[HCRA] hidden roof antenna

[Tuc]

Hello all,
   I have decided to hit the masses with this question since I want to put the antenna up in the next 2 weeks or so.It will be used to listen only, untill I can cough up the cash a transciever.
   I live in an apartment with a flat roof and was thinking about puting a wire ant up there. It is 45 ft x 45 ft. 
   Field day has really lit a fire under my butt.
Thanks in advance
Tuc
N1QFT