ELECRAFT K2 BUILDER ALERT #20, K1 Builder Alert #5
Wrong connector pin length on RF Board P1

March 24, 2003

K1 kits
shipped between about 12/20/02 and 3/21/03.   All later K1s (S/N 1553+) have the correct connector pin  length.

K2 kits shipped between about 1/14/03 and 3/21/03. All after K2s (S/N 3385+) have the correct connector pin  length.


K1 and K2 kits in this date range may have received a 20-pin, right-angle connector whose pins are slightly too long.  If the connector does have pins which are too long, you'll need to shorten the pins slightly as described below. This can be done either before or after the transceiver is assembled. You DO NOT need a new connector. Trimming the pins is entirely satisfactory and will take only a few minutes.


The connector is designated P1 on both the K1 and K2 RF boards. To determine if your P1 has pins which are too long and take corrective action, follow the steps below.

CAUTION: Please make sure to wear eye protection when trimming the pins on the 20 pin connector. It is quite easy for small pieces of metal to fly away as you are trimming each pin.

1. If your kit is unassembled, locate P1, which can be found in one of the RF board component bags. Use the photo of P1 in the RF Board parts list in Appendix A to identify the P1. Then skip to step 5.

2. If your kit has already been assembled, remove the bottom cover (six screws). Look closely at the point where P1 on the bottom of the RF board mates with J1 on the Front Panel board. If there appears to be a large gap between the two connectors (about 1/16" or 1.5 mm), proceed with step 3. If there's only a small gap--about 1/32" or less (0.8 mm or less)--then no action is required, because the pins must be of the correct length.

3. K2 only: Remove the top cover (six screws), then remove the two screws holding the Control board to the Front Panel board. Also remove the KAF2 module if installed.

4. K1 or K2: Remove the four screws holding the Front Panel assembly to the chassis. Unplug the module. (There's no need to remove the knobs or other front panel hardware.) You should now be able to see the pins of connector P1, near the front-center of the RF board.

5. The normal length of the straight part of the pins of P1 is 2/10", measured from the ends of the pins to where the black plastic body begins. (2/10" is about 13/64" or 5 mm.) The incorrect-length connectors have a straight portion which is 3/10" (about 19/64", or 7.5 mm). If your connector has the wrong pin
length, continue with step 6. Otherwise no action is required.

6. If you're certain that you have a connector with the wrong pin length, you'll need to trim the pins as follows. This can be done with the connector either loose or installed.

A. Using a fine-tip marker, make a mark about 1/16" (1.5 mm) back from the tip of one of P1's outermost pins. (It is not necessary to trim off the entire 1/10" (2.5 mm) excess length because the female connector on the Front Panel board can accommodate some of the excess.)

B. Make a similar mark on the tip of a pin at the other end of P1. 

C. Using a straight-edge aligned with both marks, draw a thin line across all 20 pins.

D. Clip off the indicated amount of each of the 20 pins. Use diagonal or flush-cutters.

NOTE: Small variations in clipped length are OK; this will have NO effect on performance or physical stability of the mated connection.

7. Assembled transceiver only: Reinstall the Front Panel module. Be sure to press the Front Panel board firmly against the RF board along the bottom edge so that the connectors become fully mated.

If you have any problems making this modification please email support@elecraft.com .