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previous: Ricky I built a 2-6V6,long tail phase inv... -- 4/20/2000 4:31 AM

Re: creating rectifier sag

4/20/2000 2:52 PM
Bruce	Re: creating rectifier sag You can try putting a 130 to 220 ohm 10 watt resistor in series with your B+ right after the rectifier tube's first filter cap and before the OT tap. Or you can use that same resistance in series with the lead that feeds just the OT. At say, 70ma of current drain, the 130 ohm resistor will drop about 9v and the 220 will drop about 15v. When you crank up the amp, the current will increase and the voltage drop across that resistance will be higher. You might get peaks of twice that current so twice the voltage drop. Keep in mind that voltage drop gets turned into heat so don't use a cheap little 2 watt resistor! And an old RCA 5Y3 is the saggiest one out there! Bruce

4/20/2000 2:52 PM

Bruce

Re: creating rectifier sag

You can try putting a 130 to 220 ohm 10 watt resistor in series with your B+ right after the rectifier tube's first filter cap and before the OT tap. Or you can use that same resistance in series with the lead that feeds just the OT.
At say, 70ma of current drain, the 130 ohm resistor will drop about 9v and the 220 will drop about 15v.
When you crank up the amp, the current will increase and the voltage drop across that resistance will be higher.
You might get peaks of twice that current so twice the voltage drop.
Keep in mind that voltage drop gets turned into heat so don't use a cheap little 2 watt resistor!

And an old RCA 5Y3 is the saggiest one out there!
Bruce

Replies:

Ricky I'm using a phillips 1980's JAN 5y3... -- 4/20/2000 5:02 PM