Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

Kosmic, my main scope is a MSOX3014T, and I hope it will last for the next 5 years at least.

Nice scope! 5Gs/s is pretty cool 

MSOX3104T sorry typo

This is a very nice scope, too. 110GHz bandwidth. Realtime.



Source:
https://twitter.com/thesignalpath/status/1042082921585274884

Edit:
Review of the scope:
http://thesignalpath.com/blogs/2018/09/18/keysight-keysight-uxr-110ghz-bw-256gs-s-10-bit-4-channel-real-time-oscilloscope-teardown-experiments/

Post #1000, too

[Brumby]

Now that's the cat's meow!

[bd139]

I wouldn't let a cat near that. Or in my house 

[BU508A]

I wouldn't let a cat near that. Or in my house 

Two or four legs? 

[mansaxel]

On the bench getting its cable fixed is the PERFECT mic for Discord:

But does it get a PTT button?

currently researching silent mute/unmute button circuits for integrating in mic preamps

[med6753]

Kosmic, my main scope is a MSOX3014T, and I hope it will last for the next 5 years at least.

Nice scope! 5Gs/s is pretty cool 

MSOX3104T sorry typo

This is a very nice scope, too. 110GHz bandwidth. Realtime.

Where's the tubes? Gotta have vacuum tubes. No tubes....no thanks. 

Damn, that's nice! 

[BU508A]

Where's the tubes? Gotta have vacuum tubes. No tubes....no thanks. 

Damn, that's nice! 

If you want tubes, then you should have to go after some TWT (travelling wave tubes). 
There are some which are going up to 110GHz with an output of 3.7W! 

https://books.google.ch/books?id=bvAnDwAAQBAJ&lpg=PA463&ots=cGiVlKQzPv&dq=TWT%20110GHz&hl=de&pg=PA463#v=onepage&q=TWT%20110GHz&f=false

[Kosmic]

Kosmic, what brand probe adapter did you use?  And congrats on one thousand!   

The probe to bnc adapter is a Lecroy PP005-BNC (https://www.digikey.com/products/en?keywords=pp005-bnc). Fit most strandard probe tip.

[mnementh]

   On the bench getting its cable fixed is the PERFECT mic for Discord:

But does it get a PTT button? currently researching silent mute/unmute button circuits for integrating in mic preamps

   Built-in, buddy. With LED "Hot Mic" indicator. All the hard work is already done, and it uses the built-in USB Audio driver in Win7-Win10.     But it's a Push-to-KILL button on this one; UP is HOT.

mnem
fuck. I totally need to dust my desk.

[mnementh]

I wouldn't let a cat near that. Or in my house 

Two or four legs? 

2-leggers get the back seat of the Land Rover behind the toolshed. 

mnem
Cleanup? No prob. Garden hose is right THERE. 

[Kosmic]

Cheap nixie tube alert !

https://www.ebay.com/itm/Vintage-General-Radio-1192-B-Nixie-Tube-Frequency-Counter-Powers-On-Nice/233458017081?_mwBanner=1&ul_ref=https%3A%2F%2Frover.ebay.com%2Frover%2F0%2Fe11021.m43.l1120%2F7%3Feuid%3D3aebd2910f5d456b8127759f70b705d8%26bu%3D43194197782%26ut%3DRU%26loc%3Dhttps%253A%252F%252Fwww.ebay.com%252Fulk%252Fitm%252F233458017081%26sojTags%3Dbu%3Dbu%2Cut%3Dut%26srcrot%3De11021.m43.l1120%26rvr_id%3D0%26rvr_ts%3D80595fe316f0aaa7341111abffff2301&ul_noapp=true&pageci=5b5c392d-03fc-4db5-837e-22b59e59821f

[mnementh]

But does it get a PTT button? currently researching silent mute/unmute button circuits for integrating in mic preamps

   Built-in, buddy. With LED "Hot Mic" indicator. All the hard work is already done, and it uses the built-in USB Audio driver in Win7-Win10. 

A little followup: Testing with the Discord loopback feature reveals a noticeable pop on engaging the mic; however, it appears to be mechanical noise as I can make it pretty much disappear entirely by careful operation of the PTK button. I may look into testing with a remote pedal here shortly, if I can find a compatible jack to wire in.

mnem
*back into parts-hunting hell*

[mnementh]

Well fuck. Wifey just killed my current tinkery project; a sheet music holder with built-in LED lighting to go on the keyboard I recently refurb-ed for her. She says it would just get in the way with her online lessons. 

Now trying to find something to do, other than F5-ing my auctions ad-nauseum...

mnem
 

[Specmaster]

I guess the cold weather is making her less of an enabler for you now then 

[BU508A]

Cheap nixie tube alert !

https://www.ebay.com/itm/Vintage-General-Radio-1192-B-Nixie-Tube-Frequency-Counter-Powers-On-Nice/233458017081

Thanks for the reminder. 
I have bought end of November the very same model too for around 50 Euros.
Will do some pictures this evening and a little teardown. 

