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Redfalcon
Posted on Monday, June 02, 2003 - 1:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well I have a choice here between.
6LQ6
6JE6
6ME6
I see they all have differeces in specifications
so which one is actually better and why?
I really don't care about price, but performance and ruggedness are my main concern.

Thank you in advance.
Red Falcon 767 buckeye base...
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Tech808
Posted on Monday, June 02, 2003 - 4:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Redfalcon,

The 6LQ6, 6LF6,6JE6,6JS6c are all pretty much the same.

All require around 50 watts Carrier
and SSB PEP 70watts.

But remember all are NOS (New Old Stock) Tubes any more.

Check out the link below for more information.

http://www.rfparts.com/tubeapp.html

Hope this helps.

Lon
Tech808
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2600
Posted on Wednesday, June 11, 2003 - 10:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well, 6JE6, 6LQ6 and 6MJ6 all have 9 pins. The 6JS6 has twelve pins, but Falcon didn't ask about that one.

For starters, those three numbers appear either alone on a tube, or in pairs or threes. This was called "double-branding", or "triple-branding". This was to indicate that an upgraded tube number would substitute for the earlier versions of the same tube.

"6JE6" is the original type number for this tube design. It got upgraded, and a suffix letter added. The first upgrade was "6JE6A", followed by "B", later on. RCA developed this tube to use in their color televisions, to drive the horizontal sweep "yoke" coil, and also the 5000-Volt Focus voltage and the 24,000-Volt "second anode" voltages to a 17-inch or larger picture tube. It was a stout, reliable performer with one flaw: If the drive to this tube failed, it would cherry up and melt/crack the glass. The shorts that this would cause made lots of other soldered-in parts go "poof" at the same time. All because a little two-dollar driver tube laid down. Bad news for TV repairmen and for RCA. All the other brands had this problem, too. GE TVs used a bimetal thermal switch to sense the heat and shut things down. RCA chose the brute-force approach. They used a "three-legged" circuit breaker that had one leg on the 'sweep' tube. If that tube overloaded, it would trip out. So far, so good, but there's always a time delay on a breaker. Sweep tubes would still get hot enough to crack the glass and fail, even with this breaker in the TV. RCA took their 6JE6 and redesigned it. Made the glass thicker, changed the cap connection from a skinny little wire to a pair of metal straps. Instead of that skinny wire coming through the glass at the top of the tube, they used a "hard seal" cap that had the glass bonded to the outer diameter of the metal 3/8" diameter cap. The metal finish that this process requires makes the cap appear black, not shiny like the original 6JE6.

This rugged construction didn't mean a lot when the TV was running correctly, only when it failed. Around 1969 or so, RCA made the audacious-sounding claim that the new, heavier "6LQ6" would take 200 Watts on the plate for thirty seconds with no permanent damage. RCA figured that their three-legged circuit breaker would kick out in 30 seconds or less.

This way, when that little two-dollar tube died, ONLY the little tube would have to be replaced, NOT the big sweep tube and other stuff.

The specs published in the tube manuals all look about the same, because the all-day continuous ratings aren't much different. That thirty-second rating just isn't in those books.

After the 6LQ6 had been in production a few years, they shuffled the deck. The fat, heavy-duty tube was re-numbered "6MJ6". They had upgraded the original 6JE6 design now to the "C" level. A tube marked "6LQ6/6JE6C" is the skinny version, but later production.

The 'fat' versions made after that change were usually, but not always triple-branded to read "6MJ6/6LQ6/6JE6C".

The number on these tubes has as much to do with when they were made as to do with what is inside them.

73

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