Elecraft K2ATOBKIT - Manual

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U P G R A D I N G T H E E L E C R A F T K 2 T O R E V I S I O N B
Rev. E, April 29, 2003
In October, 2002, the K2 transceiver was updated to incorporate many modifications that had been recommended by
Elecraft or our customers. Any Revision A K2 (or Revision XC, 1999 Field Test) can be brought up to Revision B by
making the changes listed in Table 1. K2s with serial numbers 3000 and higher already include all of the changes
(except the recent PLL Upgrade, which is also discussed in this document). To determine which revision of the K2 you
have, look at the RF board, near "ELECRAFT" label at the center.
Most of the items needed are supplied with the K2ATOBKT mod kit. Other mod kits and parts must be purchased
separately as indicated in the table; these kits come with their own modification instructions. Step 9 (AF GAIN control
modification) does not require a mod kit, but you'll still need to obtain the associated application note (see page 8).
If your present K2 firmware is older than revision 2.00A, you'll need a firmware upgrade (part # FWK2MCIO)
in addition to any hardware mod kits. New firmware installation and realignment will be done in steps 11 and
12, after all desired hardware changes have been made. This ensures that calibration and test steps will only
have to be performed once.
Table 1. Modification Steps
Modification Steps (do in order) Board(s) Part # Pg.
1. Firmware Revision Check and Parameter Save RF n/a 3
2. PLL Frequency Stability at 7182 kHz RF K2ATOBKT 5
3. Misc. RF Board Changes RF K2ATOBKT 6
4. 15/17 meter and 20/30 meter Band-pass Filters RF K2ATOBKT 7
5. BFO Temperature Stability RF BFOMDKT 7
5A. PLL Upgrade (Temperature compensated reference osc.) RF E850138 7
6. VFO ALC and 10/12 meter Band-pass Filter RF E850093 8
7. Second Crystal Filter Flatness RF XFILMDKT 8
8. First Crystal Filter Grounding RF n/a 8
9. AF GAIN Control Smoothness All three n/a 8
10. Misc. Control Board Changes Control K2ATOBKT 9
11. Firmware Installation Control, RF FWK2MCIO 10
12. Alignment and Test Control, RF n/a 10
13. Speaker Grille Cloth n/a E850089 15
NOTE: Not included are Rev. B board changes that accommodate the K60XV 60 meter adapter (RF board: VCO and
40-m low-pass filter). The K60XV manual describes these changes, which should not be made until the option is
installed. Also not included are minor changes that have no impact on operation or performance (for example, RF
board: R60 bias pot changed to a fixed 100-ohm resistor; Control board: switch S1 changed to a jumper block, P7).