Author Topic: CW problems with dropped or missing characters (resolved)  (Read 4268 times)

N4VT

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Hello all,

After having received some absolutely fantastic help from a couple of folks on the forum here (Mitch - DJ0QN, and Charlie - KB8CR), I was able to get my Remoterig/IC-7100 combo up and running with WiFi on the remote side, and WiFi via iPhone hotspot on the control side.  The only issue that I was not able to get resolved, was dropped/missing characters when using CW (paddle). I assumed it was due to jitter/latency since I was using WiFi at both ends, and because my latency was sometimes 130ms, and jitter sometimes around 60ms. I tried adjusting all of the delays, etc., but with no resolution. My internet speed at the remote side was 8mbps down/.75mbps up, by the way.  In the end, what fixed the problem completely, was a post by AD4ES, who stated that he was able to fix a similar issue by changing the Control RRC to Iambic B from Iambic A. This was an absolute game changer, and finally, it truly is like being in front of my rig at home.  As a note, I use a dual-lever paddle, but I use it as a single-lever paddle, which is to say that I do not use the Iambic technique wherein both paddles are pressed together at times. That said, I have no idea why switching from Iambic A to Iambic B makes a difference, but boy does it ever!

It took a lot of searching to discover this solution, and thankfully AD4ES walked this road before I did and found a solution. I wanted to post this as a thank you to those who’ve helped me, and in the hopes that in so doing, perhaps this particular solution will be easier found by those that may need it. Thanks again to all.

David
N4VT

G3TKF

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Re: CW problems with dropped or missing characters (resolved)
« Reply #1 on: 2018-11-09, 11:06:29 »
Wow ! ... not tried it yet, but that's EXACTLY (even the same radio)the issue I have been getting ever since installing the WiFi unit  - no issues (that anyone can hear) on SSB/FM but CW is jittery and losing packets...
Anyone explain why ?

More when I have changed the settings...

Robin
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G3TKF

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Re: CW problems with dropped or missing characters (resolved)
« Reply #2 on: 2018-11-12, 12:11:48 »
Bad news I'm afraid  :-\
My RRC was set to Iambic A so tried a change to Iambic B ... result - exactly the same issues , same irregular keying and jitter.
Seems several people are having WiFi unit issues elsewhere on the forum.

Any other suggestions re the problem ?

Robin
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dj0qn

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Re: CW problems with dropped or missing characters (resolved)
« Reply #3 on: 2018-11-12, 18:20:46 »
Robin,

Maybe I can help you with some ideas on your WiFi issue:

Basically, one must understand that WiFi is a shared medium and not switched like ethernet. This means that the WiFi
channel that is used to carry your traffic can have lots of QRM that will prevent the continuous stream you are expecting.
When you do have a packet collision, the packet will be resent until confirmed, which is what is causing your problem. This
is unlike UDP over the internet, which is not confirmed and packets are streamed without pause.

Now onto what can be causing this QRM:
- Neighbors sharing the same channel, especially on 2.4 GHz
- Multiple devices in your household using the WiFi at the same time. Worst offenders are streaming and teenagers.
- An older WiFi standard is being used that gives a smaller total bandwidth. Remember that net bandwidth is much less than the spec.
- Other devices such as microwave ovens, some surveillance cameras, etc. also operate on this band
- Etc.

What can be done to solve it, assuming there is no way to lay an ethernet cable:
- Move to a clear channel where no neighbors are operating their router
- Migrate to 5 GHz (you may need a new WiFi Bridge)
- Look for what in your household is causing the interference
- Operate as many devices in your household using ethernet as possible
- Etc.

Can the RRC settings be changed to compensate? The answer is to an extent, but this is a band-aid. Some examples:
- Reduce the audio quality to 0 (half the bandwidth of codec 2 and usually adequate for SSB & CW)
- Turn off dual-receive if used and not needed (halves bandwidth use)
- turn continuous RTP on or set RTP to continuous (depending upon firmware version)
- 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
- Adjust CW settings (you may want to search this Forum for much discussion using the settings below as keywords):
    - Set Lf delay to a higher number
    - Set Key delay to a higher number

I hope this helps.

73,
Mitch DJ0QN / K7DX


G3TKF

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Re: CW problems with dropped or missing characters (resolved)
« Reply #4 on: 2018-11-14, 12:41:58 »
Thanks Mitch
Will try a few of those suggestions

73