Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 18799537 times)

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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8850 on: March 24, 2018, 09:23:05 am »
Mutating the thread into something related to cats is a good way to increase posts.

Unfortunately.

+1

... and pets .. and food and life and ... prolly everything else soon.

Basically this is the pub that a bunch of dodgy geezers with a Test Equipment fixation ship up in at the end of the day. Most of the time, between trips to the bar and the pissoir, the conversation will be about TE, but it's only natural that post-pub nosh, "The youth of today...tsk" and mentions of what SWMBO will do when she sees the new boat anchor drift into and out of the conversation from time to time.

Well, yes but...

I suppose I'm suggesting the unwritten rule should be that "anyone not talking about "work" should buy the next round". Such SWMBO conversations are valid "office gossip".
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8851 on: March 24, 2018, 06:26:00 pm »
ploop!

That is all.


mnem
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Offline bitseekerTopic starter

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8852 on: March 24, 2018, 09:07:38 pm »
Nooo. We cannot let the felines take over. Man your stations! :-DD

Agreed that would be a cat-astrophe.

(Sorry I had to do that)

That's OK. It wasn't a-paw-ling.

(But this might've been)
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Offline Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8853 on: March 24, 2018, 11:37:00 pm »
Hooray, it’s my 3000th post. Surely this must be some kind of “least amount of content per post” record?  :palm:
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8854 on: March 25, 2018, 12:02:48 am »
Nope it isn't  :-DD
Who let Murphy in?

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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8855 on: March 25, 2018, 04:48:03 pm »
See my post above for lethal lack of content.  :-DD


mnem
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Online xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8856 on: March 25, 2018, 04:56:56 pm »
*** This post intentionally left blank ***





(Except for the above statement and this notice)
I told my friends I could teach them to be funny, but they all just laughed at me.
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8857 on: March 25, 2018, 05:02:40 pm »
 :palm:
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Online tautech

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8858 on: March 25, 2018, 05:33:52 pm »
We could discuss the cheating Aussies:
https://www.eevblog.com/forum/chat/aussie's-attitudes/msg1461552/#msg1461552

gotta go............
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8859 on: March 25, 2018, 06:13:10 pm »
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Thander-Tek-Extech-Black Star-GW-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8860 on: March 25, 2018, 08:49:53 pm »


meh... it's Cricket. Now if it was Blernsball...


mnem
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Offline GreyWoolfe

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8861 on: March 25, 2018, 09:13:23 pm »
Mayonnaise for the Germans for their Chips  ;)

2.30 pm Mmmm Beer  :popcorn:

SWMBO and I like mayo on chips.  She mixes in ketchup into hers.  She is of German/Italian heritage, I am all Italian American.

17:12  Mmmmm more Beer.
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8862 on: March 25, 2018, 10:40:52 pm »
The German in me likes mayo on chips :)
The German that I am finds it revolting.

Otherwise, not the luckiest of days. After I convinced a co-worker to get a decent used dmm instead of a cheap chink, I pointed him towards a Metrawatt 2036, which he got for around 90.- incl. After that, I decided that I want one too and I get thrown out every time since that.
But I tested my 2 P6562 Tek probes, which arrived last week and which I got for peanuts, and both did show out ok. And I shot myself a nice Burster 10R 0.02% 1.5A Normal resistor/shunt. Always good to have. And an anvil. Of about 250g. The polished upper plane could double as a mirror.
Still undecided on the RCL-issue.
Now I have to take some leave (last year's), but the badly trained monkeys that I have to work with give me second thoughts. When I multiply their damage potention by 10 days, projections become horrible.
 

Offline Terry01

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8863 on: March 25, 2018, 10:47:10 pm »
The German in me likes mayo on chips :)
The German that I am finds it revolting.

Otherwise, not the luckiest of days. After I convinced a co-worker to get a decent used dmm instead of a cheap chink, I pointed him towards a Metrawatt 2036, which he got for around 90.- incl. After that, I decided that I want one too and I get thrown out every time since that.
But I tested my 2 P6562 Tek probes, which arrived last week and which I got for peanuts, and both did show out ok. And I shot myself a nice Burster 10R 0.02% 1.5A Normal resistor/shunt. Always good to have. And an anvil. Of about 250g. The polished upper plane could double as a mirror.
Still undecided on the RCL-issue.
Now I have to take some leave (last year's), but the badly trained monkeys that I have to work with give me second thoughts. When I multiply their damage potention by 10 days, projections become horrible.

LOL....sum ppl! :)
Sparks and Smoke means i'm nearly there!
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8864 on: March 25, 2018, 11:00:56 pm »
Hey ho. Been quiet for a couple of days making test gear. ULTIMATE TEA. Something simple for the weekend. Missing a calibrated signal generator at the moment which is a big problem and to be honest getting annoying now. Mainly because you can't couple a frequency counter to a VFO circuit because it shifts the frequency without massive buffering. This is an issue because my VFO is a black box oscillator (half an SA612AN) so I can't get at it without resorting to friggery or moving the VFO out of the mixer. Function generator isn't stable enough for such tasks. Gah.

