.. Roofing filter has one BW in CW, another in SSB? 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/mailm
I attempted to measure AM RX audio response with 2.056 a few times, and in all ocassions it was 3 kHz on both main and sub RX. RX filters were fully open and RX was fed from a signal generator having
With V1 firmware the indicated AM bandwidth was that of the recovered audio. With V2 it is the actual IF bandwidth, limited to 6 kHz and preventing any response above 3 kHz, unlike V1. 73, Sinisa YT
It is NOT well as long as AM broadcast audio is limited to 3 kHz. V1 firmware was capable of full 6 kHz AM audio. 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailin
Why? Only to prove that V2.056 can do something albeit half-way? I'd prefer it the way it was done for almost a century, and it worked that way in V1, so it's clearly a degradation. 73, Sinisa YT1NT,
Of course 10 kHz may be too much, but 8 or 9 kHz BW is actually transmitted, and a 3 kHz V2 audio sounds substantially worse than 4 or 4.5 KHz V1 audio. 73, Sinisa YT1NT, VE3EA ______________________
AM demodulation is a nonlinear process and AM BW testing using noise input is meaningless. The filter bandwidth cannot be reliably estimated from the resulting audio spectrum measurements because of
In fact, 14 kHz refers to the IF center frequency, and the sampling rate is 56.09375 kHz. 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailing list TenTec@contesting
The workload is proportional to filter length (199 taps default), and not related directly to the bandwidth. The number of coefficients is most dependent on the required filter slope, measured in dB/
That's incorrect. -33 dB is 2.4 % THD. 0.05 % THD would be -66 dB. 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.cont
The correct formula is: harmonic distortion in % = 100 * (RMS voltage of harmonics) / (RMS voltage of fundamental) It's "total" (THD) if all harmonics are included, otherwise it is "partial". 73, Sin
A fixed width font is recommended to view the data correctly. Part One - Total Harmonic Distortion == Main RX, 3750 kHz, AM PREAMP OFF, ATTN OFF, RF GAIN 100 ROOF 20 kHz, BW 6000 Hz, PBT 0 Hz modulat
Orion I. My impression is that some kind of distortion appears with dynamic signals only, but I was unable to produce it systematically and measure it. 73, Sinisa YT1NT, VE3EA _______________________
A single carrier is not a problem unless it's a very weak signal and both the noise and the signal trigger AGC action. This was discussed earlier. With two or more carriers in the passband, too fast
Part Four - THD & IM with PBT offset == Sub RX, V2.056, 900 kHz, AM BW 6000 Hz, PBT = 2000 Hz HANG 0.3 seconds, 5 dB/s measured at speaker output with external 4 Ohm speaker connected Total Harmonic
NR is an adaptive filter, and adaptive filter IS a filter, its sole purpose being that of bandwidth reduction. What makes is different from "ordinary" filters is the adaptive method of tuning, and n
How quick is "quickly" in real Orion operation? 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/mailman/l
MDS, S/N and similar measurements with NR on must be peformed completely with the signal present, and not by switching the signal on and off. If the signal goes off, NR would readapt, so the sytem be
Orion I Noise Reduction Testing == Tested with NR settings of 1 and 9, firmware V1.373b5. Testing performed in LSB mode, PBT = 0 Hz, BW = 2500 Hz Steady input consisting of white noise plus a CW sign
I've tested 1.373b5, didn't have time to do it with V2. 73, Sinisa YT1NT, VE3EA _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/m