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FPGA-DSP Board for Narrowband SDR

Part 3: microcontroller board

FPGA-DSP Board for Narrowband SDR
Presented in this installment is a user interface (UI) or front end with display, knobs and buttons to control the FPGA-DSP radio. Based on an 8-bit ATmega128A microcontroller from Microchip the board can replace the Raspberry Pi that we used up to now. An audio amplifier is included too, making it possible to listen to the radio without ear-warming headphones.
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Products
Relevant websites
Extra info, Update
FPGA, DSP, SDR, Radio, Ham Radio, RF, Microcontroller
Level
Expert level
Time
4 hours approx.
Tools
SMD soldering tools, drill press, metal work tools
Cost
£90 / €100 / $110 approx.
Component list
From the Store
160410-1: bare PCB for Microcontroller Board
120061-74: 2×16 alphanumeric display

Component List
Resistors
Default: 1%, 0.1W, 0603
R1 = 100kOhm
R2,R3,R6,R12,R15,R19 = 10kOhm
R4,R5 = 120Ohm
R7 = 15Ohm
R8,R9,R10,R17 = 2.2kOhm
R11,R14,R18 = 1kOhm
R13,R16 = 11kOhm
R20 = 22kOhm
R21 = 0.22Ohm
R22 = 220kOhm
R23 = 47kOhm
P1 = 10kOhm linear potentiometer with solder lugs
P2 = 10kOhm horizontal trimpot
Capacitors
Default: 0603
C1,C2,C3,C4,C7,C8,C14,C24,C25 = 100nF
C5,C6 = 33pF (optional)
C9,C10 = 10nF, 1%, U2J
C11,C12 = 1nF, 1%
C13,C21,C22 = 1nF
C15 = 100nF, 1206
C16 = 10nF
C17,C18,C19 = 1µF
C20 = 220µF, 10V, 6.3mm diameter, 2 or 2.5mm pitch
C23,C26 = 10µF, 35V, D 6.3 mm diameter, 2 or 2.5 mm pitch
Inductors
L1 = 10µH, 250mA, 0.2Ohm, 1210
L2,L3,L4,L5 = ferrite bead, 1kOhm @ 100 MHz, 200mA, 0.6Ohm, 0603
Semiconductors
D1 = PMEG3050EP
LED1 = RGB, 5mm, common cathode
IC1 = ATmega128A-AU, programmed
IC2 = TLV314IDBVT
IC3 = NCP431AVSNT1G
IC4 = MAX9711ETC+
IC5 = LD1085V50, TO-220
K1 = 4-pin SIL pinheader, vertical, 0.1” pitch
K2 = 6-pin (2x3) pinheader, vertical, 0.1” pitch
K3,K4,JP1 = 3-pin SIL pinheader, vertical, 0.1” pitch
K5,K6,K7 = 2-way terminal block 630V, 0.2” pitch
K8 = 5-pin SIL pinheader, vertical, 0.1” pitch
LCD1 = HD44780-compatible, 2x16 character LCD
LS1 = mini speaker, 4W, 4Ohm
S1,S2 = rotary encoder + push-on switch, Alps EC11E183440C
S3,S4,S5 = pushbutton, Multimec RA3FTH9
S6 = toggle switch, DPDT, 28VDC, 5A
X1 = 8MHz quartz crystal, 18pF, 5x3.2 mm (optional)
Miscellaneous
For IC5: Insulating kit, thermal pad TO-220 + bush TO-220
For IC5: M3 screw, nut, 2 pcs. Washer
For JP1: shunt jumper, 0.1” pitch
For K1: 4-way SIL pinheader socket, vertical, 0.1” pitch
For K3,K4,P1: 3-way pinheader socket, vertical, 0.1” pitch
For K8: 5-way SIL pinheader socket, vertical, 0.1” pitch
For LCD1: 16-pin SIL pinheader, vertical, 0.1” pitch
For LS1: 2-pin pinheader, vertical, 0.1” pitch
For LS1: 2-way pinheader socket, vertical, 0.1” pitch
For P1: 3-way pinheader, vertical, 0.1” pitch
For S1,S2,P1: Knob, round, 12mm, shaft 6mm
For S3,S4,S5: Cap, black 19mm, Multimec 1S09-19.0
For S6: 3-way PCB screw terminal block 630V, 0.2” pitch
PCB # 160410-1 from Elektor Store
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