Test Equipment Anonymous (TEA) group therapy thread

[xrunner]

Here's a comparison of sine wave / square wave capability from a new(ish) Rigol DG1032Z (top) and the 22 year old hp 8904A (bottom). The 8904A can produce sine waves up to 600 kHz and square waves at a max freq. of 50 kHz, so that's what, respectively, the Rigol is set to.

A comparison of sine (600 kHz) and square waves (50 kHz) is attached (Rigol top, 8904A bottom).

It's not a fair challenge regarding square waves - not only is the rise time of the 8904A much slower, it has some jitter which is an artifact of the design - fully explained in the manual on page 3-39, which states the jitter is 600 nS, this value is clearly visible on trace 2. This jitter would be only be associated with ramp, triangle, and square waves, but not on sine waves, which can be generated up to 600 kHz.

If you get one, check out the Agilent waveform catalog below. It has channel setups to produce all kinds of waveforms. I set up a few of their examples:

No. 23 Intermodulation test Signal
No. 62 TTL Level Noise Pulses
No. 64 Trigger Test Signal

(see pics)

8904A Waveform Catalog

[beanflying]

This all started so I could keep my audio stuff maintained and - you know - actually listen to music instead of putter around in the lab.   

You mean actually use the gear you have built or repaired? 

What a concept LOL. 

Actual use of stuff here I was thinking it was just about collecting it and saving it from the worlds dumpsters then repairing, cleaning, polishing and dusting and admiring the stack and deciding where you could fit another bit Test Gear in  .....

[Specmaster]

I too also repair audio gear and use some of as well as selling it on again once repaired. Sod my fist mini hi fi unit last week and now the buyer is returning it claiming it does not work  I had it sitting on my bench for about 12 days in use on a variety of inputs for about 10 to 12 hours a day without a hitch, buyer sets it up and claims no sound from speakers or headphone socket 

When I receive it I'm going to set my video camera up and record the unpacking and connecting it up and test of it. If it works ok for me, I'll send him a copy of the bloody video and see what he has to say about it?

It was well packed as is everything I sell on eBay and it was received in good condition and he claims that there is no evidence of damage to box and I packed it polystyrene angle pieces in the 4 corners of the box so it should be well protected. 

[xrunner]

Actual use of stuff here I was thinking it was just about collecting it and saving it from the worlds dumpsters then repairing, cleaning, polishing and dusting and admiring the stack and deciding where you could fit another bit Test Gear in  .....

Oh I (we) do actually use the TEA we get. It's great test equipment AND saved from the land fill. 

[GregDunn]

This all started so I could keep my audio stuff maintained and - you know - actually listen to music instead of putter around in the lab.   

You mean actually use the gear you have built or repaired? 

What a concept LOL. 

Actual use of stuff here I was thinking it was just about collecting it and saving it from the worlds dumpsters then repairing, cleaning, polishing and dusting and admiring the stack and deciding where you could fit another bit Test Gear in  .....

Well, I admit I have the largest private collection of Dynaco stereo equipment that I know of... having met a few of the people who designed and built their audio hardware I have developed a fondness for the company's efficient and cost-effective design.  They used standard, easy to replace components and overdesigned the electronic part while not wasting money on the knobs and dials.  True, some of their gear looks a bit lowbrow today, but it's easy to keep running within spec and sounds just as good as the modern audiofool amplifiers (sometimes better).  What launched me on the latest path of acquisition was the rebuild of one of their 400 watt amplifiers.  I needed about 6 meters plus a scope to track the behavior of voltages, bias currents, and the like on one channel while bringing it up on a variac.  Made it much easier to see what was misbehaving and to keep it from frying due to some buried device sucking too much current.  Amusingly, the final issue with repairing that amp turned out to be a bad tantalum cap on the input which caused dramatic offset voltages at the output...   

[mnementh]

mnem
"Cookies...? I ate 'em, dumbass. Evil overlord, bent on ruling the galaxy with an iron fist... any of that ring a bell?"

[Specmaster]

Yes, the bastard tants strike again. You can see why bd139 hates them so much on his scopes, it seems that everytime there is a sticky problem,  it's tants that cause them, exterminate them whenever you can.

[bd139]

I love tants. Just not the old ones. New ones are cool. I have hundreds of them and use them in everything

[Specmaster]

I love tants. Just not the old ones. New ones are cool. I have hundreds of them and use them in everything

That's why besides being known as P**** Fingers, you're also the Tant Killer who loves to wilderize them into oblivion on old gear

[bd139]

Indeed. Talking of which I may blow some up this week on camera. iPhone can do 240fps so could be interesting.

[Specmaster]

Haha anything for a bit of pyrotechnics eh, it's the right season. Remember how years ago you could buy Christmas indoor fireworks that you used to set off on a dinner plate?

[bd139]

Yeah I remember them. They were much better when you were drunk. "oh look the black pill is turning into an unhealthy turd" and "it smells like Bhopal in here" 

[Terry01]

I too also repair audio gear and use some of as well as selling it on again once repaired. Sod my fist mini hi fi unit last week and now the buyer is returning it claiming it does not work  I had it sitting on my bench for about 12 days in use on a variety of inputs for about 10 to 12 hours a day without a hitch, buyer sets it up and claims no sound from speakers or headphone socket 

When I receive it I'm going to set my video camera up and record the unpacking and connecting it up and test of it. If it works ok for me, I'll send him a copy of the bloody video and see what he has to say about it?

It was well packed as is everything I sell on eBay and it was received in good condition and he claims that there is no evidence of damage to box and I packed it polystyrene angle pieces in the 4 corners of the box so it should be well protected. 

