COMPLETE IC-7851 TEST REPORT NOW ON-LINE BY ADAM, VA7OJ/AB4OJ

IC-7851

Test Report for IC-7851 July 1 and September 21-22, 2015 by Adam Farson VA7OJ/AB4OJ (Iss. 2)

The following are the results obtained from lab tests which the author conducted on Icom IC-7851 S/N 02001019, kindly loaned by Allan Buckshon VE7SZ. The installed firmware versions were V1.01 for the receiver tests and V1.11 for the transmitter tests. The baseline configuration for all receiver tests was MAIN Receiver, NR/NB/ATT/Notch off, AGC Slow . A. Receiver Tests (July 1, 2015): 1. MDS (Minimum Discernible Signal). Test setup: Marconi 2018A signal generator, 20 dB pad, DUT ANT1 input.

HP 339A distortion meter at EXT SP jack as level meter. 2. NPR (Noise Power Ratio). Test setup: Wandel & Goltermann RS-50 and RS-25 noise generators (fitted with filters per Table 2), MCL 75/50Ω transformer or matching pad for 1940 kHz only), DUT ANT1 input. DUT set to LSB for all test frequencies except 5340 kHz (USB). 2.4 kHz IF filter selected. Noise loading adjusted for 3 dB increase in audio output at EXT SP jack, as read on HP 339A. NPR derived by calculation. 3. RMDR (Reciprocal Mixing Dynamic Range). Test setup: Marconi 2018A signal generator, 3 dB pad, 9830 kHz bandstop filter, 0-110 dB step attenuator, DUT ANT1 port. HP 339A distortion meter at EXT SP jack as level meter. 4. DR3 (2-Tone 3rd -Order IMD Dynamic Range).

Test setup: Marconi 2018A and 2019 signal generators, MCL ZHL-32A buffer amplifiers, MCL low-pass filters appropriate for band tested, 20 dB pads, MCL ZSC-2-1W combiner, 0-110 dB step attenuator, DUT ANT1 input. Test signal level adjusted for 3 dB increase in audio output at EXT SP jack, as read on HP 339A. 5. Roofing-filter bandwidth: As for 1. 6. Spectrum scope RBW: As for 1. 1. MDS (Minimum Discernible Signal) tested on 14.1 MHz in CW mode (500 Hz), Preamp off, 1 and 2 in turn. Roofing filter 15, 6, 3 and 1.2 kHz in turn. The MAIN receiver is tuned to f0 = 14.1 MHz and a test signal applied. For each preamp/roofing filter combination, the input power Pi required to raise audio output noise level by 3 dB is noted. Pi = MDS. NR/NB/ATT/Notch off, AGC Slow for all tests. Refer to Table 1. A variant of MDS is also measured in SSB mode (2.4 kHz) at each of the four NPR test frequencies in turn, for use in calculating NPR. The measured MDS values and roofing-filter correction values are given in Table 2. Table 1: Minimum Discernible Signal (MDS). 14.1 MHz, 500 Hz CW..