TAD_M-10_频率调制校准手册_1998

ALIGNMENT PROCEDURESThe alignment procedure described here is for the M10 covering 138MHz to 174MHz refer to Fig.1For the location of adjustment.PRELIMINIARIESBefore alignments can be performed,the following functions should be programmed into the memory(Flash ROM)by Dealer Mode programming.CHRX FREQTX FREQRX/TX TONETX PWR01138.005138.00502155.005155.005H03155.005155.005123.0(CTCSS)L04155.005155.005023(DCS)H05173.995173.995HRECEIVERVCO VOLTAGEADJUSTMENT1.Set the channel to CH01 (the channel with the lowest receiver frequency).2.Connect a digital multi Meter (DC range)to TP303 on the main PCB.3.Adjust T1 on the VCO to get 1.2V on the multi meter.4.Change the channel to CH 05 (the channel with the highest receiver frequency)and check that TP303Voltage is less than 7.5V)1st LOCAL FREQENCY ADJUSTMENT1.Set the channel to CH02 (the center frequency of the band)2.Connect a Frequency Counter to TP307 on the main PCB.3.Check that the frequency is MHz+100Hz.(receive frequency-21.4MHz)4.Adjust CV301 inside synthesizer if necessary.RX SENSITIVITY ADJUSTMENTS1.Set the channel to CH02.2.Connect a Signal Generator (1kHz modulation at 60%deviation)with -47dBm output to the antennaconnector and an Oscilloscope to the external speaker jack across an 8 ohms load.3.Adjust T301to give a maximum voltage with the best waveform on the Oscilloscope.NOTE::60%deviation is3.0kHz for a system with 5.0kHz full channel deviation.4.Set the channel to CH01.5.Decrease the output of the Signal Generator and adjust T301.302 and 308 for the best sensitivity.Itshould be better than 0.25uV at -12dB SINAD.6.Change the channel to CH 02 and CH05 to confirm the radio's sensitivity across the band.TRANSMITTERVCO VOLTAGE ADJUSTMENT1.Set the channel to CH01(the channel with the lowest transmitter frequency).2.Connect a digital multi meter (DC range)to TP303 on the Main PCB.3.Activate the PTT(transmit)switch.4.Adjust T2 on the VCO to get 1.2V on the multi meter.5.Change the channel to the highest frequency (CH 05)and check that the voltage is less than 8.5Vwhen the PTT is activated.NOTE:If at any time the radio CH display blinks,this indicates that the PLL is out of band.This may occur if aFrequency out of the set bandwidth is selected or may indicate a fault in the radio.