Test Equipment Anonymous (TEA) group therapy thread

[med6753]

 

[xrunner]

A tribute to bitseeker -

[tggzzz]

I'm retired. I have to keep reminding myself that I don't have to do a freaking thing if I don't want to. 

I'm retired.

I have too many things to do that I don't want to do, but have to do   -- for other people, which is both a positive and a negative.

[tggzzz]

   Oh....and just so my attitude today is clear. I present....   

It would be good to have a 3D model of that, suitable for 3D printing about 1" long. Just the kind of thing to keep in a briefcase/backpack for when it is needed.

[med6753]

A tribute to bitseeker -

(Attachment Link)

(Attachment Link)

Just for giggles I went back and looked....

This thread was started January 15, 2017.

By Page 3, Post 56, dated January 20, 2017 I was here. 

[med6753]

I'm retired. I have to keep reminding myself that I don't have to do a freaking thing if I don't want to. 

I'm retired.

I have too many things to do that I don't want to do, but have to do   -- for other people, which is both a positive and a negative.

I try to keep a low profile which definitely helps. My circle of friends aren't the dependent type. My kids are very independent but Dad is always willing to help out if needed. GF lives 100 miles away and she's very independent anyway. And my Mother is in Colorado which unfortunately puts that burden on my younger brother. But I am going out there in late November for a few days and she's already mentioned some things she wants done around the house.   

[Addicted2AnalogTek]

While using the Tek 284 pulse generator, It has become evident that there's some intermittent contact going on inside of the airline. I was able to get a pulse when tapping on the GR874 pulse output connector, which lead me to believe there was a bad connection somewhere at or near the tunnel diode.  I removed the airline and found the following:

The piece that makes contact with the tunnel diode has bent "fins" on the end that slide over the inner conductor of the GR874 connector. The manual doesn't show a spring in this part, but it seems like the inner conductor of the 874 connector is machined out for one...


I removed the set screw, spring, and ball bearing to clean to ensure good contact with R180.


I also removed the contact and spring on the other side of the tunnel diode and found that the spring has been stretched and twisted.
I also tested the tunnel diode on the 7CT1N, and it's fine.

The springs measure 0.125" OD and are closest to 0.500" length, so those are the ones I've selected. I ordered a pack of music wire type and stainless steel type.

I ordered some new springs from McMaster-Carr.
music wire springs PN: 9657K266
SS springs PN: 1986K45

Time to put this 284 back together so I don't lose anything..

[bd139]

Avoiding buying a spectrum analyser with tracking generator (blasphemy!) because I'm a cheap arse part 1 ... getting a crystal filter sweep.

Managed to persuade the DG1022Z, DG1054Z and my power meter to work together and sweep a crystal filter with it. Hook up is:

(1) DG1022Z out -> 3db attenuator -> xtal filter -> W7ZOI power meter -> DS1054Z channel A
(2) DG1022Z sync -> DS1054Z channel D

Sweep mode on, trigger on channel D, marker on set to measure frequency. Bingo! 



Vertical is 1dB/25mV. Horizontal as I don't care as I'm using the marker output!

Now to solder some caps around it and see if I can get rid of that bloody awful ripple in the middle 

[xrunner]

Avoiding buying a spectrum analyser with tracking generator (blasphemy!) because I'm a cheap arse part 1 ... getting a crystal filter sweep.

Managed to persuade the DG1022Z, DG1054Z and my power meter to work together and sweep a crystal filter with it. Hook up is:

(1) DG1022Z out -> 3db attenuator -> xtal filter -> W7ZOI power meter -> DS1054Z channel A
(2) DG1022Z sync -> DS1054Z channel D

That's pretty neat. Use what you have on hand. 

I guess I'll get me a NanoVNA - might as well. I was waiting to see if the v2 was going to be released that I heard mention of. Some of my ham friends have got the current model but they mostly don't know what all the "colored lines" are, especially the one that goes around and around the Smith chart as they sweep the thing from the lowest freq. it can do to ~900 MHz. I explained it but I'll get one and make some examples to try to "splain it betterer". 

[worsthorse]

Avoiding buying a spectrum analyser with tracking generator (blasphemy!) because I'm a cheap arse part 1 ... getting a crystal filter sweep.

Managed to persuade the DG1022Z, DG1054Z and my power meter to work together and sweep a crystal filter with it. Hook up is:

(1) DG1022Z out -> 3db attenuator -> xtal filter -> W7ZOI power meter -> DS1054Z channel A
(2) DG1022Z sync -> DS1054Z channel D

That's pretty neat. Use what you have on hand. 

I guess I'll get me a NanoVNA - might as well. I was waiting to see if the v2 was going to be released that I heard mention of. Some of my ham friends have got the current model but they mostly don't know what all the "colored lines" are, especially the one that goes around and around the Smith chart as they sweep the thing from the lowest freq. it can do to ~900 MHz. I explained it but I'll get one and make some examples to try to "splain it betterer". 

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

[xrunner]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

[worsthorse]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

smith charts are the bomb.   



and phil smith's book is still the best way to learn about them, though the W0QE simsmith videos are a pretty good place to start...

