Is 3 Watts really too much to ask?...

[Jan Panteltje]

On a sunny day (Sat, 8 Jan 2022 14:27:46 -0800 (PST)) it happened Lasse
Langwadt Christensen <langwadt@fonz.dk> wrote in
<8f4240c6-f9ed-465c-85c8-ae2189591f85n@googlegroups.com>:

l=C3=B8rdag den 8. januar 2022 kl. 20.57.15 UTC+1 skrev Jan Panteltje:
On a sunny day (Sat, 08 Jan 2022 21:20:26 +0200) it happened LM
sala...@mail.com> wrote in <2sojtg1il3ind7sj8...@4ax.com>:
On Tue, 04 Jan 2022 21:41:32 -0800, jla...@highlandsniptechnology.com
wrote:

On Wed, 5 Jan 2022 16:25:22 +1100, Sylvia Else <syl...@email.invalid

wrote:

On 05-Jan-22 4:16 pm, jla...@highlandsniptechnology.com wrote:
On Wed, 5 Jan 2022 14:07:30 +1100, Sylvia Else <syl...@email.invalid

wrote:

On 20-Apr-20 3:41 am, Cursitor Doom wrote:
Gentlemen,

in pursuance of what is turning out to be a jinxed project (installing
a
dashcam) I\'m attempting to drop 14.5V (the normal battery voltage whilst

the engine is running) to 5V for the camera. The camera draws at most

300mA so the regulator (an L7805CV) shouldn\'t find that task too much
of
a struggle, since it only has to disspate just under 3 Watts by my

reckoning. I\'d have thought this reasonably large heatsink (see 20p
piece
for scale comparison) would be overkill. Unfortunately it isn\'t, though.

Even with a low ambient temp of about 65\'F it gets a bit too hot to
touch
after a few minutes, so once in the car in a couple of months with
a
T_amb north of 100\'F, it hasn\'t a hope in hell of preventing the reg
from
going up in smoke.
Apart from advising me to permanantly give up electronics, has anyone
got
any constructive suggestions to make here?
TIA.

Not sure \"too hot to touch\" is a good measure, because a good conductor

of heat will feel too hot even at a modest temperature.

If a single bigger heat sink is not an option, you could use a 7809
or
7810 to drive the 7805, splitting the heat output roughly between them.


Sylvia.

There are cute little 3-pin potted switching regulators that drop into

a 7805 footprint.




I hadn\'t come across those. Cursitor might be interested in

https://www.digikey.com/en/products/detail/mornsun-america-llc/K7805M-1000R3/13168132


Sylvia.

Check this one out:

https://www.digikey.com/en/products/detail/xp-power/SRH05S12/8021461?s=3DN4IgTCBcDaIMoCUASAGArHAjBAugXyA


72 volts max input! I use it to drop 48 volts down to a more managable

12.
I once wondered how can I get an input with widest voltage range.
Those 70V regulators help a lot in that.
I just ue LM2596
needs one inductor, some caps, some resistors, it is a 150 kHz switcher, 45
V max input.
There are fixed voltage versions, but by adding resistors to the 3.3 V version
feedback
you can make any output voltage > 3.3V.

https://www.ebay.com/itm/353775582161

Hard to beat that price!

something like this is convinient for sticking on a prototype board

https://www.ebay.com/itm/224151690136

I have a few of different kind ebay buck and buck/boost converters,
these have 10 turn trimpots to set voltage and currrent limits,
https://www.ebay.com/itm/274548626280
I use those to charge batteries for example.

boost:
https://www.ebay.com/itm/192032921916

And not to forget the \'400 kV\' one:
https://www.ebay.com/itm/284317013448
well, 400 kV probably not quite, but large sparks it makes.

