Amplifier Kit Using K-502 Tube

The K-502 tube amplifier kit was designed as a piece of pine that can be mounted on an amplifier although it would be more suitable to put it in a box.

During the construction, all the cutting and painting are often the hardest part of any amplifier project. This is why the transformers are mounted on a solid plate then attached this to the grill top. The only changes to the circuit were to replace the standard 0.22uF capacitors with good quality orange drops. A stepped attenuator is used to replace the volume potentiometer, which will make a huge difference to both sound and control.

There are 4 super-bright LEDs for each corner used for the lights and a computer case fan with more blue LEDs. A 12V PSU is mounted on a neat little PCB to provide the power and to turn it all ON, a rocker switch at the front is implemented. To reduce the mains to 110V, a step-down transformer is required. The creation of this kit was worthy although the overall cost for this tube amp project with the enclosure and upgrades was twice that of the original cost.

Rest of the project