![Dialog Dialog](http://data.manualslib.com/pdf2/47/4630/462971-carrier/images/prodialog_plus_30gk_series_instruction_1_thumb.png)
![Manual Manual](/uploads/1/2/5/6/125695202/835990078.jpg)
Store-and-forward is done by the controller. Say that Station 5 gets an incoming DF1 frame and finds that it is addressed from Station 0 to Station 12. Instead of ignoring the packet like it would have in DF1 Half Duplex, it listens to the packet and stores it internally, making note of the target address, the Transaction Sequence Word value, and the CRC. If the CRC is correct, Station 5 will check its Store-and-Forward table to see if the frame's destination address (Station 12) is in that table. Station 5 then waits a few milliseconds (configurable) and re-transmits the DF1 frame to Station 12, preserving the original source Station # and TNSW and CRC value. Then Station 5 kicks back and listens to the network. If Station 5 hears a reply from Station 12 to Station 0, it will do the same function and re-transmit that frame. If Station 5 hears the same command that it just forwarded (remember, it stored the Transaction Sequence Number so it can tell if it's an old or new command) it will refrain from forwarding it again. That's how multiple repeaters can be used in series. In my experience the hardest thing about DF1 Radiomodem protocol is situations where a remote station can sometimes hear the base station transmitting but most of the time only hears the repeater transmitting. This leads to the remote station transmitting its reply to the base station right about the same time the repeater comes on the air sending the repeated request. Of course, these kind of propagation problems only happen on the coldest, clearest nights.... I've seen a lot of constellations from outside sewage pump stations in the middle of January. There's an elegance to it.
SMC Dialog Plus User Manual Controller Bulletin 150 1 11 21 12 22 13 23 14 24 15 25 16 26 17 27 18 28 19 29 20 30 3 5. Throughout this manual attention statements make you aware of safety considerations. Identifies information that is especially important for successful application and understanding of this product. SMC Dialog Plus, SMB.