Honeywell HXMT9 / HXMT9X - Manual (Page 20)

Your main monitor should be connected to the MAIN output.
Up to four auxiliary monitors can be connected to the multiplexer. You
can use these as spot monitors or to view live video while playing tapes
back through the main monitor. The auxiliary monitors should be
connected to the AUX BNC connectors.
Connecting Monitors
There are BNC connectors for the VCRs.
Connecting VCRs
< Figure 3 > Connecting one VCR to the . multiplexer
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