[med6753]

More work on the 535A specifically on the CA plug-in and get it stable.

After an extensive amount of  fiddle farting and careful tweaking finally got both channels relatively stable. Channel A trace was completely off screen and Channel B went off screen when flipping from + polarity to – polarity. The fix for both was EXTREMELY sensitive DC balance control. The least amount of noise on the pot plus the fact that it's sealed and can't get deoxit in there is enough to pull your hair out.  But here's both looking good.....finally.

Many of the tubes in this plug-in are hand selected for certain characteristics and have unique Tek P/N's on them. So for example you can't just grab a 6AU6 off the shelf and plug it into a slot that's calling for a 6AU6. So it would behoove me to have some sort of spare on hand. I found this CA plug-in on flea bay that appears to be in decent shape and a reasonable price. It's been ordered.

Next on the agenda is to find out why the Amplitude Calibrator went tits up.       Edit....Fixed, just needed a spray of deoxit on the switch.

[kj7e]

Happy to report the seller outback6 on ebay is legit.  Received my new to me HP 8920A which I think I damn near stole and its in great shape, fully functional, with the options listed.  It was well packed and arrived safe.   Only had a hour to play with it last night (almost brought it into work with me today).

The seller has another one listed starting at $600, but only has the OCXO option, no spectrum analyzer.
https://www.ebay.com/itm/C164770-HP-8920A-RF-Communications-Test-Set-Option-001-RF-Gen-Anl-AF-Anl-Osc/333469043207

Same seller has a HP 53310A MDA for sale cheep too.

Ill post up some tests results and maybe even some teardown photos later in the week.

[med6753]

Now that the Amplitude Calibrator is working what's left to do is install the covers and do a burn-in. Damn the electric bill!   

Yes, when the time delay relay clicks to apply full B+ to the scope the lights on the bench flicker. 

What I find amazing, and I may jinx myself for saying this, is that so far I have NOT had to replace any parts. I swear these old Tek's could survive a well placed nuke. 

And just as a side comment. The contents of this thread for the past week or so have been absolutely stellar. The diversity of TEA interests from boat anchors to 110GHz scopes. And from dragons (mnem) to pyromaniacs (bd139).   Isn't it nice when we stay away from politics/bitching/bellyaching and concentrate on our hobby and flip the bird to shit around us? Although maintain a sense awareness but keep it out of here.   

[mnementh]

I guess the cold weather is making her less of an enabler for you now then 

I'm experimenting on my microphone for Discord right now; trying to isolate the pop noise and see what I can do to make it go away without totally destroying the thing. So far it's being pretty fucking annoying; DPDT switch with power for LEDs on one half and other half shunting the mic input to GND when off.  Testing with another mic that has long enough cable to isolate the PCB mechanically right now. 

Still have not dusted my desktop. 

mnem
*tinker-ily*

[AVGresponding]

Cheap nixie tube alert !

https://www.ebay.com/itm/Vintage-General-Radio-1192-B-Nixie-Tube-Frequency-Counter-Powers-On-Nice/233458017081?_mwBanner=1&ul_ref=https%3A%2F%2Frover.ebay.com%2Frover%2F0%2Fe11021.m43.l1120%2F7%3Feuid%3D3aebd2910f5d456b8127759f70b705d8%26bu%3D43194197782%26ut%3DRU%26loc%3Dhttps%253A%252F%252Fwww.ebay.com%252Fulk%252Fitm%252F233458017081%26sojTags%3Dbu%3Dbu%2Cut%3Dut%26srcrot%3De11021.m43.l1120%26rvr_id%3D0%26rvr_ts%3D80595fe316f0aaa7341111abffff2301&ul_noapp=true&pageci=5b5c392d-03fc-4db5-837e-22b59e59821f

Very nice, and I'd be tempted if it weren't for the concern that by the time it reached the UK, the valves would be in the form of a 10 thousand piece jigsaw puzzle...

[mansaxel]

But it's a Push-to-KILL button on this one; UP is HOT.

I've lost count on the times I, in haste, resoldered my Yamaha footswitch used to control outboard audio gear like reverbs and delays because some device wanted NO, other devices wanted NC.  (Probably should take the little ON-ON DPDT switch I speculatively bought at Elfa today and wire it for selection of NO vs NC. in the footswitch. Especially if it fails to fit in the mixer I perhaps bought it for. )

Thus, I wonder whether it was possible to revert the action of said PTK to a PTT.

[mnementh]

I LIKE it being PTK... 

mnem
Priorities, man!!!

[med6753]

Still have not dusted my desktop. 

mnem
*tinker-ily*

Get to it. These work. 

[mnementh]

Still have not dusted my desktop. 

mnem
*tinker-ily*

Get to it. These work.     

I can't hear you over how awesome I sound (in the reverb of the Discord loopback test mode)... 

mnem
damn that barely audible 60hz hum with this other microphone...

[Martin.M]

med if you need white graticules instaed of the red turn the plexy headstanding.