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Audio latency issues in remote stations.

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Richard-3

Audio latency issues in remote stations.

I've been watching the discussions related to remote stations, and
discussions related to latency. Has anyone compared the latencies of
various setups. I think I understand that there is latency within a
station (equipment) whether local or remote, and a latency in the
communications lines between the local and remote station. I'm curious
about the local or remote station equipment latency.

Thanks.

--
Richard Hill
NU6T

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Poul Erik Karlshøj (PKA)-2

Re: Audio latency issues in remote stations.

Richard
If you operate CW you also must consider that there will be a contribution to the overall latency from the buffering in the key system. When you use two K1EL Winkeyers connected over IP you have additional latency because the local winkeyer is decided before the character is sent over IP.
Still remote CW works just fine for most QSOs.
Paul/OZ4UN
Sendt fra min iPad

> Den 28/02/2015 kl. 01.55 skrev "Rich" <[hidden email]>:
>
> I've been watching the discussions related to remote stations, and discussions related to latency. Has anyone compared the latencies of various setups. I think I understand that there is latency within a station (equipment) whether local or remote, and a latency in the communications lines between the local and remote station. I'm curious about the local or remote station equipment latency.
>
> Thanks.
>
> --
> Richard Hill
> NU6T
>
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Jim Brown-10

Re: Audio latency issues in remote stations.

On Mon,3/2/2015 4:01 AM, Poul Erik Karlshøj (PKA) wrote:
> If you operate CW you also must consider that there will be a contribution to the overall latency from the buffering in the key system. When you use two K1EL Winkeyers connected over IP you have additional latency because the local winkeyer is decided before the character is sent over IP.

The major contribution to latency is the internet, and it is not constant.

73, Jim K9YC
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John K9UWA-2

Re: Audio latency issues in remote stations.

I would add to Jim's comment that it Varies considerably depending on
YOUR internet connection on both ends. The lousy ISP I am stuck with. Only
Show in Town I get 5M download and 0.3 upload. That is the fastest
available. The Ping Time is inconsistent at 45 ms up to 290 ms. And
sometimes the access to the internet just disappears for 10 to 15 seconds at
a time. Most of you will have access to much better ISP's. My Home ISP
where my station is located ping is consistant at 37ms download rate is
30mb and upload rate is 10mb.
John k9uwa

>
> The major contribution to latency is the internet, and it is not constant.
>
> 73, Jim K9YC

John Goller, K9UWA & Jean Goller, N9PXF
Antique Radio Restorations
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Leo, IN 46765
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1-260-637-6426

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Poul Erik Karlshøj (PKA)-2

Re: Audio latency issues in remote stations.

In reply to this post by Jim Brown-10

Jim you are not correct.
73de OZ4UN
Remote CW since 2005

Sendt fra min iPhone

> Den 02/03/2015 kl. 13.12 skrev Jim Brown <[hidden email]>:
>
>> On Mon,3/2/2015 4:01 AM, Poul Erik Karlshøj (PKA) wrote:
>> If you operate CW you also must consider that there will be a contribution to the overall latency from the buffering in the key system. When you use two K1EL Winkeyers connected over IP you have additional latency because the local winkeyer is decided before the character is sent over IP.
>
> The major contribution to latency is the internet, and it is not constant.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Richard-3

Re: Audio latency issues in remote stations.

In reply to this post by Poul Erik Karlshøj (PKA)-2

Paul, thanks. The latency between the two keyers is a variable
(depending on the locations of the two keyers), but the K1EL keyer
latency should be some standard latency times two. Any idea how much
that standard keyer latency would be?

I'm interested in adding up the latency contribution from the basic
components to understand how each part contributes to the total
latency. I'll initially be most interested in voice, but then in CW and
perhaps eventually in RTTY. This is mostly a thought exercise at the
moment.

There is a kickstarter going for an audio interface with less than 3
millisecond internal latency. It is designed for internet music jam
sessions. My current equipment (including a router) seems to have about
18 ms latency and a total latency between two players seems to need to
be less than about 25-30 ms for two or more to play together across the
internet. So add internet latency and can't play with folks outside the
West Coast. This all got me thinking about remoting radio and whether
there might be a dual use for this "Jam Blaster".

