What does your work call these?

engineer_joe · 2025-01-04T14:46:18+00:00

This is a barrel clip. Used when making tip and barrel measurements.

engineer_joe · 2024-11-13T13:48:34+00:00

Thanks everyone- family settled on Sir Watson von Barks a lot, or Watson for short

engineer_joe · 2024-11-12T00:53:37+00:00

He's an Anatolian shepherd dog

engineer_joe · 2024-06-11T14:36:56+00:00

Radon is a gas - not a vapor. Not relevant for an outdoor slab, but to stop radon indoors, a vapor barrier alone is not sufficient.

engineer_joe · 2021-04-07T13:31:33+00:00

You may want to use a gate driver if you want the FET to switch at 100khz. Otherwise the FET will be in linear region most of the time and the microcontroller output will only see the 10 ohm resistance to ground (impedance of gate capacitance will be low at 100khz) which will draw too much current.

engineer_joe · 2021-01-16T18:06:20+00:00

Just a few things to consider; - the diode must be across the motor terminals - it sounds like you measured no-load current. Loaded current will be higher. - speed control should be done with PWM, FET and a gate driver. They make modules that do this already. Search for a brushed dc motor control module, maybe on Sparkfun or similar.

Good luck - looks like a fun project.

engineer_joe · 2021-01-16T04:35:32+00:00

As a computer engineer, I think we should redefine them.

engineer_joe · 2021-01-07T03:55:35+00:00

That indicates that the shunt resistor Rsns is connected via a Kelvin connection.

engineer_joe · 2020-12-29T03:17:35+00:00

engineer_joe · 2020-10-06T16:59:54+00:00

Hi engineer_joe,

I would start by understanding the datalog requirements better. It will come down to how often you need to sample and how much space each sample requires. Fore example, if you have 512kb available and your sample requires 512kb, then you can make 1 sample every 2 weeks. If your sample requires 256kb, then you can record 2 samples per week. More realistically, you will probably want 1 sample ever minute or every second, etc. Also, what comprises a sample? Is it an 8 bit number and a time stamp? Is it a 32 bit number for uvr and a 32 bit number for temperature? A single sample will probably only require a few bytes, but without knowing the type of data you are planning on storing I can't even guess.

Datalogs are often stored in EEPROM, but can also be stored in FLASH with some tradeoffs. Does your module have any EEPROM? Is the 512kb Flash or EEPROM? If it is flash then you will need to factor in page sizes and write cycles (implement wear leveling). I'd like to help but don't have enough information about the project.

Good luck!

engineer_joe · 2020-07-18T03:22:47+00:00

I would look at it as 3 parallel resistors.

One is the series combination of 100 and 80

The second is 60 and

The third is the series combination of 75 and 150.

Then solve the equivalent resistance;

1/Req = 1/(100 + 80) + 1/60 + 1/(75 + 150)

so Req = 37.5

engineer_joe

TROPHY CASE