Tube DIY Asylum Do It Yourself (DIY) paradise for tube and SET project builders.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ Tube DIY Asylum ]

---

[ Alert Moderator ]

---

Why do i have DCV on the 6v6 input of my RH amp?

Posted by DAK (A) on January 25, 2015 at 19:13:13

I just built this stereo RH 6V6 with 6SL7 driver. It uses a CLCLC power supply and with a 5AR4 rectifier provides 280vdc B+. Well after a warm up period, I tested various voltages in the amp and measured 15vdc on the 6v6 input grid. Oddly enough, the cathode voltage is slightly more than this.
OK, first thing to check is the coupling cap which was a .22uf x 600 RTX. This cap was from a previous build but tested ok on my cap tester. So, I pulled the 2 .22uf caps and installed NOS PIO .22uf Westcap. I was disappointed after reenergizing the amp to find the same problem still existed.
I installed the coupling caps by soldering it to pin6 of the tube socket. From there the 220 ohm grid stopper resistor goes to pin5 or G1 of the 6V6. Supposedly P6 is unused on that tube and is actually missing on some 6V6s.
Having 15vdc on the grid can't be good for the amp. So, I am looking for help trying to cure this problem. TIA, Dak

This post is made possible by the generous support of people like you and our sponsors:

Parts Connexion

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---