might be dependent on where I parked the car
The Natural Philosopher wrote:
might be dependent on where I parked the car
Monitoring within the appliance bays of multiple fire stations,
certainly shows signal levels exhibiting high and low levels depending whether the truck is in or out ...
On 09/12/2025 11:57, Andy Burns wrote:
The Natural Philosopher wrote:Umm. Well now the rain has gone and the wind died down a little I am
might be dependent on where I parked the car
Monitoring within the appliance bays of multiple fire stations,
certainly shows signal levels exhibiting high and low levels depending
whether the truck is in or out ...
getting +6dB better signal. I could move the car...
I'll park that one (sic") till I use the car again, then I'll move it ...
In comp.os.linux.misc The Natural Philosopher <tnp@invalid.invalid> wrote:
On 09/12/2025 11:57, Andy Burns wrote:
The Natural Philosopher wrote:Umm. Well now the rain has gone and the wind died down a little I am
might be dependent on where I parked the car
Monitoring within the appliance bays of multiple fire stations,
certainly shows signal levels exhibiting high and low levels depending
whether the truck is in or out ...
getting +6dB better signal. I could move the car...
I'll park that one (sic") till I use the car again, then I'll move it ...
Water greatly absorbs 2.4Ghz signals, so it is not surprising you see stronger signals once the extra "water" is no longer in the signal
path.
The Natural Philosopher wrote:
might be dependent on where I parked the car
Monitoring within the appliance bays of multiple fire stations,
certainly shows signal levels exhibiting high and low levels depending whether the truck is in or out ...
If monitoring 'emergency vehicles/installations'
is critical, maybe consider something using lower
frequencies than wi-fi ???
c186282 wrote:
If monitoring 'emergency vehicles/installations'
is critical, maybe consider something using lower
frequencies than wi-fi ???
Nah, it was mostly "for interest" to gather a few more values from kit that's already being monitored. Someone else mentioned water (presumably
as rain) don't forget the fire appliances carry around their own water,
but hopefully it's low down for CoG reasons, while the access points are mounted higher up.
Now if real, legal, 'security' was an issue
then you'd want a solid connection all of
the time ... and one wi-fi point likely won't
provide that.
c186282 wrote:
Now if real, legal, 'security' was an issue
then you'd want a solid connection all of
the time ... and one wi-fi point likely won't
provide that.
Only the largest couple of stations have multiple APs in the bay. The building and individual vehicles have 4G, and the buildings form a
meshed POCSAG network between neighbouring towns (or parts of cities).
an 'extender' is a bit different from
an 'access point' (and cheaper). The extender
binds to the access point/router. Connected
devices may, as needed, connect to the main
point or the address of the extender and still
get net access.
judging by the problem you claimed, your
easy fix is an extender.
c186282 wrote:
judging by the problem you claimed, your
easy fix is an extender.
I didn't say there was a problem, just that you can notice signal levels
go up and down depending on the presence or absence of a big red truck.
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
If monitoring 'emergency vehicles/installations'
is critical, maybe consider something using lower
frequencies than wi-fi ??? In USA I think there's
a designated comm space in the 400mhz band. It'd
still be good enough for a 1-fps camera feed.
Ah ... POTENTIAL cheap solution. Haven't fooled
with it in about 10 years but I think it's still
possible with Linux. Just buy one of those wi-fi
extender/repeater thingies (about $50 USD) and
put it not far from the main router. Make it
wlan1. At least with wpasupplicant and dhcpcd.conf
you could designate an automatic "fall over" in
case the main signal got crappy. Not 100% sure
what happens now with apps if you list a wlan0 and
wlan1 at the same time - will the app just use
whichever, or both, without complaints ???
Between the two, 'shadow' areas ought to largely
go away.
Pity nobody makes a 5ghz "viewer" so you can
get at least a fuzzy picture of the signal at
different places 🙂
I have a repeater to reach an out-building. Gonna--
try to add it as wlan1 just to see what happens ...
