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TXPower increase?

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I was just checking out the txpower of the radio's on the Nano. I saw that one of them is running at 18dbi, which is a little low for my liking.

"iw reg get" told me my max allowed txpower is 30dbi.

So i did,
ifconfig wlan0 down

iwconfig wlan0 txpower 20

ifconfig wlan0 up

and then iwconfig to check txpower. It was still at 18dbi.

Now i have just gone through the process of upping my Kali install's txpower and it was a mission and a half. I was really hoping the Pineapple would do it the easy way!

I also tried the "iw phy phy1 set txpower fixed 20" But this also failed.

So what can i do? Im in a country that allows me to ramp this up, so im not doing anything naughty here.

p.s On a side note ... i recently purchased 2 wifi antenna's. 1 claiming to be 7dbi, and the other 9dbi. I already own a 2dbi one. And the antenna that gets me the best distance is the 2dbi antenna. And yes i mean in a straight line, perfectly in the radiation pattern of the higher dbi antenna's. I got them from ebay and it made me wonder ... It's pretty damn easy to say an antenna is 9dbi when it's actually 2dbi. I mean who can actually check? I'm thinking my antenna's are possibly fakes?

Edited by reed00112

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I haven't checked but I'm sure the regulatory domain for the pineapple is set to the us. So I'd assume if you're doing this from ssh to the pineapple you'd need to do an iw reg set <country code> could be wrong just guessing.

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I'm pretty sure the radios on the NANO are locked.

I find that a bit weird really. You'd think that a device like the Pineapple would have functionality for something so fundemental to it's core purpose.

I'm gonna get a highly directional antenna, hopefully one that is actually the dbi it specifies.

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TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

There's a lot of myth and legend surrounding txpower, mostly because improperly configured systems would let you set the txpower as high as the config file would allow -- but not actually do anything. So while you can sometimes issue a command to set txpower to 30 and the system will report back 30, it won't actually do anything on the radio side. No special command is going to push the silicon to output more than it's made to, regardless of what the OS says -- and that goes for any system.

Here's how it actually works:

You start with a radio SoC. In our case chain0 is AR9331 and chain1 is AR9271. Actual silicon is typically between 16-22 dBm depending on mode. (HT40 for instance, while twice the bandwidth, typically sees lower output power than HT20). The txpower reported by the OS is determined by a special partition which is written to when the board is calibrated at the factory. This calibration is essential to the sensitivity, reliability and overall effectiveness of the device since no two things in the universe are 100% identical. #physics. What you end up with is the output power in dBm.

Then you have the antenna, which is rated in dBi gain. The NANO ships with small 2 dBi gain antennas -- though we will soon offer a pair of 5 dBi gain antennas specially fit for the tactical case. The more gain, the higher the total output power.

When you add the two values -- the dBm output and dBi gain, you get your total output power in dBm. It's often called EIRP. For the NANO that's 20 and 22 dBm. A watt calculator will tell you that a stock NANO can output some 158 mW while an upgraded 5 dBi antenna brings it to 316 mW and a 9 dBi will get you to 800 mW.

If you want to increase the output power further, you'll need an amplifier. These are large and expensive, but when paired with the right transmitter and antenna can greatly improve performance. We have four skybridge amps built into the TETRA -- which constitute nearly 50% of its mass and at least half of the power budget. For them to work efficiently they need to be tuned and they'll want a relatively lower input power. It's sorta like how you don't want your iPod cranked to max volume when you plug it into your car stereo.

The NANOs size, cost and power budget couldn't warrant such onboard amplifiers, but that's not to say you can't use one downstream. It's just a matter of plugging in and powering on. The ALFA booster in the HakShop will up the NANO output to 27 dBm (500 mW) or 29 dBm (800 mW). The later with a 9 dBi antenna will do 6.3 Watt and the former with a 15 dBi antenna will do 16 Watt -- both legally.

Here's some further reading: http://www.cpcstech.com/dbm-to-watt-conversion-information.htm

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Thanks DK for the primer on RF transmission! I recall you going through a lot of those points on an episode of hak5, but it sure is nice to have it boiled down so succinctly here. Plus it makes me even more excited to get my TETRA on! Cheers!

telot

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TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

There's a lot of myth and legend surrounding txpower, mostly because improperly configured systems would let you set the txpower as high as the config file would allow -- but not actually do anything. So while you can sometimes issue a command to set txpower to 30 and the system will report back 30, it won't actually do anything on the radio side. No special command is going to push the silicon to output more than it's made to, regardless of what the OS says -- and that goes for any system.

Here's how it actually works:

You start with a radio SoC. In our case chain0 is AR9331 and chain1 is AR9271. Actual silicon is typically between 16-22 dBm depending on mode. (HT40 for instance, while twice the bandwidth, typically sees lower output power than HT20). The txpower reported by the OS is determined by a special partition which is written to when the board is calibrated at the factory. This calibration is essential to the sensitivity, reliability and overall effectiveness of the device since no two things in the universe are 100% identical. #physics. What you end up with is the output power in dBm.

