HLMP-6000 and octal socket.

[richmi]

Hello all,

I am planning to build the Crack stock when it arrives. However, I would like to make the necessary modification to the chassis plate to accommodate an octal socket before I start, so that I do not have to produce metallic debris once everything is assembled. My experience with the Extended Foreplay conversion to 6SN7 taught me protecting the circuit after the fact is not the easiest and most pleasant thing.

It is a good thing that one can now download the manual at the time of purchase, as one can get familiar with what to expect.

I see that pins A3 and A8 are each connected to the socket's centre pin via a HLMP-6000 led and then to 3L.

Octal sockets do not have a centre pin. I found a socket that has solder lugs on the mounting bracket. I thought that I could use these to solder each end of the red led and then make the connection to 3L. Reading different posts on the use of a 6SN7 instead of a 12AU7, I seem to understand that this is a no-no, perhaps because the red led would be connected to ground at two places? Can anyone confirm this?

I also have a Belton socket. The diameter of each is pretty close (0.38mm difference). I wonder if I could just take the mounting bracket with the solder lugs, remove enough metal to get rid of the screw holes and transfer it onto the Belton socket, making sure that it is isolated from the chassis. Then, instead of having a socket with a centre pin, I have a socket with a ring with solder lugs.

The reason for wanting to convert to 6SN7 is that I have many of that tube and very few 12AU7, and it seems easy.

It has been nearly 6 years since I build my Bottlehead kits, and I am surprised that I now feel that I understand what is going on as I read the manual. Everything was so mysterious 6 years ago.

It is amazing how Bottlehead has evolved since the last time, with new products and refinement. It is passion, intelligence and intuition at work.

Sincerely,

Richard

[Paul Birkeland]

In the world of perfect engineering and exact decisions, we would give you a really hard time about using those socket mounted lugs because they could create ground loops. 

I don't honestly think doing that will cause any problems.  You can also use one HLMP-6000 to either cathode, then wire the cathodes together, if that is easier for you.

If you have the patience, you can enlarge the terminal strip hole at the front of the chassis to accomodate #4 fiber shoulder washers, then insulate the ground lug of the front 5 lug strip, making one of the socket lugs your new ground connection. 

-PB

[2wo]

You could use one of these to replace one of the socket mounting screws. It would take the place of the center lug...John

http://www.partsconnexion.com/solder_posts_tamadenyo.html

[richmi]

Thanks PB and John,

I will isolate the terminal strip that sits next to the 9-pin socket from the chassis plate. I think that this is the easiest solution. I do have some fiber shoulder washers.

Richard