Richard Hill
nu6t

On 3/2/2015 4:01 AM, Poul Erik Karlshøj (PKA) wrote:

> Richard
> If you operate CW you also must consider that there will be a contribution to the overall latency from the buffering in the key system. When you use two K1EL Winkeyers connected over IP you have additional latency because the local winkeyer is decided before the character is sent over IP.
> Still remote CW works just fine for most QSOs.
> Paul/OZ4UN
> Sendt fra min iPad
>
>> Den 28/02/2015 kl. 01.55 skrev "Rich" <[hidden email]>:
>>
>> I've been watching the discussions related to remote stations, and discussions related to latency. Has anyone compared the latencies of various setups. I think I understand that there is latency within a station (equipment) whether local or remote, and a latency in the communications lines between the local and remote station. I'm curious about the local or remote station equipment latency.
>>
>> Thanks.
>>
>> --
>> Richard Hill
>> NU6T
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]

Poul Erik Karlshøj (PKA)-2

Re: Audio latency issues in remote stations. Specific for CW.

Richard

This is only of interest to CW operators.

The latency (the time from when you send a character from Your paddle to the local PC until the remote rig starts to transmit this character) will be about half a second (500 milliseconds!) plus the internet delay. My understanding is that this delay at least partly is caused by the decoding of the paddle input. I did not measure this but I have used two connected Winkeyers for some time and that is my experience.

When you use the keyboard as an input to the local winkeyer it corresponds to using a paddle input with very fast keying. In both cases (paddle or keyboard) you can input so fast that you constantly are a little ahead of the transmitted stream. That in fact is necessary for perfect CW. Therefore, break-in CW is a little easier using the keyboard rather than the paddle. However this only applies to a system based on local decoding (Winkeyer). The Remoterig system may be better in this respect- I have no experience with Remoterig.

Of course if you have a poor internet quality (high latency or high jitter) this might be the limiting factor. Remote operation is no fun with bad internet quality! But you can definitely make fine CW QSOs even over a satellite link (ping time 600 msec). High latency is not too much of a problem - you can get used to it (in my view after using remote CW for ten years). But high jitter is a PITA.

If you have a good internet quality (say latency around 30-50 msec) you will feel annoyed by the "buffer" latency, especially if you try to operate break-in using paddles. You will need to be prepared to stop transmission (cursor placed over the stop button in the Winkeyer window ready for you to left-click in order to stop immediately). This IS possible but NOT easy to do.

Sendt fra min iPad

> Den 02/03/2015 kl. 18.50 skrev "Rich" <[hidden email]>:
>
> Paul, thanks. The latency between the two keyers is a variable (depending on the locations of the two keyers), but the K1EL keyer latency should be some standard latency times two. Any idea how much that standard keyer latency would be?
>
> I'm interested in adding up the latency contribution from the basic components to understand how each part contributes to the total latency. I'll initially be most interested in voice, but then in CW and perhaps eventually in RTTY. This is mostly a thought exercise at the moment.
>
> There is a kickstarter going for an audio interface with less than 3 millisecond internal latency. It is designed for internet music jam sessions. My current equipment (including a router) seems to have about 18 ms latency and a total latency between two players seems to need to be less than about 25-30 ms for two or more to play together across the internet. So add internet latency and can't play with folks outside the West Coast. This all got me thinking about remoting radio and whether there might be a dual use for this "Jam Blaster".
>
> Richard Hill
> nu6t
>
>> On 3/2/2015 4:01 AM, Poul Erik Karlshøj (PKA) wrote:
>> Richard
>> If you operate CW you also must consider that there will be a contribution to the overall latency from the buffering in the key system. When you use two K1EL Winkeyers connected over IP you have additional latency because the local winkeyer is decided before the character is sent over IP.
>> Still remote CW works just fine for most QSOs.
>> Paul/OZ4UN
>> Sendt fra min iPad
>>
>>> Den 28/02/2015 kl. 01.55 skrev "Rich" <[hidden email]>:
>>>
>>> I've been watching the discussions related to remote stations, and discussions related to latency. Has anyone compared the latencies of various setups. I think I understand that there is latency within a station (equipment) whether local or remote, and a latency in the communications lines between the local and remote station. I'm curious about the local or remote station equipment latency.
>>>
>>> Thanks.
>>>
>>> --
>>> Richard Hill
>>> NU6T
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>