Semiconductors and crystal (except U2 and U3) are available as of this writing from Jameco Electronic Components, 1355 Shoreway Road, Belmont, CA 94002, phone (415) 592-8097. Jameco part numbers are shown in a separate column below. William Frovik NØMNB has reported that U2/U3 are available at Techsonic in Foster City, CA 94404, phone (415) 412-5245. More recently, Chris Stewart KE6MNR reported that Techsonic had U2 but did not have U3. He got both ICs from Atex Electronics in San Antonio, Texas, phone (877) 367-2839.
LABEL DESCRIPTION JAMECO P/N U1 74LS75 48021 U2 AY-3-1015D U3 AY-5-8116 U4 MAX233 106163 U5 CD4024 12853 U6 74LS08 46375 U7, U8 555 27422 C1 1 uF C2 10 uF C3 22 uF R1, R5 1 K R2 12 K R3, R4 470 ohms R6 47 K R7 10K VR1 100 K potentiometer X1 4.9152 MHz crystal 14621 LED1, LED2 Light emitting diode Q1 2N3904 38359 Q2 2N2907 38279 D1 1N4148 J1-3 Jumper blocks All resistors are 1/8 watt
Blank etched circuit boards are available form FAR Circuits, 18N640 Field Court, Dundee, IL 60118 (847) 836-9148. Quoted price is $5.50 each plus $1.50 shipping (up to four boards). Add $3.00 service charge for credit card orders.
Larry WB9SDD built a beta version of this board and reports an error as follows: R7 on the board goes from pin 2 of U8 to ground. It should go from pin 2 of U8 to +5volt source per the schematic. If you order this board, check to see if this error has been corrected, and if not, make the correction with cuts and jumpers. Arnold Molloy W1GDJ notes that jumper designations A through H are not stencilled on the board. See the revised schematic for the corresponding IC pins for each jumper.
The new FAR Circuits board measures 3-3/4 by 3-1/8 inches.
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This page updated 21 May 2003