Hi Rob I missed your followup and tested the 'revert.diff' patch, attached for reference. I have been slow replying because I've been scratching my head over the results. I used 'signaltest.pl' to test[1], which uses tzap under the hood. Perhaps this is not the best choice, but I wanted something that I thought would allow objective comparisons. That's trickier than I thought... Unfortunately I only discovered last night how easy 'vlc ./channels.conf' makes doing quick visual checks. I didn't have enough time to re-patch and test again. My test procedure was: - get a baseline with tzap and signaltest.pl - patch, make, install. cold boot. - test with tzap and signaltest.pl - revert patch, for the moment. I tested two kernels, and both cards. I tested all the tuners but I'll spare you that for now. * 2.6.24-23-rt + v4l (c57f47cfb0e8+ tip) I got rather different baseline results. All channels had significantly higher BER than I'd noticed before. After patching, snr on some channels seemed a little higher and BER was lower. On ch9, I think snr was up and BER improved a little. here are the signaltest summary tables: without patch. usb device (dvb0) usbid db78:0fe9 Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 76.0 % 322.6 672.4 Seven 191625000 76.0 % 320.2 1783.3 Nine 219500000 76.8 % 329.8 2948.2 Ten 226500000 76.9 % 296.6 4885.0 ABC 571500000 77.0 % 542.0 7529.4 SBS 578500000 77.1 % 539.5 10669.7 D44 with patch. usb device (dvb0) usbid db78:0fe9 Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 76.6 % 2.3 0.0 191625000 77.0 % 235.5 83.3 219500000 76.9 % 288.0 501.8 226500000 76.9 % 295.1 1416.4 571500000 77.0 % 523.4 3980.0 578500000 77.1 % 549.9 7409.4 without patch. pcie device (dvb1) pciid db78:18ac Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 71.2 % 3.1 0.0 191625000 21.7 % 645.4 246.4 219500000 73.6 % 1.9 1632.0 226500000 73.5 % 2.8 1632.0 571500000 73.9 % 13.6 2134.6 578500000 72.7 % 58.2 6393.4 with patch. pcie device (dvb1) pciid db78:18ac Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 73.2 % 4.0 0.0 191625000 74.0 % 37.0 0.0 219500000 73.9 % 0.0 0.0 226500000 73.0 % 4.6 0.0 571500000 74.2 % 76.7 193.6 578500000 72.8 % 213.8 4480.3 * 2.6.31-14-generic + v4l (19c0469c02c3+ tip) Hard to say if I'm seeing an improvement. before patching - adapter0 usbid db78:0fe9 Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 75.5 % 293.7 1926.4 191625000 75.9 % 363.2 2993.3 219500000 76.7 % 304.5 4225.8 226500000 76.9 % 223.8 6153.3 571500000 77.0 % 491.7 8726.0 578500000 77.1 % 558.9 11787.1 adapter0 repeat usbid db78:0fe9 (not sure what happened to UNC here..) Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 75.9 % 327.9 13893.6 191625000 76.0 % 392.8 14939.0 219500000 76.7 % 252.0 16052.0 226500000 76.8 % 254.0 18063.1 571500000 76.9 % 533.2 20644.1 578500000 76.9 % 464.1 23836.8 after patching - adapter0 usbid db78:0fe9 Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 76.3 % 2.5 0.0 191625000 76.8 % 227.6 119.0 219500000 76.8 % 262.6 604.5 226500000 76.8 % 282.7 1545.4 571500000 77.0 % 486.8 3541.7 578500000 77.1 % 521.5 6537.7 before patching - adapter1 pciid db78:18ac Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 70.9 % 0.0 0.0 191625000 69.8 % 2.7 0.0 219500000 73.2 % 4.1 0.0 226500000 73.4 % 4.5 0.0 571500000 74.0 % 0.0 0.0 578500000 72.3 % 125.7 3589.3 after patching - adapter2 pciid db78:18ac (enumeration order changed) Frequency Signal Ber Unc ========= ======== ======== ======== 177500000 73.6 % 0.6 0.0 191625000 74.2 % 0.0 0.0 219500000 74.0 % 4.9 0.0 226500000 73.3 % 163.2 349.7 571500000 74.4 % 267.0 1014.6 578500000 72.7 % 70.7 4906.0 Thoughts? What's your test procedure? Cheers Vince [1] http://linuxtv.org/wiki/index.php/Testing_reception_quality
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revert.diff
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