[daqq]

Damn, I'm looking at a local ad site, they are selling this pretty for 250EUR... must resist, too much...

[bd139]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

Woot proper VNA. S-parameter models are fun. I was measuring S11 and S21 yesterday with my DG1022Z, RLB and the HP 400E. Again a cheap arse I be

Unfortunately only scalar but that's good enough for my needs at the moment. All I need to know is my input match and gain for what I'm building.

[Specmaster]

Also another problem with USB is that USB plugs neatly fit into the ethernet hole too.

Edit: something I hate about new PCs these days. Some Dolby shit gets turned on and makes everything sound like farts in a coffee can until I've found it and neutralised it.

Holy shit balls, I've got 3 days worth of posts to catch up on.......

I think that the Dolby thingy is restricted to laptops, I've noticed a trend in making laptops with Dolby built in to try and add value to them and make them sound better with films in an attempt to make the small tinny speakers give a little bit more performance.

[Cubdriver]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

smith charts are the bomb.   

(Attachment Link)

and phil smith's book is still the best way to learn about them, though the W0QE simsmith videos are a pretty good place to start...

Dammit you just cost me nearly $100!!     You in cahoots with Amazon?!?

 

-Pat

[bd139]

LMAO. Books are evil. There's probably a PDF of it in Library Genesis 

Win. Crystal filter needed different terminating impedances naively frigged with a series capacitor.



That saved me a few quid on a proper off the shelf filter 

I'm getting a hankering for another power supply. I've got three out on this project. Just feels like I may run short soon 

[tautech]

smith charts are the bomb.   

and phil smith's book is still the best way to learn about them, though the W0QE simsmith videos are a pretty good place to start...

Never read much about them other than here and I think watching one of Alan's vids.

Still it doesn't take long to get the hang of them once you get an instrument that can do them.
I like best you can overlay all the important antenna data in a single screenshot:

[Cubdriver]

LMAO. Books are evil. There's probably a PDF of it in Library Genesis 

Probably, but I still prefer books to PDFs and e-readers. 

I'm getting a hankering for another power supply. I've got three out on this project. Just feels like I may run short soon 

https://www.ebay.co.uk/sch/Adjustable-Power-Supplies/181993/i.html?_from=R40&_nkw=HP+Power+supply   

-Pat

[tautech]

Just spotted our resident dwagon seems to be back and busy catching up.

Been on a road trip mnem ?

[worsthorse]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

Gen Hu did a revision of the original NanoVNA, which you can find info on here:

https://github.com/hugen79/NanoVNA-H

As usual with this sort of device, there are a bunch of clones of varying quality, from poor to okay. He sells his version in only two venues, as explained in the github blurb. He's also set up a google drive folder with firmware and some limited documentation.

Since I rarely do anything above 100MHz, the price/performance (at 60USD shipped DHL, including SOL cal fixtues) is pretty darn good.  As a cheap way to learn how to use a VNA, it is even better. 

And, it would be interesting to compare the NanoVNA to the DG8SAQ VNWA 3, too, but I am not that organized.... 

[worsthorse]

smith charts are the bomb.   

and phil smith's book is still the best way to learn about them, though the W0QE simsmith videos are a pretty good place to start...

Never read much about them other than here and I think watching one of Alan's vids.

Still it doesn't take long to get the hang of them once you get an instrument that can do them.
I like best you can overlay all the important antenna data in a single screenshot:

There you go showing off that fancy siglent stuff again... 

[worsthorse]

Dammit you just cost me nearly $100!!     You in cahoots with Amazon?!?

 

-Pat

Yikes! I found my copy, with the mylar charts intact, for $30 (though it took me nearly a year).  A library bookstore that apparently receive a bunch of pristine RF engineering books as a donation...

And yes BD, there are PDF copies out there, including one of the modestly revised edition. If you can't find, I have a copy, PM me.

[worsthorse]

I just got one (the gen hu version) that I haven't had time to take out of the box other than to turn it on and see that it powers up.  Hopefully I will get it on my bench next week. Will look forward to your splaination. 

gen hu version - OK, will look for it.

The explanation? Well, nobody in this thread needs an explanation and I wouldn't insult your intelligence by attempting that LOL.

Most of the hams I know get a "glazed over" look when I ask them if they know what a Smith Chart is for (which is of course is what they see on the screen sometimes with the circles) or what the S11 or S21 numbers mean.

They could just go to You Tube and look at a few short vids and get a pretty good idea, but that, it appears, would be too much trouble. 

Edit: It's a new toy that costs so little they buy it just because everyone else has one. 

Woot proper VNA. S-parameter models are fun. I was measuring S11 and S21 yesterday with my DG1022Z, RLB and the HP 400E. Again a cheap arse I be

Unfortunately only scalar but that's good enough for my needs at the moment. All I need to know is my input match and gain for what I'm building.

Don't you have a vector voltmeter you can jam into the test chain somehow? 

[tautech]

There you go showing off that fancy siglent stuff again... 

I get the new 3.2 GHz VNA/SA combo in a few weeks .................