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Justin AB3E's avatar

I'm not sure if it would make sense in the context of 44net, but for tunneling out to other devices from behind CGNAT, I can't recommend Tailscale enough. Looks like it was mentioned in passing in ZR in the past.

It really "Just Works" and has some truly amazing ancillary features like Funnel, Subnet Routers, and Taildrop.

For an interesting use case example, I have an HDHomerun for OTA TV and an rpi 4b on my home network running Tailscale. I can connect my phone to Tailscale and then use VLC to watch streams of OTA TV from anywhere (even over cell networks)

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Alexander, DL4NO's avatar

You should look into the importance of the modulation index for the SNR of FM transmissions. Broadcast FM started with 15 kHz of modulation bandwidth and +/- 75 kHz of frequency deviation which means a modulation index of 5. When introducing stereo, modulation bandwidth increased to 53 kHz and therefore the modulation index was reduced to a bit more than 1. This cost up to 20 dB of SNR, therefore the MONO buttons on many early radios. Narrow FM has a modulation index < 1 which makes voice signals much noisier. Digital transmissions have a very sharp SNR limit where they either work well or not at all.

At least here in EU we switched over the years from 50 kHz (late 1960s) over 25 kHz to 12.5 kHz to get channels for more relays. FM started in ham radio when commercial users switched from 40 kHz to 20 kHz which made the old commercial rigs available for hams. In most of EU 70cm is only 430-440 MHz, while in Scandinavia it is only 432-438 MHz.

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