Low Current Draw Netbook

Started by KK0G, October 28, 2013, 10:29:48 PM

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KK0G

#15

Quote from: KC3AOL on October 30, 2013, 09:56:21 AM
It's not out yet, but I'd probably go with this:
http://www.anandtech.com/show/7427/acer-launches-iconia-w4-tablet-with-windows-81

You can use it touch screen only or you can hook up a USB keyboard/mouse.  Maybe something like this:
http://www.amazon.com/HDE-Foldable-Portable-Roll-Up-Keyboard/dp/B001GC9C9Q/ref=sr_1_1?ie=UTF8&qid=1383141084&sr=8-1&keywords=flexible+keyboard

You could go Bluetooth, but that's going to draw some power as well.

One of the main things you'll want to low current draw is a Solid State Drive (SSD) instead of the standard hard drive that spins disks.
That set up would work pretty well in a shack environment but finding a hard, flat surface out in the field to set up the tablet at a good viewing angle plus the key board could be problematic, not to mention more pieces to lose, break, fail, etc. I still think a traditional fold up style netbook might be the way to go. I'm really liking the older Asus line, the fact that I can pick up a used one pretty cheap is a big plus also.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

KC3AOL

#16
Quote from: KK0G on October 30, 2013, 10:11:58 AM
That set up would work pretty well in a shack environment but finding a hard, flat surface out in the field to set up the tablet at a good viewing angle plus the key board could be problematic, not to mention more pieces to lose, break, fail, etc. I still think a traditional fold up style netbook might be the way to go. I'm really liking the older Asus line, the fact that I can pick up a used one pretty cheap is a big plus also.
Setting it up in the field seems like it would be pretty easy to me (or you could just hold it), but that's up to you.  The article also mentioned accessories that could make it laptop-like when you want it to be:
QuoteAcer also has several peripherals for the new tablet, including a Keyboard Cover, protective film, a "responsive" passive stylus, power bank, and an adapter kit with bag. Perhaps more interesting are the Crunch Keyboard and Crunch Cover. The Crunch Keyboard is a soft synthetic leather cover that folds out as well as functions as a tablet stand. It measures 0.21" thick (5.3mm) and works via Bluetooth 3.0, with recharging via micro USB, so while it doesn't directly provide more battery life to the tablet it doesn't require a physical connection and won't reduce battery life. The Crunch Cover is made of durable microfibers and folds into a stand for the tablet, with several angles available it keeps all of the ports open and comes in several different colors. Acer doesn't mention pricing on any of the accessories, so we'll have to wait and see how much they cost.

The main power hogs on laptops/tablets/etc are the screen and the hard drive.  Obviously, a smaller screen will use less power and I've already mentioned the SSD.  If you could find a computer with an e-ink display, that would use way less power, but I've only seen that on e-readers....probably because the refresh rate is extremely slow and it's black/white only.

KK0G

I've since discovered a quick and easy trick to finding the power supply requirements of practically any laptop or netbook; do a Google image search on the computer in questions ac adapter and read the specs printed right on the adapter. Example: "Asus Eee PC AC Adapter". Granted it's not perfect but it's by far the most reliable method I've found for finding laptop power requirements.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

IT Tech

#18
Quote from: KK0G on October 29, 2013, 10:50:29 AM
Quote from: Lamewolf on October 29, 2013, 09:20:13 AM
Use CW and a QRP radio and there will ne no need to worry about communications !  ;)


I just love the idea of a complete station that will fit in a coat pocket or spare pocket on my bug out pack.    They do make that, it is called a Cell Phone!


Either way, the swr is in good shape and no tuner needed ! 

What does the SWR have to do with transmitting?



When dealing with transmitters, it is not the SWR as measured by a SWR bridge that counts, but the VSWR which is measured with an ammeter.


KK0G

Quote from: IT Tech on January 19, 2014, 12:34:23 PM

Quote from: KK0G on October 29, 2013, 10:50:29 AM
Quote from: Lamewolf on October 29, 2013, 09:20:13 AM
Use CW and a QRP radio and there will ne no need to worry about communications !  ;)


I just love the idea of a complete station that will fit in a coat pocket or spare pocket on my bug out pack.    They do make that, it is called a Cell Phone!


Either way, the swr is in good shape and no tuner needed ! 

What does the SWR have to do with transmitting?



When dealing with transmitters, it is not the SWR as measured by a SWR bridge that counts, but the VSWR which is measured with an anemometer.

