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Daemon · 03-17-2008, 06:13 AM

Attached are some vid caps from the video in the previous post, showing
1, 2 - normal XPS link's effect on video. Typically 1 XPS packet per video frame
3, 4 - XPS Tx retransmit effect on video. Typically 4 XPS packets per video frame
5 - comparison of normal link and retransmit, and where the ACK would normally show in the transmission
6 - Just for grins.. Airtronics FHSS link's effect on video frame. It works the whole 2.4Ghz band so there's a lot of frames with no noise from FHSS signal, but this is what it looks like when it overlaps with the video transmission's channel.

At 30fps, it's roughly 33msper frame of video, while PPM frames are about 20ms, so one
frame of video usually captures about 1.6 PPM frames. It looks pretty chaotic viewed
live, but play it frame by frame, and it's pretty clear.

I don't have a Spektrum or FASST system on hand to show them, but this test isn't exactly
rocket science, if anyone else wants to post up an example.

ian

03-17-2008, 06:13 AM	#169
Daemon Gettin' Lower! Join Date: Feb 2008 Posts: 35	Re: Kiwi's XPS test results are up. Attached are some vid caps from the video in the previous post, showing 1, 2 - normal XPS link's effect on video. Typically 1 XPS packet per video frame 3, 4 - XPS Tx retransmit effect on video. Typically 4 XPS packets per video frame 5 - comparison of normal link and retransmit, and where the ACK would normally show in the transmission 6 - Just for grins.. Airtronics FHSS link's effect on video frame. It works the whole 2.4Ghz band so there's a lot of frames with no noise from FHSS signal, but this is what it looks like when it overlaps with the video transmission's channel. At 30fps, it's roughly 33msper frame of video, while PPM frames are about 20ms, so one frame of video usually captures about 1.6 PPM frames. It looks pretty chaotic viewed live, but play it frame by frame, and it's pretty clear. I don't have a Spektrum or FASST system on hand to show them, but this test isn't exactly rocket science, if anyone else wants to post up an example. ian Attached Thumbnails 50.7 KB · Views: 18 49.9 KB · Views: 11 71.0 KB · Views: 8 73.5 KB · Views: 8 76.1 KB · Views: 18 65.9 KB · Views: 24 Last edited by Daemon; 03-17-2008 at 08:38 PM.