RL02 Disk Drive

The RL02 drive uses removable disk packs to provide 10MB of storage; twice as much as its predecessor, the RL01. In order to insert or change the cartridge the drive must be powered up and the top cover opened. Rack-mounted drives are therefore fixed to rails which allow the drive to slide out easily.

The RL02 mounted in a 19" cabinet. The unit can slide out freely on rails.

Drive with covers removed, exposing the spindle on which the removable disk is placed.

On the 11/23+ the drives are connected using a RLV12 controller (M8061) in a daisy-chain fashion. Up to four drives can be connected, the last of which must be fitted with a special terminator plug.

A large ciruit board under the maintenance cover, known as the Drive Logic Module (DLM) provides the interface between the drive and the controller card. According to the manual, there are three revisions of this board, of which this is the latest.

The Drive Logic Module (DLM).

Looking down into the unit reveals the blower motor (left) and head positioner cover (centre).

A wonderfuly simple bit of engineering: If you want to change the drive unit number, there's no need to mess around with jumpers. Simply replace the unit indicator cover with one with the desired number! Legs on the back of the cover push into switches to select the matching drive number.

Jumpers? We don't need no jumpers!

The RL02K-DC data cartidge holds 10MB of data.

Documentation & Links

You can find a great introduction to these drives, their controllers and the disk packs on Henk Gooijen's PDP-11 site , specifically here .

As with most DEC equipment, there's a wealth of documentation to be found on Bitsavers . Find a mirror near you by following the above link, then browse to the /dec/disc/rl01_rl02/ directory.