dgriffith

joined 1 year ago
[–] dgriffith@aussie.zone 15 points 5 days ago

You people are underselling yourselves.

A thousand a night, indexed to inflation. First year in advance, and then payment every morning after that, with the condition that if you miss one night, it's all over.

I think the ongoing payment adds a bit of spice to it. Do you set a goal of X dollars and stop then? Will you be ordered by the court to continue wearing it for alimony for your gold digging ex wife that you met in the first year? Will the temptation of easy money for minor suffering slowly drive you insane? Time will tell.

[–] dgriffith@aussie.zone 2 points 6 days ago

Thought process goes like this:

"What's slowing us down, hardware-wise? These lidars are expensive and a pain in the ass. Let's disrupt the status quo and ditch them and just use cameras. People drive around just fine with just stereo vision, after all. It might be hard but once we do it we'll be way ahead of the competition."

[–] dgriffith@aussie.zone 2 points 1 week ago (1 children)

People don't give precise percentages though when surveyed. They might round to typical fractions like 1/4, 1/3, or they might round to 10 or 20 percent.

Nobody is saying "hmm, I estimate that it would be approximately 37 percent".

Of course the wisdom of the crowd does wonders for smoothing those coarse estimates, but still, if the crowd is +/- 10 of the real percentage value, I'd say they're pretty much on the money.

Anyway, Poland, wtf.

[–] dgriffith@aussie.zone 6 points 1 week ago

The depth of the water was about the height of the wheels. Which I'm guessing is past 400mm.

Hm. Better check your diff/transfer case oils just in case before things get expensive. Outlanders don't have high mounted diff breathers so you might have got some water in there.

[–] dgriffith@aussie.zone 10 points 1 week ago (1 children)

"I have no mouth and I must scream" could end up being a plausible way to spend eternity.

[–] dgriffith@aussie.zone 3 points 1 week ago

I was thinking that I would have to switch to bsd.

Finally the year of Hurd on the desktop?

[–] dgriffith@aussie.zone 17 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

Not really, it's just phrased differently to the usual signup pitch, they're putting in a middle ground between full "premium" subscribers (whatever that is) and public access with tracking and ad metrics.

Companies need revenue to operate. They get that revenue from advertising data and selling ad slots, or subscriptions. Whether they actually cease all tracking and ad metrics when you subscribe is something I'd doubt though, and that could be a case for the legal system if they didn't do what they claim.

Personally, this behaviour is the point where I would not consider the site to be valuable enough to bother with.

[–] dgriffith@aussie.zone 78 points 3 weeks ago* (last edited 3 weeks ago) (8 children)

"ChatGPT, write a letter to the community that says I am looking after this issue with untrusted BLOBs and it is of high importance but do not be specific about anything."

[–] dgriffith@aussie.zone 7 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

+++

OK

ATH

NO CARRIER

OK

[–] dgriffith@aussie.zone 14 points 4 weeks ago (2 children)

For reference, temps at cradle mountain are still a few degrees below zero overnight.

Soooo, you know, it's nice to feel connected to nature by going barefoot, but shoes are probably a good idea.

[–] dgriffith@aussie.zone 16 points 4 weeks ago (2 children)

Mainly the issues are about providing ~600 kilowatts for 8 minutes to charge your typical size EV battery.

A row of 5 chargers of that size soaks up 3MW if they're all in use, and that's not something that can be quickly or easily shoehorned into a suburban electricity grid.

It's about 500 houses worth of electricity usage, for comparison. For just 5 fast chargers.

Not to say it's impossible, but infrastructure doesn't come cheap, and so it'll cost quite a bit to cram that 80 percent charge into your car's battery.

[–] dgriffith@aussie.zone 5 points 4 weeks ago

You are flashing the chip directly so apart from inadvertent short circuits and such if it doesn't work you can just keep trying until it does.

As for wire length it all depends on how fast they clock the SPI bus when flashing. You'll probably be able to get away with 20cm or so without difficulty , I've driven SPI displays with that kind of wire length before.