Easiest ... add one wifi extender, log into
the camera, see whether you get more bars
with the main or the extender.
c186282 wrote:
judging by the problem you claimed, your
easy fix is an extender.
I didn't say there was a problem, just that you can notice signal levels
go up and down depending on the presence or absence of a big red truck.
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
On 12/10/25 04:14, Andy Burns wrote:
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
Posting traffic has considerably increased of late,
partly my "fault" ... but COSLM was kind of dying
and that would have been tragic. Forgive the sort
of off-topic stuff, but it DOES keep minds alive -
you can't ALWAYS think about Linux without kind
of seizing up :-)
On 10/12/2025 02:19, c186282 wrote:
If monitoring 'emergency vehicles/installations'465Mhz.
is critical, maybe consider something using lower
frequencies than wi-fi ??? In USA I think there's
a designated comm space in the 400mhz band. It'd
still be good enough for a 1-fps camera feed.
Its equally shit really.
I ought to resurrect 27MHz.. that is still free-ish
Ah ... POTENTIAL cheap solution. Haven't fooledDepends how they are set up.
with it in about 10 years but I think it's still
possible with Linux. Just buy one of those wi-fi
extender/repeater thingies (about $50 USD) and
put it not far from the main router. Make it
wlan1. At least with wpasupplicant and dhcpcd.conf
you could designate an automatic "fall over" in
case the main signal got crappy. Not 100% sure
what happens now with apps if you list a wlan0 and
wlan1 at the same time - will the app just use
whichever, or both, without complaints ???
Between the two, 'shadow' areas ought to largelyWell they do. Its called a smart phone.
go away.
Pity nobody makes a 5ghz "viewer" so you can
get at least a fuzzy picture of the signal at
different places 🙂
If te phone has 5Ghz wifi then a wifi sniffer app shows all.
I have a repeater to reach an out-building. Gonna
try to add it as wlan1 just to see what happens ...
On 10/12/2025 05:27, c186282 wrote:
nastiness.
Easiest ... add one wifi extender, log into
the camera, see whether you get more bars
with the main or the extender.
Actually something that might be of interest...
# iwlist wlan0 scanning | grep -e Cell -e Channel -e Quality -e Encrypt
-e ESSID
Shows all stations visible to a ZeroW ... run it as root...
Cell 01 - Address: 00:1D:AA:79:78:40
Channel:7
Frequency:2.442 GHz (Channel 7)
Quality=44/70 Signal level=-66 dBm
Encryption key:on
ESSID:"Wifi1"
Cell 02 - Address: 30:46:9A:A2:89:F6
Channel:13
Frequency:2.472 GHz (Channel 13)
Quality=51/70 Signal level=-59 dBm
Encryption key:on
ESSID:"wifi2"
Cell 03 - Address: 74:4D:28:4A:21:86
Channel:3
Frequency:2.422 GHz (Channel 3)
Quality=35/70 Signal level=-75 dBm
Encryption key:on
ESSID:"wifi3"
etc etc.
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:I stated for te record and for the interest of others doing outside wifi coupled IOT shit that rain wind and possibly cars made a difference.
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
Posting traffic has considerably increased of late,
partly my "fault" ... but COSLM was kind of dying
and that would have been tragic. Forgive the sort
of off-topic stuff, but it DOES keep minds alive -
you can't ALWAYS think about Linux without kind
of seizing up :-)
Someone else remarked that so did fire trucks.
The downside of the new oil monitor is that is is so accurate - to
within a litre it seems - that I can visibly see how much a shower or washing the dishes costs me, and a cold night is very expensive. :-)
LOL.
Now off to write the software that will look at it for me and warn me of things by email.
So I can get on with the next project.
On 12/10/25 04:47, The Natural Philosopher wrote:
I ought to resurrect 27MHz.. that is still free-ish
It can be good for some stuff, alas not IP
cams and other higher-bandwidth devices.
Hmmm ... maybe 300 Hz ? Goes everywhere !
