Announcement

Collapse
No announcement yet.

Best place for standby switch on 5F2A???

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Best place for standby switch on 5F2A???

    Working at home today drilling holes in bits of Aluminium for my tweed princeton chassis, thinking, "okay if I make provision for a hole for a standby switch, where is the best place to wire it to? Ahem...", (or mayhem, whichever you prefer):

    1) The B+ supply between pin 8 of the 5Y3GT and the first filter cap?; or

    2) A switch that disconnects the center tap of the HT winding on the PT from the ground?; or

    3) Someplace else?

    And, is it simply a matter of inserting a switch in one of these locations, or do I need to add some other stuff to make it safe?

    The type of switch I'm thinking of is a single pole single throw switch.

    Cheers
    Building a better world (one tube amp at a time)

    "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

  • #2
    I usually put the standby right after the rectifier(s), so I'd choose choice #1.

    I have used #2 before, but one of the engineer types over at the AX84 BBS said that diconnecting the CT of the HV winding messes with the grounding scheme so I don't use that method any more. Makes sense to me.

    chuck

    Originally posted by tubeswell View Post
    Working at home today drilling holes in bits of Aluminium for my tweed princeton chassis, thinking, "okay if I make provision for a hole for a standby switch, where is the best place to wire it to? Ahem...", (or mayhem, whichever you prefer):

    1) The B+ supply between pin 8 of the 5Y3GT and the first filter cap?; or

    2) A switch that disconnects the center tap of the HT winding on the PT from the ground?; or

    3) Someplace else?

    And, is it simply a matter of inserting a switch in one of these locations, or do I need to add some other stuff to make it safe?

    The type of switch I'm thinking of is a single pole single throw switch.

    Cheers

    Comment


    • #3
      follow-up on standby sw location

      FWIW I talked with a few more peeps and decided to go with the HT center tap for the standby switch, and there haven't been any problems related to grounding so far (touch wood).
      Building a better world (one tube amp at a time)

      "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

      Comment


      • #4
        Originally posted by Chuck_Farlee View Post
        I usually put the standby right after the rectifier(s), so I'd choose choice #1.

        I have used #2 before, but one of the engineer types over at the AX84 BBS said that diconnecting the CT of the HV winding messes with the grounding scheme so I don't use that method any more. Makes sense to me.

        chuck
        How does disconnecting the CT "mess" with any grounding scheme?It only lifts the CT,doesnt affect any ground whatsoever.

        Comment

        Working...
        X