Gleave and Company Watch Parts, Clock Parts and Tools since 1948

£

Measurement of the rate accuracy, the amplitude and
the beat error of mechanical watches
The Watch Expert III is an economic measuring instrument
ideally suited for testing mechanical watches. The diagram
is displayed noiselessly on the new, illuminated LCD graphic
display. Measured values for rate deviation, amplitude and
beat error are automatically calculated and displayed numerically.
The beat number of all common watches will be automatically
recognised. Appropriate measuring modes are available
for watches with special escapements.
Two novelties: the additional display mode “VARIO” and
the storage of the last 5 screen contents, which are later
callable.

£1695.00



Technical Data
Measurement Possibilities
Rate deviation, amplitude and beat error of mechanical
watches. Diagram of the beat noises.

Beat Error
Automatic selection of all common beat numbers. Manual
selection of less common beat numbers. Manual selection
of any beat number between 3’600 to 43’200 b/ h. Determination
of an unknown beat number.

Measuring Modes
–– Stnd Standard mode for watches with the Swiss
escapement.
–– Spe1 Mode for watches with coaxial escapement.
–– Spe2 Mode for watches with AP escapement.
–– Spe4 Mode with specific amplitude filter.
–– Rate Only the rate measurement occurs.

Gain Control
Automatic. Manual control facility for watches with stray or
unusual beat noises.
Display
–– Cont Continuous diagram recording of the beat noises
and display of the numeric values for the rate accuracy,
amplitude and beat error.
–– Vario Enables to examine the stability and scattering of
the rate accuracy or the amplitude over a long period of
time (max. 100 hours). Graphic-linear display with a
measuring range of ± 50 s/d, ± 10 s/d for the rate accuracy
and from 120° to 320° for the amplitude. Numerical
display for the actual rate, amplitude and beat error.
Indicated are also the minimum and the maximum rate
deviation as well as the average values of the rate since
measuring start.
Rate accuracy: numerical display in s/d. Resolution:
1 s / d with a measuring range of ± 999 s / d or
0.1 s / d with a measuring range of ± 99.9 s / d.
Amplitude: numerical display in degrees.
Resolution 1°. Measuring range from 70° to 360°.
Lift angle adjustable from 10° to 90°.
Beat error: numerical display in milliseconds.
Resolution 0.1 ms. Measuring range 9.9 ms.
Diagram recording on an illuminated LCD graphic display
with 256 x 64 dots.
Time scale adjustable from 1 up to 9 mm / ms (zoom).
4 selectable tracing speeds.
In the measuring mode Cont (diagram recording) the last
five screen contents are callable.
Recording speed: depends on the beat number, 0.56 mm
per watch beat. Visible diagram length: 143 mm.

Functions
Selectable measuring time for numerical results: 2, 4, 8, 10,
20, 30, 60 s and automatic selection of the shortest possible
measuring time. Continuous renewal of the average values
every 2 s over the measurement period. Display on the
screen of the evaluated part of the rate measurement diagram.
Start / stop: enables to stop the current screen display and
to re-start the measurement.
Acoustic check: built in loudspeaker to hear the beat
noises.
RS232-interface for the connection of the Witschi thermoprinter,
of a PC or the Witschi GPS receiver. Print out of the
numeric results or graphic print out of the displayed diagram.

Details
Time base: high frequency quartz time base, XO.
Stability : + / – 0.08 s / d between 20° and 40° C.
Aging for the first year: + / – 0.03 s / d.
Plastic housing, light grey.
Dimensions: 250 x 135 x 101 mm (w x h x d).
Weight: 2,1 kg, microphone included.
Mains connection: mains adapter for 230 V~ or 120 V~,
1.2 A.
Power consumption: 4.7 W, stand by 3.2 W.
Stand microphone movable for any test position, suitable for
watch movements and watches with or without bracelet.

Accessories
Clamping microphone for wall clocks. Item 13.1820
Optoelectronic sensor for pendulum clocks. Item 13.1620
Tripod for optoelectronic sensor. Item 13.16.201
Thermo printer Witschi with Item JB01-MCP7810
graphic mode, universal mains adapter
90 V~ - 260 V~, cable and 1 paper roll.
Thermo paper, roll. Item JB01-MM58-DPU20-N
Autoprint: PC software for result Item 64.55.901PK1
and graphic file transmission
to a PC.
Witschi GPS receiver. Item 19.91PK1 (230 V~)
19.91PK1 (120 V~)