 

[Jan Panteltje]

On a sunny day (Sat, 08 Jan 2022 13:27:42 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<1rvjtg90lvi08pttscckrnbmf68ul6jcll@4ax.com>:

On Sat, 08 Jan 2022 19:55:42 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 21:20:26 +0200) it happened LM
sala.nimi@mail.com> wrote in <2sojtg1il3ind7sj8jutqcsh811dqit2vd@4ax.com>:

On Tue, 04 Jan 2022 21:41:32 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Wed, 5 Jan 2022 16:25:22 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 05-Jan-22 4:16 pm, jlarkin@highlandsniptechnology.com wrote:
On Wed, 5 Jan 2022 14:07:30 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 20-Apr-20 3:41 am, Cursitor Doom wrote:
Gentlemen,

in pursuance of what is turning out to be a jinxed project (installing a
dashcam) I\'m attempting to drop 14.5V (the normal battery voltage whilst
the engine is running) to 5V for the camera. The camera draws at most
300mA so the regulator (an L7805CV) shouldn\'t find that task too much of
a struggle, since it only has to disspate just under 3 Watts by my
reckoning. I\'d have thought this reasonably large heatsink (see 20p piece
for scale comparison) would be overkill. Unfortunately it isn\'t, though.
Even with a low ambient temp of about 65\'F it gets a bit too hot to touch
after a few minutes, so once in the car in a couple of months with a
T_amb north of 100\'F, it hasn\'t a hope in hell of preventing the reg from
going up in smoke.
Apart from advising me to permanantly give up electronics, has anyone got
any constructive suggestions to make here?
TIA.

Not sure \"too hot to touch\" is a good measure, because a good conductor
of heat will feel too hot even at a modest temperature.

If a single bigger heat sink is not an option, you could use a 7809 or
7810 to drive the 7805, splitting the heat output roughly between them.

Sylvia.

There are cute little 3-pin potted switching regulators that drop into
a 7805 footprint.




I hadn\'t come across those. Cursitor might be interested in

https://www.digikey.com/en/products/detail/mornsun-america-llc/K7805M-1000R3/13168132

Sylvia.

Check this one out:

https://www.digikey.com/en/products/detail/xp-power/SRH05S12/8021461?s=N4IgTCBcDaIMoCUASAGArHAjBAugXyA

72 volts max input! I use it to drop 48 volts down to a more managable
12.
I once wondered how can I get an input with widest voltage range.
Those 70V regulators help a lot in that.

I just ue LM2596
needs one inductor, some caps, some resistors, it is a 150 kHz switcher, 45 V max input.
There are fixed voltage versions, but by adding resistors to the 3.3 V version feedback
you can make any output voltage > 3.3V.

We use LM2576HV-ADJ, which tolerates 60 volts in and is rated for 3
amps out. It runs at 52 KHz, so needs huge L and C.

A few of our products start with a kilowatt or so of 48 volt MeanWell
supply, so we need to step down to 12 or 15 volts for secondary linear
and switching regs.

https://www.dropbox.com/s/ajmnj0j5h45lfbl/P902B_5.jpg?raw=1

Nice box, fan blows out via the back?
Yes those Meanswell, I have 7 or more? 7 V versions and series those
if needed.
http://panteltje.com/pub/meanwell_7.5V_20A_IMG_5189.JPG
You can turn those up to more than 8 V output BTW.
Very cheap!

I yam what I yam - Popeye

 

[server]

On Sun, 09 Jan 2022 08:17:39 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 13:27:42 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
1rvjtg90lvi08pttscckrnbmf68ul6jcll@4ax.com>:

On Sat, 08 Jan 2022 19:55:42 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 21:20:26 +0200) it happened LM
sala.nimi@mail.com> wrote in <2sojtg1il3ind7sj8jutqcsh811dqit2vd@4ax.com>:

On Tue, 04 Jan 2022 21:41:32 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Wed, 5 Jan 2022 16:25:22 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 05-Jan-22 4:16 pm, jlarkin@highlandsniptechnology.com wrote:
On Wed, 5 Jan 2022 14:07:30 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 20-Apr-20 3:41 am, Cursitor Doom wrote:
Gentlemen,

in pursuance of what is turning out to be a jinxed project (installing a
dashcam) I\'m attempting to drop 14.5V (the normal battery voltage whilst
the engine is running) to 5V for the camera. The camera draws at most
300mA so the regulator (an L7805CV) shouldn\'t find that task too much of
a struggle, since it only has to disspate just under 3 Watts by my
reckoning. I\'d have thought this reasonably large heatsink (see 20p piece
for scale comparison) would be overkill. Unfortunately it isn\'t, though.
Even with a low ambient temp of about 65\'F it gets a bit too hot to touch
after a few minutes, so once in the car in a couple of months with a
T_amb north of 100\'F, it hasn\'t a hope in hell of preventing the reg from
going up in smoke.
Apart from advising me to permanantly give up electronics, has anyone got
any constructive suggestions to make here?
TIA.

