[vcf-midatlantic] Is there a RTC for a PDP-11?

Ok, this might be a stupid question, but is there an eqivalent of a battery-backed time-of-day clock on the PDP-11? I know that it has a LTC signal on the bus which gives basic timing, and RT-11 has both date and time commands which aren’t retained through power cycles. It reminds me of the early PCs when there was no real TOD clock board. I found an M7952 real time clock board, but that looks more like an interval timer board. I also found the M4002 board but that seems like the same thing. Thanks! Get Outlook for iOS<https://aka.ms/o0ukef>