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1. #Icom 756 pro ii ci v socket generator
2. #Icom 756 pro ii ci v socket manual
3. #Icom 756 pro ii ci v socket windows

This is an approximate measurement, as the amount of noise reduction is dependent on the original signal-to-noise ratio. This shows an S/N improvement of 8 dB with NR at maximum for an SSB signal roughly 6 dB above noise level. The results obtained are very close to those in Ref.2. In this test, MDS is defined as the RF input power which yields 3 dB unweighted S/N at the output. SSB and CW "Sharp" filter shapes selected.ġ: MDS (Minimum Discernible Signal). Offset tone pitch = 1 kHz (SSB), 600 Hz (CW). HP8640B signal generator, calibrated against R&S URV4-03 RF power meter with 0 dB probe Sinadder 3 configured as true RMS audio voltmeter connected to jack.

To satisfy my own curiosity, though, I ran a few quick receiver tests: MDS, reciprocal mixing noise and filter shape factors.

#Icom 756 pro ii ci v socket generator

A few measurementsĪs the ARRL, RSGB and others have already subjected the Pro3 to exhaustive test suites, I felt that any such effort on my part would be redundant (apart from the fact that my second signal generator is much too "dirty" for meaningful RF 2-tone measurements!) The screen image is brighter and a little sharper, the contrast is much better and the colours are more saturated. I have the impression that the Pro3's TFT display is superior to that of the Pro2.

By being able to leave the bar-graph meter on-screen along with the scope, I learned that compression peaks at 6 to 7 dB when it only shows 2 to 3 dB on the much slower moving-coil meter. There are two clock displays - UTC and local - and a simple screen-saver which displays the owner's callsign moving about on a black background.

#Icom 756 pro ii ci v socket windows

The mini-scope is great - you can now display 3 windows frequency/mode etc., mini-scope and bar-graph meter, filter menu or any other lower window that used to suppress the scope on the Pro2. There have been some improvements in operational convenience. In August 2007, I performed an ALC overshoot test on my Pro3/Quadra station. Positive voltage should never be applied to the ALC jack. 4 bars for the Pro2.Īs is the case for all other Icom HF transceivers, the rear-panel ALC jack is compatible with a negative-going ALC voltage in the range 0 to -4V. The ALC is a little less sensitive I need to set the Quadra ALC menu to 5 bars for 1kW output, vs. The first mixer has lower gain, with the result that the scope module in the Pro3 has its own RF amplifier to bring up the vertical sensitivity of the scope. There has also been a significant gain redistribution. Preamp 1 has negative feedback to improve linearity without compromising NF. In the Pro3, the preamps have been designed for highly linear large-signal handling, consistent with a low noise figure. When switched in, Preamps 1 and 2 do not raise the audible noise level in the receiver as much as they did in the Pro2. S9 + 60 dB signals 1 to 2 kHz above and below our channel edges did not produce any perceptible artefacts in the received audio. In addition, the Pro3's strong-signal behaviour appeared to be excellent.

#Icom 756 pro ii ci v socket manual

I am able (by using a combination of NR, NB, Twin PBT and Manual Notch) to squeeze intelligible copy out of the assorted "garbage" on the band more effectively than on the Pro2. The next day, I was able to sustain the sked with my friend Matt KK5DR somewhat longer, as the Pro3 "hears" signals buried in the noise somewhat better than the Pro2 did. I find myself routinely operating with the preamp off on the Pro2, I invariably had Preamp 1 on. Overall, I would judge that the S/N ratio is better than on the Pro2, even in the presence of power-line noise. The NR and NB appear to have been significantly improved. I was able to work a number of SSB stations on 40m which I would not have heard on the Pro2. Preliminary findings are that it pulls weak, noisy signals out of the noise somewhat better than the Pro2. That evening, I installed the Pro3 in my station. On June 30, I picked up my new IC-756Pro3 (S/N 32025XX) at a local dealer. Adam, VA7OJ/AB4OJ's IC-756Pro III User ReviewĪdam, VA7OJ/AB4OJ's IC-756Pro III User Review Initial observations (July 2005)