Windspeed?? ???
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

IT Tech

Quote from: Flatus on October 29, 2013, 12:41:10 PM
I am new (waiting on my callsign to be published on FCC.gov) but I have an easydigi interface to do PSK31 on my iphone and my handheld baofeng (cheap but works well) HT. Aren't there some packet radio apps (pocketpacket?) for the iphone that allow you to have a software based packet controller? Forgive my ignorance if packet radio isnt allowed on 2m or 70cm I'm still trying to figure all of this out. Sounds like an iPhone or Android would be a good choice for mutiple reasons (GPS, reference, easy to charge, spare batteries, etc) for digital comms on the go?

i WILL try to explain some things if you don't mind...

Did you ever hear of APRS?  Do you know what the acronym stands for?
Automatic Packet Reporting System

Packet is done on 2 meters, but in the simplex portion of the band.
It entails my antenna and radio talking to your antenna and radio and does not use a FM repeater like the OP's you are used to with 2 meter FM repeaters and voice communications.

Your main limitation would be battery life, since the phone would use more power being energized all the time to run packet.
The Beofung would probably last 45 minutes before the battery was dead.

I would suggest that you join a  amateur radio club, find a club member that operates digital modes, have him Elmer you.   There is a lot to be learned and the learning curve is too steep for someone not involved in communications to learn by themselves.

Your answer was not dumb, it just needed some help.

Packet is a digital form of store and forward - kind of like a Igate that looks for the nearest available Igate to transmit it's information to.
http://info.aprs.net/index.php?title=IGate

An IGate is a type of gateway APRS station. It is similar to a network router in the TCP/IP world, or to a "voting receiver" in a wide-area radio repeater network. The IGate's job is to selectively allow packets to cross between the APRS-IS and the local RF network.

An IGate will require the following capabilities:

    RF receive (and optionally send)
    Terminal Node Controller aka TNC (may be hardware or software)
    Internet access and a connection to the Internet
    A computer or processor of some sort to implement the IGate operation ..

RF --> APRS-IS

Going from RF to APRS-IS is the simpler of the two operations. The IGate station needs to successfully connect to APRS-IS which requires a rudimentary password. Packets received via RF are sent out on the APRS-IS side. IGate implementations take care of reformatting the packet for the APRS-IS.

APRS-IS --> RF

The technical parts are not difficult but the limitations of the RF channel and regulatory restrictions attendant with radio transmissions make things more difficult. Many IGate implementations will only send to RF those packets destined for stations that have been recently heard on the RF side or that are in a list of designated destination stations. As an IGate operator you are responsible for the content of the packets transmitted by your station on RF, and you should coordinate with your local or regional APRS technical coordinators to ensure that an outbound RF IGate is desirable and won't actually cause problems by creating packet duplication and/or collisions.

IT Tech

Quote from: KK0G on January 19, 2014, 12:40:52 PM


Windspeed?? ???

No you got me on that one - the auto correct changed the spelling - it should have been, since my spelling isn't the greatest, lets change that to a Thru Line power meter.

An Antenna Bridge just compares what is seen at the end of the line to a known measurement.
It is not by any means an exact way to measure performance.
What counts more is the amount of power that is absorbed by the antenna and how much of the power is reflected back into the line and how much power is lost in the line.
The ammeter is usually placed directly behind the antenna and gives you actual readings at the end of the feed line instead of being measured at the transmitter.

IT Tech

Re: Low Current Draw Netbook

I will relate some things that I have experienced and maybe you have too...

If I was going to rely on the internet for anything, after a major disaster or apocalypse it would have to happen somewhere other then with a cell phone, the Copper phone lines or the digital television cable.

The experience I draw upon is the 40 years of living in the boonies, not two miles from town.
We experience at least two power failures a year.   I actually have a gasoline generator for backup power.

Has technology improved in the past 40 years?  NO! - as a matter of fact, it has gotten worse - in my opinion.

The past couple of storms, Hurricane Sandy in particular has taught me one thing, do not rely on the phone company or the electric company for anything!

Because so much of what we rely on has been taken off the copper phone lines and has been transferred to the cell phones, the phone company is reluctant to do any type of maintenance or repairs to any of the phone lines.   In a one month period I was without a telephone for three weeks.
Although the phone company - VERIZON knew there was a problem with the line, their new policy is NOT to fix ANYTHING without a complaint and a work order.
They can physically see the broken line hanging over the road, and will do nothing about it unless someone complains.

In several areas, the trees has fallen over the trunk lines and nothing has been done about it.
The main phone cable has been stretched, pulled off the pole and is only 3 feet off the ground and no one will cut the tree or fix the line.   The mass exodus from the home phone and to a bundled service with the cable company has lead them to not care anymore and to actually encourage YOU to migrate to the cell phones - which is where the phone company and the government would like for you to be anyways.

The second option - the cable company, has lines going through the town and a green box connected to the power utility pole about every 500 yards - must be some type of amplifier.
When the power goes out, so does the cable.  No cable, no internet.
Even if the cable company restores the cable service, unless you have electric to your house to the router and your phone - you have no telephone, hence you have no internet...

