Showing posts with label multimeter. Show all posts
Showing posts with label multimeter. Show all posts

Epic solar boat adventurer - Watt meter?

Not so long ago I bought a watt meter online and it arrived as described.

I love it when that happens.

The best part isn't that it actually works, and works as advertised (which IS nice), but it tells me my Epic Solar Boat Adventure might actually work. 

I have 360w of solar, and it turns out my motor draws about that same amount of juice when running flat out. 

Hopefully that means I can cruise for a few hours a day at speed  4 of 5 on a sunny day, and still end the day with a full battery in case of snake bite, internet use, phone use, wanting to shine floodlights into the eyes of the local wildlife in that way that we humans tend to enjoy... whatever.

In all these years, I've never really known how much power my trolling motor uses on full power. My multimeter couldn't handle the amperage my motor draws, so I only knew the values for the first 2 of 5 power settings. 

Today is a happy day.

My trip is going ahead.

This stuff is going to work!


120 Things In 20 Years is a little surprised that the math(s) worked

Making smoked foods - Brining and smoking

It seems that brining is really important.

It's soaking food in a salt water solution.

Gratuitous smoked rib shot from last night
From here on in, it gets a little hazy.

Last night I made a brine of water sugar and salt. I'd tell you the proportions, but I don't know what they are. It started with a half cup of rock salt and a half cup of brown sugar, and around two litres of water. But then I added some more water so I really have no idea.







Luckily, my recipe or lack there of isn't the point of this post.

This is...

Apparently brining initially adds salt to the cells in the food, then when the solution is a bit depleted, a cell might have more salt than the surrounding brine, so it starts to draw in water. From what I've read, it might be worthwhile to figure out when that transition takes place, and remove the brine once the cells have started to turn towards taking on water, and replace it with a flavoured liquid instead of just the brine.

With this in mind, I spent a reasonable amount of time probing my whole chicken in brine with the probes of my multi-meter.

It's been an odd night.

It stands to reason that the changing salt content might change the resistance of the chicken. Resistance measures how conductive something is. I'm pretty sure salt water conducts better than pure water, and less sure that perhaps pure water might not conduct electricity much/at all. Either way, there might be something useful to be gained from sticking probes into chicken.

Wikipedia says this on the subject (on conductivity, not on probing chickens)...

--------------------------------

from...  http://en.wikipedia.org/wiki/Purified_water#Electrical_Conductivity


Electrical Conductivity

Electrical conductivity of ultra-pure water is 5.5 × 10−6 S·m−1 (18 MΩ cm in the reciprocal terms of Electrical Resistivity) and is due only to H+ and OH- ions produced in the water dissociation equilibrium.[7][8] This low conductivity is only achieved, however, in the presence of dissolved monoatomic gases. Completely de-gassed ultra-pure water has conductivity of 1.2 × 10−4 S·m−1, whereas upon equilibration to the atmosphere it is 7.5  × 10−5 S·m−1 due to dissolved CO2 in it.

--------------------------------

I'm not really sure why it says that. I'm guessing it means something to someone, but I think it's roughly agreeing with me.

So...

With this in mind, it might be possible to detect the point at which the food stops taking in salt, and starts taking in moisture.

Currently I'm at the stage in my research where I find it annoyingly difficult to get a good reading. The harder you press the probes, the better chicken conducts. I'm guessing this is just because there's more chicken exposed to the current, because there's more probe exposed to the chicken.

So for my next trick, I'l be concentrating on the brine and it's conductivity because I can completely submerge the probes, and as a result, I might get more consistent readings.

I'm also at two more stages.

One is not being sure what I should be looking for in the readings. ie how what's happening should effect the conductivity of the readings.

And the other is wondering if perhaps I should just have a bit of a lie down, and forget the entire episode.




120 Things in 20 years - Maybe the reason aliens are always probing things is because they are trying to ascertain the correct procedure for brining and smoking everything. Aliens like making smoked foods.

Electronics - Breadboard multimeter adapter

For some time now I've been looking for a convenient way to probe around my breadboard with my multimeter. It can be a little tricky, because the probes are too thick to get into the little holes on the breadboard.


I had a bit of an idea today.

I came up with this...



It's a stereo headphone jack with a long length of header pin (sturdy wire used as a plug) soldered to the legs.

I added some insulation in the form of heatshrink, and...

TaDah!

The 120 Things in 20 years multimeter breadboard adapter.




Popular Posts