A late 1980s, early 1990s ETA Swiss Technology watch, Moonphase, Triple date, Chronograph, 24hr with constant sub-second, ETA 7751 movement.

It is uncommon for one of these watches to reach the public. These watches were known to be ETA students final exam pieces from the watchmaking school in Grenchen. As such you can rest assured the watch is functioning well, keeping time to within +6 seconds a day.

The case is well proportioned at 41mm and is chrome plated. There is some pitting to the chrome finish and some brassing consistent with age. The case back is stainless steel.
 
As well as the movement, the main talking point of this watch is the dial. It is a complex and intriguing dial as it’s packed full of features to express the movements mechanical ability.
The dial is a white base tone with three sub-dials. Mounted from the centre are 4 hands, one hour, one minute, one chronograph stop watch and on date pointer. The top sub-dial is a 30 minute counter on the chronograph, whilst it also has the day and month window inside of it. The sub-second at 9 o’clock has a constant sub-second and a 24 hour hand to indicate am or pm. The sub-dial at 6 o’clock is a 12 hour counter and moonphase window. This is all well laid out and creates a classy dial.

The ETA 7751 was introduced in 1986 and is a fantastic movement, being referred to as a “Grande Complication”, showing how impressive it was at the time. It is a 25 jewel, automatic movement.
 
Please see the images as these compliment and aid the description provided below.
 
Dial: 
The dial is original and is in excellent condition. It is a white dial with a matte finish. It is a complicated and intriguing dial due to the number of functions. All aspects of the dial are in great condition and the lume is bright. 
 
Hands: 
The hands are original. They are in good condition with no bending and no corrosion. They are painted back and are of dagger style.
 
Glass: 
The crystal is original and is in very good condition with no obvious marking.
 
Crown: 
The crown appears to be original and is in good condition with only light surface scratches.
 
Pushers:
The pushers are chrome plated and are original. They are in average condition with pitting and brassing to the edges.
 
Case:
The front of the case is chome plated. It is in average condition for it’s age. There is some brassing to the top of the bezel which makes it appear gold. There are some small areas of light brassing on the sides of the case too. This is expected as the chrome finish pits and wears.
 
Caseback:
The case back is stainless steel and is in good condition. It has multiple light surface scratches to the polished finish. It is signed “Mica ETA 7751”.
 
Strap: 
The watch is on a new watch gekota 20mm genuine Italian leather racing style strap.
 
Movement:
The movement is an ETA 7751 Automatic 25 jewel movement. 
 
The service history is unknown, but the movement is in good condition cosmetically and is keeping good time. It has a daily gain of -6 seconds, with an amplitude of 315 degrees and a beat error of 2.5m/s.
 
Technical details:
Hours, minutes, small second
Date indication by hand
Chronograph counters 60 seconds / 30 minutes / 12 hours
Day, month and moon phase display in window,
24 hours hand

Chronograph mechanism with cams, 2 push buttons
1 correction push button
Quick correction of date, month and moon phase
Time setting with stop-second
Self-winding mechanism, unidirectional

Frequency: 28'800 vibrations per hour; 4 Hz
25 jewels
Regulator system ETACHRON
Typical power reserve: 54 hours
 
Case dimensions: 
Case width: 40mm 
Case width with crown: 43mm 
Case length: 40mm 
Case length lug to lug: 48mm 
Case Depth: 13mm 
Lug width: 20mm