Why an FM Band Expander?
FM Band Expanders are used in Japanese import cars, as the radios installed in Japan have a frequency band different to the rest of the world – Japan uses the 76-90Mhz radio range and the international FM band covers 88MHz to 108MHz.
By installing an FM Band Expander, it allows a radio’s frequency to shift up, and allows it to pick up all FM radio stations.
How does it work?
A FM Band Expander works by shifting the frequency of the radio. It increases a radio’s Mhz rating, although the numbers displayed on the radio won’t change.
FM Band Expanders: 14Mhz will shift the frequency by 14 or 28Mhz.
To explain further, a 10Mhz band expander will pick up 91.3FM on 81.3FM and 101.5FM on 81.5FM.
A 12Mhz band expander will pick up 91.3FM on 79.3FM and 101.5FM on 77.55FM.
The larger a bandwidth, the greater ability a car stereo has of picking up all FM stations in a particular area. The second harmonic that is fitted to the Antech band expander allows you to pick up the full bandwidth.
If a user comes across two stations on the same frequency, the remedy is to change the Mhz rating of the FM Band Expander so it adjusts the stations accordingly.
An example of two stations appearing on the same frequency is illustrated In Wellington, New Zealand, where there are radio stations 90FM and 100FM.
If fitting an FM Band Expander into a vehicle in this region, a 10Mhz would not prove useful as it would put both radio stations on 80Mhz.
However, a 12Mhz FM Band Expander would shift 90FM to 78Mhz and 100FM to 76Mhz, giving clear reception for both stations.
Finally the 14Mhz band expander is the most suited banded expander for use in New Zealand market.