Elecraft KPA100UPKT - Manual

El e c r a f t • www. e l e c r af t . c om • 831-662-8345
E L E C R A F T K P A 1 0 0 U P G R A D E I N S T R U C T I O N S
Revision A, October 21, 2006
Copyright © 2006, Elecraft; All Rights Reserved
Introduction
The K2/100 transceiver 100-watt final output stage (KPA100 board) has undergone several important changes since it was
introduced. If your KPA100 was built according to any version of the Elecraft manual Appendix G, 100-W Stage and RS-323
I/O (K2/100), up through revision C, this kit will upgrade your older KPA100 board with all the changes to date. KPA100s
built according to revision D or later of the manual already incorporate these changes.
If you have not already done so, you must also install the shield upgrade (order KPA100SHDKT). You can install the shield
upgrade after you have completed the modifications described here.
Tools Required
You will need the following tools to install this modification kit:
 Fine-tip temperature-controlled ESD-safe soldering station with 700 to 800F tip (370-430C). Recommend a spade
t i p a ppr ox. 0. 05” ( 1. 3 mm) wi de .Do not use a high-wattage iron or soldering gun since this can damage pads, traces,
or the parts themselves.
 IC-grade solder, small-di ame t e r ( . 031”or smaller, Kester #44 or equivalent).
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DO NOT use acid-core solder, water-soluble flux solder, additional flux or solvents of any kind. Use
of any of these will void your warranty.
 A vacuum desoldering tool such as the Soldapullt® model DS017LS. Soldering braid is also handy for removing
excess solder in some situations. See, Soldering and Desoldering below for more information.
 #2 Phillips screwdriver with a small handle.
 Needle-nose pliers.
 Small-point diagonal cutters. Flush-cutting type is required (Xcelite MS54-5J or equivalent).
 Digital Multimeter (DMM) for voltage checks and confirming resistor values. A DMM with capacitance
measurement capability is desirable, but not required.
 A magnifying glass or visor is often invaluable.
 A conductive wrist strap and anti-static mat are strongly recommended. These items are available at very low cost
from Jameco, Mouser, and other electronics suppliers.
Refer to www.elecraft.com for tool sources and solder recommendations.
Soldering and Desoldering
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Use adequate ventilation when soldering; avoid inhaling smoke or fumes. Always wash your hands after
handling solder, as lead residue is highly toxic.
Removing components from double-sided boards can be difficult, since the holes are plated through to connect with traces on
both sides of the board. A number of suggestions are provided below.
When removing components:
 Don't pull a lead or pin out of a hole unless the solder has been removed, or you are applying heat. Otherwise, you can
literally pull the cylindrical plating out of the plated-through hole that joins the top and bottom traces. I f you’ r e having
difficulty, cut the component leads then remove the clipped lead from the hole. Only one component is reused (C83) and
it is clearly identified in the text.