ECC82 normal vs ECC82 long plate

[felipemuniz]

Have any difference with one to another beyond the plate? Because I bought a ECC82 tube from same seller that, I already bought the same tube a few months ago, and on this time, he shipped a ECC82 with a long black plate.

Well I presume that is ECC82, because seems that the number on tube was erased.

I put the tube on a preamp that I have here, and I measured the cathode and anode voltages, and I got this:

Tube Typical ECC82 This tube
Anode 91.4V 115V
Cathode 2.4V 1.35V

Maybe is just part of the characteristics from the tube, but perhaps the seller shipped a wrong tube.

 

[poynton]

Has he got any more ??


ECC82 12AU7 MULLARD BOX ANODE VALVE TUBE 1PC J | eBay

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[JonSnell Electronic]

The Mullard ECC82 had larger anodes than the 12AU7 type valves. Possibly more current drive maybe but different characteristics to the copies, not that there are any issues with the copies.

 

[DF96]

Tube Typical ECC82 This tube
Anode 91.4V 115V
Cathode 2.4V 1.35V

Maybe is just part of the characteristics from the tube, but perhaps the seller shipped a wrong tube.

Which one is correct? You could do a rough estimate from the circuit and the datasheet.