Not sure \"too hot to touch\" is a good measure, because a good conductor
of heat will feel too hot even at a modest temperature.

If a single bigger heat sink is not an option, you could use a 7809 or
7810 to drive the 7805, splitting the heat output roughly between them.

Sylvia.

There are cute little 3-pin potted switching regulators that drop into
a 7805 footprint.




I hadn\'t come across those. Cursitor might be interested in

https://www.digikey.com/en/products/detail/mornsun-america-llc/K7805M-1000R3/13168132

Sylvia.

Check this one out:

https://www.digikey.com/en/products/detail/xp-power/SRH05S12/8021461?s=N4IgTCBcDaIMoCUASAGArHAjBAugXyA

72 volts max input! I use it to drop 48 volts down to a more managable
12.
I once wondered how can I get an input with widest voltage range.
Those 70V regulators help a lot in that.

I just ue LM2596
needs one inductor, some caps, some resistors, it is a 150 kHz switcher, 45 V max input.
There are fixed voltage versions, but by adding resistors to the 3.3 V version feedback
you can make any output voltage > 3.3V.

We use LM2576HV-ADJ, which tolerates 60 volts in and is rated for 3
amps out. It runs at 52 KHz, so needs huge L and C.

A few of our products start with a kilowatt or so of 48 volt MeanWell
supply, so we need to step down to 12 or 15 volts for secondary linear
and switching regs.

https://www.dropbox.com/s/ajmnj0j5h45lfbl/P902B_5.jpg?raw=1

Nice box, fan blows out via the back?
Yes those Meanswell, I have 7 or more? 7 V versions and series those
if needed.
http://panteltje.com/pub/meanwell_7.5V_20A_IMG_5189.JPG
You can turn those up to more than 8 V output BTW.
Very cheap!

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.



--

I yam what I yam - Popeye

 

[Jan Panteltje]

On a sunny day (Sun, 09 Jan 2022 07:54:59 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<hh0mtg1bqpsafq353mkp8cu43rv7hojhju@4ax.com>:

On Sun, 09 Jan 2022 08:17:39 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 13:27:42 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
1rvjtg90lvi08pttscckrnbmf68ul6jcll@4ax.com>:

On Sat, 08 Jan 2022 19:55:42 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 21:20:26 +0200) it happened LM
sala.nimi@mail.com> wrote in <2sojtg1il3ind7sj8jutqcsh811dqit2vd@4ax.com>:

On Tue, 04 Jan 2022 21:41:32 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Wed, 5 Jan 2022 16:25:22 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 05-Jan-22 4:16 pm, jlarkin@highlandsniptechnology.com wrote:
On Wed, 5 Jan 2022 14:07:30 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 20-Apr-20 3:41 am, Cursitor Doom wrote:
Gentlemen,

in pursuance of what is turning out to be a jinxed project (installing a
dashcam) I\'m attempting to drop 14.5V (the normal battery voltage whilst
the engine is running) to 5V for the camera. The camera draws at most
300mA so the regulator (an L7805CV) shouldn\'t find that task too much of
a struggle, since it only has to disspate just under 3 Watts by my
reckoning. I\'d have thought this reasonably large heatsink (see 20p piece
for scale comparison) would be overkill. Unfortunately it isn\'t, though.
Even with a low ambient temp of about 65\'F it gets a bit too hot to touch
after a few minutes, so once in the car in a couple of months with a
T_amb north of 100\'F, it hasn\'t a hope in hell of preventing the reg from
going up in smoke.
Apart from advising me to permanantly give up electronics, has anyone got
any constructive suggestions to make here?
TIA.

Not sure \"too hot to touch\" is a good measure, because a good conductor
of heat will feel too hot even at a modest temperature.

