AR-60 vs. AR-50
(Differences between the two systems)

AR-60 Acoustic Release System:

The acoustic release “full featured” AR-60 system is designed to be as reliable as possible.  It features a link connection that uses a bolt, lock washer, and nut to reliably secure the link connection.  The AR-60-E underwater release unit has no internal connectors to fail (with the one exception of one gold plated socket necessary for changing firmware).  It does not have a motor shaft penetrating the pressure housing and subject to leaking or binding from grit.  It has no mechanical leverage on the outside subject to fouling (biological or man made such as from a stray line).  It uses a triple O-ring seal at the battery access end plug.  It uses a special battery holder for 12 standard AA size cells.  Each cell has a diode across it so that if any one, two, three or even four of the 12 cells fail to maintain contact or otherwise fail the diodes will take over and keep the voltage high enough for operation to continue.

Summary list of strong points for AR-60 system (vs. AR-50 system):

  1. Reliable link connection via nut, bolt, and lock washer.
  2. No connectors (except for gold plated firmware socket).
  3. Highly reliable battery system achieved by use of a diode across each of the 12 AA cells.  Standard alkaline AA cells or lithium Energizer L91 AA cells can be used vs. specialized expensive battery packs which can also be difficult to find.
  4. Likelihood of a housing leak into electronics extremely low via use of a triple O-ring seal at battery access opening.
  5. Superior receiver to the AR-50 system receiver.  However, both work well over the ranges specified.
  6. Handles heavier loads than the AR-50 system (200 lb vs. 80 lb for AR-50-AA).

AR-50 Acoustic Release System:

The lower cost acoustic release AR-50 system is designed for lower cost and quick release link change.  There is a single electrical touch contact at the release link needed for rapid change.  There are no diodes across the individual AA battery cells therefore if any one of the 9 battery AA cells were to fail then the release action might fail.

The AR-50 system does not permit interrogation for slant range or for battery status.  In pinger mode the AR-50-AA release unit puts out only 10 mW verses 1000 mW for the AR-60-E.  Operationally, when replacing the link it is imperative that an O-ring be installed between the new link and the electrical contact, otherwise erosion damage to  the contact could occur.  To help prevent this possible oversight a new O-ring is supplied with each new link and a warning label is located near the link.

Summary list of strong points for AR-50 system (vs. AR-60 system):

  1. AR-50 system is lower cost.
  2. AR-50 system has a quicker change of the release link requiring only 10 to 30 seconds.
  3. AR-50 system has a smaller size and lower weight (2.5 lb in air for AR-50-AA vs. 4.8 lb in air for AR-60-E).