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Multi-Purpose Booster/Buffer PC Board



This is the complete schematic for the circuit that is contained on the AMZ Multi-Purpose PC Board. None of the example circuits will utilize every part that has been positioned on the board. Extra parts have been included to add flexibility and options to the boards. The basic idea is to create a single pc board that can be used to make multiple projects, including boosters, buffers and more.

If a part is not shown on the schematic or in the parts list for one of the circuits, then it is not required for that project and can be left empty on the pcb.

It is designed for use with silicon or germanium transistors, and NPN or PNP polarity. This board is the ultimate in versatility!

The pcb measures 1.5" x 1.3". The diagram to the left shows the basic connections to the Multi-Purpose pcb.

The circular object immediately above the "Gr" designation is the transistor location (Q1). It is large enough to accomodate even a TO-5 package. The small tab on the bottom left edge is the indicator for the emitter lead.

When using a TO-92 bipolar transistor (E-B-C), it should be oriented with the flat side facing to the right. This puts the emitter at the bottom and the collector at the top. The base lead will have to be bent slightly to fit in the middle hole.

Note that a BC108 style transistor is C-B-E and should have the flat side facing left. Always check your transistor datasheet to find the proper pin designations.

There are a few more special items to note on the pc board. First, there is a small circular pad immediately above the printed R3 designation on the board. This pad is only used for a couple of circuits and is ignored the rest of the time.

Second, the R5 position has three pads in the middle between the resistor pads. These are for an optional trimpot that is used as the R5 resistor for some circuit variations. If the trimpot is not specified, the pads are ignored and the resistor soldered across the pads above and below the R5 box.

Also, polarity signs have been added for C2, C3 and C4; they are not on the pcb. The positive side of electroytics should be oriented to the plus signs as required. These markings are correct for NPN versions and n-fet or n-mos circuits.


The circuit shown here is a basic bipolar transistor booster exactly like the ancient LPB-1. It is a simple design with lots of gain. The R10 potentiometer is mounted off the pc board.

Parts List

R3 - 470k
R4 - 47k
R5 - 10k
R6 - 390 ohms
R9 - jumper
R10 - 100k audio taper
C1 - 0.22uF
C2 - 1uF
Q1 - NPN silicon transistor (2N5088, 2N3904 or similar)

All resistors are 1/4w and capacitors are in uF.

Many more circuits are detailed in the link that is sent when you order the AMZ Multi-Purpose pc board and you can build any one of the boosters or buffers for some great tone.


  • Silicon Transistor Booster
  • AMZ Muffer
  • AMZ Muffmaster
  • A Dirty Boost
  • AC128 Germanium Transistor Booster
  • PNP Rangemaster-type Treble Booster
  • Germanium Transistor Buffer
  • Jfet Transistor Booster
  • Jfet Transistor Buffer/Line Driver
  • Mosfet Transistor Booster (not the AMZ Mosfet Booster)
  • Mosfet Buffer
  • Power Supply Filter
  • and MORE!

Note: Only one circuit can be built on each pcb at one time, i.e. a booster and a buffer would require two boards.

Place your order for one of these versatile pc boards.

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