Parts List for Broadcast Warehouse 1 Watt LCD ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Resistors --------- R1, R2, R23 1 k R3, R4 68 k R5, R6 220 k R7, R8, R10, R14, R15 1.2 k R16 180 R17, R28 68 R18, R9 10 R20, R22, R25 470 R21 None R24, R12 12 k R13, R26 220 R27 2.2 VR1 1 k pot Capacitors ---------- C1, C5, C13, C30 0.1 uF C2 39 pF C3, C4, C9 2.2 uF C6, C7, C21 0.01 uF C8, C17, C22 82 pF C10, C11, C12, C20 33 uF C14 4.7 pF C15, C25 27 pF C16, C26 56 pF C18, C23, C24, C28 0.001 uF C19 6800 pF for 75 uS 4700 pF for 50 uS C27 12 pF C29 33 pF C31 None C32 220 pF Misc ---- IC1 MC145170 IC2 PIC16F84 IC3 78L05 IC4 LF351 L1 MC120 075 sheilded variable L2 4:1 transformer L3 0.15 uH L4 2.5 turns air variable L5 3.5 turns air variable T1, T2, T3 MPSH10 T4 2N4427 VD1 BB909 VC 5-65 pF variable X1 8.0 MHz crystal SW1, SW2 PCB push buttons LCD LCD display Features -------- * 1 Watt output minimum * Broadband no-tune design * Constant amplitude response * Out of lock RF power down * Harmonic filter * LCD frequency readout * PTH black oxide PC board * RF ground plane, double sided PC board * Audio (deviation adjust) Specifications -------------- Frequency Range Selectable over 87.5 - 108 MHz Step Size 100 kHz steps Frequency Generation microproesser controlled PLL VCO Frequency Stability Better than +/- 1 kHz max, typ +/- 500 Hz Spurious Emissions Better than -75 dB reference to carrier Harmonic Emissions Better than -60 dB reference to carrier RF Power Output 800 mW min, 1000 mW typ. Power Supply 12-15 volts DC regulated Audio Input Sensitivity 0.775 V RMS (typ) to +/- 75 kHz deviation (adjustable) Signal To Noise Ratio -75 dBu Audio Distortion Better than 0.2% THD Audio Freq Response Flat from 20 Hz to 100 kHz Assembly Instructions --------------------- 1. Empty the contents of the kit and proceed to check all of the components off against the component list. It is a good idea to tick off each component as you go through. When you have double checked all the parts proceed. 2. We always start with the lowest height components first which are resistors, Insert each resistor and solder one at a time taking care to make a good joint and not to short across any other pads/holes. Double check the component is the correct one before soldering. 3. Now insert VD1 (SEE DIAGRAM). Move on next to insert the choke L3 and solder this in also. 4. Now insert IC1 and IC2 (see diagram) 5. Next its time to insert the capacitors C1,2,5,6,7,8,13,14,15,16,17,18,21,22 23,24,25,26,27,28,29,30,31 and 32. These can be inserted any way round, they are not polarized. Now insert the polarized electrolytic capacitors C3,4,9,10,11,12 and 20 MAKING 100% SURE they are soldered in correctly (SEE DIAGRAM). The board has a positive symbol next to the positive hole of polarized capacitor. Insert the negative stripe side away from the positve (+) marking. The last fixed capacitor is C19 (this component may need to be omitted form the unit, see pre-emphasis section overleaf to decide if you need to include it. If you do need to include it, choose the correct value from the component list. 6. Insert and solder T1, T2, T3 then move onto T4. Next, IC3, observing the correct component oriention marked on the board (SEE DIAGRAM) 7. Insert the crystal and the VC trimmer capacitor (next to the crystal), and then the metal canned coil L1, and moulded coils L4 and L5. 8. Wind the toroid core with the supplied twisted enameled wire as shown in the diagram and insert and solder as shown in the diagram. Push the clip on (star shaped) heatsink onto T4. 9. By this stage you should have the main component side of the board fully assembled, before moving onto the parts on the other side of the PCB, check all solder joints and connections. 10. Solder in the switches SW1 and SW2 them VR1 (variable resistor). Then, with the supplied standoff pillars, mount the LCD display above the uderside of the board making sure to line up the 14 way connector above the 14 holes left on the PCB. Take the left over cut-off resistor leads you have and pass them through the holes, soldering on the component side of the PCB and LCD screen side of the display PCB. Power Supply ------------ This unit needs a regulated DC power supply between 12 and 15 volts. The only difference with using 12, 13.8 or 15 volts is the output RF power. You will get slightly more output power running the unit from 13.8 or 15 volts as opposed to 12 volts. The unit needs a power supply that can deliver 500 mA or higher. You can connect the DC supply by either soldering the board on the two pads on the top of the PCB or by soldering the leads through the holes onto the pads on the bottom of the PCB. TAKE CARE TO SOLDER THE POSITIVE LEAD TO THE TERMINAL MARKED +. REVERSE POLARITY OF THE LEADS WILL DAMAGE THE EXCITER. YOU HAVE BEEN WARNED. RF Out ------ Before turning on the unit YOU MUST connect a 50 ohm load to the RF output connections. The two pads supplied are to enable you to connect a length of 50 ohms coaxial cable to a RF socket or amplifier. The smaller pad is for the inner wire of the coax (the core) and the longer pad below the RF out pad is to connect the outer of the coax (the braid). (SEE DIAGRAM) We recommend a dummy load is used when tuning up this unit, or if you do not have access to one, at least have an antenna connected to the output. FAILURE TO HAVE A CORRECT 50 OHM LOAD (dummy load or antenna) ON THE OUTPUT MAY RESULT IN DAMAGE OF THE OUTPUT TRANSISTOR (T4). YOU HAVE BEEN WARNED.