Pity nobody makes a 5ghz "viewer" so you canWell they do. Its called a smart phone.
get at least a fuzzy picture of the signal at
different places 🙂
"Bars" ??? How CRUDE ! :-)
I wanna SEE colors on the walls.
DID add a wlan1 ... but, as was, not really useful.
You could connect to one, or the other, but there's
no inherent fail-over. Apparently there IS some
software, and/or evil config/iptables, fixes ...
but kinda icky.
What we WANT is for a device connection to use
the BEST signal - whether that's the primary
router or an extender - and switch back and
forth automatically depending on the connection
quality. Looks like it CAN be done ... but ....
On 12/10/25 04:55, The Natural Philosopher wrote:
On 10/12/2025 05:27, c186282 wrote:
nastiness.
Easiest ... add one wifi extender, log into
the camera, see whether you get more bars
with the main or the extender.
Actually something that might be of interest...
# iwlist wlan0 scanning | grep -e Cell -e Channel -e Quality -e
Encrypt -e ESSID
Shows all stations visible to a ZeroW ... run it as root...
Cell 01 - Address: 00:1D:AA:79:78:40
Channel:7
Frequency:2.442 GHz (Channel 7)
Quality=44/70 Signal level=-66 dBm
Encryption key:on
ESSID:"Wifi1"
Cell 02 - Address: 30:46:9A:A2:89:F6
Channel:13
Frequency:2.472 GHz (Channel 13)
Quality=51/70 Signal level=-59 dBm
Encryption key:on
ESSID:"wifi2"
Cell 03 - Address: 74:4D:28:4A:21:86
Channel:3
Frequency:2.422 GHz (Channel 3)
Quality=35/70 Signal level=-75 dBm
Encryption key:on
ESSID:"wifi3"
etc etc.
Interesting.
DOES show a number of "cells" ... but not the ESSID of
my extender for some reason.
In theory, this sort of data could be used by a
relatively simple daemon to switch back and
forth to the 'best' signal. The old CL stuff
is fine ... but can sometimes be replaced by
half a dozen lines of more-comprehensible Python.
On 12/10/25 05:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:I stated for te record and for the interest of others doing outside
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
Posting traffic has considerably increased of late,
partly my "fault" ... but COSLM was kind of dying
and that would have been tragic. Forgive the sort
of off-topic stuff, but it DOES keep minds alive -
you can't ALWAYS think about Linux without kind
of seizing up :-)
wifi coupled IOT shit that rain wind and possibly cars made a difference.
Someone else remarked that so did fire trucks.
The downside of the new oil monitor is that is is so accurate - to
within a litre it seems - that I can visibly see how much a shower or
washing the dishes costs me, and a cold night is very expensive. :-)
LOL.
Now off to write the software that will look at it for me and warn me
of things by email.
So I can get on with the next project.
Somebody said something interesting ... that
the effect of the Big Red Truck on the wifi
signal kind of turned it into a radio proximity
sensor. Ya know, THAT might be useful ......
As for The Project ... with enough interesting
input The Project might change ... to something
More Interesting :-)
Hmmm ... My stuff gives off wifi, and there are a
few neighbors too. MIGHT be I could sample signal
strength and come up with certain 'fingerprints' -
like of vehicles driving by or, more important,
the Amazon truck pulling into my driveway ...
BEEP !!!
See how little stuff can spawn bigger ideas ? :-)
What we WANT is for a device connection to use
the BEST signal - whether that's the primary
router or an extender - and switch back and
forth automatically depending on the connection
quality. Looks like it CAN be done ... but ....
On 10/12/2025 10:29, c186282 wrote:
What we WANT is for a device connection to use
the BEST signal - whether that's the primary
router or an extender - and switch back and
forth automatically depending on the connection
quality. Looks like it CAN be done ... but ....
I have a bunch of Ubiquity UbiFi access points around the house with
wired backhaul to the router. They can also work with wireless backhaul,
but we were having the house rewired so putting a load of CAT6 in, and a
POE switch, was a no-brainer.
