FET Preamp with LND150

Above, the saturation region starts at the knees on the left. We`re interested in curves for negative gate voltages (depletion mode). Note that this device also operates in enhancement mode (with positive bias)! Flexibility. The construction method for this preamp is quite flexible. You can use point-to-point wiring with terminal strips, perfboard
FET Preamp with LND150 - schematic

, or a PC board. I recommend perfboard, such as Vectorbord ®. Look for the type without copper traces. Use the general-purpose type with holes that are 0. 042-inches in diameter. These holes should have 0. 1-inch spacing. Building the circuit. Unless you must fit the circuit into a cramped space, don`t be stingy with the board. Be sure to allow for mounting space around the project. This circuit should then fit on a two-by-two or two-by-three inch board. Run bus wires across the top and bottom of the board`s backside. Loop the ends of the wire through the last two holes in the board. The loops should poke out the top or component side of the board. While testing, you can connect these loops to your power source. Connect off-board jumpers to push-in stakes. (Vector ® makes these stake terminals. I suggest part T42-1/C. Such hardware is available from Mouser. ) Components mount on the top, with leads poking through the holes to the back of the board. Most of the wiring runs across the back of the board. Otherwise, build the circuit as nearly a literal copy of the schematic. That is, the power bus becomes the top of the board. Mount the FET halfway between the ground and power buses. Tack solder resistors between either power bus and the FET as appropriate. You can mount the board on standoff bushings. Most hardware stores stock such bushings. Slip the tiny PC board into a quiet, cool corner of the amp cabinet. Mount the board...

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