Re: grounding case of 6j5
It'll work much better. As for how, make certain that the metal envelope is the most negative part of that tube. This will usually be the case if it's connected conventionally: plate to positive DC rail + cathode bias. Even if using fixed bias, it will still be at the same potential as the cathode, and that's good enough. If the case isn't more negative than the cathode, it will behave as another anode, and that'll likely lead to problems.
Sy: WTH're you talking about? With those metal Octals, pin #1 is connected to the metal case.
dsavitsk said:Does anyone have any suggestions on whether it is necessary (for safety reasons) to ground the case (which is metal) of a 6j5, and, if so, how to do it?
-d
It'll work much better. As for how, make certain that the metal envelope is the most negative part of that tube. This will usually be the case if it's connected conventionally: plate to positive DC rail + cathode bias. Even if using fixed bias, it will still be at the same potential as the cathode, and that's good enough. If the case isn't more negative than the cathode, it will behave as another anode, and that'll likely lead to problems.
Sy: WTH're you talking about? With those metal Octals, pin #1 is connected to the metal case.
Re: Re: grounding case of 6j5
That's a very good point. Scrub my recommendation of tying the can to the chassis; tie it to an AC ground with a lower DC potential than the cathode. Often, that will be the chassis, but not always.
Miles Prower said:If the case isn't more negative than the cathode, it will behave as another anode, and that'll likely lead to problems.
That's a very good point. Scrub my recommendation of tying the can to the chassis; tie it to an AC ground with a lower DC potential than the cathode. Often, that will be the chassis, but not always.
Not quite right
If the metal envelope is at the same potential as the cathode, it cannot act like another plate. In all situations, you can connect pin 1 to the cathode. From my experience, this is preferred - I've used the 6C5, 6J5, 6J7, 6SJ7, 6F5, and 6Q7 in many projects. When Rk is bypassed, it's ok to ground it.
Joel
If the case isn't more negative than the cathode, it will behave as another anode, and that'll likely lead to problems.
If the metal envelope is at the same potential as the cathode, it cannot act like another plate. In all situations, you can connect pin 1 to the cathode. From my experience, this is preferred - I've used the 6C5, 6J5, 6J7, 6SJ7, 6F5, and 6Q7 in many projects. When Rk is bypassed, it's ok to ground it.
Joel
Re: Not quite right
Thanks for the suggestions.
I should have too as i now notice pin 1 connected to the case.
I was going to use these in an ultrapath design, so I'll try pin 1 to ground and to the cathode to see if there is a difference.
Thanks for the suggestions.
SY said:I should have looked at the data sheet.
I should have too as i now notice pin 1 connected to the case.
Joel said:If the metal envelope is at the same potential as the cathode, it cannot act like another plate. In all situations, you can connect pin 1 to the cathode. From my experience, this is preferred - I've used the 6C5, 6J5, 6J7, 6SJ7, 6F5, and 6Q7 in many projects. When Rk is bypassed, it's ok to ground it.
I was going to use these in an ultrapath design, so I'll try pin 1 to ground and to the cathode to see if there is a difference.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
- Home
- Amplifiers
- Tubes / Valves
- Grounding case of 6J5