[1000mp] Instructions for InRad Key improvement mod in Field

[Art Searle W2NRA]

Since the instructions for the InRad Key
improvement mod were so wrong in the disassembly
area for the Field I am going to try to note my
experience from memory.  In general if I specify
front or back on a board I am referring to the
board's orientation in the radio with the knobs
toward you.  Left and right is as the board lies
in front of you.



Filter board - (the easy part)



1)                 Remove all of the cover screws,
top, bottom, side and remove the handle.

2)                 Turn the radio over and remove
the bottom cover.

3)                 Position the front of the radio
towards you.

4)                 Locate the filter board.

5)                 Remove the 2 ribbon cables on
the left side of the filter board.  Contrary to
the InRad there is no retaining collar, they just
pull out.  There is no need to remove any other
connections.

6)                 Remove all of the screws from
this board

7)                 Place a folded towel on the
back part of the radio and gently fold the filter
board over.

8)                 Follow the InRad instruction on
preparing the cap and resistor in parallel and
mounting.

9)                 Reverse your steps and place
the bottom cover back in place but don't put the
screws back in and turn the radio over.



RF board - (the hard part)



1)                 Remove the top cover.

2)                 Remove the 2 screws that hold
the fan to the heat sink.  They are to 2 screws
farthest away from you on the fan brackets.

3)                 Lift out the fan.  The wires
are long enough to lay the fan next to the left
side of the radio.

4)                 Locate and remove 2 screws on
the left side of the radio (I do not mean left
side on top, I mean left side) the hold the heat
sink assembly (the heat sink, heat sink mounting
frame and PA).  You will be lifting this out as an
assembly.  Do not take out the screws on top of
the heat sink.

5)                 Locate and remove 2 screws in
the In the middle of the radio on 2 tabs that are
also part of the heat sink mounting frame.  Again
do not take out the screws on top of the heat
sink.

6)                 Gently lift out and fold to the
right the heat sink assembly.  Remove the tape
from the wire harness under this assembly.  Place
a folded towel on top of the Top Access Panel
level control board.  You should have just barely
enough slack to lay the heat sink assembly on the
towel.

7)                 Now would be a good time to
take a digital picture of the top of the RF unit
as reference for later re-assembly.  At the very
least note the 2 RF connectors in the back of the
board.  They are close in color and could be
confusing in not careful noting which goes where.
One has its brown band close to the connector the
other tan band is away from the connector.

8)                 Remove the one ribbon connector
on the back right side of the board (again no
retaining collar).

9)                 Remove the 6 RF connectors in
this board.

10)             Locate the white wire harness just
to the left of the RF board.  Cut the 2 cable ties
(this is necessary to get enough clearance in the
wire harness at the front of the RF board to get
it out.

11)             There is also a black vinyl
covered wire harness retainer just behind the
power supply.  Open it for the same reason as 10.

12)             Just in front of this black vinyl
covered wire harness retainer is the frame of the
power supply.  Move the white wire harness to the
right to clear this frame and give you a little
more clearance.

13)             Remove the metal shield along the
left side and front of the RF board (Not the one
on the RF Board).

14)             While lifting the wire harness
that goes across the front of the RF board, gently
lift the front of the RF board and slide it
towards you as much as the power supply allows
(you need to do this to get the rear panel
connectors clear of the rear of the chassis) and
lift out the board.

15)             Follow the InRad instruction in
locating where to place the capacitor.  I found it
very difficult to locate this spot because none of
the parts are labeled on the bottom and the
diagram is only referencing parts on the bottom of
this board.  Look for the pattern and the distinct
Q1001.  There aren't too many of these with the 2
outside legs on one side and the center leg on the
other.  One thing that helps is the 6 surface
mounted parts in a row as follows:  resistor,
resistor, capacitor, resistor, capacitor,
resistor.  I felt the best place to solder the
added cap was next to C1004.

16)             Reverse your steps to reassemble.
To state the obvious don't forget to put the white
wire harness back under the power supply frame,
also the black vinyl wire harness retainer, put
back the 2 cable ties you removed, the ribbon
cable in the RF board and re-tape the wire harness
to the bottom of the heat sink assembly.



Of course I welcome any comments or corrections to
this as I am prone to typos and this was from
memory.  I was not about to re-disassemble my
radio to get it right.



73,



Art

W2NRA