Then you have the antenna, which is rated in dBi gain. The NANO ships with small 2 dBi gain antennas -- though we will soon offer a pair of 5 dBi gain antennas specially fit for the tactical case. The more gain, the higher the total output power.

When you add the two values -- the dBm output and dBi gain, you get your total output power in dBm. It's often called EIRP. For the NANO that's 20 and 22 dBm. A watt calculator will tell you that a stock NANO can output some 158 mW while an upgraded 5 dBi antenna brings it to 316 mW and a 9 dBi will get you to 800 mW.

If you want to increase the output power further, you'll need an amplifier. These are large and expensive, but when paired with the right transmitter and antenna can greatly improve performance. We have four skybridge amps built into the TETRA -- which constitute nearly 50% of its mass and at least half of the power budget. For them to work efficiently they need to be tuned and they'll want a relatively lower input power. It's sorta like how you don't want your iPod cranked to max volume when you plug it into your car stereo.

The NANOs size, cost and power budget couldn't warrant such onboard amplifiers, but that's not to say you can't use one downstream. It's just a matter of plugging in and powering on. The ALFA booster in the HakShop will up the NANO output to 27 dBm (500 mW) or 29 dBm (800 mW). The later with a 9 dBi antenna will do 6.3 Watt and the former with a 15 dBi antenna will do 16 Watt -- both legally.

Here's some further reading: http://www.cpcstech.com/dbm-to-watt-conversion-information.htm

I just bought 2 of the AWUS036NEH off the hakshop for some RPi work I'm doing but I commandeered the 5dBi antennas for my Nano :P

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TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

EDITED FOR SPACE

Hi Darren,

I saw in the latest video the nice setup with the amps,

I have a couple of questions,

1. Do they require separate USB power (meaning 2 PineApple Juices) one for the Nano and another for the Amps or is the power from the Nano enough to power 2 Amps and the Nano?

2. Can you do a screen grab of the extra AccessPoints and also TX if possible with and without those installed.

3. Lastly do you have 8Dbi antenna for sale?, I can see any if you do

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Would this stop me from dropping the tx power to a lower level as well?

I tried setting wlan1 to 19dBi, and it doesn't seem to be doing anything. Which is weird because it works on my other devices, and I'm pretty sure I had gotten it to work on the Mark 5 about a year ago.

What's even weirder is that I plugged in the Alfa AWUS036NEH with a 9dBi antenna to test it, and by default I'm given a txpower of 30 which isn't even a legal amount. Luckily I don't plan on using the NEH with the nano so it's not much of a problem for me personally, but I wonder if there are others out there accidentally breaking the law.

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TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

Which antenna (close to USB male end or female end) would the booster work better on?

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Which antenna (close to USB male end or female end) would the booster work better on?

Depends on which antenna you want to be stronger. The side with SD card and the vents is WLAN1(Male end). This is the antenna that does recon scanning and enters monitor mode. The other antenna is WLAN0; this handles hosting the APs that clients connect to and also hosts the management network (WLAN0-1).

Edited by audibleblink

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With one amp it makes the most sense to put it on the wlan0 side. With two amps it makes sense for both, obviously. Under normal circumstances it doesn't make sense to only have one amp on the wlan1 side since you'll be advertising SSIDs to devices further away than the wlan0 AP radio can respond to.

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On 1/19/2016 at 5:55 PM, Darren Kitchen said:

TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

There's a lot of myth and legend surrounding txpower, mostly because improperly configured systems would let you set the txpower as high as the config file would allow -- but not actually do anything. So while you can sometimes issue a command to set txpower to 30 and the system will report back 30, it won't actually do anything on the radio side. No special command is going to push the silicon to output more than it's made to, regardless of what the OS says -- and that goes for any system.

Here's how it actually works:

You start with a radio SoC. In our case chain0 is AR9331 and chain1 is AR9271. Actual silicon is typically between 16-22 dBm depending on mode. (HT40 for instance, while twice the bandwidth, typically sees lower output power than HT20). The txpower reported by the OS is determined by a special partition which is written to when the board is calibrated at the factory. This calibration is essential to the sensitivity, reliability and overall effectiveness of the device since no two things in the universe are 100% identical. #physics. What you end up with is the output power in dBm.

Then you have the antenna, which is rated in dBi gain. The NANO ships with small 2 dBi gain antennas -- though we will soon offer a pair of 5 dBi gain antennas specially fit for the tactical case. The more gain, the higher the total output power.

When you add the two values -- the dBm output and dBi gain, you get your total output power in dBm. It's often called EIRP. For the NANO that's 20 and 22 dBm. A watt calculator will tell you that a stock NANO can output some 158 mW while an upgraded 5 dBi antenna brings it to 316 mW and a 9 dBi will get you to 800 mW.

If you want to increase the output power further, you'll need an amplifier. These are large and expensive, but when paired with the right transmitter and antenna can greatly improve performance. We have four skybridge amps built into the TETRA -- which constitute nearly 50% of its mass and at least half of the power budget. For them to work efficiently they need to be tuned and they'll want a relatively lower input power. It's sorta like how you don't want your iPod cranked to max volume when you plug it into your car stereo.

