Maco Brute ll

[YardDog]

Might be getting one in the next couple weeks. It's getting new tubes, two 6lq6 drivers into five 24lq6. It's been working fine but he wanted new tubes in it before he would sell it to me. Haven't seen one for sale in years so I don't know what a good price would be. If it's not crazy high I'll be bringing it home soon.

 

[Shadetree Mechanic]

The tubes aren't cheap, and probably worth more than the amp by itself. Check out some tube prices and add up their value, would probably be a good starting point. People buy equipment to resell the tubes. And often junk the equipment in the process.

 

[secret squirrel]

I would have never thought technology would come to the point that we are in search of 30-40 year old equipment pieces, because they no longer make things the way they used to do it. I remember my uncle had a big tube tester console that he got from a US Steel mill back in the 1970s. No one would have ever thought we would be treating the tubes like money 40 years later.

 

[Shockwave]

The price of the tubes alone makes me question the story being told. Nevermind it would be extremely difficult to even find a matched set of tubes, at any price. If the price is reasonable and the seller can show a recent receipt for the so called new 7 tubes, buy it. If there is no receipt for the tube purchase, assume the tubes are as old as the amp and beware.

 

[nomadradio]

Has to be a heavily-customized box. Never have seen a Maco with 9-pin tubes. Every one I know about used tubes with the 12-pin base.

Hopefully it was redesigned by someone with a clue, and includes the circuits that allow the tubes a decent service life.

And if it was modified to be a hot rod that squeezes every Watt from the tubes, that's what we call a "nightmare box" around these parts.

Best of luck and 73

 

[Shockwave]

Has to be a heavily-customized box. Never have seen a Maco with 9-pin tubes. Every one I know about used tubes with the 12-pin base.

Hopefully it was redesigned by someone with a clue, and includes the circuits that allow the tubes a decent service life.

And if it was modified to be a hot rod that squeezes every Watt from the tubes, that's what we call a "nightmare box" around these parts.

Best of luck and 73

Interesting point. The only exception I could find online was a very old Maco 500 and that looks like it used the smaller 6KV6, 6JB6 or 12JB6, 9 pin version with NO plate cap. Every one I've seen in person used either 8950 or M2057. Once you talk GE into custom manufacturing your own tube, why buy another?

 

[AudioShockwav]

I have only seen one other Brute II and I swear it had 8950 tubes in that one , it was about 30 years ago.
It's funny, I remember going to Thrifty drug store and getting tubes, they had the big standing tube tester with a cabinet stuffed full of nice fresh new tubes.
Back in the day.

73
Jeff

 

[Shockwave]

I have only seen one other Brute II and I swear it had 8950 tubes in that one , it was about 30 years ago.
It's funny, I remember going to Thrifty drug store and getting tubes, they had the big standing tube tester with a cabinet stuffed full of nice fresh new tubes.
Back in the day.

73
Jeff

I Remember in the late 1970's and early 80's, locals were killing the Radio Shack stores with their "Lifetime Warranty" on all tubes. That warranty worked fine for Radio Shack when one sweep tube went into the TV and they charged you for two of them, in order to cover their warranty. You should have seen the look on the store managers face when you'd go in 6 months later with ten, flatter than a pancake.

Ten would do 1kw no problem. But, if you pushed them with a driver like a "JB", it would do 1,700 for several months. When it dropped down noticeably, hit it with twice the drive and you'd get another month before it couldn't produce any peaks. Some stores starting getting wise and soon, the name changed to "Long Life" tubes, using the same logo, so no one knew the difference until they needed the no longer existent warranty.

 

[YardDog]

Starting to wonder if this isn't a unicorn. I've found one video and a handful of pictures but no other documentation that it exists. Several opinions on this forum that it has been modified and they may be right, but opinions are just that. I've known this guy for 30 years and pretty sure he wouldn't throw that away over a set of tubes. He's owned the amp for decades and said the new tubes being delivered are the closest match he could find for what was in it when he bought it. Sure would be nice to find a schematic, but apparently it doesn't exist. So modified or not it's a cool old box. Really clean inside and always sounded great on the air.

 

[Shockwave]

If you can key it for at least 30 seconds without the outside metal plates of the tubes turning red hot (only center filament should be orange) and the price is right, try it. The panel meter appears to have been changed too. The good news is, it really didn't take much effort for someone with skills and few "extra" parts, to improve those amplifiers. If the person took the time to get the bias right, it may even make the tubes last longer than before. If the plates turn red, pass on the deal.

 

[sunbulls]

I would have never thought technology would come to the point that we are in search of 30-40 year old equipment pieces, because they no longer make things the way they used to do it. I remember my uncle had a big tube tester console that he got from a US Steel mill back in the 1970s. No one would have ever thought we would be treating the tubes like money 40 years later.

"They no longer make things the way they used to do it." Many things were made better in the past, but IMO that never applied to CB amps. One of the few essential tools needed on a CB tube amp was a rivet gun.

 

[barefootindian]

Sure if the amp boxes were riveted then how it the world could they be easily "modded"? ( Tongue firmly in cheek)

 

[nomadradio]

Varmint base amplifiers were originally sold with the bottom cover held in place by pop rivets. Top cover had four machine screws, but if you wanted access under the chassis deck, you had to drill out the rivets first. Pretty sure it was a warranty strategy. If the rivets were still intact, nobody had 'tampered' with the circuitry.

73

 

[sunbulls]

Pretty sure?
Certain Is Better - Tracy Morgan

 

[Shockwave]

Varmint base amplifiers were originally sold with the bottom cover held in place by pop rivets.
73

How'd you like that class C "super mod" switch? With the flip of that switch on my old XL-750, I could be the dirtiest signal on the band. Nothing made AM jump down into RF cutoff faster, or SSB sound more crunchy, than that switch. That thing would knock an IMD test, right off the charts.