EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: TheNewLab on July 05, 2018, 02:12:27 am
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Cannnot think of a better subject. I Just bought two. (accidentally), found them on eBay for under $200. They are averaging around$300 now.
My Experience so far with this AWG
I have soooo tried to avoid these "big old tanks" My habit is to open them up because I read and learned abut how getting something used, and the person's experience was a bunch of cockroaches came out. I have had spiders and dead bug colonies. About opening it up. It is finicky because of the braided wire around each end of the cover. It was a real b..to get it back together. It had been calibrated that expired in Sept 2017 from a reputable firm that does that stuff.
It uses a 3.5 inch floppy disk to create your own custom waveforms. I still had some. There are floppy disk to USB adapters that can be found.
Being so old, I just went ahead and attached the drive right to the side of the unit
Why an AWG old and a tank?
1.) I was looking for something that I could check a quality of a 200MHz scope.
2.) looking at Rigol/Hantek/ etc could only find similar pricing for 40 to 60MHz AWG, for over 100MHz I was seeing over $1,000 USD and higher up to $2,00 USD, even used...
3.) I dreaded getting something so big and heavy, and a CRT era. but I downloaded the manual measured and re-created the weight.. At this point I said maybe.
4.) At the Tektronics site, I learned that it had been i production back as far as 1994, but they were still selling them right up to 2006. Not so bad. perhaps the clincher was they still had the most recent firmware updates down loadable, and the price.
a 250MHz, Tektronix relatively recent for under $300 shipped to my door? fine..I had to completely redo the teest gear shelves to accommodate the beast!
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These units may also be subject to Tektronix' early nineties capacitor plague. Look very careful for leaking SMT electrolytics. If they leak, you have to replace all of them!
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Doesn't that model run at 250 MS/s? With two points per waveform, the maximum output frequency would be half that or 125 MHz. Is there an option that increases the max output to 250 MHz?
Even 125 MHz is a good deal for under $200.
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I'm in the business for an arb myself, and at the moment my top contenders are the Siglent SDG2042X and the Lecroy Arbstudio, although the Arbstudio would have to be used (can't afford a new one).
I did see these old Tektronix generators which all look like old Tektronix scopes on ebay.
Looking at the specs of this AWG2021, I really can't see what's supposedly so great about it. The sample rate is only 250MS/s, only 12 bit vertical resolution, and the memory is just 256k. And it only has a single 50 ohm channel, and draws around 300W. :scared:
If I compare this with the Siglent SDG2042X (2 channels @ 50 ohms/1M switchable, 1.2GS/s, 16 bit resolution and 4M of memory, and consumes less than 50W) which it appears can also be hacked to 120MHz then this Tek AWG2021 doesn't look very impressive. I would even say it looks really poor.
The arbs I've looked at have all at least 14 bits of vertical resolution, and from what I understand a higher resolution and higher sample rate means a cleaner signal.
Even Siglent's old arbs like the SDG1020 had 14 bit resolution, and Rigol's arbs do as well. And I checked, the super cheap Feeltech FY6600 is 14 bit as well!
I don't think this AWG2021 is any good to check scope quality @ 200MHz.
Why would I go for an old tank with inferior specs and no warranty which sucks power like there's no tomorrow and which forces me to fiddle with obsolete storage media?
Or am I missing something? :-//
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Maybe a generator like the Siglent SDG2042X was outside the OP's budget? I dunno. It sounded like he wanted to get something that could output more than 200 MHz, which it doesn't seem like the AWG2021 can, but didn't state a budget.