Recording the unpacking and then the power up is a good idea. I don't know how high end it is but you have to watch out for people nicking bits from things or breaking the item in use then sending them back as broken and expect you to cop the loss.
I had 1 clown do that with an iPhone I sold. They signed for it as received in good order then around 4 days or something later said it was damaged when they received it when it was all well packed etc.
Some people are just chancers. Your right to be cautious.
Hope you get it sorted out ok.

[beanflying]

Mmmm and no I haven't brought it but it does have a certain Utilitarian thing going on and then their is the Nixieness 

[bd139]

I too also repair audio gear and use some of as well as selling it on again once repaired. Sod my fist mini hi fi unit last week and now the buyer is returning it claiming it does not work  I had it sitting on my bench for about 12 days in use on a variety of inputs for about 10 to 12 hours a day without a hitch, buyer sets it up and claims no sound from speakers or headphone socket 

When I receive it I'm going to set my video camera up and record the unpacking and connecting it up and test of it. If it works ok for me, I'll send him a copy of the bloody video and see what he has to say about it?

It was well packed as is everything I sell on eBay and it was received in good condition and he claims that there is no evidence of damage to box and I packed it polystyrene angle pieces in the 4 corners of the box so it should be well protected. 

Recording the unpacking and then the power up is a good idea. I don't know how high end it is but you have to watch out for people nicking bits from things or breaking the item in use then sending them back as broken and expect you to cop the loss.
I had 1 clown do that with an iPhone I sold. They signed for it as received in good order then around 4 days or something later said it was damaged when they received it when it was all well packed etc.
Some people are just chancers. Your right to be cautious.
Hope you get it sorted out ok.

eBay usually side with the buyer on this crap. You can use this to your advantage for punitive treatment of the seller...

One of the guys I was working with earlier this year bought a Thinkpad T450 which was shown as working and booted but just required a disk. When he got it, it had no RAM in it and the seller said that the guy had stolen the stick of RAM in it. So in pure fuck you mode, he RMA'd it via Paypal and send the wanker back an empty box and eBay closed it and refunded it the moment the tracking was marked as delivered 

Mmmm and no I haven't brought it but it does have a certain Utilitarian thing going on and then their is the Nixieness 

It's quite scary to see nixies on the 1980 date code. You can see how far behind the soviets were as literally everything had LEDs by 1980. I don't actually remember seeing a single nixie tube myself until I tripped over an old HP counter in the university labs in the early 1990s.

[tggzzz]

It's quite scary to see nixies on the 1980 date code. You can see how far behind the soviets were as literally everything had LEDs by 1980. I don't actually remember seeing a single nixie tube myself until I tripped over an old HP counter in the university labs in the early 1990s.

Pah. Modern stuff.

Must get myself some dekatrons.

Or build something similar using the neons in my collection (plus resistors and diodes).

[beanflying]

That was an interesting way to spend an hour trawling evilbay.de Brands we don't see much if at all oddballs and even what I reckon was some good buys even a couple of mythical sub $50USD 4W bench multimeters 

For the Tektronix fanboys I haven't seen this one before and not sure if it a rebadge maybe? 175 Euro seemed a little OTT anyway.

[bd139]

Well what a day for incompetent delivery monkeys ruining my TEA fun this week...

Firstly Royal Mail are charging me for my Tektronix 2235 multiplier. But I don't know how much because the stupid muppets didn't deliver the fee card this morning

Secondly Parcel Force sorted my package from RS containing a 10 turn pot to finish a project off to the wrong fucking depot. Hint: I live MILES away from Aldershot:



 

[beanflying]

Ahh Christmas Freight a thing of joy for all 

[tggzzz]

Well what a day for incompetent delivery monkeys ruining my TEA fun this week...

Firstly Royal Mail are charging me for my Tektronix 2235 multiplier. But I don't know how much because the stupid muppets didn't deliver the fee card this morning

Secondly Parcel Force sorted my package from RS containing a 10 turn pot to finish a project off to the wrong fucking depot. Hint: I live MILES away from Aldershot:



 

15 hours ago you wrote https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg2044822/#msg2044822

It is good to see people resolve their own observations 

[bd139]

You were waiting to post that weren't you

[Zucca]

Everytime I jump in the metrology section I feel like I am an idot and I understand only 30-40% of it.
Please tell me I am not alone... 

[tggzzz]

You were waiting to post that weren't you

No, but it was too good an opportunity to pass up.

Sometimes I simply can't resist tweaking people's tails I know I ought to try and break the habit, but nowadays I have to get pleasure wherever I can find it. Can I change my moniker to Victor Meldrew (or Wally)?

[bd139]

Everytime I jump in the metrology section I feel like I am an idot and I undesrtand only 30-40% of it.
Please tell me I am not alone... 

You are not alone.  Perhaps 99% of the time though, that doesn't matter unless you are going to live forever

You were waiting to post that weren't you

No, but it was too good an opportunity to pass up.

Sometimes I simply can't resist tweaking people's tails I know I ought to try and break the habit, but nowadays I have to get pleasure wherever I can find it. Can I change my moniker to Victor Meldrew (or Wally)?

Yes I'll give you your due, the timing was just about perfect

Meldrew for sure

[tggzzz]

I noticed eBay has entirely dried up for Christmas now. There's literally bugger all of interest there that is test gear related. You'd think everyone would be selling it now to try and get some extra cash in for Christmas but nope, dead!

To be less Victor Meldrew-ish and more TEA oriented...

• The 22nd Harwell ARS annual Radio and Electronics Rally takes place on Sunday 10th February 2019, 10:00 until 15:00. https://www.g3pia.net/radio-electronics-rally/
• 14 APRIL 2019 WEST LONDON RADIO & ELECTRONICS SHOW (Kempton Rally) http://www.radiofairs.co.uk/

... plus others listed at https://rsgb.org/main/news/rallies/