Still remember my Aikido project? Until now, I’m still using Octal socket (since most of my rectifiers are Octal based, like 5U4, GZ37, etc).  Few weeks ago, I was poisoned with RGN Rectifier. Well, I knew this tube for long time, but just that time was poisoned badly. Have no choice, got to get one at eBay.

How do I use it on my Aikido? I’m too lazy to modify the socket, I decide to create a DIY Socket Converter, from B4 to Octal.

Most European tubes use this Socket. But in this project, I will specify the usage for RGN Rectifier tubes. Most of my RGN will use 4 Volt heater, while the standard Octal will use 5 Volt. What should I do? Piece of cake, just put 2 Resistors in both heaters line. Considering the RGN will consume around 1 A current, then 0.5R will do perfectly to drop from 5 Volt to around 4 Volt (I prefer to use 0.33R each to drop to 4.3 Volt, in case my main line drop a little bit at night).

Below is the necessary parts 😉

An empty Octal socket, B4/B5 Socket, and two 0.33R resistors.


How do we create the converter? Basically, you just need to re-route the correct pins from Octal to B4. On Octal socket, the pin #2 and #8 are heaters, while the plates are pin #4 and #6. On B4 socket, the two top pins on the lower triangle are heaters, while the rest two are plates.


Here is the complete configuration of my DIY Socket Converter. Each heater will have 0.33R resistor, while the plates will connect directly to the correct pin. I use silver stranded wires with teflon insulated for a perfect transfer on the plate line. Quite a neat work…


Soldered to empty Octal socket. Make sure you put it on the right pins. Check the pin layout diagram to confirm 😉


Voila, a complete converter, with RGN Rectifier plugged in.


The RGN with the converter plugged in to my Aikido. A little bit weird with that tall, but who cares? 😉


The beautiful mesh plate of RGN 1054. Despite its good looking, it has superb sounding also.


My “new” Aikido, with RGN 1054 Rectifier, currently used as capacitor burn-in bench.