Introduction to Ham Radio: Repeaters (

[@KO4VNX]

My first two weeks as a technician I was using a 'feng radio and didn't realize that I made a mistake in the offset of my local repeater, so I got to hear their nets for two weeks, but I couldn't check-in because nobody could hear me. I finally figured it out and found that my first check-in was very rewarding, after working for two weeks to figure out how to do it! This video would have saved me from two weeks of feeling pretty confused! Great video, perfect for this series!!!

[@KF0NNQ]

Love your videos, Dave. I am a new repeater trustee for my radio club. My repeater is not up and running yet so I can on the ground floor planning and building this repeater. Our club's repeaters are very well used and most operators have no idea of how repeaters actually work. I can't wait to include ASL3. Appreciate you and your videos, 73 Bill, KF0NNQ.

[@ObservaDome]

📻Thanks Dave / Rick KN6UTF📻

[@mattheld5048]

Thanks Dave. I never understood how the radio sends the tone signals. The tones are only, for example, 103 Hz. That is a very low frequency. How can a simple whip antenna on my HT efficiently send such a low frequency? Why use such low frequencies when the radio is optimized to send e.g. 144 MHz?

[@kd4nc]

CTCSS tones are low in frequency specifically so you don’t hear the tone interfering with your transmission… It is very low in the audio passband but it’s a continuous tone and the detection circuit on the receiving end (repeater) is capable of decoding it. The CTCSS tone is injected onto the FM transmitted audio so it’s carried with the RF transmission along with your voice so if your carrier is strong enough the CTCSS is decoded and you get through…. I hope my explanation helps… ‘73’s Doug KD4NC

[@KO4VNX]

as @kdn4nc explains, these tones are "audio" tones, not RF tones. I think of it like this, they are an audio tone (which you don't hear because you are transmitting them, not receiving them) carried over an rf signal. Kind of like tuning my guitar doesn't transmit sound over a radio wave just because I'm playing it, but if I key the mic while playing mu guitar, my audio tone of 82 Hz (an open low E string) can be transmitted on any rf frequency without disturbing other rf signals. And nobody hears these tones because they are received by the repeater, but not repeated on the listening frequency.

[@mattheld5048]

Thanks guys. They are audio tones, not RF. That's the part I misunderstood. Totally clear now.

[@Eric10179]

I’ve noticed a decrease in audio quality recently in the videos. Is it a different mic or maybe some post-production editing?

[@davidhodgson977]

Thank you David, nice explanation to new starters. Good luck to all new radio hams, and welcome to the hobby. I've been doing it for over 40 years, and it never gets boring David HS0ZQA Thailand