The third option - not found here is called FIOS - another gimmick.   http://en.wikipedia.org/wiki/Verizon_FiOS
The only thing  good I can say about FIOS is that in Pittsburgh PA they are burying all the FIOS lines. 
That ought to make it a little bit more reliable, but still power dependent.

Because most people do not experience many power outages they think that when the power goes out that nothing else changes, but I can attest to the fact that everything changes when the power goes out for an extended period of time.

If Hurricane Katrina taught us anything, it is that in a disaster you have to expect that everything is going to be dead.  Even if the cell phone tower is still standing and on emergency power, there might not be a backhaul tower to carry the tower information, there is no scheduled fuel delivery so even if it has back up power, when it runs out of fuel, it is going to go offline anyways.  And, if it is the only remaining tower and everyone tries to use it at the same time, it is going to either jam up and fail, or it will get so slow that the only type of communications it will allow will be STM - Simple Text Messaging.

Even at that, the emergency responders are going to be more concerned with helping the people and maintaining order then they are - clearing the roads to get to the cell towers so the tower crews can get fuel to the tower and work on it.  If it is a flood or a tornado and if it involves a bridge washout and no feasible way to replace the bridge, it might take months or even years before they can get to it with a service truck.

Cell towers are a little better then amateur radio and television transmitter towers, that are mainly built in the highest places with little or no concern to accessibility until you can't get to it..
Most cell towers are built right in the residential area to take advantage of as many customers as possible, where as television relies on their antenna transmitting to your antenna.

The World Trade Center was proof that if you put the antenna on top of the tallest building and the building falls down, you have no service of any kind.

At least with HF digital modes, as long as propagation allows it, you can send digital messages to someone that does have internet or phone service or relay a message to someone in the town or area that you are trying to contact.

It isn't going to solve someones lack of connection to Facebook or other social media, but it will allow them to send health and wellnesss traffic so their kinfolk knows that they are alive and ok.

KK0G

Quote from: IT Tech on January 19, 2014, 01:40:44 PM
Re: Low Current Draw Netbook

I will relate some things that I have experienced and maybe you have too...

If I was going to rely on the internet for anything, after a major disaster or apocalypse it would have to happen somewhere other then with a cell phone, the Copper phone lines or the digital television cable.

The experience I draw upon is the 40 years of living in the boonies, not two miles from town.
We experience at least two power failures a year.   I actually have a gasoline generator for backup power.

Has technology improved in the past 40 years?  NO! - as a matter of fact, it has gotten worse - in my opinion.

The past couple of storms, Hurricane Sandy in particular has taught me one thing, do not rely on the phone company or the electric company for anything!

Because so much of what we rely on has been taken off the copper phone lines and has been transferred to the cell phones, the phone company is reluctant to do any type of maintenance or repairs to any of the phone lines.   In a one month period I was without a telephone for three weeks.
Although the phone company - VERIZON knew there was a problem with the line, their new policy is NOT to fix ANYTHING without a complaint and a work order.
They can physically see the broken line hanging over the road, and will do nothing about it unless someone complains.

In several areas, the trees has fallen over the trunk lines and nothing has been done about it.
The main phone cable has been stretched, pulled off the pole and is only 3 feet off the ground and no one will cut the tree or fix the line.   The mass exodus from the home phone and to a bundled service with the cable company has lead them to not care anymore and to actually encourage YOU to migrate to the cell phones - which is where the phone company and the government would like for you to be anyways.

The second option - the cable company, has lines going through the town and a green box connected to the power utility pole about every 500 yards - must be some type of amplifier.
When the power goes out, so does the cable.  No cable, no internet.
Even if the cable company restores the cable service, unless you have electric to your house to the router and your phone - you have no telephone, hence you have no internet...

The third option - not found here is called FIOS - another gimmick.   http://en.wikipedia.org/wiki/Verizon_FiOS
The only thing  good I can say about FIOS is that in Pittsburgh PA they are burying all the FIOS lines. 
That ought to make it a little bit more reliable, but still power dependent.

Because most people do not experience many power outages they think that when the power goes out that nothing else changes, but I can attest to the fact that everything changes when the power goes out for an extended period of time.

If Hurricane Katrina taught us anything, it is that in a disaster you have to expect that everything is going to be dead.  Even if the cell phone tower is still standing and on emergency power, there might not be a backhaul tower to carry the tower information, there is no scheduled fuel delivery so even if it has back up power, when it runs out of fuel, it is going to go offline anyways.  And, if it is the only remaining tower and everyone tries to use it at the same time, it is going to either jam up and fail, or it will get so slow that the only type of communications it will allow will be STM - Simple Text Messaging.

