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MACO 200


thanks ,,,,,,bioman.......but this one has the 8950,s in it .......dont know if it matters about the sams, or not........but this has 1 has 1-100uf 450vdc and 1- 100uf 450vac caps & they are poped, also the diode, & 1 cap on the drive tube 330uf 25v.off of pin 9 to grd. also poped. is this a polarized plug? looks like someone has put a lamp cord on it , also it had a 25 amp car fuse in it .
 
i'm nt sure if it is a polarized plug or not

the 450VDC caps are probably for the power supply and will need to be replaced along with the one on pin 9

if it was mine i would replace every cap in the box with new ones and at least test all the resistors although i would probably replace them as well

but only if i was sure the tubes were good since 8950s arent exactly common ya know what i mean?

put a 3 prong cord on it with a fuse on both sides and the green wire tied to ground

at any rate me personally i would go through the whole amp to make sure it is SAFE before i'd even think about plugging it in again

i dont know where else to get a schematic for it but it is all pint to point wiring correct? if you felt ambitious you could sit down and redraw the whole thing directly off of the amp if you wanted to

just to keep the details fresh while you were replacing all the caps in it

good luck
scott
 
The amp did not come with a polarized plug. The brown lamp cord is what came originally on it. The schematic on CBTricks is the correct one. You should be able to fix any problem the amp has with it.
The 6LB6 version was one of the early versions. 8950's were next. Replace the 100mfd @ 450vdc caps and while you are at it change the rectifiers in the power supply. HV supply will then be complete. Replace the 330 mfd cap and make sure the 1500 ohm 2 watt resistor is good also.
Always remember the amp has around 900 VDC when one and still lurking in it when off. It will ruin your day to find out the hard way. Most tube testers will not check the 8950's but you can use the settings for a 6LB6 to get an idea what condition the tubes are in.

BC
 

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