They do exactly that. As a device moves between areas with different APs
the APs detect which has the best signal and the one with the lower
signal strength drops the connection. The device then reconnects and
picks the one with the stronger signal.
They've been in place about four years, now, and seem to work well.
On 10/12/2025 10:29, c186282 wrote:
What we WANT is for a device connection to use
the BEST signal - whether that's the primary
router or an extender - and switch back and
forth automatically depending on the connection
quality. Looks like it CAN be done ... but ....
I have a bunch of Ubiquity UbiFi access points around the house with
wired backhaul to the router. They can also work with wireless backhaul,
but we were having the house rewired so putting a load of CAT6 in, and a
POE switch, was a no-brainer.
They do exactly that. As a device moves between areas with different APs
the APs detect which has the best signal and the one with the lower
signal strength drops the connection. The device then reconnects and
picks the one with the stronger signal.
They've been in place about four years, now, and seem to work well.
On 10/12/2025 13:01, Daniel James wrote:
On 10/12/2025 10:29, c186282 wrote:Aha. So that's how they do it. No intelligence required in the client
What we WANT is for a device connection to use
the BEST signal - whether that's the primary
router or an extender - and switch back and
forth automatically depending on the connection
quality. Looks like it CAN be done ... but ....
I have a bunch of Ubiquity UbiFi access points around the house with
wired backhaul to the router. They can also work with wireless
backhaul, but we were having the house rewired so putting a load of
CAT6 in, and a POE switch, was a no-brainer.
They do exactly that. As a device moves between areas with different
APs the APs detect which has the best signal and the one with the
lower signal strength drops the connection. The device then reconnects
and picks the one with the stronger signal.
So they talk to each other 'my client needs to be your client.'
That only happens with me when they go out of range completely.
They've been in place about four years, now, and seem to work well.
Everybody thoughtReminds me of a brand new factory in Jo'burg. Solid concrete walls and a
that the 1950s were the pinnacle of modern civ ...
"What else WOULD you need to add in ???".
On 11/12/2025 04:12, c186282 wrote:
Everybody thoughtReminds me of a brand new factory in Jo'burg. Solid concrete walls and a
that the 1950s were the pinnacle of modern civ ...
"What else WOULD you need to add in ???".
tin roof. And nnot a single socket or light that worked.
The contractor brought in to fix it spent 20 minutes looking and then
said 'Fuck that - get the Kangas' and simply chipped new channels for *everything*. Laid in pipe conduit and got wiring.
Before the days of computers that was, let alone networking. We used Telex.
The contractor brought in to fix it spent 20 minutes looking and then
said 'Fuck that - get the Kangas' and simply chipped new channels for *everything*. Laid in pipe conduit and got wiring.
... they just run lots of pipes on the outsides of the thick stone
walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
On 11/12/2025 04:12, c186282 wrote:
... they just run lots of pipes on the outsides of the thick stone
walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
Have you SEEN the Centre Georges Pompidou in Paris?
... or the Lloyds Insurance building in London, for that matter.
On 2025-12-11, Daniel James <daniel@me.invalid> wrote:
On 11/12/2025 04:12, c186282 wrote:
... they just run lots of pipes on the outsides of the thick stone
walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
Have you SEEN the Centre Georges Pompidou in Paris?
... or the Lloyds Insurance building in London, for that matter.
I seem to remember hearing that there was an English building code that REQUIRED outside pipes for water (and sewage?) so that they could be
easily thawed with a blowtorch when they froze in the winter?
On 11/12/2025 18:16, Lars Poulsen wrote:
On 2025-12-11, Daniel James <daniel@me.invalid> wrote:
On 11/12/2025 04:12, c186282 wrote:
... they just run lots of pipes on the outsides of the thick stone
walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
Have you SEEN the Centre Georges Pompidou in Paris?
... or the Lloyds Insurance building in London, for that matter.
I seem to remember hearing that there was an English building code that
REQUIRED outside pipes for water (and sewage?) so that they could be
easily thawed with a blowtorch when they froze in the winter?
No, it was only done to save money.
