Take a look at this circuit.Guess what happens when input is in high impedence or tristated............the i/p of not gate(74ls04) actually drives the transistor to saturation.When i/p is tristated there is a voltage of about 1.7 volts at the i/pof the not and this voltage drives transistor to saturation.When we first look at the circuit,we may think that the transistor is in cutoff when i/p point is tristed(high impedence).the not gate works fine when driven by 0 or 1and even the transistor.the problem arises only when i/p is tristaed.what fix could i have if i want the circuit to inistialise with tranistor in cutoff and not to give 1 or tistated.is there some other family of not gates i cold use.