Hoptroff Hotblack Calibre Gravitas

cal. No.11B

Factory Spec. 1 SPY

Thermocompensated: Thermistor

User Adjustable: No (self-calibrating)


This should be one of the most accurate watches on the planet. Not just a thermocompensated watch. Not just an internet-sync'd watch. But a thermocompensated watch that adjusts its own rate in accordance with the data gathered during sync. events.

Problems encountered with this watch, so far:

1. The connexion between the app. and the watch sometimes drops for no apparent reason

2. The app. freezes, crashes or otherwise experiences difficulties fairly frequently

3. The arc of the second hand's sweep is wider than the arc of the marked seconds

4. The sync'd time is roughly two seconds behind the actual time

5. Manual time setting does not appear to be able to set the second hand

6. The hour hand sometimes leaps ahead by about 20 minutes, whilst the watch is sitting in a drawer over night, and has to be manually recalibrated in the morning

7. The fit and finish are cheap, with an awkward, low-cost clasp that is incredibly stiff to open and close

In short, this is the sort of watch I would send back if it weren't for the uniqueness of the addition it makes to my collection. It's like Sinclair's 1975 'black watch' all over again. The time is supposed to be set precisely, via the app. Precise to within a tiny fraction of a second of UST. But no matter what I do, the time is always two seconds behind. The watch is supposed to be accurate to within one second per year, but the way that the passing of seconds is recorded effectively prevents the user from ever knowing the correct time.

UPDATE - As this watch cannot be set to the correct time (via an Android platform), I have returned it.

Parent Company none / unknown
Brand Hoptroff
Model Series Hotblack Calibre Edition
Model Name Hotblack Calibre Gravitas
Model Number unknown
Case Number unknown
Serial Number CB0175
Approx. Date of Manufacture 2015
Calibre (mvt maker) No.11B
Calibre (brand) n/a
Factory SPY 1
TC Appproach Count Adjustment & Thermistor
Frequency (XO 1) 32 kHz
Frequency (XO 2) n/a
Rate Adjustment Self-calibrating
Major Inhibition Period (Seconds) unknown
Minor Inhibition Period (Seconds) unknown
Power Disposable Cell
Cell Number CR2330
Case Back screws at six points
Water Resistance 50m
Features 4-hand, numerals at 12, 3, 6 and 9
  Small seconds at 12 o'clock
  analogue date (perpetual) at 6 o'clock
  web-app. sync. and hand alignment
Timing Results Basic Data  &  Further Details
Images Photos - Large File Sizes!
Documents User manual