Digital Tempeh Incubator
Modify manual Tempeh Maker to Digital
February 2026

I simplify the Diagram (removing the EARTH BLOCK)


























My good neighbor help me, making the "house" for the STC 1000
Opening for the unit is 28 mm X 70 mm

























I wire no 1,2,5,6,7 and 8
No 3 and 4 are for the temperature sensor (built in already)

























The FINAL wiring



























I use USB fan as a cooling unit,
(Cooling = Removing the heat)
Ordering from Amazon.com

























Dry Run
RED is for the heating unit (light bulb 20 watts)
WHITE is for the USB fan

The "heat" will be "ON" and stop at 31.5 Celsius
The "cooling" will start at 32.0 Celsius and stop running at 31.5 Celsius






















We are modifying from MANUAL to DIGITAL


























Cutting an opening for the "Cooling fan"



























Light and fan are in place























































The programming:

F1 - The temperature that I need - 31.5 Celsius
F2 - The variance between heating and cooling, 0.5 Celsius
F3 - 0 (this is for compressor)
F4 - Calibration, I set it at 0

The heat will stop at 31.5 Celsius, the fan will be on at 32.0 Celsius

















The heating and cooling units.
Lamp - 20 watts and computer fan


























This is day 2
Soak the soybeans for two hours (1 kg)
Boil then cover overnight
This is the first boil.



























De hull and clean the remaining "skins"


























Second boil - add vinegar 1/4 cup
The vinegar is use to make sure only "tempeh starter" ferment.
Boil to a "boiling point" then add 30 more minutes
























To cool down and dry




























Still 33.4 Celsius - too hot

























Now we add the "tempeh starter"
Rhizopus Oligosporus
For 400 grams add 1/4 tsp of "tempeh starter" and 1 tsp of rice flour,
Mixed this earlier!
























1 kg (1000 grams) of dry soybeans become 1,850 grams boiled soybeans
In this case about 462 grams each























Old fashioned sealer
Our electric sealer went to the graveyard.


























Sitting pretty in the new incubator


























The incubation starts - 2/1/2026 at about 1:00 PM



























Morning of 2/2/2026
The heating is off by now, the tempeh in fermenting and create its own heat.
When the temperature hits 32.0 Celsius, the fan will be on,
removing the heat.


























TEMPEH GORENG - Coming Soon





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