Ramsey Electronics QAMP30 manual Transistor bend pix

Models: QAMP30

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Transistor bend pix

These last four parts (R8,9 and C11,12) form parasitic suppression networks across each transistor to suppress any tendency for high frequency oscillation in the power amplifier.

ˆ32. Install C3, another .1 µf disc capacitor (marked .1 or 104). Both of these capacitors bypass the center tap of the ferrite transformers to ground. Bypass means to provide a low impedance path to ground.

ˆ33. Install C1, 100 to 220 µf electrolytic capacitor. Be sure to observe correct polarity.

ˆ34. Install C4, 330 ρf disc capacitor (marked 330 or 331).

ˆ35. Install C5, 560 ρf disc capacitor (marked 560 or 561).

ˆ36. Install C6, another 560 ρf disc capacitor (marked 560 or 561).

ˆ37. Install C7, another 330 ρf disc capacitor (marked 330 or 331).

ˆ38. Install wire jumper, JMP1. Use a scrap piece of component lead wire.

Transistor bend pix

ˆ39. Locate the MOSFET power transistors and prepare the leads for insertion into the PC board. Bend down the two outside leads about 1/8" from the transistor body and the center lead about 3/16" from the body.

ˆ40. Mount the transistors and heatsinks to the PC board using the 4-40 screws and nuts. Solder all transistor leads. Note that the heatsinks may look slightly different from the ones shown.

QAMP-30 • 9

Page 9
Image 9
Ramsey Electronics QAMP30 manual Transistor bend pix