I've had to skip subject threading because of all
the new postings ... just datetime sorting now.
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:I stated for te record and for the interest of others doing outside wifi coupled IOT shit that rain wind and possibly cars made a difference.
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
Posting traffic has considerably increased of late,
partly my "fault" ... but COSLM was kind of dying
and that would have been tragic. Forgive the sort
of off-topic stuff, but it DOES keep minds alive -
you can't ALWAYS think about Linux without kind
of seizing up :-)
Someone else remarked that so did fire trucks.
The downside of the new oil monitor is that is is so accurate - to
within a litre it seems - that I can visibly see how much a shower or washing the dishes costs me, and a cold night is very expensive. :-)
LOL.
Now off to write the software that will look at it for me and warn me of things by email.
So I can get on with the next project.
First of all thanks to all those who responded on my first efforts to
put a battery power Pi Pico W outside and have it phone home.
Having eliminated temperature and supply voltage as issues, I delved
into wifi and router logs, and it was clear that it was sometimes
getting a DHCP lease and even occasionally opening a TCP/IP connections
and sending data. And might be dependent on where I parked the car and
the weather.
I tried putting a tin tray behind the router and that made it worse.
Now the layout was that a ground floor router through the window and the garage was not very good at about 30m range.
Then I remembered I had put an Ethernet port in an upstairs bedroom by
the window in case I wanted to use it as an office.
It was further away - 35m or so - but much less cluttered path. It just
had to go through a corner of the garage.
Instantly the router reported about 8-10dB more signal and almost
reliable comms resulted.
And I knew all that trig would come in handy one day :-)
On 2025-12-10 11:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:I stated for te record and for the interest of others doing outside
c186282 wrote:
I think it was you ... said how a cam wouldNo, maybe TNP said his oil level monitor would drop out?
more or less drop out when the Big Red Truck
was there.
Posting traffic has considerably increased of late,
partly my "fault" ... but COSLM was kind of dying
and that would have been tragic. Forgive the sort
of off-topic stuff, but it DOES keep minds alive -
you can't ALWAYS think about Linux without kind
of seizing up :-)
wifi coupled IOT shit that rain wind and possibly cars made a difference.
Someone else remarked that so did fire trucks.
The downside of the new oil monitor is that is is so accurate - to
within a litre it seems - that I can visibly see how much a shower or
washing the dishes costs me, and a cold night is very expensive. :-)
LOL.
Now off to write the software that will look at it for me and warn me
of things by email.
So I can get on with the next project.
You mentioned thieves stealing fuel. You can also monitor for that. You would need a fuel flow meter on the fuel line, or a sensor telling when
the furnace is working. Compare with the tank level decreasing rapidly.
the sensor I built on the tank has no power except batteries: So it only wakes up occasionally and draws nanoamps in between.
I have completed the warning software that looks for low oil levels,
loss of communication, a failing battery and unexpected changes in oil level, BUT it cannot do that in real time as the unit is only powered up
for a minute or so every couple of hours.
Depending on how long the batteries last I may increase the frequency of operation.
On 2025-12-09 11:47, The Natural Philosopher wrote:
First of all thanks to all those who responded on my first efforts to
put a battery power Pi Pico W outside and have it phone home.
Having eliminated temperature and supply voltage as issues, I delved
into wifi and router logs, and it was clear that it was sometimes
getting a DHCP lease and even occasionally opening a TCP/IP
connections and sending data. And might be dependent on where I parked
the car and the weather.
I tried putting a tin tray behind the router and that made it worse.
Now the layout was that a ground floor router through the window and
the garage was not very good at about 30m range.
Then I remembered I had put an Ethernet port in an upstairs bedroom by
the window in case I wanted to use it as an office.
It was further away - 35m or so - but much less cluttered path. It
just had to go through a corner of the garage.
Instantly the router reported about 8-10dB more signal and almost
reliable comms resulted.
Two ideas.
Some routers can steer the signal horizontally; the technology is called "MIMO" (https://en.wikipedia.org/wiki/MIMO). You notice because the
router has multiple antenas, maybe four.
