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NAD: 1960 Rocket R-12
#1
I had the itch for an Ampeg.  I like octal preamp tubes.  I initially thought this one was a '59 model but, according to the serial number, it appears to be a very early 1960 model.  It was a painful wait but worth it.

I got it out of the box and styrofoam peanuts went everywhere.  Please don't use peanuts for packing material.  I gave it a quick once over and plugged it in.  Not bad but a bit noisy.  Not as much gain from the preamp but I can live with it.

I took it apart and started cleaning.  I tested the 6V6 tubes but they were the only ones I could test with my Orange tube tester and they tested good.  Not perfectly matched but pretty close.  I cleaned the tube pins and sockets and put everything back together.

I plugged it back in and it was MUCH quieter.  I attribute this to cleaning the pins and sockets.  The tremolo is faster than I would like.  I'm going to have to research it and figure out which resistor to change to get a slower tremolo speed.  Does anyone know the values of the red Astrons?  I can only see the marking for one which is .02

Behold, my first Ampeg!

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#2
What a beauty! Nice job.

Those red Astrons are 0.02 as you noted, they're all the same from what I can see. They are the coupling capacitors between your phase inverter and your power tubes, as seen in the third schematic picture you posted, on the left side.

You're saying that the tremolo is too fast even at its slowest setting? I guess that resistor would be the 120K between the two 0.05 caps leading to the Speed pot (0.5M) so I suppose you could monkey around with that one a bit to get it to your liking... I don't know oscillating circuitry well enough to recommend a value, but I guess I'd get a couple larger and smaller and see what works?
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#3
Beautiful amp! I love the navy random flair era.

I would check your tremolo caps, the circuit is almost identical to later G12 era ampegs, and I can tell you there that the Tremolo isn't super fast.
if the value of your caps is dropping, you would see higher frequency. best to check that that circuit is behaving properly before you jump to modification.

-Steve
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#4
Hey, thanks for the comments. The tremolo isn't CARTOON CRAZY fast it's just that it seems like it should be slower at its lowest setting. I've gotten some suggestions on a couple of other forums that recommended a different value for the white capacitor grouped with the two green Cornell-Dubliers. That should slow it down a bit.
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#5
Wow! That is a real beauty. the Random Navy Flair is also my favourite era for Ampegs. I have a 1961 M12 and would so like to find one of these Rockets or a Jet from the same period. Congratulations. If you ever decide that the amp is not for you, please shoot me a PM. Congratulations.
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