6V6 Rocket build low output

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Littlewyan
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Location: UK

Re: 6V6 Rocket build low output

Post by Littlewyan »

Well, this is an odd situation!

So just to confirm, do the power valves actually break up at all? Or is it just the PI breaking up?
valveandsound
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Joined: Sun Jun 04, 2017 3:46 pm

Re: 6V6 Rocket build low output

Post by valveandsound »

update:

I removed the cut control, and gained an additional few watts of power. At this point, it puts out about 13 watts before clipping. That still doesnt seem right for a pair of 6V6 in cathode bias?
valveandsound
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Re: 6V6 Rocket build low output

Post by valveandsound »

im fairly certain it's just the PI clipping.
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Littlewyan
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Re: 6V6 Rocket build low output

Post by Littlewyan »

It's most likely the connections in the PI on the cathode. Check each connection from component to component with your meter and ensure they all read zero ohms.

Not sure what else to offer until we see some pics
dbeasley
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Joined: Fri Jul 28, 2017 3:07 am

Re: 6V6 Rocket build low output

Post by dbeasley »

Ok so I had to step away from it for a while to clear my head.

So I think I've realized my error here.


With an 8 ohm load connected to the 8 ohm tap I get 9 Watts of power. With the 8 ohm tap connected to a 16 ohm load I get 18 watts slightly clipped.

I double checked the color code schemo and I wired it correct, however there must have been an error when they terminated the trafo at the factory!

I'm going to reinstall the master and cut control and see how it sounds.

Sent from my Moto G (4) using Tapatalk

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Littlewyan
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Re: 6V6 Rocket build low output

Post by Littlewyan »

It's not a great test but measure from ground to each of the taps. The resistance will be extremely low but as you move up the taps from 4 to 16ohms you will see it increase.

There is another way of testing it using AC Voltage from the heater winding but I've never done it.
dbeasley
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Re: 6V6 Rocket build low output

Post by dbeasley »

Right - counting the turns ratio with a fixed AC signal at the input.

I knew how to do this but I didn't even think about it. Good thinking Wyan!

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Littlewyan
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Location: UK

Re: 6V6 Rocket build low output

Post by Littlewyan »

I must admit I've never done it! So good luck :D
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