If a single bigger heat sink is not an option, you could use a 7809 or
7810 to drive the 7805, splitting the heat output roughly between them.

Sylvia.

There are cute little 3-pin potted switching regulators that drop into
a 7805 footprint.




I hadn\'t come across those. Cursitor might be interested in

https://www.digikey.com/en/products/detail/mornsun-america-llc/K7805M-1000R3/13168132

Sylvia.

Check this one out:

https://www.digikey.com/en/products/detail/xp-power/SRH05S12/8021461?s=N4IgTCBcDaIMoCUASAGArHAjBAugXyA

72 volts max input! I use it to drop 48 volts down to a more managable
12.
I once wondered how can I get an input with widest voltage range.
Those 70V regulators help a lot in that.

I just ue LM2596
needs one inductor, some caps, some resistors, it is a 150 kHz switcher, 45 V max input.
There are fixed voltage versions, but by adding resistors to the 3.3 V version feedback
you can make any output voltage > 3.3V.

We use LM2576HV-ADJ, which tolerates 60 volts in and is rated for 3
amps out. It runs at 52 KHz, so needs huge L and C.

A few of our products start with a kilowatt or so of 48 volt MeanWell
supply, so we need to step down to 12 or 15 volts for secondary linear
and switching regs.

https://www.dropbox.com/s/ajmnj0j5h45lfbl/P902B_5.jpg?raw=1

Nice box, fan blows out via the back?
Yes those Meanswell, I have 7 or more? 7 V versions and series those
if needed.
http://panteltje.com/pub/meanwell_7.5V_20A_IMG_5189.JPG
You can turn those up to more than 8 V output BTW.
Very cheap!




Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).

 

[server]

On Sun, 09 Jan 2022 18:30:17 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 07:54:59 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
hh0mtg1bqpsafq353mkp8cu43rv7hojhju@4ax.com>:

On Sun, 09 Jan 2022 08:17:39 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 13:27:42 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
1rvjtg90lvi08pttscckrnbmf68ul6jcll@4ax.com>:

On Sat, 08 Jan 2022 19:55:42 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 08 Jan 2022 21:20:26 +0200) it happened LM
sala.nimi@mail.com> wrote in <2sojtg1il3ind7sj8jutqcsh811dqit2vd@4ax.com>:

On Tue, 04 Jan 2022 21:41:32 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Wed, 5 Jan 2022 16:25:22 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 05-Jan-22 4:16 pm, jlarkin@highlandsniptechnology.com wrote:
On Wed, 5 Jan 2022 14:07:30 +1100, Sylvia Else <sylvia@email.invalid
wrote:

On 20-Apr-20 3:41 am, Cursitor Doom wrote:
Gentlemen,

in pursuance of what is turning out to be a jinxed project (installing a
dashcam) I\'m attempting to drop 14.5V (the normal battery voltage whilst
the engine is running) to 5V for the camera. The camera draws at most
300mA so the regulator (an L7805CV) shouldn\'t find that task too much of
a struggle, since it only has to disspate just under 3 Watts by my
reckoning. I\'d have thought this reasonably large heatsink (see 20p piece
for scale comparison) would be overkill. Unfortunately it isn\'t, though.
Even with a low ambient temp of about 65\'F it gets a bit too hot to touch
after a few minutes, so once in the car in a couple of months with a
T_amb north of 100\'F, it hasn\'t a hope in hell of preventing the reg from
going up in smoke.
Apart from advising me to permanantly give up electronics, has anyone got
any constructive suggestions to make here?
TIA.

Not sure \"too hot to touch\" is a good measure, because a good conductor
of heat will feel too hot even at a modest temperature.

If a single bigger heat sink is not an option, you could use a 7809 or
7810 to drive the 7805, splitting the heat output roughly between them.

Sylvia.

There are cute little 3-pin potted switching regulators that drop into
a 7805 footprint.




I hadn\'t come across those. Cursitor might be interested in

https://www.digikey.com/en/products/detail/mornsun-america-llc/K7805M-1000R3/13168132

Sylvia.