Even at that, the emergency responders are going to be more concerned with helping the people and maintaining order then they are - clearing the roads to get to the cell towers so the tower crews can get fuel to the tower and work on it.  If it is a flood or a tornado and if it involves a bridge washout and no feasible way to replace the bridge, it might take months or even years before they can get to it with a service truck.

Cell towers are a little better then amateur radio and television transmitter towers, that are mainly built in the highest places with little or no concern to accessibility until you can't get to it..
Most cell towers are built right in the residential area to take advantage of as many customers as possible, where as television relies on their antenna transmitting to your antenna.

The World Trade Center was proof that if you put the antenna on top of the tallest building and the building falls down, you have no service of any kind.

At least with HF digital modes, as long as propagation allows it, you can send digital messages to someone that does have internet or phone service or relay a message to someone in the town or area that you are trying to contact.

It isn't going to solve someones lack of connection to Facebook or other social media, but it will allow them to send health and wellnesss traffic so their kinfolk knows that they are alive and ok.

So, do you have any good intel on low power, cheap netbooks?
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

gil

QuoteSo, do you have any good intel on low power, cheap netbooks?

I have heard from more than one source that the Asus EeePC is pretty good on batteries, which would be a major concern for remote operations..

Gil.

KK0G

Quote from: gil on January 19, 2014, 02:14:22 PM
QuoteSo, do you have any good intel on low power, cheap netbooks?

I have heard from more than one source that the Asus EeePC is pretty good on batteries, which would be a major concern for remote operations..

Gil.

I've heard the same thing Gil. They operate on a 12V nominal power supply with minimal current drain and are reported to be excellent quality. I've been keeping an eye out for them on e-Bay.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

White Tiger

Quote from: gil on January 19, 2014, 02:14:22 PM
QuoteSo, do you have any good intel on low power, cheap netbooks?

I have heard from more than one source that the Asus EeePC is pretty good on batteries, which would be a major concern for remote operations..

Gil.

Does anyone know if there is a difference between the Asus eeePC 1000 HE and the HA model?


Sent from my iPad using Tapatalk HD
If you're looking for me, you're probably looking in the wrong place.

raysills

Regarding response #7... (newbie awaiting callsign)... I'm sure the callsign is published now!  Packet radio is legal on almost all ham bands.  The issue is data rate.  Using digital sub-bands elow 28 MHz, current rules only permit 300 baud or less.  Above 28 MHz, 1200 baud may be used.  And, 2 meters is probably the most active packet band, thanks to APRS.  Listen at 144.39 MHz, and you may hear activity in your area.

9600 baud can be used on 2M and above, but that is usually done by direct FSK, rather than the more common AFSK tone mode of packet transmission.

It's also possible to operate some digital modes, like PSK31 and RTTY -without- a computer/tablet/smartphone.  For example, the NUE-PSK modem.  It's an external device that will send and receive PSK31 and RTTY with just a SSB transceiver.  It's -very- low power, and can run nicely with a pair of 9V batteries.  It'll run on 9V, but if you use two batteries, it operates more efficiently, and -both- batteries last longer than a single one used one at a time.  There is even a convenient way to save text received and sent into a USB thumb drive.  But, you'd then need a computer to view the text file.

73 de Ray
K2ULR



madball13


Quote from: White Tiger on January 19, 2014, 07:00:02 PM
Quote from: gil on January 19, 2014, 02:14:22 PM
QuoteSo, do you have any good intel on low power, cheap netbooks?

I have heard from more than one source that the Asus EeePC is pretty good on batteries, which would be a major concern for remote operations..

Gil.

Does anyone know if there is a difference between the Asus eeePC 1000 HE and the HA model?


Sent from my iPad using Tapatalk HD

looks like a better battery

http://www.notebookreview.com/notebookreview/asus-eee-pc-1000he-review/

Blue Rocket

QuoteThe main power hogs on laptops/tablets/etc are the screen and the hard drive.  Obviously, a smaller screen will use less power and I've already mentioned the SSD.  If you could find a computer with an e-ink display, that would use way less power, but I've only seen that on e-readers....probably because the refresh rate is extremely slow and it's black/white only.

Ditto what's been said about SSD and a low res screen (preferably non-touch screen) to save on current draw. I would also like to add the need to run native Windows for ham applications. If your top priority is to minimize current draw, do not utilize virtual machine technology to emulate windows on a Linux or OSX machine. Virtual machine applications are CPU hogs and generate a lot of heat.  If you think about it, you're causing the computer to execute 2X the machine code instructions for your digital radio needs than if you were just running a native version of Windows -- the de facto ham OS. My daily use machine preference for work and play is OSX, but for ham radio its Windows 7.