HF PACKER
AMP
V4R6
Page 31
In my experience the bend should be a little bit closer to the
body than shown in the photo above.
MOSFET Attachment to the Circuit Board
The MOSFETs should be bent very close to spot where the
leads neck down. To space the MOSFETs, use the circuit
board with the 4 corner mounting spacers installed. On a flat
surface feed the MOSFETs from the backside thru the
mounting holes of the circuit board. Observe that the
MOSFETs are flat against the table and that the mounting hole
of the MOSFET aligns with the access hole on the circuit
board. Solder the MOSFETs in place on the circuit board.
Inspect the solder job on the back side and reheat as required.
Circuit Board and Case Assembly Procedure
Place the PSU End of the AMP Module back into the case
towards the rear panel and then lower the remainder of the
circuit board down to the case. The slot in the circuit board
fit over the front panel switch wires. Arrange the other
cables to not interfere with board mounting.
Attach the circuit board from the top of the case using four
black 4-40 x 3/16 inch screws.
MOSFET Alignment over Heat Sink Holes
•
Micro-adjust as necessary by moving the body of a
MOSFET so that the hole in the MOSFET matches the
threaded mounting hole in the heat sink.
Do not over-tighten the nylon screws. You could shear
off the head with too much torque.
Insert the two black Nylon 6-32 x 5/16 inch length Socket
Head Cap Screws through the MOSFET holes into the
tapped holes on the heat sink using the 7/64 inch hex head
tool. Tighten the screw until resistance is encountered.
Inspect the screws to make certain that it they are firmly in
contact with the MOSFETs. Peering into the heat sink, the
tips of the nylon screws should barely be visible on the pin
side of the heat sink if properly installed.
Use the multi-meter to measure ohms. Connect one probe
to chassis ground and the other probe to any pins on the
MOSFETs. You should have a very high megohm or
infinite reading on the meter. This measurement is made
before any cables are attached to the board.
Содержание PackerAmp V4
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