Rather than worrying about an external antenna, first hook any old
convenient length of wire to the AM terminal and see if you can pick
up the stations you want to pick up. If so, you are done. Your
car radio(both AM and FM)is making do with a a piece of wire (antenna)
that's probably considerably shorter than 5 feet.

Mak Wilson wrote:
I have a relatively new hi fi stereo reciever. I also have regular
(properly grounded) TV Antenna (because I'm too cheap to afford cable).
The reciever has a hookup for an FM Antenna into which I run my
regular TV antenna and it works great for FM radio.

Now, I'd like to pick up AM stations. For some reason there is a
different hookup on the reciever for AM stations. Also, there is an
outgoing ground hookup on the back of the reciever which is supposed to
be just for AM Antenna ground.

I'm curious as to why there are separate antenna hookups for FM and AM,
but mostly I just want to know if I can safely and effectively use my
regular TV antenna for both FM and AM, ignoring the AM ground because I
know the antenna is already properly grounded.

Any help? Thanks.