Low phase noise (low noise on the Local Oscillator).
Low noise floor (copy very weak signals). Ģ Considerations in Choosing a Transceiver High close-in dynamic range (copy S1 in crowded band). 20 kHz dynamic range test showed no hint of the problem Solution: Solution Place test signals close together so they pass through 1st IF filter the Next Amplifier Mixer Close-in dynamic range numbers are ALWAYS worse than the wide-spaced numbers, for a radio with a single wide Roofing filter. If the first IF was 6 - 20 kHz wide, be it at 5 MHz, 9 MHz or 45 - 70 MHz, the radio could overload in a CW pile up. A 20 kHz Dynamic Range measurement in a multi- conversion radio only tests the radio's front end. Dynamic Range - measures the ability to hear weak signals in the present of near-by strong signals. The ARRL dynamic range test did not approximate a real- world environment, especially in a CW contest. R-4C tested well for Dynamic Range, but flunked CW. Dynamic Range, new concepts for the amateur. Used it during the ARRL 160m CW contest Radio performed miserably, yet Specs Were Good 1970s: League expanded testing to include Noise Floor &. What's important when it comes to choosing a radio? Sherwood Engineering Why Did I Start Testing Radios ? Purchased a new Drake R-4C in 1972. Roofing Filters, Transmitted BW and Receiver Performance Rob Sherwood NC ØØØØB What’s important when it comes to choosing a radio? Sherwood Engineeringġ Roofing Filters, Transmitted BW and Receiver Performance Rob Sherwood NC B.
Roofing Filters, Transmitted BW and Receiver Performance Rob Sherwood NC B.
In the IC-756Pro III, it is possible to program each of the three settings individually with the following preset cutoff frequencies: Lower -6dB point: 100, 300 and 500 Hz., Upper -6dB point: 2.5, 2.7 and 2.9 kHz.Example: marketing Search Roofing Filters, Transmitted BW and Receiver Performance The lower and upper -6dB points of the transmitted audio-frequency response are fixed for each setting. The IC-756 Pro II provided three selectable TOBW settings: WIDE/MID/NAR.
Soft and sharp filter shapes can be selected in both SSB and CW modes independently, Programmable SSB transmit bandwidth, microphone equalizer, manual notch function, digital twin pass band tuning (PBT), all mode, including PSK31. 32-bit floating point DSP Digital IF filter with 51 selectable bandwidths. Real-time spectrum scope with mini-scope.
121 position microphone equalizer.Ĭovers the nine HF bands and 60-meter plus 6 meters. Soft and sharp filter shapes can be selected in both SSB and CW modes independently, microphone equalizer, manual notch function, digital twin pass band tuning (PBT), all mode, including PSK31. 32-bit floating point DSP Digital IF filter with 41 selectable bandwidths, microphone equalizer, manual notch function, digital twin pass band tuning (PBT), all mode, including PSK31.Ĭovers the nine HF bands plus 6 meters. All successors required no additional filters.Ĭovers the nine HF bands plus 6 meters. 4.9 inch monochromatic TFT dot matrix LCD display.