[ابو سعد]

اخي فتى الجوف هذه الميزة موجودة في كثير من الاجهزة وتختلف حسب السرعة والحساسية
هذه بعض الروابط اتمنى ان تفيدك

https://www.arrl.org/news/features/1999/0701/1/
https://www.ee.washington.edu/consele...lome/links.htm
https://www.arrl.org/news/features/2003/01/23/1/
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https://www.tech-faq.com/dtmf-tone-frequencies.shtml
https://www.arrl.org/news/enforcement...1999/1026.html
https://www.arrl.org/files/infoserv/qst/qst_indx.90
https://www.arrl.org/FandES/field/reg...s/faq-aux.html
https://en.wikipedia.org/wiki/DTMF
https://www.dsptutor.freeuk.com/dtmf/ToneGenerator.html
https://home.aol.com/pdrunen/
https://www.arrl.org/FandES/tbp/articles/2005/0427/
https://www.arrl.org/members-only/pro.../lab/ft90r.pdf
www.arrl.org/members-only/prodrev/pdf/pr9909.pdf
www.arrl.org/members-only/prodrev/pdf/pr0306.pdf
www.arrl.org/members-only/prodrev/reports.html
www.arrl.org/tis/info/prodrev.html

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