Check this one out:

https://www.digikey.com/en/products/detail/xp-power/SRH05S12/8021461?s=N4IgTCBcDaIMoCUASAGArHAjBAugXyA

72 volts max input! I use it to drop 48 volts down to a more managable
12.
I once wondered how can I get an input with widest voltage range.
Those 70V regulators help a lot in that.

I just ue LM2596
needs one inductor, some caps, some resistors, it is a 150 kHz switcher, 45 V max input.
There are fixed voltage versions, but by adding resistors to the 3.3 V version feedback
you can make any output voltage > 3.3V.

We use LM2576HV-ADJ, which tolerates 60 volts in and is rated for 3
amps out. It runs at 52 KHz, so needs huge L and C.

A few of our products start with a kilowatt or so of 48 volt MeanWell
supply, so we need to step down to 12 or 15 volts for secondary linear
and switching regs.

https://www.dropbox.com/s/ajmnj0j5h45lfbl/P902B_5.jpg?raw=1

Nice box, fan blows out via the back?
Yes those Meanswell, I have 7 or more? 7 V versions and series those
if needed.
http://panteltje.com/pub/meanwell_7.5V_20A_IMG_5189.JPG
You can turn those up to more than 8 V output BTW.
Very cheap!




Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).

Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.



--

I yam what I yam - Popeye

 

[Jan Panteltje]

On a sunny day (Sun, 09 Jan 2022 10:46:46 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<5bbmtg59advmdlu0jpc1md0uub02fo38t8@4ax.com>:

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).




Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.

Where I am now the garden is much bigger, and at the end there is a wooden hut,
I keep my bike, grass mower and stuff in there, some electronics could find a place there.
Unfortunately big brothel had made the place a no-fly zone for drones, too close
to Leeuwarden mil airport, and F35s making a lot of noise coming over very low.
OTOH there are grapes growing next to that hut, and those are not sour

 

[server]

On Mon, 10 Jan 2022 06:37:45 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 10:46:46 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
5bbmtg59advmdlu0jpc1md0uub02fo38t8@4ax.com>:

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).




Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.

Where I am now the garden is much bigger, and at the end there is a wooden hut,
I keep my bike, grass mower and stuff in there, some electronics could find a place there.
Unfortunately big brothel had made the place a no-fly zone for drones, too close
to Leeuwarden mil airport, and F35s making a lot of noise coming over very low.
OTOH there are grapes growing next to that hut, and those are not sour

We grow lemons. The local Meyer lemons aren\'t actually very sour. They
make dynamite lemon pies.

https://www.dropbox.com/s/wrg2c9g5g78thu2/Lemons_Fog.jpg?raw=1



--

I yam what I yam - Popeye

 

[Jan Panteltje]

On a sunny day (Sun, 09 Jan 2022 23:24:55 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<rdnntgl54hen8uks5mmh2cj1bcjre3kcg2@4ax.com>:

On Mon, 10 Jan 2022 06:37:45 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 10:46:46 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
5bbmtg59advmdlu0jpc1md0uub02fo38t8@4ax.com>:

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).




Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.

Where I am now the garden is much bigger, and at the end there is a wooden hut,
I keep my bike, grass mower and stuff in there, some electronics could find a place there.
Unfortunately big brothel had made the place a no-fly zone for drones, too close
to Leeuwarden mil airport, and F35s making a lot of noise coming over very low.
OTOH there are grapes growing next to that hut, and those are not sour

We grow lemons. The local Meyer lemons aren\'t actually very sour. They
make dynamite lemon pies.

https://www.dropbox.com/s/wrg2c9g5g78thu2/Lemons_Fog.jpg?raw=1

Nice!

 

[server]

On Mon, 10 Jan 2022 07:55:58 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 23:24:55 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
rdnntgl54hen8uks5mmh2cj1bcjre3kcg2@4ax.com>:

On Mon, 10 Jan 2022 06:37:45 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 10:46:46 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
5bbmtg59advmdlu0jpc1md0uub02fo38t8@4ax.com>:

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).




Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.

