IIc booting help, please

[wcbland@pacifier.com (Bill Bland)]

Well, I couldn't resist the temptation so I bought the IIc. I don't
have the correct mouse yet, but I've attached my II GS monitor.
All that I get when I turn it on, though, is a screen of narrow black
and blue vertical stripes. 
I located an Apple II system disk on Apple's FTP. The problem with
that is that it's about 840K, which is too large for any disk that
will function in this IIc.
There's an internal 5.25 drive, and I also have a IIc 5.25 drive. I
can see the external briefly light up, but there's no apparent effort
to access the blank disk in it, nor does the internal drive seem to
access the disk inserted.
I don't know enough about this IIc to determine if it's DOA, but it
sure acts like it.
How do I get it going?
Thanks,

Bill