Referring back to Sunday's post, the new Carrabelle repeater antenna is expected to have about 4 dB less gain than the old one. That's a lot. But how much of a real difference in range will this make? Consult the Egli model. In it, range drops as the fourth root of gain (remember to convert from dB to magnitude), so 4 dB down corresponds to about a 21% drop in range, all else being equal (which it never is, but you have to start somewhere). Here's a map of repeater-to-vehicle range predictions for the two antennas:
Not great, but not a deal-breaker either. That's engineering trade-offs for you. If this one is unacceptable, upgrade your vehicle's antenna. Going from a 1 dBi shorty used in the above modeling to a 5/8ths wave antenna will get you nearly all of this range back.
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