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Caps: "To Form, or Not to Form?..."

4/23/2000 9:42 PM
rmike	Caps: "To Form, or Not to Form?..." "...that is [1/3 of] the question." I'm about to finish up my first DIY. It's a tweed deluxe. I have three simple questions: 1) Should I 'form' the caps in the amp by using a variac or something like that? I was under the impression that it IS necessary. However, the tube amp FAQ states that it's NOT really necessary if the caps are less than 5 years old, which I'm sure they are. Any opinions? 2) I've wired in a standby. It's between pin 8 of the rectifier and the first filter cap. Is this ok placement? 3) What do I do with Pin 1 on the two 6V6s? The schematic shows it grounded with the filament pin 2. However, the heater circuit has been modified to later fender standards--running parallel between tubes and using an artificial center tap (2 100 ohm resistors), hence pin 2 is not grounded.... Also, the pinout for the 6V6GT shows nothing on pin 1. Do I still run pin 1 to ground? If so, why? Last, I just wanted to express how valuable this forum is. While wiring this thing up the past few weekends, I've amazed myself at how much I really have learned just by hanging out here the past 2 years! thanks! mike

4/23/2000 9:42 PM

rmike

Caps: "To Form, or Not to Form?..."

"...that is [1/3 of] the question."

I'm about to finish up my first DIY. It's a tweed deluxe. I have three simple questions:

1) Should I 'form' the caps in the amp by using a variac or something like that? I was under the impression that it IS necessary. However, the tube amp FAQ states that it's NOT really necessary if the caps are less than 5 years old, which I'm sure they are. Any opinions?

2) I've wired in a standby. It's between pin 8 of the rectifier and the first filter cap. Is this ok placement?

3) What do I do with Pin 1 on the two 6V6s? The schematic shows it grounded with the filament pin 2. However, the heater circuit has been modified to later fender standards--running parallel between tubes and using an artificial center tap (2 100 ohm resistors), hence pin 2 is not grounded.... Also, the pinout for the 6V6GT shows nothing on pin 1. Do I still run pin 1 to ground? If so, why?

Last, I just wanted to express how valuable this forum is. While wiring this thing up the past few weekends, I've amazed myself at how much I really have learned just by hanging out here the past 2 years!

thanks!
mike

Replies:

peter You probably don't need to form the... -- 4/23/2000 10:24 PM
JC Excuse for using your post to ask a... -- 4/23/2000 10:44 PM
Ray Ivers Cap Forming, Standby Switching, Tube Basing -- 4/24/2000 3:15 PM
Trace Re: Caps: "To Form, or Not to Form?..." -- 4/24/2000 3:29 PM