Circuit Boards for Tube Amps

Guitar Amp - Home
5F1 Circuit
Guitar Amp Circuit Board
Guitar Amp Chassis
Guitar Amplifier Cabinet

Circuit Boards

Installing Turrets
Turret Staking Tool
Soldering Circuit Board Components
Circuit Board Layout

Guitar Amp Circuit Board

Circuit Board

When it comes to an all valve amplifier there is really not that much to it. The circuit board is going to hold the basic electrical components such as resistors and capacitors. The circuit board does need to be of a non-conductive material capable of high voltages and fairly high temperatures. For my guitar amp circuit board I used a 1/8 inch thick piece of phenolic fiberglass reinforced material. This is very sturdy stuff and can be found at many sites on the Internet.

Point to Point Wiring

Most guitar amps from the 70’s and prior were built using the point to point wiring method. Point to point wiring is a hand assembled process that really shows the craftsmanship of the era. Tiny pieces of metal called turrets are swaged to the circuit board and used to secure the wires and electrical components in point to point wiring (PTP). Sometimes an eyelet contact is used.

Installing Turrets and Eyelets

Before installing any turrets or eyelets a layout pattern must be drawn on the amplifier circuit board. Once the proper pattern is set all the holes for the turrets can be drilled. Swaging tools can be purchased on the web usually running around $25.00. I came up with my own swaging tool that didn’t cost anything. A swaging tool is simply a device that holds the turret firmly against the circuit board and then flaring the opposite end of the turret with the flaring end of the swaging tool. It’s kind of hard to picture so see the photo below. My homebuilt swaging tool consists of an automotive bolt end drilled to the exact size of the turret. Mount the drilled bolt in a large vise and set a turret in the bolt. The circuit board can now be laid on to the turret. Using a punch with a ground end filed to a point carefully flare the turret end by hitting the punch with a hammer. A couple of taps should be sufficient. Wah-lah, the turret is installed. It should be very firm and will last a long time.

Soldering and Components

Once all the turrets are swaged in place each electrical component can be soldered in place. To solder a connection wet the tip of the soldering iron with a little solder then make contact with the components to be soldered. Add solder to the electrical components being soldered until the solder flows freely and forms a nice smooth joint. Soldering a joint should be relatively quick. The soldering iron should not remain in contact for more than a few seconds to avoid damage to components.

Electrical Shock Hazard !

Privacy Policy ©2013