New Ringo, got some questions

hi there, i just put my Ringo together yesterday afternoon & i have some questions.

  1. Whenever the screen / backlight is on I can hear a very faint super-high-pitched whining sound. I don’t even hafta bring the phone up to my ear, i can hear the sound with the phone on my desk infront of me. Does the backlight use a highfrequency driver? is it like an EL thing maybe?
    (edited to add: the whine goes away with backlight at Max but its back on any other dimmer setting! maybe the backlighting is dimmed with PWM and i’m hearing the frequency of that?)

  2. I can send SMS texts ok from Ringo but received texts come up as all asterisks. Like I send ‘Test’ from another phone and receive ‘****’ on the Ringo. The sending phone number comes up ok tho. Does that indicate a corrupted SD card? I’ve been lurking on here for a week & saw a few things where a borked SD card can lead to wierd results.

  3. LED brightness in settings doesn’t seem to be saved? or maybe it’s saved but when you use the Flashlight app that breaks it? Every time I look in settings the LED brightness is back at maximum & i keep setting it to like lower.

  4. Is there any way (other than recompiling the firmware) to change the colour of the LEDs when you unlock the phone? Like they always do the thing in red, I’d like it a different colour. If it could use the flashlight colour that’d be nice.

  5. With all those LEDs on there I thought maybe they’d light up when the phone rang or you got a text! I figure like (4) this is something I’d hafta change in firmware if I wanted to make it happen?

  6. My Ringo has the SIM7600A-H module on it. Is there any advantage to adding a 2nd antenna to the Aux jack? (I have another quad-band cellular antenna here with the right connector.)

  7. Are there any ‘Getting Started’ guides for compiling the firmware that work on Mac or Linux? I don’t have access to a windows computer, just mac & linux here.

Thank you! ^^

so heres what i have learned in 2 days

  1. the schematics dont’ show any kind of EL driver on the display board or main board, but i think the display panel uses LED backlights. i think the highpitched noise i’m hearing is coming from T1 on the display board maybe? the pitch doesn’t really change with the brightness but something about the sound changes. i think its the PWM frequency i’m hearing and thats probably not something that can be changed.

  2. i have reformatted the SD card with no change, incoming SMS messages all show teh content as **********

  3. while i was playing with the SD card I looked in the settings.json and there is no saved value for LED brightness, so i conclude it is not saved

  1. eventually i’ll get around to experimenting with antennas & see what happens. i also have a little gps antenna thats designed for these modules & gonna see how that works too

(i had to leave those blank #s or it would change my #6 to a #4 :pouting_cat:)

if anyone has feedback on the other points i’d appreciate it

I have a similar problem with asterisks in incoming SMS messages. If I send a text from my everyday Samsung smartphone I get the message ok, but when I try to set up service with a service provider (EE) all their texts to me appear as asterisks, so I can get no further. Obviously, I can’t make phone calls on the Ringo yet, but I can receive voice calls on the Ringo perfectly well.

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oh thats interesting that you get messages ok from your regular phone! i get the asterisks when i test from my regular phone (iphone) but i havent been able to test any other incoming texts.

i did try a ussd code and it sent ok but the incoming message from the carrier was gibberish.

btw are you a amature radio operater? g3wzk sounds like a callsign. we’re va3uxb but we havent been active for a few years.

Interesting! I may try a SIM card from another provider to see if that makes any difference. Yes, I have held my amateur radio licence for 53 years now - was at school when I first started. Now retired and enjoying my hobbies again. My wife has her hobbies too so we are both happily occupied despite lockdown etc!

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trying another sim is a good idea. i’ll hafta see if we can get another pay-as-you-go for cheap around here & try it out.

the sim we have in our Ringo atm is a pay-as-you-go from a budget operater but they sublet from one of the big 3 in canada so it should be ‘as good as’. and we’ve used this sim in like a dozen other phones without any trouble over the years so we know its not the sim or the service provider.

So i was reading other forum messages on here & came across one that mentioned incoming texts turning into asterisks:

That makes me wonder if all the texts we’ve received have been unicode. even when we send something like “test” its coming up “***”

wierd thing is we have a homebru PDU decoder we wrote on arduino a few years back, we built a dock (based on an arduino leonardo clone) for an old ericsson t28 and that worked fine for all the texts it received. we actually tested it 2 or 3 weeks ago before we got our ringo & it still worked ok, but maybe the sim7600 is doing stuff that the old ericsson isn’t, idk.

unfortunately we dont really have access to the skills we used to have so idk if we’re capable of debugging/fixing this

its really a killer tho, for us as a 2nd line we want to use it mainly for text messages. we never use it for voice calls.

so i set up another older phone with a paygo sim & the ringo receives texts ok from that phone. just the modern smartphone sending plain text is being received as asterisks, so i figure the modern phone is sending the text as unicode or whatever?
its frustrating cos other old phones receive the texts fine & the arduino thing we played with last week handled it ok. its just something unique to either the SIM7600 or the ringo code.

so i found the solution to my #1 problem - that annoying squealling noise when the LCD backlight is dimmed

i was right about it being the PWM frequency.

in MAKERphone.h line 137 the pwm frequency is set to 5000hz
if i change that to 10000hz i can’t hear it anymore

i tested just using arduino sketches, i sstill hafta figure out how to compile the firmware from source on a mac

but at least i know what to fix when i’m actually able to do that step

Hello again. Just to say that I bought a Vodafone SIM for 99p this week and the Ringo is now working properly. Unfortunately, Vodafone network coverage isn’t very good where we live! I don’t know why there was a problem before, when I was trying to use an EE SIM card. My guess would be that the Ringo has only a limited range of character sets and that SMS messages from EE use a set that the phone doesn’t recognise.