Where I am now the garden is much bigger, and at the end there is a wooden hut,
I keep my bike, grass mower and stuff in there, some electronics could find a place there.
Unfortunately big brothel had made the place a no-fly zone for drones, too close
to Leeuwarden mil airport, and F35s making a lot of noise coming over very low.
OTOH there are grapes growing next to that hut, and those are not sour

We grow lemons. The local Meyer lemons aren\'t actually very sour. They
make dynamite lemon pies.

https://www.dropbox.com/s/wrg2c9g5g78thu2/Lemons_Fog.jpg?raw=1

Nice!

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

I\'m still stunned by the 3-dimensionality of the coast and the
mountains. People who were born here barely notice.

Search youtube for drone videos of Pacifica, before it falls into the
ocean.



--

I yam what I yam - Popeye

 

[Jan Panteltje]

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<aieotgd50q2np1e1kqrvr4h7pcq1u5hd40@4ax.com>:

On Mon, 10 Jan 2022 07:55:58 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 23:24:55 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
rdnntgl54hen8uks5mmh2cj1bcjre3kcg2@4ax.com>:

On Mon, 10 Jan 2022 06:37:45 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 09 Jan 2022 10:46:46 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
5bbmtg59advmdlu0jpc1md0uub02fo38t8@4ax.com>:

Cheap and good. The 1 KW 48v supply costs us $156 and it can actually
make a good bit more than 1 KW.

The three class-D amps in that box each have their own fan on the
bottom. That air flow cools the big toroids too.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1

What really needs air flow is the inductors. The two toroids are
sendust to keep switching losses down.

We\'re designing a new 3U power chassis now, sort of a next gen modular
power system. We ordered a mess of custom plastic pieces from Tap
Plastics to make a mockup chassis. We\'ll play with placements and fans
and holes and heat sinks to sorta optimize it. We have no tools to
simulate this sort of thermal thing.

https://www.dropbox.com/s/0haqesun81ecwlk/28R941A_sh1.jpg?raw=1

https://www.dropbox.com/s/lknrpold45zzt2e/28R941A_sh2.jpg?raw=1

I should have specified colors.

I love Tap Plastics.

Indeed high power inductors get hot,
here is a different kind of air cooling:
http://panteltje.com/pub/h501s_drone_remote_power_drone_side_IMG_6278.JPG
toroid and diodes cooled by the propellor airflow
power via thin coax with about 100 kHz few hundred volt, transformed down to 7.5V 10 A at the drone.
http://panteltje.com/pub/h501s_drone_remote_power_flight_test_1_IMG_6274.JPG
from, yes, Meanwells powering an LC converter:
http://panteltje.com/pub/h501s_drone_remote_power_test_ground_control_1_IMG_6276.JPG

Keeps the drone in the air indefinately, for example with an antenne (RF via same coax) or camera (wireless).




Outdoor lab! With all that grass, I\'m guessing that it might rain
sometimes.

Where I am now the garden is much bigger, and at the end there is a wooden hut,
I keep my bike, grass mower and stuff in there, some electronics could find a place there.
Unfortunately big brothel had made the place a no-fly zone for drones, too close
to Leeuwarden mil airport, and F35s making a lot of noise coming over very low.
OTOH there are grapes growing next to that hut, and those are not sour

We grow lemons. The local Meyer lemons aren\'t actually very sour. They
make dynamite lemon pies.

https://www.dropbox.com/s/wrg2c9g5g78thu2/Lemons_Fog.jpg?raw=1

Nice!

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

I\'m still stunned by the 3-dimensionality of the coast and the
mountains. People who were born here barely notice.

Search youtube for drone videos of Pacifica, before it falls into the
ocean.

Here a view of part of the garden, that glass house on the left is from the neighbor,
he also grows some plants from seeds I gave him there.
http://panteltje.com/pub/garden_IXIMG_0763.JPG
it is freeing now, note the white on the roof.
Yes Leeuwarden and the rest of this part is all protected by dikes and pumps.
I cannot see the sea from here but I can see the flashes of the lighthouse sometimes,
Not many flowers now in winter.
Recent storm broke some of those high white plumes,,,
View from the upstairs computer room at the front:
http://panteltje.com/pub/easter_snow_st_jacobiparochie_IXIMG_0677.jpg
those supported trees carry apples.
Yes,... big earthquake and what\'s it called Andreas fault? and there you go!

