Originally Posted by MIKELAP
Thats the kind of explanation i would like to get with pictures related to the socket mod for the double triode mod because there still things that are not clear related to soldering pins and deactivating the same pins at the base dont know what that means exactly . When somebody has the full picture and pictures it will be great meanwhile stocking up on equipement to do this thing.and practicing my soldering.
Hope this explanation will help a bit....
When we insert a 9-pin 6DJ8 or 6BQ7A into a 7-pin adaptor, we have the following:
Tube pin assignment -> unmodified adapter -> Little Dot pin-hole assignment
Tube pin 8 (cathode) -> pin-hole 7 (screen/suppressor grid)
Tube pin 7 (grid) -> pin-hole 6 (screen/suppressor grid)
Tube pin 6 (plate) -> pin-hole 5 (plate)
Tube pin 5 (heater) -> pin-hole 4 (heater)
Tube pin 4 (heater) -> pin-hole 3 (heater)
We are fortunate that tube pins 4, 5 and 6 line up perfectly. However, we are not so lucky with tube pins 8 and 7. The Little Dot assigns the grid to pin-hole 1, not pin-hole 6; and the cathode to pin-hole 2, not pin-hole 7.
So we modify the adapter. We connect tube pin 8 (adapter pin 7) to adapter pin 2 to reroute the cathode to pin-hole 2, and tube pin 7 (adapter pin 6) to adapter pin 1 to reroute the grid to pin-hole 1.
Now that adapter pins 2 and 7 are connected and pins 6 and 1 are connected, we do not want pins 6 and 7 to extend out of the bottom of the adapter and into pin-holes 6 and 7 in the Little Dot socket. So we cut them a bit short. When you look at the bottom of the adapter, you will see only 5 pins, as the other two have been shortened.
Hope this helps. :)
PS: Very frankly, it was quite a struggle to put my adapters back to together after modification, but everything is working perfect. Therefore, I am very reluctant to take them apart in order to take pictures as I don't want to risk breaking them somehow. (>_<)