Programmer connectors to radios (jacks for mobile radios are shown as they are plugged intoįig. 1h) which shifts up the logic zero volage.įig. This is due to the voltage divider Rk/R1 (see Fig. Usage of Schmitt trigger (VT3, VT4) with the high logic zero threshold (V-=1.7V) is essential if the input and output buses are linked together. A thorough analysis of radios programming circuits leads to the following programmer schematics.įig. 1h shows how the programmer interacts with the radio's programming input/output. Very often they also include additional diodes / transistors / resistors which help linking together data transmit and receive paths of the radio. These circuits include current-limiting resistors, overvoltage protecting diodes, RF EMI (radio frequency electromagnetic interference) filtering capacitors or RC chains. the circuits between the radio accessory connector or microphone connector and the radio processor. On Fig.1 you can see the inner circuits of various radios, i.e. Progamming circuits for several radio types are shown on Fig.1.įig.
Usually radio FPUs have CMOS input and output levels shifted by protection elements. Programmers perform voltage conversion between RS-232 levels and radio specific levels. Programming cables (programmers) for most types of radios are based on the same principles. A Universal Programming Cable For Radios RUSSIAN VERSION VERSION FRANÇAISE - MAGYAR Programming cable description in Hungarian (by Gyula HA7JCA)