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Topic: Atheros AR9580 5GHz tx power

The content of this topic has been archived on 27 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hi there,
I red a little about the ath9k driver and stumbled upon the fact, that there are limits for transmission power.
First, there are limits given by the regdomain and second there are limits given by the regdb.txt.
The limits from the regdb.txt are a little conservative, at least for DE and 5GHz. Setting ATH_USER_REGD=y at least gives one the oppertunity to set tx power for ch 40 to 100mW. According to the regulation for DE and the comments in the regdb.txt the limit for 5150 - 5250 is set a little conservaitive, as TPC in not required. 3dbm would make a big difference for me. Anyhow, i could patch the db, but that wouldn't solve my problem, as there is a hardware limit set.
In theory DE allows up to 1000mW tx power, while for now DFS is not implemented and therefore the limit is 200mW for channel 36 and 40.
I'm using a TP WDR4300 btw, it has that chip.
Now the part I'm not shure about and I wasn't able to find specific information on:
Is the AR9500 capable of transmitting 1000mW? The driver, thankfully supported by Atheros, respects the Hardware values. Also TP-Link ships their router with RegDomain US in EEPROM. I assume the EEPROM also holds the data for the "hardware limits". Following that assumption I suppose I simply could dump the EEPROM, modify the "hardware limit" values and change my RegDomain to DE, recalculate the CRC and flash it back. Obviously I'm not interested in destroing my TX hardware and I would like to follow the approch of using the vanilla ath9k driver.
Does anyone know what the "real" hardware limit is (source would be nice), or if this depends on a seperate piece of hardware (HF amplifier)?

Thank you in advance

Btw, I'm not really interested in hearing about violating laws (I know them, but I don't live in the US) and so on. I know what I do, I have equipment to measure the actual output power.

The FCC OET test reports specify a maximum output power of 433mW for 11a operation and 423mW for 5GHz 11n operation.
Antenna gain is specified with 3dBi for 5GHz.

Source is "Test Report DTS Rev" (No. RF120330C20).
You can find it when searching for Grantee Code: "TE7", Product Code: "WDR4300" on http://transition.fcc.gov/oet/ea/fccid/

Click the detail link on the last search result.
Btw, you can use http://luci.subsignal.org/~jow/reghack/ to lift regulatory txpower limits and channel restrictions.

Hey jow,
thanks for the links, I'll have a look at them.
As I mentioned I would be interested in being able to run vanilla drivers, a binary patcher works but I want "perfection".

The WDR4300 has a maximum transmit power of 18dB.

qasdfdsaq wrote:

The WDR4300 has a maximum transmit power of 18dB.

Hi, do you have a source for that Information?

jow wrote:

The FCC OET test reports specify a maximum output power of 433mW for 11a operation and 423mW for 5GHz 11n operation.
Antenna gain is specified with 3dBi for 5GHz.

Source is "Test Report DTS Rev" (No. RF120330C20).
You can find it when searching for Grantee Code: "TE7", Product Code: "WDR4300" on http://transition.fcc.gov/oet/ea/fccid/

Click the detail link on the last search result.
Btw, you can use http://luci.subsignal.org/~jow/reghack/ to lift regulatory txpower limits and channel restrictions.

And once applied the patch, how can I set the new channels ?? Just through the uci interface like this uci set wireless.radio1.channel=x?

Thanks

(Last edited by ndarkness on 26 Feb 2013, 17:15)

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