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Post subject: A little warning on latest production of JJ EL84
Posted: Tue Apr 10, 2012 1:09 pm
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I haven't used a JJ EL84 in quite awhile. But, for those using this tube either from tube sellers or relabeled "Fender Specials" or GT--- a note from one of the sellers:

" Now 3 of the 4 tubes fully tested so far from this batch have failed. One came out of the box with a snow white getter, one flares on power up, and the 3rd arcs over at 300 volts. Even that is not TOO bad (unless the 75% failure rate continues!), but what else is disturbing is that the tubes are all VERY "hot" biasing (based on quick checks, not full test/run in). This is usually a sign of poor screen winding quality with the result being very high bias current.

This in turn means that they are essentially unusable in many pieces of gear, mostly those with cathode-bias or non-adjustable fixed bias.

I'll report back when I have more info - but if you have received JJ EL84s lately (in the last month or two) be VERY careful!! Since they don't have date codes I can't isolate down to a production date. "


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Post subject: Re: A little warning on latest production of JJ EL84
Posted: Wed Apr 11, 2012 7:51 am
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Joined: Tue Jun 29, 2010 1:20 pm
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Thanks for the heads up BMW2002Ti.

Not sure if this should be based on only one quad though. Example, the one that was white was from the glass being cracked, and could have happened in shipping.

In this case, the GT S-version are not relabeled JJs, but are made specifically for GT in the JJ factory.

I have a set of GT-EL84-S in my BJr, they have been great for some time now. There is no JJ label, and upon close inspection, the differences between the JJ and GT are apparent.

It's bad enough that the misinformed are using terms like "JJ/Tesla" (no such thing), but now they want to start mislabeling GTs as relabeled JJs. :roll:

I may have to start referring to my "RCA Sovteks", as RCA has the same relationship with Sovtek that Tesla had with JJ. In other words, Sovtek used some old RCA equipment (maybe even "borrowed" a patent or two), just like JJ bought some old Tesla equipment, nothing more. There was never an overlap between Tesla and JJ, and the JJ tubes were not the same tube that Tesla made.

:oops: Sorry for the mini-rant. :lol:

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