AS 5203

Description

In 1976, in the midst of the quartz crisis, AS brought out its last selfwinding caliber series, which included the 12 ligne caliber AS 5203, which features a date display.

The base plate reminds very much of a common ETA caliber, which is not surprising, because only two years later ETA and AS merged.

The gear train consists of the second wheel, third wheel (which drives the minute wheel on the dial side), center seconds wheel and escape wheel in a modern design. However, the wheels show a pretty low degree of finishing and look like cheap stamped parts, to be found in quartz movements.

The mainspring barrel drives the rugged second wheel.

With a beat rate of 21,600 vibrations, the AS 5203 performed more conservatively. The three leg anular balance is of course beared in two Incabloc shock absorber bearings. The effective length of the hairspring is regulated via a simply punched spiral key.

The barrel is open at the top; the skeletonized barrel wheel, which on on top of it, also owns the mainspring barrel core.

The ratchet is even simpler executed. It consists only of a special shaped spring that lies under the barrel wheel. Whether the fragile, punched end of locking spring is really durable, may be doubted.

On the left, you see the moveable bearing of the crown wheel.

Since the AS 5203 does not use a Breguet ratchet for winding, a slipable crown wheel engages or disengages the ratchet wheel, depending on the direction of rotation of the crown.

The shape of the lever is very unusual for AS, since it is a lateral lever, on which forka and pallets stand at a 90° angle. In order to limit the path of the lever, a pin embedded in the base plate engages with the hole of the lever and blocks its way.

The AS 5203 was also available as a pretty flat (only 4.7mm height) windup movement, the caliber AS 5201.

The self-winding mechanism is designed in the form of a module with is attachet with two screws to the wheel train bridge.

The rotor only winds the movement in one direction.

The axle of the oscillating weight is part of the selfwinding module.

On the yet empty side of the dial you can already see the space which the calendar mechanism will take up later.

The setting lever spring is as unusual as the whole movement, and so is the time adjustment: The hands setting wheel is not horizontal brought into position, but engages and disengages vertically.

The complex mechanics of the time adjustment and in comparison plus very simple mechanics of the calendar (a weekday display is already prepared) can be seen here. At 2 o’clock you can also see the quick correction wheel for the date display.

Since the dial must be mounted with a certain distance, there there is a spacer ring that provides the necessary distance and simultaneously stores the date ring.

Unfortunately, this work marks the end of the steeped in history automatic calibers from AS, starting with the “Harwood” constructions in the late 1920s and ceasing production in the 1980s when there was no more room for AS automatic movements in the ETA company network.

The quartz crisis forced AS to save money wherever possible and so the AS 5203 impresses more with its ugliness and its partly very idiosyncratic constructions than the impressive execution that was previously known from AS.

Whether the AS 5203 was a reliable design, or whether it went more in the direction of a disposable movement, will probably never be known, since too few of these movements were in use long enough for that.

Technical data