Author Topic: Optimum setting when Using Cell Phone Hot Spot  (Read 619 times)

kw7y

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Optimum setting when Using Cell Phone Hot Spot
« on: 2021-08-24, 01:38:59 »
I would be interested to know what CODEC, RX Jitter buffer, RX Jitter delay and Audio Packet size you are using for acceptable audio quality and minimal dropouts when connecting the RRC Control unit to the internet via a cell phone hot spot.

Thanks

- Paul

dj0qn

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Re: Optimum setting when Using Cell Phone Hot Spot
« Reply #1 on: 2021-08-24, 11:31:37 »
Paul,

For any low-bandwidth situation, I suggest the following from my low bandwidth checklist:

Try reducing your bandwidth to a minimum and changing some parameters to compensate for a poor line. Note that this is only for using 3G/4G on the control side. Running a RemoteRig system over 3G/4G with the router on the radio side will never work, unless you pay extra for a true external IPv4 address.

Here are some tips:

1) These are important:
- audio quality to 0 (half the bandwidth of codec 2 and more than adequate for SSB & CW)
- If using the K3 Twin or Yaesu with a second receiver, then turn off "audio dual-rx" on the radio RRC under the radio settings. This doubles the necessary bandwidth if on.

2) Play around with these 3 until you are satisfied:
- increase rx jitter buffer to min 12+
- increase rx jitter delay to min 10+
- audio packet size 20 or 40

Even though this increases data, I suggest setting RTP to continuous, since this forces a consistent data stream and may make the connection more stable.

73,
Mitch DJ0QN / K7DX

oh1jd

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Re: Optimum setting when Using Cell Phone Hot Spot
« Reply #2 on: 2021-09-14, 17:09:39 »
I am a bit puzzled with the jitter and delay settings on bad lines as it seems that sometimes the lower jitter and delay value works much better than the larger ones.

First of all, the configuration
Radio side) Finland - 4g-router with a good continuous stream of 20 mbit/s with low jitter and delay to practically anywhere
Control side) China, Shanghai - fiber  with a good continuous stream of at least 20 mbit/s with ping to the station about 350 ms but jitter reading hovering between 5 ms to 1000 ms.

It looks like uplink (outgoing audio from shanghai) is flawless. What happens is that on the reception, there are occasional cuts. It looks as if the best setting at the control end is Jitter 14 delay 10. Anything beyond or below is worse. Been trying to understand why, but so far haven't found a logical explanation why would it be this way.

Any ideas ?

Ville oh1jd