From a training manual in 2011 (unless it has changed recently):
FDNY FIREGROUND
HT1 - TAC1
HT2 - CMD1
HT3 - TAC2
BOROUGHS - CMD2/TAC3
QUEENS - HT4 / HT5
BROOKLYN - HT5 / HT8
MANHATTAN - HT6 / HT8
BRONX - HT7 / HT6
ST. ISL. - HT8 / HT4
If needed, the Vehicle Repeater System uses 153.830 (5w) from Incident Command
Post to the vehicle and CMD1 from the vehicle to the portable post radio.