ESP8266 Developer Zone

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-22T16:50:17+08:00

PROBLEM SOLVED !!!!

Check this link: https://github.com/espressif/ESP8266_NO ... /issues/85

Statistics: Posted by DreeOlee — Mon Jan 22, 2018 4:50 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-16T05:57:43+08:00

I did a full flash erase, after that, the problem was gone.

So I think the problem is in the API (not accessible software for me) Only if my perspective is well approached, of course.

For my understanding, is this the correct architecture?

---------------
User application
---------------
SDK
---------------
API
---------------
physical layer
---------------

If this is the architecture, than I think the problem is in the API compiled bin files.

Is there someone who can help me with this?

Statistics: Posted by DreeOlee — Tue Jan 16, 2018 5:57 am

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-16T00:24:00+08:00

Just flashed the latest esp_init_data_default.bin but without success.

Is there anyone who can reproduce this problem ?

Statistics: Posted by DreeOlee — Tue Jan 16, 2018 12:24 am

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-13T08:51:16+08:00

Maybe one more idea:
Did you flash the latest esp_init_data_default.bin?
Recently they changed something, so there is a new version "8":
https://github.com/espressif/ESP8266_NO ... master/bin

Statistics: Posted by blubb — Sat Jan 13, 2018 8:51 am

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T23:08:09+08:00

okay thank.....I will place it directly.

Statistics: Posted by DreeOlee — Fri Jan 12, 2018 11:08 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T22:52:11+08:00

I recommend opening an issue on github
https://github.com/espressif/ESP8266_NONOS_SDK/issues

Edit:
There are several APIs like
system_phy_set_powerup_option(...);
system_phy_freq_trace_enable(...);
But if the problem occurs before user_rf_pre_init this is a case for a github issue for sure.

Statistics: Posted by blubb — Fri Jan 12, 2018 10:52 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T22:47:02+08:00

In the user_init. Tried also in the user_rf_pre_init without result.

The problem occurs before the user_rf_pre_init. I commented everything out in the user_rf_pre_init, user_init and the init_done. Strange btw is that after this, I got more debug info on my serial line

Code:

 ets Jan  8 2013,rst cause:2, boot mode:(3,0)

load 0x4010f000, len 1384, room 16 
tail 8
chksum 0x2d
csum 0x2d
v00000000
~ld
rf cal sector: 508
freq trace enable 0
rf[112] : 00
rf[113] : 00
rf[114] : 00

SDK ver: 2.1.0(deb1901) compiled @ Oct 23 2017 17:58:03
phy ver: 1136_0, pp ver: 10.2

mode : null

I still have the problem.

Statistics: Posted by DreeOlee — Fri Jan 12, 2018 10:47 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T18:08:59+08:00

Do you call this API in user_rf_pre_init or in user_init? I wonder if that makes a difference.

Statistics: Posted by blubb — Fri Jan 12, 2018 6:08 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T17:12:54+08:00

Yes I also tried that. In fact, that was our original problem. We made a change in the API and now we had full control over the ESP. But still the problem appears with switching the device on.

It happens only at startup. Just a fraction of time, after that there is no problem. The time is that short, that the spectrum analyzer not always captures the signal.

Statistics: Posted by DreeOlee — Fri Jan 12, 2018 5:12 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-12T07:13:06+08:00

Have you tried the API mentioned here?
viewtopic.php?f=7&t=8768

Statistics: Posted by blubb — Fri Jan 12, 2018 7:13 am

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-11T20:32:50+08:00

I just downloaded the ESP8266_FCC_26m_20170731.bin file, and the result is exactly the same. Directly at power-up and just ones.

Statistics: Posted by DreeOlee — Thu Jan 11, 2018 8:32 pm

Re: FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-11T18:02:37+08:00

Espressif provided an FCC firmware on their website http://www.espressif.com/en/support/download/other-tools.
You can download and test the "ESP8266 Certification and Test".

Statistics: Posted by Her Mary — Thu Jan 11, 2018 6:02 pm

FCC problem - Spectrum analyzer shows unwanted transmission when startup

2018-01-10T21:31:48+08:00

Hello everyone,

This is my first post at this Forum. Hopefully someone can help/support me with this urgent issue.

The problem is that the module shows a lot of unwanted transmissions during start-up, causing the FCC certification to fail.

As the attachment shows, the transmissions are unexpected and not inside the FCC regulations. According the FCC, transmissions outside the blue lines are not allowed.

> I'm using the ESP-WROOM-02 module.
> Latest SDK (also tried previous versions)
> Even deleted every WiFi SDK link, without success
> Try starting up with WiFi disabled, no success
> Tried different power supplies, no success
> The phenomenon is also visible during a restart from deep sleep
> After restart, so from the first line of the initialization/setup(), I have full control without issues.

At this moment I'm out of ideas how to solve this problem. I expect it's a ESP hardware issue, but not sure.

Is there anyone who can help me with this or is there anyone who have seen this problem before?

Greetings,
DreeOlee

Statistics: Posted by DreeOlee — Wed Jan 10, 2018 9:31 pm