tm506 has no signal

[dark_yami1]

I happens with all sim cards, i looked around on the internet and found that if you flash it with specific Z780i firmware it will give it full signal

TM506 poor signal after unlocking - GSM-Forum

[riders4sia]

I happens with all sim cards, i looked around on the internet and found that if you flash it with specific Z780i firmware it will give it full signal

TM506 poor signal after unlocking - GSM-Forum

that problem came from software itself (i.e. after unlocking) well it can't be the same problem as yours or might be same but you can try what they do, it would be best if you narate the history of your phone, how it came to this problem and so on.