Then you can replace the antena on the router or the remote with a directional WiFi antena. Home made with a box of Pringles. just google
for "pringles wifi antenna". I made one and it actually works. But maybe they are sold, too.
...
And I knew all that trig would come in handy one day :-)
You can calculate it numerically on a computer, by calculating the aproximate integral ;-)
The Natural Philosopher wrote:
the sensor I built on the tank has no power except batteries: So it
only wakes up occasionally and draws nanoamps in between.
I have completed the warning software that looks for low oil levels,
loss of communication, a failing battery and unexpected changes in oil
level, BUT it cannot do that in real time as the unit is only powered
up for a minute or so every couple of hours.
Depending on how long the batteries last I may increase the frequency
of operation.
Worth trying to send the data as UDP rather than TCP? if it fits in a
single packet,the receiver doesn't have to track the position within a stream ...
On 2025-12-11 19:28, John R Walliker wrote:
On 11/12/2025 18:16, Lars Poulsen wrote:
On 2025-12-11, Daniel James <daniel@me.invalid> wrote:
On 11/12/2025 04:12, c186282 wrote:
... they just run lots of pipes on the outsides of the thick stone
walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
Have you SEEN the Centre Georges Pompidou in Paris?
... or the Lloyds Insurance building in London, for that matter.
I seem to remember hearing that there was an English building code that
REQUIRED outside pipes for water (and sewage?) so that they could be
easily thawed with a blowtorch when they froze in the winter?
No, it was only done to save money.
It seems amazing to me doing that in Britain, were pipes can freeze. Now
I understand the description of an hotel (Devon) in a novel I'm reading (Ruth Rendell, The secret house of death).
On 11/12/2025 21:06, Carlos E.R. wrote:
On 2025-12-10 11:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:
c186282 wrote:
Now off to write the software that will look at it for me and warn me
of things by email.
So I can get on with the next project.
You mentioned thieves stealing fuel. You can also monitor for that.
You would need a fuel flow meter on the fuel line, or a sensor telling
when the furnace is working. Compare with the tank level decreasing
rapidly.
The problem is that the sensor I built on the tank has no power except batteries: So it only wakes up occasionally and draws nanoamps in between.
I have completed the warning software that looks for low oil levels,
loss of communication, a failing battery and unexpected changes in oil level, BUT it cannot do that in real time as the unit is only powered up
for a minute or so every couple of hours.
Depending on how long the batteries last I may increase the frequency of operation. But it can never be 'real time'
Two ideas.
Some routers can steer the signal horizontally; the technology is called "MIMO" (https://en.wikipedia.org/wiki/MIMO). You notice because the
router has multiple antenas, maybe four.
Then you can replace the antena on the router
directional WiFi antena.
Home made with a box of Pringles. just google
for "pringles wifi antenna". I made one and it actually works. But maybe they are sold, too.
Well the daemon runs under xinetd...for sheer laziness. I guess I could
make it UDP.
But I don't know what problem that would solve.
On 2025-12-12 11:26, The Natural Philosopher wrote:
On 11/12/2025 21:06, Carlos E.R. wrote:
On 2025-12-10 11:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:
c186282 wrote:
Now off to write the software that will look at it for me and warn
me of things by email.
So I can get on with the next project.
You mentioned thieves stealing fuel. You can also monitor for that.
You would need a fuel flow meter on the fuel line, or a sensor
telling when the furnace is working. Compare with the tank level
decreasing rapidly.
The problem is that the sensor I built on the tank has no power except
batteries: So it only wakes up occasionally and draws nanoamps in
between.
I have completed the warning software that looks for low oil levels,
loss of communication, a failing battery and unexpected changes in oil
level, BUT it cannot do that in real time as the unit is only powered
up for a minute or so every couple of hours.
Depending on how long the batteries last I may increase the frequency
of operation. But it can never be 'real time'
Ah.
What about a small solar panel and rechargeable batteries?
