First, to clarify, the Quantar has no built-in A-to-D capability [IMBE VOCODER], hence it isn't possible to directly interface an analog device to a Quantar and pass traffic to digital users.
This requires an additional device known as a DIU [Digital Interface Unit] This device was availabe in a desktop version [DIU] or in a metal housing [DIU3000] intended to mount in a rack enclosure. The inner workings of the DIU and DIU3000 are virtually identical. Once you have a DIU, the rest is easy. The DIU can interface to a repeater controller through either its MRTI [phone patch] port or its console port. The DIU can be programmed to transmit from either of those ports any way you wish - analog only, digital only, or follow the last mode used. The DIU is also equipped with I/O for status and control so that your external controller can be aware of the mode in use and/or the external controller can select what mode to use. Thus you have total flexibility and can make your system work pretty much any way you want it to - limited only by your imagination. You could have one PL on the link switch the Quantar to digital and another switch the station to analog. You could even decode the P25 user ID and set the link or other system conditions based on who the user is. BTW, that phone patch port is very helpful, since the DIU will decode P25 dialing from the radio user and generate DTMF locally. This would normally be used for telephone dialing but can be a great way to send control commands to your repeater controller. ---------------------------------------------------------------- --- In [email protected], James Delancy <ctra...@...> wrote: "While we are on the subject of Quantars .... Anybody do any linking of P25/mixed mode operations back into an analog linked system? If so, how did you control whether it would be analog or digital transmissions from the Quantar (or other P25 capable box) when in received a transmission from the linked network?"