 

[Jan Panteltje]

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<aieotgd50q2np1e1kqrvr4h7pcq1u5hd40@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.

 

[Jeroen Belleman]

On 2022-01-10 19:53, Jan Panteltje wrote:

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
aieotgd50q2np1e1kqrvr4h7pcq1u5hd40@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.

Not to worry! We\'ll deal with them when they develop a taste for little
red riding hood\'s grandma.

Jeroen Belleman

 

[server]

On Mon, 10 Jan 2022 18:53:42 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
aieotgd50q2np1e1kqrvr4h7pcq1u5hd40@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.

We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and
another that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I
hear that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.



--

I yam what I yam - Popeye

 

[Flyguy]

On Monday, January 10, 2022 at 7:16:40 PM UTC-8, jla...@highlandsniptechnology.com wrote:

On Mon, 10 Jan 2022 18:53:42 GMT, Jan Panteltje
pNaonSt...@yahoo.com> wrote:

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jla...@highlandsniptechnology.com wrote in
aieotgd50q2np1e1k...@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.


We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and
another that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I
hear that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.
--

I yam what I yam - Popeye

They\'ve been saying that SF has gone to the dogs, but maybe it is the lions instead.

 

[server]

On Mon, 10 Jan 2022 20:08:23 -0800 (PST), Flyguy
<soar2morrow@yahoo.com> wrote:

On Monday, January 10, 2022 at 7:16:40 PM UTC-8, jla...@highlandsniptechnology.com wrote:
On Mon, 10 Jan 2022 18:53:42 GMT, Jan Panteltje
pNaonSt...@yahoo.com> wrote:

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jla...@highlandsniptechnology.com wrote in
aieotgd50q2np1e1k...@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.


We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and
another that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I
hear that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.
--

I yam what I yam - Popeye

They\'ve been saying that SF has gone to the dogs, but maybe it is the lions instead.

I think it is illegal to walk about in public without a kid or a dog.



--

I yam what I yam - Popeye

 

[Jan Panteltje]

On a sunny day (Mon, 10 Jan 2022 19:16:30 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<31tptgd6d1g0rmmopdmuo816iubqk1ap6j@4ax.com>:

On Mon, 10 Jan 2022 18:53:42 GMT, Jan Panteltje
pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Mon, 10 Jan 2022 06:01:58 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
aieotgd50q2np1e1kqrvr4h7pcq1u5hd40@4ax.com>:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and just
about, or under, sea level. From my house, I used to look up at ships
on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north.
But now we have a few wolves it seems
those are spreading over Europe, sort of protected by the green pollyticksians,
how idiotic those greens can be, those wolves attack sheep and cause damage to farmers.



We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and
another that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I
hear that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.

Somebody shot a wolf here a few weeks back, almost a witchhunt started
for the \'bad\' guy whodidit.
I would kill it too if it came up to me!
Very strange times we live in.

 

[John Doe]

Jan Panteltje wrote:

jlarkin@highlandsniptechnology.com wrote:
Jan Panteltje wrote:
jlarkin@highlandsniptechnology.com wrote:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and
just about, or under, sea level. From my house, I used to look up at
ships on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north. But now we have a
few wolves it seems those are spreading over Europe, sort of protected
by the green pollyticksians, how idiotic those greens can be, those
wolves attack sheep and cause damage to farmers.

It\'s called \"evil\".

We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and another
that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I hear
that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.

Somebody shot a wolf here a few weeks back, almost a witchhunt started
for the \'bad\' guy whodidit. I would kill it too if it came up to me!
Very strange times we live in.

The transgender bullies beating up on girls in sports issue is the most
outrageous example ever. It\'s like the Twilight Zone. I always liked the
Twilight Zone.

We have skunks, raccoons, and possums. The skunks are a hazard/danger to
backyard pets, they zapped my next-door neighbor\'s dog. Skunks and
raccoons are both rabies vectors. Raccoons will kill cats that try to
defend their territory/food, and they snack on kittens. People who feed
unneutered cats can rest assured they are not causing a cat population
explosion since the raccoons eat the kittens. And Tomcats are known to kill
kittens produced by other tomcats.