The Natural Philosopher wrote:
Well the daemon runs under xinetd...for sheer laziness. I guess I
could make it UDP.
But I don't know what problem that would solve.
The data would arrive if a single packet got through the fog, whereas
with tcp at least dour packets on sequence need to make it (or get
retried) with UDP you could afford to spray each packet half a dozen
times and if one of them makes it, you're good ...
On 2025-12-12 11:26, The Natural Philosopher wrote:
On 11/12/2025 21:06, Carlos E.R. wrote:
On 2025-12-10 11:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:
c186282 wrote:
Now off to write the software that will look at it for me and warn
me of things by email.
So I can get on with the next project.
You mentioned thieves stealing fuel. You can also monitor for that.
You would need a fuel flow meter on the fuel line, or a sensor
telling when the furnace is working. Compare with the tank level
decreasing rapidly.
The problem is that the sensor I built on the tank has no power except
batteries: So it only wakes up occasionally and draws nanoamps in
between.
I have completed the warning software that looks for low oil levels,
loss of communication, a failing battery and unexpected changes in oil
level, BUT it cannot do that in real time as the unit is only powered
up for a minute or so every couple of hours.
Depending on how long the batteries last I may increase the frequency
of operation. But it can never be 'real time'
Ah.
What about a small solar panel and rechargeable batteries?
The Natural Philosopher wrote:
Well the daemon runs under xinetd...for sheer laziness. I guess I
could make it UDP.
But I don't know what problem that would solve.
The data would arrive if a single packet got through the fog, whereas
with tcp at least dour packets on sequence need to make it (or get
retried) with UDP you could afford to spray each packet half a dozen
times and if one of them makes it, you're good ...
On 12/12/25 06:19, Carlos E.R. wrote:
On 2025-12-12 11:26, The Natural Philosopher wrote:
On 11/12/2025 21:06, Carlos E.R. wrote:
On 2025-12-10 11:24, The Natural Philosopher wrote:
On 10/12/2025 10:02, c186282 wrote:
On 12/10/25 04:14, Andy Burns wrote:
What about a small solar panel and rechargeable batteries?
Seeed sells the "LiPo Rider Plus". After checking
several brands of 'solar charge controllers' these
were the ones I chose to power my field projects.
Most of the others did NOT cap the voltage very
well, or at all, so the sun comes out bright and you
might send 6+ into your 3.1v device.
Combined with a 3 to 5 watt panel they'll keep even
intermittent non-nano-power projects going.
Beware the quality of the batteries though ... got
some no-names, about 50x50x10mm square, that were
generally good - but one DID explode on me, inside
the office building, when I barely touched it. Had
not been charged for months either. Oh well, nothing
to do but watch the big crimson flame .......
Fire control IS a priority with lithiums.
On 11/12/2025 20:59, Carlos E.R. wrote:
On 2025-12-11 19:28, John R Walliker wrote:
On 11/12/2025 18:16, Lars Poulsen wrote:
On 2025-12-11, Daniel James <daniel@me.invalid> wrote:
On 11/12/2025 04:12, c186282 wrote:
... they just run lots of pipes on the outsides of the thick stone >>>>>> walls. Works, but you'd never get away with that in modern
commercial buildings. Things have to look all neat and tidy.
Have you SEEN the Centre Georges Pompidou in Paris?
... or the Lloyds Insurance building in London, for that matter.
I seem to remember hearing that there was an English building code that >>>> REQUIRED outside pipes for water (and sewage?) so that they could be
easily thawed with a blowtorch when they froze in the winter?
No, it was only done to save money.
It seems amazing to me doing that in Britain, were pipes can freeze.
Now I understand the description of an hotel (Devon) in a novel I'm
reading (Ruth Rendell, The secret house of death).
I think the issue is that pre war, many many houses had no water, no
inside toilet, no heating beyond a coal fire no electricity and so on.
Hence they were upgraded to a water tank in the roof and some form of sporadic mains water supply, fed via something coming out of the ground
and into the house.
Drainage was often external - room size was small and the pipes were
just routed outside for ease of installation. And indeed access for
clearing blockages.
