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Summary of Contents for Wavemach FM-3WM
Page 1
NOTE: PLEASE READ ALL THE INFORMATION IN THIS MANUAL BEFORE OPERATING. Introduction The FM-3WM transmitter is a high performance wideband broadcast transmitter board that can be programmed in 100 KHz steps to transmit on any commercial FM frequency in the 87.5-108 MHz band.
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This could occur if the transmitter is incorrectly programmed to a frequency out of the oscillator tuning range. If this occurs it is a good idea to double-check the dipswitch codes. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
1.6 MHz 800 KHz 11-8=3 400 KHz 200 KHz 3-2=1 100 KHz 1-1=0 Note: Switch 12 is always in the on position. The final result should look like this: 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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12 jumpers. 6 jumpers are installed on the top side of the board and 6 jumpers are installed from the bottom side of the board. Solder all the jumpers and clip their leads. See photos for details. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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You should insert the 5K pot which is RV1 and 12 position dip switch together before soldering them since they are very close together. The 5 watt resistor R38 should be installed around 1/16” above the board. See photos for installation details. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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See photos for details. STEP 5 (Refer to Table 7) Install IC U1 which is the large 28 pin chip. Please see the photo for proper orientation of this chip. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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47 pF cap under trimmer C35 Scrape board in the circle area Appearance after scraping Appearance after cap installed 47 pF cap Other 47 and 10 pF caps 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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D3. After the board is complete you can insert the heat sink onto Q5 but wait till you are finished! See the photos for correct installation of all these parts. Large 7805 regulator Large 7805 regulator Small 78L05 regulator 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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Q1 back view Q1 front view Q5 height above board D1 and D2 D200 LED1 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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L10 is a 3 turn ferrite core and should now be installed. See photos for details. L3A + L3B aligned with drill bit L3A and L3B Side profile of L3A + L3B showing height above board 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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Insert L200, L201 and L202 into the PCB board and slide a 7/64” drill bit into all 3 coils to help align them while soldering. These coils should be above the surface around 1/8”. L200, L201 and L202 alignment L200, L201 and L202 after soldering 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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10 minutes. Also now is a good time to visually inspect your board for possible shorts. After you do this then continue to step 1 below. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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If you level is correctly adjusted you should sound about as loud as other stations. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
DC level on Variactor tuning diodes D1 and D2. D1, D2, L3A and L3B form the VHF tank circuit so it is a good idea to check this area on your board if you still have a problem. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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If using the MAR-6/SM for U4 then R29 is 68 to 220 ohms. If using a Hittite 481 chip for U4 then use 68 ohms for R29 Resistors parts count using the Hittite 481 or MAR6 for U4 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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60 inches not supplied Heat sink For Q5 Black wire 5” Shielded audio wire 10” Red wire 4” LED1 mini coax 50 ohms 8” of RG178 or RG 316 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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24K resistor and the RC network. See the photos below for details on this. This modification is also shown in the pink highlighted area in the schematics. Optional input Pre-emphasis network for a mono input 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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Pre-emphasis network to optimize the sound for mono audio sources. The schematics should also help in the event that your kit does not work. 320 Dixon Rd #302-Toronto-ON-Canada-M9R 1S8 tel# (416) 243-2260 web: http://www.wavemach.com/testing email: fm@fmamplifiers.com...
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Do you have a question about the FM-3WM and is the answer not in the manual?
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