I know that TDA7000 is obsolete nowadays, but we managed to bought somewhere near in our place. We need to construct a FM Receiver, capable of receiving signals up to 5 or more stations, ranging from 88Mhz to 108Mhz.
All of the components were bought (TDA7000, capacitors, resistors) but two of them are hard to find. The most problematic to us is the Varicap (Voltage Variable Capacitance Diode)
We used the circuit diagram here --> http://electronics-diy.com/TDA7000_FM_Receiver.php
However, the only available Varicap here in our place were the ff:
MV104 -(Dual Voltage Variable Capacitance Diode, 37-42pF (range cap))
MV2107 -Nominal Cap 22pF
MV1650 -Nominal Cap 100pF
IF we are going to use MV2107 as a substitute for MV2105 (wherein, the MV2105 has a Capacitance: 2 - 16pF ).. What are we going to do if we want to make that MV2107 suitable for the job? Should we change the Value of the capacitors nearby the varicap? or should we put another capacitor in series/parallel? , modify the coil? or change the value of resistor? in order for us to produce a smooth capacitance increments for tuning.
All of the components were bought (TDA7000, capacitors, resistors) but two of them are hard to find. The most problematic to us is the Varicap (Voltage Variable Capacitance Diode)
We used the circuit diagram here --> http://electronics-diy.com/TDA7000_FM_Receiver.php
However, the only available Varicap here in our place were the ff:
MV104 -(Dual Voltage Variable Capacitance Diode, 37-42pF (range cap))
MV2107 -Nominal Cap 22pF
MV1650 -Nominal Cap 100pF
IF we are going to use MV2107 as a substitute for MV2105 (wherein, the MV2105 has a Capacitance: 2 - 16pF ).. What are we going to do if we want to make that MV2107 suitable for the job? Should we change the Value of the capacitors nearby the varicap? or should we put another capacitor in series/parallel? , modify the coil? or change the value of resistor? in order for us to produce a smooth capacitance increments for tuning.