Ic 756 pro ii pro#
They have helped me out very satisfactory with the few warranty issues I have had.Īs for a rumble on AM - I have examined the transmitted AM signal generated by my Pro II on an HP spectrum analyser, and to me it looks like a mathematically ideal A3E spectral distibution, with sidebands exactly 6 dB below the carrier. In all my years of dealing with them, i have always ound their people quite forthright and easy to work with. I regret that you have encountered difficulties in interfacing with Icom. On my Pro II, I have not heard a rumble under any of the operating conditions I encounter. The decoupling issue was corrected in the Pro II, and the rumble does not appear on that radio. There is a fix for the problem, as described in the QST article. This allows ripple generated by the noise blanker in the presence of strong SSB signals to modulate the receiver audio preamplifier. The rumble is caused by insufficient decoupling of the +8V rail feeding the noise blanker and low-lecvel receiver audio circuits. There is a discussion of the IC-756Pro rumble on my website: This article appears in 'Technical Correspondence', QST, June 2002, page 68. It is fully documented in 'The Icom 756PRO - A Cure for the Rumble', by Tony Brock-Fisher K1KP and Jim Jarvis N2EA. There is a rumble problem in the IC-756Pro. It certainly would affect my decision-making if I were in the market for such a rig. I find the company's attitude about the problem disingenous and probably deceptive. To hear 'The ICOM Rumble' for yourself, go to: I have been told that the older, non-Pro II version does not suffer this problem, but I have not confirmed this through direct monitoring or other means. Technicians with knowledge of DSP have reported the sampling parameters in the Pro II cannot keep up with certain task loading and consequently generate this 'rumble,' which is most often heard among hams who are pursuing enhanced audio techniques. The company even bought advertising space in QST to 'spin' the story in a manner they apparently hoped would allow them to avoid addressing what appears to be a design flaw. Ranking technical people at Icom reached by telephone earlier this year have denied there's a problem. It's a gritty, noisy sound varying in loudness in keeping with the level of voice modulation.
The Pro II suffers from something rapidly becoming known as 'The ICOM Rumble.'With the money saved, I can put up more antennas! As such, when in the market for a 'new' rig, I'll be buying a used FT1000MP, which are currently available in perfect condition for less than the cost of even the 746PRO. The difference is obvious and can be told by just using either rig for about five minutes. Having said all that, I've used the 746PRO and the 756PROII in contest environments, with multiple stations running kilowatts within reach of each other, and neither performs as well under that sort of adversity as the Yaesu FT1000MP. But if the 746PRO lacks this function, that feature alone is worth quite a lot, since the circuitry that makes it happen is quite elaborate.
It also has a really good 'MONItor' function, and I don't recall if the 746PRO even has a MONItor function - don't have one to look at, right now. It also has more front-panel control functions, with less need to resort to menus to make routine changes. It has a nicer display which is more functional, attractive and easier (for me) to read - but of course a nod is as good as a wink to a blind man.
It is larger, and has better spaced panel controls. Peter is at like the IC-756PROII better, from a user perspective and not necessarily any objective analysis. I would like to hear any and all opinions, ideas, criticisms, in comparing the 756 Pro II with the 746 Pro. Is the scope option really worth the extra kilobuck? Are you using it?Īre there clear QC issues that make it worth it?Īre there mechanical differences in the main tuning knob mount and operation that make the 756 Pro II superior here? Is it really worth spending the extra kilobuck to buy the 756 Pro II? These problems were not noted in 756 Pro II reviews, which were almost all highly favorable (Avg = 4.8 out of 5). In eham reviews, fellows found the 746 Pro had knob wobble and binding problems, and in several cases, Xmit failed after two weeks (Avg = 3.8 out of 5). If anything, the 6M receiver in the 746 Pro is hotter. Compared the Rx and Tx numbers in QST reviews, and they are identical considering measurement error and expected variability from rig to rig. Could not hear receiver differences on the air. Went to Denver HRO and tried both 756 PRO II and 746 Pro.
0 kommentar(er)