The NANOs size, cost and power budget couldn't warrant such onboard amplifiers, but that's not to say you can't use one downstream. It's just a matter of plugging in and powering on. The ALFA booster in the HakShop will up the NANO output to 27 dBm (500 mW) or 29 dBm (800 mW). The later with a 9 dBi antenna will do 6.3 Watt and the former with a 15 dBi antenna will do 16 Watt -- both legally.

Here's some further reading: http://www.cpcstech.com/dbm-to-watt-conversion-information.htm

Very well said, thank you for the detailed explanation ... even being in the RF field for 10+ years it's hard to convince some people about this.

On 1/19/2016 at 11:23 AM, reed00112 said:

I was just checking out the txpower of the radio's on the Nano. I saw that one of them is running at 18dbi, which is a little low for my liking.

"iw reg get" told me my max allowed txpower is 30dbi.

So i did,
ifconfig wlan0 down

iwconfig wlan0 txpower 20

ifconfig wlan0 up

and then iwconfig to check txpower. It was still at 18dbi.

Now i have just gone through the process of upping my Kali install's txpower and it was a mission and a half. I was really hoping the Pineapple would do it the easy way!

I also tried the "iw phy phy1 set txpower fixed 20" But this also failed.

So what can i do? Im in a country that allows me to ramp this up, so im not doing anything naughty here.

p.s On a side note ... i recently purchased 2 wifi antenna's. 1 claiming to be 7dbi, and the other 9dbi. I already own a 2dbi one. And the antenna that gets me the best distance is the 2dbi antenna. And yes i mean in a straight line, perfectly in the radiation pattern of the higher dbi antenna's. I got them from ebay and it made me wonder ... It's pretty damn easy to say an antenna is 9dbi when it's actually 2dbi. I mean who can actually check? I'm thinking my antenna's are possibly fakes?

The value you're going to see when running `iw reg get` is based on the regulatory domain, for the max you would be allowed to set ... doesn't necessarily mean that will work.  

This is a little out-dated, but has good information on an old homebrew tester: 
http://pe2er.nl/wifiswr/

Here's a good video with Darren explaining dbm, dbi, and eirp:

 

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On 1/19/2016 at 11:55 PM, Darren Kitchen said:

TL;DR: The NANO isn't txpower locked -- they're capped the chips maximum which is what we've implemented. No magic command is going to push the silicon past its spec. The easy way to increase total output power is with a higher gain antenna. If you want to take it a step further, I recommend using a low noise amplifier like the USB powered ALFA booster in the hakshop.

There's a lot of myth and legend surrounding txpower, mostly because improperly configured systems would let you set the txpower as high as the config file would allow -- but not actually do anything. So while you can sometimes issue a command to set txpower to 30 and the system will report back 30, it won't actually do anything on the radio side. No special command is going to push the silicon to output more than it's made to, regardless of what the OS says -- and that goes for any system.

Here's how it actually works:

You start with a radio SoC. In our case chain0 is AR9331 and chain1 is AR9271. Actual silicon is typically between 16-22 dBm depending on mode. (HT40 for instance, while twice the bandwidth, typically sees lower output power than HT20). The txpower reported by the OS is determined by a special partition which is written to when the board is calibrated at the factory. This calibration is essential to the sensitivity, reliability and overall effectiveness of the device since no two things in the universe are 100% identical. #physics. What you end up with is the output power in dBm.

Then you have the antenna, which is rated in dBi gain. The NANO ships with small 2 dBi gain antennas -- though we will soon offer a pair of 5 dBi gain antennas specially fit for the tactical case. The more gain, the higher the total output power.

When you add the two values -- the dBm output and dBi gain, you get your total output power in dBm. It's often called EIRP. For the NANO that's 20 and 22 dBm. A watt calculator will tell you that a stock NANO can output some 158 mW while an upgraded 5 dBi antenna brings it to 316 mW and a 9 dBi will get you to 800 mW.

If you want to increase the output power further, you'll need an amplifier. These are large and expensive, but when paired with the right transmitter and antenna can greatly improve performance. We have four skybridge amps built into the TETRA -- which constitute nearly 50% of its mass and at least half of the power budget. For them to work efficiently they need to be tuned and they'll want a relatively lower input power. It's sorta like how you don't want your iPod cranked to max volume when you plug it into your car stereo.

The NANOs size, cost and power budget couldn't warrant such onboard amplifiers, but that's not to say you can't use one downstream. It's just a matter of plugging in and powering on. The ALFA booster in the HakShop will up the NANO output to 27 dBm (500 mW) or 29 dBm (800 mW). The later with a 9 dBi antenna will do 6.3 Watt and the former with a 15 dBi antenna will do 16 Watt -- both legally.

Here's some further reading: http://www.cpcstech.com/dbm-to-watt-conversion-information.htm

I have the TETRA device and I want to get the maximum txpower. I set US on the configuration and I have 30 dBm on txpower. I have been changing the tx power on /etc/conffig/wireless file and I have analyzed the emision power. I only could set 30dBm or less. This is the limit existent on TETRA? Is it possible amplify it?

Thanks!

Edited by Hackituria
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