Roanoke Circuit Board Errata

FAR Circuits Display Board

Arnie Molloy W1GDJ reports the following errors on v2.0 of the Roanoke Doppler circuit board by FAR Circuits of Dundee, IL. Items 1, 2, 3, 5, and 6 were corrected on v3.0. All items were corrected on v3.5, which is now being shipped.

1. Pins 6,7,and 8 of U3 are tied to U12-12 instead of ground
2. Incomplete trace from a 5V jumper to U3-16 (first board)
3. Incomplete trace from U2-8 to C19 (second board)
4. Collector of Q1 tied to U5-5 instead of 5V.
5. No ground on U4-4 and bottom R-17 (tied together but going nowhere)
6. C1 stenciled as C10
7. C22 and C25 stencilling reversed

Rick Ching KH7O reported the following problems on a FAR Circuits Roanoke board he purchased at the Dayton Hamvention in the late 1990's.

1. Schematic U2d is U1d on board
2. Schematic U1d is U2d on board
3. U1 trace between P13 & P14 shorted
4. R32 and R30 junction missing 5v, correct by connecting to +5v
5. U3 Capacitor on P1 going nowhere, correct by jumpering to similar cap on U3-2
6. U3 Capacitor P4 jumper to cap on P5
7. U4-1 connect to gnd
8. R9 is 22K, not 22 ohms

In addition, on the Display board, the LED anode ring was missing pads for the 56 ohm resistor.

Please send e-mail to if you have more information on this board.

FAR Circuits Antenna Switch Board

There is a minor marking error, but it's very important. Thanks to Craig Young KA5BOU for finding it and reporting it. The labels for the coaxes to antennas #3 and #4 are reversed. See the photo below. Remember that it's very important for the four antennas to switch in a clockwise rotating sequence 1-2-3-4, such as Right-Front, Right-Rear, Left-Rear, Left-Front.

FAR antenna board

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This page updated 20 March 2007