 

[Phil Hobbs]

John Doe wrote:

Jan Panteltje wrote:

jlarkin@highlandsniptechnology.com wrote:
Jan Panteltje wrote:
jlarkin@highlandsniptechnology.com wrote:

Leeuwarden reminds me of where I grew up in New Orleans. Flat and
just about, or under, sea level. From my house, I used to look up at
ships on the Mississippi. I bet we had more bugs and alligators and
hurricanes than you do.

None of that here, we are located way more north. But now we have a
few wolves it seems those are spreading over Europe, sort of protected
by the green pollyticksians, how idiotic those greens can be, those
wolves attack sheep and cause damage to farmers.

It\'s called \"evil\".

We lately have a lot of coyotes in San Francisco. They have been seen
commuting across the Golden Gate Bridge.

On a recent walk, we saw a sign that said Coyote Warning... and another
that said Missing Cat...

We had a mountain lion a few blocks away from the house.

https://www.dropbox.com/s/j9n5vm3r4mfjnyo/ML2.jpg?raw=1

https://www.dropbox.com/s/hckvp0g4wh7gp3u/ML4.jpg?raw=1

https://www.dropbox.com/s/akbuang0jw3f481/ML6.jpg?raw=1

They trucked it south and let it go in the Santa Cruz mountains. I hear
that that same cat has come back.

We have possum, skunks, snakes, raccoons, ravens, hawks, squirrels,
and even a wild turkey roaming the streets. And a couple of flocks of
wild parrots.

Somebody shot a wolf here a few weeks back, almost a witchhunt started
for the \'bad\' guy whodidit. I would kill it too if it came up to me!
Very strange times we live in.

The transgender bullies beating up on girls in sports issue is the most
outrageous example ever. It\'s like the Twilight Zone. I always liked the
Twilight Zone.

We have skunks, raccoons, and possums. The skunks are a hazard/danger to
backyard pets, they zapped my next-door neighbor\'s dog.

One time we were dog-sitting a friend\'s husky/collie mix. I let him out
the basement door about midnight to go do his business, and he decided
to investigate this interesting stripy animal....

He ran straight back toward me, running the side of his head along the
wet grass as he went. (It would have been very funny to see if I hadn\'t
known why he was doing it.)

Fortunately I had a gallon of white vinegar in the laundry room, so I
grabbed a towel and doused him. By the time I was done, he looked and
smelled like a giant furry brown pickle, but the skunk scent was
completely gone.

(Skunk scent is hydrolyzed by mild acids--a quart of lemon juice also
works. Yes, that means that dog got skunked at our house twice.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Anthony William Sloman]

On Tuesday, January 11, 2022 at 6:48:23 PM UTC+11, Phil Hobbs wrote:

John Doe wrote:
Jan Panteltje wrote:
jla...@highlandsniptechnology.com wrote:
Jan Panteltje wrote:
jla...@highlandsniptechnology.com wrote:

<snip>

We have skunks, raccoons, and possums. The skunks are a hazard/danger to
backyard pets, they zapped my next-door neighbor\'s dog.
One time we were dog-sitting a friend\'s husky/collie mix. I let him out
the basement door about midnight to go do his business, and he decided
to investigate this interesting stripy animal....

He ran straight back toward me, running the side of his head along the
wet grass as he went. (It would have been very funny to see if I hadn\'t
known why he was doing it.)

Fortunately I had a gallon of white vinegar in the laundry room, so I
grabbed a towel and doused him. By the time I was done, he looked and
smelled like a giant furry brown pickle, but the skunk scent was
completely gone.

(Skunk scent is hydrolyzed by mild acids--a quart of lemon juice also
works. Yes, that means that dog got skunked at our house twice.)

The active agents is tertiary butyl mercaptan - a thiol. The HS link is pretty easy to break.

I worked out a way of synthesising a precusor from thiourea and tertiary butyl chloride when I was an undergraduate, and we used it in a couple of student pranks.
Bicarbonate of soda freed up the thiol from an alcohol solution of the thiouronium salt precursor without hydrolysing the thiol link.

--
Bill Sloman, Sydney