Picked up the Golden Falcon 1kw amplifier that uses 10 big bad 8908 tubes. I already knew something about 8908 as they are used in the Hygain Footwarmer which I have one now and have worked on in the past. BTW that 2 tube Hygain Footwarmer is one bad bad amp. I thought the 6lw6 was a 6v replacement for the 12v filament 8908's but I was somewhat wrong. After much research, here's what I found:
Almost all common sweep tubes like 6lq6, 6lf6, 6je6c, 8950's and many may other variants are rated at 30 watts dissipation or less. The 'sweep' tube was used in old tube TV sets from the tube TV era. It's purpose was to drive or make the 'sweep' of the dots or pixels across the screen, hence the term 'sweep tube'. During the tube TV days, with millions of tube TV's out there, sweep tubes were cheap and plentiful. When amp makers were designing amps at the time, there were some transmit tubes available, but they were not as cheap and plentiful as TV sweep tubes were. Hence at the time, some Ham amps and most CB amps made took advantage of the price and availability of the TV sweep tubes. Hams may claim to hate sweep tube amps and call them no good now, but if you look at the actual reviews from Hams on the Ham amps that used the same tubes and same design that most CB amps used, the Ham sweep tube amps generally got great reviews, but of course, the CB amps suck..... even though same tube and same design LOL.
So normal sweep tubes are 30 watts dissipation or less, but the biggest and baddest sweep tube made at the time was the 6lw6 tube. It was rated at 40 watts instead of 30 and it was just bigger, fatter, healthier, and more meaty than the common sweep tube. The 8908 is the 12v filament version using the same 8 pin Octal base but be careful, pinout is different. BTW, the 8950 is the 12v filament version of the 6lf6 tube. Since it was available and cheap at the time, some amp makers, like Hygain and Golden Falcon used the big bad 40 watt tubes instead of the more common generics. Later when tube TV's went extinct, GE had many of the 8908's left and Maco who was building multi tube amps using the 12 pin compactron base tubess by the thousands, talked GE into making the 8908's using the 8 pin Octal base into the 12 pin Compactron base and the M "maco" 2057 was born. The insides of the M-2057, 8908, and 6lw6 are identical but the base of the M2057 is 12 pin, and the 8908 and 6lw6 are 8 pin Octal. The M2057 and 8908 are 12v filament and the 6lw6 is 6v filament. The pinout is different on all of them.
6lf6 6v 30 watt 12 pin compactron base
8950 12v 30 watt 12 pin compactron base
6lw6 6v 40 watt 8 pin Octal base
8908 12v 40 watt 8 pin Octal 'different pinout than 6lw6'
M-2057 12v 40 watt 12 pin compactron base same pinout as 6lf6 8950

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