.model qstd npn is=1.0e-16 br=50 br=0.1 rb=50 rc=10 tf=0.12ns tr=5ns +cje=0.4pf vjc=0.8 mje=0.4 cje=0.5pf vjc=0.8 mjc=0.333 cjs=1pf vaf=50 **astable ckt - a simple astable multivibrator vcc 6 0 5 rc1 6 1 1k rc2 6 2 1k rb1 6 3 30k rb2 5 4 30k c1 1 4 150pf c2 2 3 150pf q1 1 3 0 qstd q2 2 4 0 qstd *.plot tran v(2) v(3) v(4) v(1) *.end