A FEW ADDITIONAL NOTES:
There are a few prototype E500m's which support ProVoice DES that got out into the 'wild'. Product Management decided to not sell this configuration. But it did work. It used the Orion's ProVoice daughter board.
In addition to the 'normal' 800 and 900 MHz radios, there are several dozen vhf-highband and uhf prototype models which were built but never sold, that have also escaped into the wild. (I own several of each, and have a 136-153 MHz model on my tractor.)
The E500m is basically an updated Orion. If you turn-on the external RS-485 port on the option cable (via a SC4 file), you can attach a Orion control head or Hand Held Controller to it. This SC4 file was written for a transit project for Siemens for city buses in Honolulu about 15 years ago. The Siemens' transit control heads (w/ data & AVL) talked to the radio via RS-485.
EDACS 500m MODEL NUMBERS (unpublished)
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MODEL............DESCRIPTION...POWER
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KRD 103 143/ 1...136-153 MHz...20w
KRD 103 143/ 2...150-174 MHz...20w
KRD 103 143/ 3...403-440 MHz...20w
KRD 103 143/ 4...440-470 MHz...20w
KRD 103 143/ 5...470-512 MHz...20w
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KRD 103 143/ 6...136-153 MHz...40W
KRD 103 143/ 7...150-174 MHz...40W
KRD 103 143/ 8...403-440 MHz...40W
KRD 103 143/ 9...440-470 MHz...40W
KRD 103 143/10...470-512 MHz...40W
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KRD 103 143/21...806-870 MHz...25W
KRD 103 143/31...896-941 MHz...25W
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