digital equipment corporation · maynard, massachusetts
RK05 Drive Information

The RK05J Disk Drive is a removable media hard drive with a total capacity of 1.6 million 12 bit words.  This was normally used with the PDP-8E type omnibus machines.  It was attached to the computer with the RK8E 3 board set which transferred data using the omnibus data break.   The heads are parked off the disk when the drive is shut down.  The drive has a battery in it so the heads can be parked if the power fails.

RK05 Drive Specifications
Data Transfer Rate 9.7 microsecond per word (102k words/second)
RPM 1500
Average Access Time 70 millisecond
Data Tracks 203
Surfaces 2
Sectors per track 16
Words per sector 256 (4096 per track)
Recording Method Double Frequency NRZ
Density 2200 bpi
Tracks per inch 100
Recording Media Iron oxide  disk, 14 inches in diameter
Operating Environment Maximum: 50 to 110 F
Interchangeable range RK05 & RK05J: 30 F
Relative Humidity: 8 to 80 %
Power 250 VA
Weight 110 pounds
Size 19"x10.5"x26.5"
Cost Drive and controller $7900 and $350 installation from DEC in 1974
  74 Dollars per month for maintenance
Additional drives $5100 and $260 installation
  64 Dollars per month for maintenance
Disk cartridge $99

Documents related to RK05

The following picture links also have descriptions of what is shown in the pictures.

Thumbnail Picture Selector

Current size med. Select picture size for links below   Small  Medium  Large

Front of drive ( 82K)  Bottom of drive (105K)  Top right of drive (115K)  Top left of drive ( 97K)
Disk pack ( 42K)  Top of disk (damaged) ( 59K)  Bottom of disk ( 60K)  Pack case ( 48K)
Front M993B Control Cable Board (109K)  Back M993B ( 97K)  Front M993C Control Cable Board (118K)  Back M993C (102K)

Videos of operation of RK05 drive. How to view The large realvideo files are the best but slow to download. The large MPEG has some artifacts from being recorded with interlaced video from a camcorder and is larger than the realvideo.

Loading pack into RK05.
Realvideo: large (746K) Small not available yet.
MPEG: MPEG not available yet.

View of heads loading.
Realvideo: large (301K)

View of heads seeking.
Realvideo: large (553K)

Feel free to contact me, David Gesswein djg@pdp8online.com with any questions, comments on the web site, or if you have related equipment, documentation, software etc. you are willing to part with.  I am interested in anything PDP-8 related, computers, peripherals used with them, DEC or third party, or documentation. 

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