Multiple EDC 520s Voltage/Current Calibrators on EBay...

[eas]

I probably would have jumped on one of these a couple of months ago, before I ended up with an EDC 521 and a Valhalla 2701b, but I thought other people might be interested in the listings that appeared today for EDC 520A/LMSC programmable voltage/current calibrators in varying states of dis/repair.

Specs: 100mV, 10v, 100v, 1000v, 10mA and 100mA ranges with 6.5 digit precision in each range. Control via front panel or remote via GPIB.

There is a listing with 5 available for $159/each OBO.
http://www.ebay.com/itm/EDC-Electronic-Development-520A-LMSC-Programmable-IEEE488-DC-Voltage-Calibrator/131652015881

One for $89.99/OBO
http://www.ebay.com/itm/EDC-Electronic-Development-520A-LMSC-Programmable-IEEE488-DC-Calibrator-PARTS-2/131652025966

And another with two available for $69.99 OBO:
http://www.ebay.com/itm/EDC-Electronic-Development-520A-LMSC-Programmable-IEEE488-DC-Calibrator-PARTS-3/151884569914

The last two are listed for parts. The first is listed as used, though the description is the same as the second listing (I suspect in error).

I have no experience with this seller, or this model calibrator. I expect it is quite similar to the EDC 521, which I do have, which is built using a 1n829a zener reference, a precision DAC (precision resistor divider to produce 11 voltage levels, with a value selected for each decade with analog MUX ICs, the value for each decade is then summed) and an output amp. The case is huge, rack width, and 22" deep. It isn't very heavy though.

I haven't done an exhaustive check, but I don't think any of the components are very exotic, though some, like the precision resistors, aren't cheap.

[TheSteve]

Hah, the 69.99 ones might not be the best option - from the description - "Unit powered on momentarily before shutting off and emitting smoke"

[mtdoc]

Hah, the 69.99 ones might not be the best option - from the description - "Unit powered on momentarily before shutting off and emitting smoke"

And it says the same thing in the description of the 5 for $159.   Erroneous cut and paste I suspect....

[nidlaX]

More crusties from svcstore!

[EEVblog]

They don't ship overseas, bummer.

[crispy_tofu]

The $89.99 one's been sold! 

[TiN]

Good that they did not ship overseas, my money safe! 

[nctnico]

They don't ship overseas, bummer.

SVCstore ships overseas; just ask them for a shipping quote. I have bought some equipment from them before. Maybe they don't want to bother with this item so an extra shipping charge may apply.

[eas]

The $89.99 one's been sold! 

Looks like there was a listing I missed. This one is $84.99
http://www.ebay.com/itm/EDC-Electronic-Development-520A-LMSC-Programmable-IEEE488-DC-Calibrator-PARTS-/131652046909

More crusties from svcstore!

That reminds me, I've been meaning to ask, what's the deal with svcstore. They seem to relist the same stuff week after week, but they also get new stuff in, sell a fair amount, and seem to accept a lot of best offers. Anyone done much business with them?

I'm now feeling some temptation to get one of the cheap ones, without the magic smoke...

[nidlaX]

All I know is that I've seen multiple listings where they report the buyer returned an item that was previously working, but is now sold for parts...

Looks like a classic case of seller playing dumb about the condition of their items.

Sent from my LG-E970 using Tapatalk

[feedback.loop]

I picked up one of those listed for $69.99. I offered $40, and they accepted. No shipping since they are not far from my place.
Here is the repair video:
https://youtu.be/pkMySlkpTJk

[Macbeth]

Excellent video  You got a real bargain there.

Perhaps it should go in the repair section?

[feedback.loop]

Excellent video  You got a real bargain there.

Perhaps it should go in the repair section?

Just created a topic in metrology:
https://www.eevblog.com/forum/metrology/edc-520a-repair/
Not sure it is the right place. I hope so.

[feedback.loop]

I see another non-working unit on eBay. There is a photo with the cover off. I see the 1KV optional module installed there.
The board layout is different from the one I repaired. They call it 520D, and it has "D" on the back plate, but still 520A on the front panel.

http://www.ebay.com/itm/EDC-ELECTRONIC-DEVELOPMENT-PROGRAMMABLE-520D-IEE-488-GP-IB-DC-CALIBRATOR-PARTS/361530407694