Retrofitting modern infrastructure to old houses is massively expensive.
On 11/12/2025 21:18, Carlos E.R. wrote:
On 2025-12-09 11:47, The Natural Philosopher wrote:I sorta tried that without huge success, In fact I am getting up to 12dB variation in signal due to who knows what?
First of all thanks to all those who responded on my first efforts to
put a battery power Pi Pico W outside and have it phone home.
Having eliminated temperature and supply voltage as issues, I delved
into wifi and router logs, and it was clear that it was sometimes
getting a DHCP lease and even occasionally opening a TCP/IP
connections and sending data. And might be dependent on where I
parked the car and the weather.
I tried putting a tin tray behind the router and that made it worse.
Now the layout was that a ground floor router through the window and
the garage was not very good at about 30m range.
Then I remembered I had put an Ethernet port in an upstairs bedroom
by the window in case I wanted to use it as an office.
It was further away - 35m or so - but much less cluttered path. It
just had to go through a corner of the garage.
Instantly the router reported about 8-10dB more signal and almost
reliable comms resulted.
Two ideas.
Some routers can steer the signal horizontally; the technology is
called "MIMO" (https://en.wikipedia.org/wiki/MIMO). You notice because
the router has multiple antenas, maybe four.
Then you can replace the antena on the router or the remote with a
directional WiFi antena. Home made with a box of Pringles. just google
for "pringles wifi antenna". I made one and it actually works. But
maybe they are sold, too.
The setup is all somewhat experimental. At least for now the software
is more or less stable - I have a few hanging daemons if the link goes
down mid message - but that is easily fixed .
...Huh? it can be as exact as your measurements are.
And I knew all that trig would come in handy one day :-)
You can calculate it numerically on a computer, by calculating the
aproximate integral ;-)
No 'approximations' here...
diameter= tankDepth - offset;
radius = diameter * 0.5;
y = echoDepth - offset -radius;
theta = asin( y / radius);
x = radius * cos(theta);
pie= radius * radius * theta;
delta = x * y;
area= (M_PI * radius *radius)/2 - (pie + delta);
volume=(area/(M_PI * radius *radius ))*tankVolume;
That is about ultimately three days of work. It is redundant but I think
gcc can optimise out the intermediary variables that I used to make sure even I could understand it.
What has been encouraging is the pinpoint accuracy of the measurements.
Once in a stable environment the ultrasonics are very precise. something like a mm or two in a couple of metres. Probably more precise than the
speed of sound in air of variable pressures would justify, or indeed the expansion of the oil in warmer temperatures.
LOL.
Maybe I have built the world's most complicated barometer.
On 11/12/2025 21:18, Carlos E.R. wrote:
Two ideas.
Some routers can steer the signal horizontally; the technology is
called "MIMO" (https://en.wikipedia.org/wiki/MIMO). You notice because
the router has multiple antenas, maybe four.
Then you can replace the antena on the router
What antenna on the router?
It's just a wifi bridge with an internal something or other.
https://www.netxl.com/wifi-access-points/mikrotik-routerboard- rb951ui-2nd-wifi-4-access-point/
Its actually very very cheap and has been 'good enough'
; or the remote with a
directional WiFi antena.
That gets complicated. I am trying easy shit first :-)
P Pico W doesn't have an 'antenna' either. Just some PCB traces.
Home made with a box of Pringles. just google for "pringles wifi
antenna". I made one and it actually works. But maybe they are sold, too.
Everything is possible. I am lazy. I do what is necessary to achieve
desired result and no more.
For now I seem to have adequate connectivity.
| Sysop: | DaiTengu |
|---|---|
| Location: | Appleton, WI |
| Users: | 1,089 |
| Nodes: | 10 (0 / 10) |
| Uptime: | 155:07:40 |
| Calls: | 13,921 |
| Calls today: | 2 |
| Files: | 187,021 |
| D/L today: |
3,908 files (988M bytes) |
| Messages: | 2,457,191 |