[Scan-DC] Radio Shack Antenna Tuning and Mag Mount Antenna Recommendations

[Andy]

Hi folks,

Can anyone tell me the proper length of the antenna segments on the Radio 
Shack Mag Mount Mobile Scanner Antenna Catalog #: 20-032?   I'd like to 
optimize it for 406-512 MHz UHF and 851-868 MHz.

Also, while on the topic, I'm looking for an outstanding mobile antenna that 
operates optimally in the ranges mentioned above.

I have a temporary set up here at the house where I'm using a 4sq ft. piece 
of sheet metal as a ground plane attached to a wooden fence as my base 
antenna.  Its not the best deal in town, but it suffices, as this is 
basically a temp installation just in case the HOA gets mad at me.

Additionally,  anyone know where to pick up a mag mount cell phone antenna 
like the ones they used to sell at Radio Shack?  These were the ones that 
were tuned to the 850 MHz range and they worked great as a temporary base or 
mobile antenna like the setup I have now.  I can't seem to find them 
anywhere even on EBAY.

Thanks,

Andy