Thanks starcms.
I looked at the source code for reghack (http://luci.subsignal.org/~jow/reghack/) and looks like I only need to change these two lines replacing 30 to 4:
struct ieee80211_reg_rule r2 = REG_RULE(2400, 2483, 40, 0, 30, 0);
struct ieee80211_reg_rule r5 = REG_RULE(5140, 5860, 160, 0, 30, 0);and recompile an arm version to patch the powertable without recompiling cfg80211.ko
Or you could just apply the reghack2 file I had mentioned earlier in the thread (which is already compiled to work with the wrt1200/1900 series; you could apply it to the 3200, as well as the 1200AC V2 and 1900ACS V2 also but it wouldn't do anything), and then you can change the transmit power level to anything you want (from 4 to 30 dBm). It would work perfectly on your WRT1900AC V1 (mamba).
The only reason you are having difficulty changing the power level as-is is because I never noticed that in the power table, the values for the mamba (WRT1900AC V1) are more restricted than those of the WRT1900AC V2, WRT1900ACS V1, and WRT1200AC V1 (the models which read the power table from firmware, not eeprom). Applying reghack2 the way it is would fix that on the WRT1900AC V1.
So there's really 3 cases your router can fall under, not 2 as previously thought:
a) 1900AC V1: all by itself. It has a restricted power table which doesn't allow changing of transmit power level, but it is in firmware and can be modified and reghack2 will do so and work just fine. Can be modified by other means also.
b) 1900AC V2, 1900ACS V1, 1200AC V1: has a power table that allows the transmit power and country code to be modified. Power table is in firmware and can be modified further using reghack2 or other means.
c) 1200AC V2, 1900ACS V2, and 3200ACM: power table is in eeprom and you can't modify anything, period.
Edit: Also, reghack doesn't simply change the two lines to:
struct ieee80211_reg_rule r2 = REG_RULE(2400, 2483, 40, 0, 30, 0);
struct ieee80211_reg_rule r5 = REG_RULE(5140, 5860, 160, 0, 30, 0);
it also removes any other restrictions preventing you from lowering the transmit power. So if you just apply it the way it is, it will allow you to change the transmit power from 4dBm to 30dBm on any channel and negate the limited power table on your mamba.
(Last edited by starcms on 11 Aug 2017, 23:46)