1970s solution incoming.

So in the junk boxes I went digging and found some 4MHz crystals, a tube each of 74LS74 and 74LS90 ICs. Scratchy head says if I knock out a square wave from these at say 1MHz, 100KHz and 10KHz I can then get calibration marks at all harmonics (thanks Fourier!).

So little circuit. I didn't bother doing a schematic but basically it starts with a 4MHz colpitts crystal oscillator. The loop capacitance was totally wrong when I picked capacitor values out of my arse to start with so it oscillated on an overtone of about 11.93MHz. Quick frig around with the loop capacitance to get it to roughly the load capacitance of the crystal (30pF) and it's bang on 4MHz. Buffered this with a simple transistor switch with some feedback to keep it stable, then whack it into two stages of D-type flip flop to get it down to 1MHz. This is then let out via a 100pF cap and the rotary switch. Then into a 74LS90 to divide by 5 and then 2 (not 2 then 5 - quiz: why not?). Out via another 100pF cap to 100KHz. Then into the final 74LS00 to err... hmm. Never assume that the IC you want is actually in the tube. This was promptly desoldered and widlarized. Another actual 74LS90 was then soldered in and out via another 100pF cap to get 10KHz. RG174 was used (grounded at one end) to stop crosstalk between the output lines. The switch controls power as well so you select (1) OFF (2) 10KHz (3) 100KHz (4) 1MHz.

Popped it on the counter and poked the trimcap until it was spot on. And it sits there on the 1MHz out at 1.0000000MHz according to my TF930. 1Hz drift either way occasionally. Pretty good!

Ugly but it works. PCB is some FR4 offcut carved, tinned, cleaned. Enclosure was from another unfinished project. I need to find the lid for it. I'll stick a nice label over the big hole in the front one day.



Here's what it sounds like. Note that the harmonics are good to 6m band (50MHz!) from just the 100KHz output. Set to CW with narrowest DSP filter width there. If you look at the S-meter at the top left you can peak it on that rather than the audio.



Right. Bed.
« Last Edit: March 25, 2018, 11:08:09 pm by bd139 »
 
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Online xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8865 on: March 25, 2018, 11:55:19 pm »
Useful little project. I got the same FT-450D here by the way. I just put back up my 6m antenna for the season (a little early perhaps). I want to give FT8 a good workout this summer on 6m.
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8866 on: March 26, 2018, 12:03:49 am »
Well done, got your head down and cracked on with it.  :clap: good to know that the TF930 agreed with the result as well then. :-+
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Thander-Tek-Extech-Black Star-GW-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8867 on: March 26, 2018, 04:08:15 am »
Now THAT is some proper dead-bug architecture right there. 

*INHALES DEEPLY AND CONSPICUOUSLY* Oh yeah... that's some good, skunky shi-i-i-i...  :-DD


mnem
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8868 on: March 26, 2018, 07:08:11 am »
Useful little project. I got the same FT-450D here by the way. I just put back up my 6m antenna for the season (a little early perhaps). I want to give FT8 a good workout this summer on 6m.

Good stuff. Lovely rig for the price. Was quite surprised to be honest.

I’m without a decent antenna at the moment. The garden is a mess and I’m in the process of cleaning it out. Took a whole van load of dead stuff to the tip yesterday. Got a 20/40m loaded dipole in the cupboard ready to go. Until then I’m running a long wire around the living room. I can’t transmit on it as it won’t tune up but it can pulls signals in quite happily. For 30 feet of 7/0.2 wire around the living room I’ve heard contacts as far as Slovakia and the US. Seems to like 20m best. As for 6m, you can pick up FT8 with that wire loop although I need a cable for the rig really. It is less than ideal when I used a voice conference headset on top of the rig :D

Now THAT is some proper dead-bug architecture right there. 

*INHALES DEEPLY AND CONSPICUOUSLY* Oh yeah... that's some good, skunky shi-i-i-i...  :-DD


mnem
*Plops a can of RAID on the table, just in case*

I love raid. My garden looks like a cocaine smuggling aircraft crashed in it at the moment. Mangled metal and piles of white powder everywhere

Well done, got your head down and cracked on with it.  :clap: good to know that the TF930 agreed with the result as well then. :-+

This now raises a further question of absolute vs relative accuracy which can only be resolved with time-nuttery :D
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8869 on: March 26, 2018, 07:14:34 am »
Useful little project. I got the same FT-450D here by the way. I just put back up my 6m antenna for the season (a little early perhaps). I want to give FT8 a good workout this summer on 6m.

Good stuff. Lovely rig for the price. Was quite surprised to be honest.

