Jeff - is there any (clever?) way to easily measure decibels of a client bridge?

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Jerry

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Oct 17, 2021, 3:58:01 PM10/17/21
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Jeff - is there any (clever?) way to easily measure decibels of a bridge?
I think only you might know any answer to this question on Android or Win10.

I have all the Android tools to measure signal strength of an access point.
But they don't seem to display the signal strength of the bridge itself.

The client bridge was set up earlier this week using this procedure.
<https://groups.google.com/g/alt.internet.wireless/c/cglQmfONISQ/m/8pzdDv5XAQAJ>

Sitting at the computer (with the client bridge sitting on top of that
desktop) and logging into the Linksys DD-WRT interface shows the Netgear
home router signal is being received by the Linksys WRT56Gv8.1 at around
-50dBm with the displayed "Signal Quality" graph coming out at around 65%.

But how can I _measure_ (easily) the signal the other way around?

Is there an Android or Netgear or Windows tool to measure signal quality of
the Linksys client bridge back at the Netgear WNDR3400v2 home router?

The Netgear Advanced > Administration > Attached Devices doesn't even show
the client bridge. All it shows is the IP (and what I presume is the MAC
address) of the Win10 desktop which is attached to the client bridge.

But what Android or Windows tools tell us the strength of the client bridge?

Jeff Liebermann

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Oct 17, 2021, 4:47:20 PM10/17/21
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On Sun, 17 Oct 2021 12:58:11 -0700, Jerry <Je...@JerryThinks.com>
wrote:

>Jeff - is there any (clever?) way to easily measure decibels of a bridge?

Decibels is a ratio. My guess(tm) is what you want is transmit power
output in dBm (decibels referenced to 1 milliwatt).

>I have all the Android tools to measure signal strength of an access point.
>But they don't seem to display the signal strength of the bridge itself.

Yawn. SSH or telnet to the bridge IP using the the command line
interface (CLI). The wl command should be available:
<https://wiki.dd-wrt.com/wiki/index.php/Wl_command>
Try:
wl cmds
ws assoc or wl status
wl rssi
wl noise
wl channel_qa and wl channel_qa_start

>But what Android or Windows tools tell us the strength of the client bridge?

I think I have a sniffer program for Android that will display signal
level, SNR, data rate, etc in both directions by sniffing the traffic.
Later. I gotta sweep the roof, cover the wood piles, move the
generator, and clean up the mess before it drizzles.

--
Jeff Liebermann je...@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann

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Oct 17, 2021, 4:53:53 PM10/17/21
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On Sun, 17 Oct 2021 12:58:11 -0700, Jerry <Je...@JerryThinks.com>
wrote:
(...)

Also, cease name changing or this will be the last reply you'll get
from me. Pick one name and stay with it.

Jerry

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Oct 17, 2021, 10:35:52 PM10/17/21
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On Sun, 17 Oct 2021 13:47:13 -0700, Jeff Liebermann wrote:

>>Jeff - is there any (clever?) way to easily measure decibels of a bridge?
>
> Decibels is a ratio. My guess(tm) is what you want is transmit power
> output in dBm (decibels referenced to 1 milliwatt).

Luckily the dd-wrt firmware provides what it thinks is the transmit power of
the Linksys WRT54Gv8.1 wireless client bridge at
ddt-wrt:Status > Wireless > Wireless > Wireless Status >
TX Power = 70mW, Rate = 26Mbps

Given this conversion math, would you say the transmit is about -18dBm?
dBm = 10log(mW) = 10log(70) = 18.45 dBm

>>I have all the Android tools to measure signal strength of an access point.
>>But they don't seem to display the signal strength of the bridge itself.
>
> Yawn. SSH or telnet to the bridge IP using the the command line
> interface (CLI). The wl command should be available:
> <https://wiki.dd-wrt.com/wiki/index.php/Wl_command>
> Try:
> wl cmds
> ws assoc or wl status
> wl rssi
> wl noise
> wl channel_qa and wl channel_qa_start

I had to turn on Remote Access at
Administration > Management > Remote Access >
Telnet Management = Enable (it was disabled by default)
Telnet Remote Port = 23

It took me a while to figure out _not_ to use the admin login and password.
Instead, the default _root_ login & password are used when telneting.
C:\> telnet 192.168.1.200
dd-wrt login: root
Password:
==========================================================

____ ___ __ ______ _____ ____ _ _
| _ \| _ \ \ \ / / _ \_ _| __ _|___ \| || |
|| | || ||____\ \ /\ / /| |_) || | \ \ / / __) | || |_
||_| ||_||_____\ V V / | _ < | | \ V / / __/|__ _|
|___/|___/ \_/\_/ |_| \_\|_| \_/ |_____| |_|

DD-WRT v24
http://www.dd-wrt.com

==========================================================
BusyBox v1.9.1 (2008-03-19 20:24:03 CET) built-in shell (ash)
Enter 'help' for a list of built-in commands.
\u@\h:\w\$

\u@\h:\w\$ wl cmds
\u@\h:\w\$ ws assoc
-sh: ws: not found
\u@\h:\w\$ wl status
SSID: "NETGEAR200"
Mode: Managed RSSI: -84 dBm noise: -92 dBm Channel: 3
BSSID: 8C:3B:AD:A6:B2:55 Capability: ESS WEP
Supported Rates: [ 1(b) 2(b) 5.5(b) 6 9 11(b) 12 18 24 36 48 54 ]
\u@\h:\w\$ wl rssi
-82
\u@\h:\w\$ wl noise
-92
\u@\h:\w\$ wl channel_qa
\u@\h:\w\$ wl channel_qa_start
\u@\h:\w\$ help

>>But what Android or Windows tools tell us the strength of the client bridge?
>
> I think I have a sniffer program for Android that will display signal
> level, SNR, data rate, etc in both directions by sniffing the traffic.

The Android sniffer needs to sniff things that aren't set up as an access
point but as a bridge, which is why the three sniffers I tried didn't show
the wireless client bridge traffic - those Android sniffers only showed the
APs of the Netgear home router (AFAICT).
<https://play.google.com/store/search?q=cellular-z>
<https://play.google.com/store/apps/details?id=com.vrem.wifianalyzer>
<https://play.google.com/store/apps/details?id=aws.apps.networkInfoIi>

> Later. I gotta sweep the roof, cover the wood piles, move the
> generator, and clean up the mess before it drizzles.

I hear it's windy up your way.
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