 

I know, upvotes/downvotes mean less compared to That Other Place. But it would be nice if I could set Boost to not show all the spammy spam spam in my communities that have a score below a configurable threshold.

 

I subscribe to a bunch of communities and often there is a cross post with the same title and the same URL link across four or five of them at once. This usually results in a screen or two of the same post repeating for me, and I usually just find the one with the most commentary to check out.

It would be nice just to do that automatically, and shrink to a single line or otherwise "fold in" the other cross posts to the highest commentary post so they don't clog my feed. Maybe a few "related" lines under the body of the post when you go into it, similar to the indication that it's been cross posted.

Thoughts?

 

Hi all,

In an effort to liven up this community, I'll post this project I'm working on.

I'm building a solar hot water controller for my house. The collector is on the roof of a three-storey building, it is linked to a storage tank on the ground floor. A circulating pump passes water from the tank to the collectors and back again when a temperature sensor on the outlet of the collector registers a warm enough temperature.

The current controller does not understand that there is 15 metres of copper piping to pump water through and cycles the circulating pump in short bursts, resulting in the hot water at the collector cooling considerably by the time it reaches the tank (even though the pipes are insulated). The goal of my project is to read the sensor and drive the pump in a way to minimise these heat losses. Basically instead of trying to maintain a consistent collector output temp with slow constant pulsed operation of the pump, I'll first try pumping the entire volume of moderately hot water from the top half of the collector in one go back to the tank and then waiting until the temperature rises again.

I am using an Adafruit PyPortal Titano as the controller, running circuitpython. For I/O I am using a generic ebay PCF8591 board, which provides 4 analog input and a single analog output over an I2C bus. This is inserted into a motherboard that provides pullup resistors for the analog inputs and an optocoupled zero crossing SCR driver + SCR to drive the (thankfully low power) circulating pump. Board design is my own, design is rather critical as mains supply in my country is 240V.

The original sensors are simple NTC thermistors, one at the bottom of the tank, and one at the top of the collector. I have also added 4 other Dallas 1-wire sensors to measure temperatures at the top of tank, ambient, tank inlet and collector pump inlet which is 1/3rd of the way up the tank. I have a duplicate of the onewire sensors already on the hot water tank using a different adafruit board and circuitpython. Their readings are currently uploaded to my own IOT server and I can plot the current system's performance, and I intend to do the same thing with this board.

The current performance is fairly dismal, a very small bump of perhaps 0.5 - 1 deg C in the normally 55 degree C tank temperature around 12pm to 1pm, and this is in Australia in hot spring weather of 28-32 degrees C.(There's some inaccuracy of the tank temperatures, the sensors aren't really bonded to the tank in any meaningful way, so tank temp is probably a little warmer than this. But I'm looking for relative temperature increases anyway)

Right now , the hardware is all together and functional, and is driving a 13W LED downlight as a test, and I can read the onewire temp sensors, read an analog voltage on the PCF8591 board (which will go to the NTC sensors), and I'm pulsing the pump output proportionally from 0-100 percent drive on a 30 second duty cycle, so that a pump drive function can simply say "run the pump at 70 percent" and you'll get 21 seconds on, 9 seconds off. Duty cycle time is adjustable, so I might lower it a bit to 15 or 10 seconds.

The next step is to try it on the circulating pump (which is quite an inductive load, even if it is only 20 watts), and start working on an algorithm that reads the sensors and maximises water temperature back to the tank. There are a few safety features that I'll put in there, such as a "fault mode" to drive the pump at a fixed rate if there is a sensor failure, and a "night cool" mode if the hot water tank is severely over temperature to circulate hot water to the collector at night to cool it. There are the usual overtemp/overpressure relief valves in the system already.

All this is going in a case with a clear hinged cover on the front so I can open it and poke the Titano's touchscreen to do some things.

Right now I am away from home from work, so my replies might be a bit sporadic, but I'll try to get back to any questions soon-ish.

A few photos for your viewing pleasure:

The I/O and mainboard plus a 5V power supply mounted up:

The front of the panel, showing the Pyportal:

Thingsboard display showing readings from the current system:

Mainboard PCB design and construction via EasyEDA:

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