(Solved): BJT Astable Multivibrator Similar to the MOSFET, we can also construct and astable multivibrator us ...

BJT Astable Multivibrator Similar to the MOSFET, we can also construct and astable multivibrator using NPN BJTs as seen in Figure 9. For the circuit in Figure 9, to solve for the oscillation frequency, we would use the same technique we used with the MOSFETs, by solving for the charging period for $\mathrm{Cl}$ and $\mathrm{C}2$. In this case, to determine the period, $\mathrm{T}=1/f$, we need to solve for charge time for each leg of the multivibrator where $T=t_1+t_2?t_1=0.69C_1{R}_{B1}$ and $t_2=$ $0.69{\mathrm{C}}_2{\mathrm{R}}_{\mathrm{B}2}$. Therefore, if ${\mathrm{C}}_1={\mathrm{C}}_2$ and ${\mathrm{R}}_{\mathrm{B}1}={\mathrm{R}}_{\mathrm{B}2}$ then the frequency $f=1/\mathrm{T}=1/\left(1.38{\mathrm{R}}_{\mathrm{B}}\mathrm{C}\right)$. For the circuit in Figure 9, solve for the flashing oscillation frequency for ${\mathrm{R}}_{\mathrm{B}1}={\mathrm{R}}_{\mathrm{B}2}=100\mathrm{k}?$ and ${\mathrm{C}}_1={\mathrm{C}}_2=$ $10?\mathrm{F}$. Repeat your calculations for ${\mathrm{C}}_1={\mathrm{C}}_2=1?\mathrm{F}$.