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Tallman
Posted on Wednesday, November 26, 2003 - 4:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Hi,

Need this info so i can get me some extra's at maybe a good bargain.Thanks for the help!

Tallman Happy T-Day!
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Scrapiron63
Posted on Wednesday, November 26, 2003 - 6:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
8950s, one driving 3.
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Tallman
Posted on Thursday, November 27, 2003 - 9:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
8950's is incorrect.It is more like 6JE6's without a driving tube.

Thanks anyway. Tallman
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Tallman
Posted on Thursday, November 27, 2003 - 6:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Hi,

But i'm not certain about the 8950's...What should i expect in output with good tubes in high.Like - 80wt dead key with 325 in swing with the 4 tubes..I would love to know the basic spec's on the Maco 200.

Thanks for the assitance.. T-man
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Scrapiron63
Posted on Thursday, November 27, 2003 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Maco did put 6LB6s in a few of the maco 200s and maco 300s, but most used the 8950s. They also used 2057s in some of the 300s.
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2600
Posted on Friday, November 28, 2003 - 11:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
How to tell which family of tube types your Maco 200 was built (or modified) to take?

You'll have to remove the bottom cover. Don't touch the big filter caps. Maco almost never bothered with bleeder resistors. They can pack a whallop for weeks of being turned off.

Each of the four tube sockets has twelve pins, with a solder lug for each pin under the socket. The "gap" in the pin circle is where the heater connections are. The pin on the left of the gap is pin number 1. The one on the right of it is pin 12. If ALL FOUR sockets have one of these two pins grounded, the sockets are wired for types 8950 or 2057, 12.6 Volt heater-type tubes. it doesn't matter which of the two is hooked to ground. Maco wasn't too consistent with that kind of stuff from one batch to the next.

If ONLY TWO of the four tube sockets has EITHER pin 1 or 12 jumpered to ground, then it's wired for 6.3-Volt tubes, like 6LR6 (wimpy), 6LB6 (meaner) 6LF6 or 6KD6. There are other type numbers that may work, but most of those are smaller. Not a good choice for a Maco.

73
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Tallman
Posted on Saturday, November 29, 2003 - 1:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Thanks, Scrapiron & 2600 and all others.This is very helpful.I will determine now the best tubes to be used in this maco 200...

Happy Holidays! Tallman

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