drill bit with a twisting motion until you've "resized it". Repeat for other pin socket.

The pin sockets in the cord are supposed to be a wee bit "springy"; using a 1/8" drill should make it just about right after it returns to a "resting state".

mnem
 

I was thinking about playing with drill bits. Yeah, I'll try as you suggest! Thanks alot! 

[vk6zgo]

Today’s WTF courtesy of instagram:   

So what... the fact of a Nano embedded in a hobbyist-level project?

Or the fact of using Turps instead of IPA (mild cringe)?

Or the fact of getting that filter module wet (I dunno if it's hermetically sealed or not)?

Guy's a professor teaching fundamentals of electronics in Brazil:

https://linktr.ee/allelectronics

https://cursoseletronica.com.br/

https://www.youtube.com/allelectronicschannel

mnem
 

I recently ordered two bottles of Methylated Spirit (denatured alcohol) from Coles, a large Oz grocery chain which has, as of the last few years, got into online sales/home delivery in a big way.
Someone there thought an appropriate substitute would be "Mineral Turps".
I now have more of the latter than I am likely to use any time soon!

[25 CPS]

RE: Ham Radio. Many, many years ago I considered getting my ticket but at that time CW was still a requirement for all classes of operators and I was put off by it. Actually, I was too lazy to try to learn it.

Sour grapes...

I actually thought about getting an amateur radio licence at one time too.  It was a ride in a friend's car that started changing my mind.  The friend has a bunch of scanners going all the time and a bunch of ham radio operators did this check in thing.  I asked what this was and the friend explained that they routinely do this.  I couldn't stop laughing because it sounded like they were taking attendance at school.

If all you know of ham radio is fleamarkets (hence the name) and vhf repeaters you actually don't know much of it.

Then again, we already have our share of frustrated old geezers around so we don't need any more on the air. Thanks for deciding to stay away.

Ralf, DL9KCG
...no longer active as a radio amateur because of too much interference from processors and SMPS but who still has a shower and changes his underwear every day.

Sour grapes? Perhaps. But sounds like you mad and I guess I can't blame you. To look at Ham Radio today the smart and intelligent ones are quickly becoming SK's and what you have left are "appliance operators" who haven't got a clue other than key down and talk BS. Nothing more than an extension of the 11 meter Crap Band.

He's mad.

Actually, I've seen that kind of anger before.  Instead of respecting the "based on what I've seen and experienced, I've decided this is not for me" decision, he's gotten very angry.

I've written before about volunteering at several railway museums.  There's one I used to be a member of and tried to help out with but walked away from after some really crummy experiences that my best friend and I had.  The amount of snarling, furious geezers taking issue with the idea that free labour and free money was walking out the door after being crapped on was unreal.  The truly insane part was several of them actually got in touch with me privately after and told me I should suck it up, pay my membership fee, continue donating money and work and put up with their garbage just because that's what they expected of me.  Respecting the decision that I didn't want to do it anymore wasn't on the table.  I volunteer at some places and not others.  Mainly it comes down to I have limited free time outside of work, limited disposable income, and multiple hobbies that I try to shoehorn in.   Some places respect that, others don't, and the ones that don't typically blast people like what we saw there.

With respect to "look at Ham Radio today the smart and intelligent ones are quickly becoming SK's", there was some overlap in attendance at a couple of the hamfests I went to and I ended up purchasing some beautiful old boat anchors from an elderly gentleman on two different occasions.  He was one of the ones who was very quiet, deeply intelligent and knowledgable.  The second time, we were able to sit down and spend some quality time talking and have a really enjoyable afternoon.  Definitely an exception to the rule for most attendees and vendors.  The last time I saw him was in 2019 before the pandemic hit so between COVID-19 and advanced age, I hope he's OK.

I've been wondering for some time if the proliferation of appliance operators in general, not just ham radio, is because the capability of equipment has advanced far enough that the requirement for operator skill and knowledge from back when doing things was hard isn't there anymore, and absent that requirement it's declined across the board over time.

[m k]

I'm looking for a two wire AC power cord for my vintage test equipment. Maybe anyone here can recognize it? 

I can't but nice blog anyway. 

A bit small but sewing machines have all kinds of pedal connectors.

[m k]

On the occasion of 1554 thanked posts: (see image)

Who gets the connection?

1554 thanked posts is the connection of 24/7?

[mnementh]

Today’s WTF courtesy of instagram:   

So what... the fact of a Nano embedded in a hobbyist-level project?

Or the fact of using Turps instead of IPA (mild cringe)?

Or the fact of getting that filter module wet (I dunno if it's hermetically sealed or not)?

Guy's a professor teaching fundamentals of electronics in Brazil:

https://linktr.ee/allelectronics

https://cursoseletronica.com.br/

https://www.youtube.com/allelectronicschannel

mnem
 

It's the turps. Most of the turps out there isn't turps. Proper turps is not residue free by a mile. Crap turps is even worse and probably compromised a chunk of what's on that board.

Yeah... hence my "mild cringe". I can see getting frustrated and looking for another solvent to clean with... but I'd at least follow by a wash in IPA myself.

Tho no idea how much the turps would soak into the cheap paxolin PCB; as you suggest, could permanently fuckerize the thing. Since  this thing is RF... I wonder how much turps-soaked Paxolin would affect the velocity factor of the business end of that PCB?

Fuck... I don't even know what the diff in velocity factor is between FR4 and Paxolin... I did Gurrrgle and came up with this:

https://www.pcbway.com/blog/Engineering_Technical/Inroduction_Of_Phenolic_Substrate_And_Epoxy_Substrate.html

...but by the time I got halfway through the first paragraph I was totes so I gave up...

mnem
huhhhh....? where am I...?

[mnementh]

...I recently ordered two bottles of Methylated Spirit (denatured alcohol) from Coles, a large Oz grocery chain which has, as of the last few years, got into online sales/home delivery in a big way. Someone there thought an appropriate substitute would be "Mineral Turps". I now have more of the latter than I am likely to use any time soon!

You need a new project. Something like this:   

mnem
 

[BU508A]

I'm looking for a two wire AC power cord for my vintage test equipment. Maybe anyone here can recognize it? 

I can't but nice blog anyway. 

A bit small but sewing machines have all kinds of pedal connectors.

I looked for Bernina sewing machines (pedal) and found this:


Not exactly what you are looking for, but perhaps an older model will have the plug you are looking for?

[Robert763]

Today’s WTF courtesy of instagram:   

So what... the fact of a Nano embedded in a hobbyist-level project?

Or the fact of using Turps instead of IPA (mild cringe)?

Or the fact of getting that filter module wet (I dunno if it's hermetically sealed or not)?

Guy's a professor teaching fundamentals of electronics in Brazil:

https://linktr.ee/allelectronics

https://cursoseletronica.com.br/

https://www.youtube.com/allelectronicschannel

mnem
 

The module is not a filter, it's a 12V in 9V out isolated DC-DC converter. Almost certainly fully encapsulated. They are inteded for (maybe removed from) Thin Ethernet cards and have at least 1kV isolation. A bit of a sleeper on the parts market, they come in 5V and 12V input versions. Handy for isolated supplies or boosting 12V up (output in series with input) to trickle charge batteries.