I’m without a decent antenna at the moment. The garden is a mess and I’m in the process of cleaning it out. Took a whole van load of dead stuff to the tip yesterday. Got a 20/40m loaded dipole in the cupboard ready to go. Until then I’m running a long wire around the living room. I can’t transmit on it as it won’t tune up but it can pulls signals in quite happily. For 30 feet of 7/0.2 wire around the living room I’ve heard contacts as far as Slovakia and the US. Seems to like 20m best. As for 6m, you can pick up FT8 with that wire loop although I need a cable for the rig really. It is less than ideal when I used a voice conference headset on top of the rig :D

Now THAT is some proper dead-bug architecture right there. 

*INHALES DEEPLY AND CONSPICUOUSLY* Oh yeah... that's some good, skunky shi-i-i-i...  :-DD


mnem
*Plops a can of RAID on the table, just in case*

I love raid. My garden looks like a cocaine smuggling aircraft crashed in it at the moment. Mangled metal and piles of white powder everywhere

Well done, got your head down and cracked on with it.  :clap: good to know that the TF930 agreed with the result as well then. :-+

This now raises a further question of absolute vs relative accuracy which can only be resolved with time-nuttery :D
How far down that rabbit hole will you go? What does it ultimately matter if the TF930 is a couple of Hertz out of calibration, surely your project so far is proof enough that's pretty well there? [emoji48]

From mobile device so predictive text might have struck again [emoji83]

Who let Murphy in?

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Offline Brumby

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8870 on: March 26, 2018, 07:34:02 am »
How far down that rabbit hole will you go?

Oh ... that is not a question you want to raise on this thread.......
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8871 on: March 26, 2018, 07:36:51 am »
Hahaha.

This issue is that the fundamental is at 1Mhz so if there’s a merely a 4Hz difference then the 50th harmonic at 50Mhz is actually 200Hz out. The narrow band filter is 250Hz so that gets a little interesting at high frequencies.

Also the load capacitance and crystal tolerance can make a difference or up to about 400Hz in each direction. Also crystal of unknown origin!

Ergo it looks like it works but it all might be wrong :)
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8872 on: March 26, 2018, 11:26:50 am »
My Quickco order finally and ironically arrived which contained a larger enclosure and some more tips.

Slapped the contents of the diddy little DC Quickco controller into the large enclosure with the boost converter.

I took the liberty of installing a "wally diode" so I don't connect it in reverse. My power supply will obligingly chuck 30A through it and watch it catch fire otherwise. I used a rather fat 1N5401. Has a drop of around a volt, handles 3A constant or 200A in tiny peaks and gets warm but not terribly so. Boost converter can make that back up again afterwards so meh.

Objective was to run this off a car battery on the go, comms supply on mains and DC ring offline which it does nicely :)

Heats up in 12 seconds to 370!

Non central positioning of the boost converter was so I could re-use the cable that was already in it ;)





Now to replace the DC jack with some powerpoles. I'll leave that for another day...

Specmaster: the new case came with new panels. PM me if you want them - will drop them in the post to you. Unfortunately they're not quickco branded, despite coming from the quickco store and have a couple extra holes in though.
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8873 on: March 26, 2018, 11:43:01 am »
My Quickco order finally and ironically arrived which contained a larger enclosure and some more tips.

Slapped the contents of the diddy little DC Quickco controller into the large enclosure with the boost converter.

I took the liberty of installing a "wally diode" so I don't connect it in reverse. My power supply will obligingly chuck 30A through it and watch it catch fire otherwise. I used a rather fat 1N5401. Has a drop of around a volt, handles 3A constant or 200A in tiny peaks and gets warm but not terribly so. Boost converter can make that back up again afterwards so meh.

Objective was to run this off a car battery on the go, comms supply on mains and DC ring offline which it does nicely :)

Heats up in 12 seconds to 370!

Non central positioning of the boost converter was so I could re-use the cable that was already in it ;)





Now to replace the DC jack with some powerpoles. I'll leave that for another day...

Specmaster: the new case came with new panels. PM me if you want them - will drop them in the post to you. Unfortunately they're not quickco branded, despite coming from the quickco store and have a couple extra holes in though.

Nice mod with the wally diode  :-+

I thought you was making up a 240v version of this with the 240/24v power module internally?

Thanks for the offer of the end plates, but I managed to find the one that came with mine that got replaced with the smoked plastic one that comes with the Blue controller. It too has extra holes in the front as it was designed to be used with the less expensive controller but these holes are not that noticeable in reality as you can see here.

Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Thander-Tek-Extech-Black Star-GW-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #8874 on: March 26, 2018, 12:05:18 pm »
I've got a mains one as well. I need to finish modding that and I will post it as well. I figured I needed two so I can use one to repair the other one if I need to :D

Your stack is looking pretty good there. The Suhan T12-Q17 panels are the same as the ones I had left over :)
 


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