[chbot] Robotics Group meeting, 5 Idris Rd, 630pm, Monday 15 May 2023

[Mark Atherton]

Hello everyone,

Good turnout with 24 attendees, and lots of huddles-of tech-talk. $38 + 
change (in gold, and flat-money) collected and transferred into the 
robotics loose-change jar (for later banking).

All sales from the trading table should go into the brown box on the 
wall, and are directly for the benefit of our host club, Christchurch 
Amateur Radio Club, NZART Branch 05.

Equipment donations are welcome for the trading table, but no CRT based 
product, printers, toner or items that are likely to be a disposal burden.

With thanks on behalf of the group,

Mark Atherton


Mark talked about developments in low cost embedded controller + 
graphical LCD GUIs using such tools as RemoteXY and Squareline Studio. 
Associated ESP32s development modules are around NZ$8 ea. 4” SPI LCDs 
with touch are around NZ$33 ea.

Mark brought in a triple-fuel 19mm carburetor which could be used to on 
a 2.5kVA petrol generator. Main points of interest were the addition of 
a gas injection port in the centre of the Venturi choke using a small 
tube, and an external demand valve that is fed from from 3PSI gas feed 
from an LPG cylinder via a cylinder regulator.

Robin Gilks talked about repairing his LED TV by replacing all of the 
backlights in the product. He replaced a whole TVs worth using OEM 
modules costing NZ$20 landed.

Andrew talked about his home-made, if not unusual Direct Digital 
Synthesis application. Unit used a 20+ year old DDS with phase 
modulation to generate a test signal at 146.0MHz with a 1kHz tone, and 
3kHz deviation.

Volker talked about an incredibly dangerous, unisolated light-chasing 
controller/power supply. He also talked about some email configuration 
and privacy issues, along with some preferred providers he had investigated.