ICOM IC-7700 HF and 6 Meter Transceiver
Reviewed by Rick Lindquist, WW3DE National Contest Journal Managing Editor
The IC-7700's attributes seem shaped more toward the serious contester and DXer, but it's a superior performer with features enough to attract any active HF or 6 meter enthusiast.
Is the ICOM IC-7700 the very competent IC-756PROIII writ large or the top-shelf IC-7800 writ small? That's the nub of the debate raging in Amateur Radio cyberspace. Perhaps it's a bit of both, but the larger question may be: Is this a contester's radio, a DXer's radio or just a big, general-purpose box for someone with a lot of room in the shack and around $7000 of discretionary income?
I've owned a PROIII for about three years and had a PROII before that, so I feel familiar with that segment of ICOM's product line. A collective gasp went up when ICOM came out with the original '7800 back in 2004 and set the retail price above $10,000 — the top of the scale at the time. The advent of the similarly sized but less pricey IC-7700 puts many of the more expensive radio's capabilities within reach of a larger segment of the Amateur Radio population. The overall focus of this review will be to evaluate this radio on its own terms and as a possible next step up the ladder for PROIII owners like me. Let's see how it stacks up. nothing on this baby! The IC-7700 has a slightly different — some say better — look to its case and is a little lighter than the IC-7800. Both units come with rack-mounting hardware, which lends it a professional air but mostly just gets in the way. The handles are handy to lift the radio into place in the shack, though.
This massive transceiver's myriad capabilities and features more than make up for any inconvenience in handling it — or, for that matter, fitting it onto your operating desk. The IC-7700's front panel layout is similar enough to the PROIII's that I got it up and running in no time.
A manifestation of upward mobility for those owning "lesser" radios, the IC-7700 retains many of the niceties ICOM included in the IC-7800, such as a built-in ac power supply, 200 W output on all bands, 6 meter coverage, an attractive and capacious display screen, adjustable DSP filtering, notching, noise blanking, noise reduction, selectable crystal roofing filters and plug-and-play RTTY and PSK31 operation. What it does not offer compared to the IC-7800 may be less obvious.
Inside the IC-7700 are two independent and identical DSP units — one for transmit and receive functions and one for spectrum scope functions. Unlike the IC-7800, the '7700 is a single-receiver design, although it does have two VFOs. It does not have Dual Watch capability, something even the PROIII boasts. More on this topic later.
Similar to the IC-7800 design, the MOSFET power amplifier transistors in the IC-7700 run at 48 V dc, providing 200 W at 100% duty cycle on every mode but full-carrier AM, which provides 200 W PEP, or 50 W carrier. The IC-7700 uses MRF-150s, while the IC-7800 has SD-2931s.
Both radios include the DigiSel automatic tracking preselector, to minimize the effects of strong, out-of-band signals, plus a choice of 15, 6 or 3 kHz roofing filters to pair with each mode's three user-settable bandwidth filter settings. There's a separate front end for 6 meters.
The IC-7700 also includes the handy audio peak filter (APF), which ICOM wisely has resurrected (it was a popular feature on the original-flavor IC-756 but was omitted from the PRO series). Not only is it back, but it's improved, with narrow, mid and wide settings and a number of menu options.
The IC-7700's front end is similar to that of the '7800's, with narrow band-pass filters followed by the DigiSel preselector. The IC-7700 incorporates later-generation DSP chips that boast a slightly higher processing speed than the ICs inside the '7800.
A simulated analog multifunction meter that almost looks like the real thing graces the gorgeous 7 inch TFT LCD display; both radios include provisions for an external VGA video display (the LCD and external displays function simultaneously). I found the '7700's LCD display to be an order of magnitude better than the PROIII's already-terrific display. In fact the difference is so great that the PROIII's display — notwithstanding the praise I heaped upon it when reviewing that radio a few years ago — began looking positively primitive to me. Even so, using an external monitor is the best option if you plan to use the IC-7700 for more than just the occasional RTTY or PSK31 contact. Otherwise, you'll strain your eyes trying to read the text that appears in the tiny decoder window.
One complaint we voiced in the IC-7800 Product Review was that the vertical viewing angle of its display was too narrow. The same appears to be true of the IC-7700's display; it's best with the radio approximately at eye level with respect to the operator. ICOM does provide "lifts" for the front support legs, but these offered insufficient additional elevation with the radio sitting at typical desk height. While the display does fade somewhat when viewed from above or below a line perpendicular to its center, it remains readable at viewing angles of ±45°.
Screen setup offers two display types, A and B, plus a choice of five character fonts. The A screen is a basic black background, while the B screen has a blue background. The screen saver is an eye-catcher. It's a mini-sized floating version of the active display screen as it was wherever you left the radio when you walked away and the display timed out. There are three menu modes for this: BOUND, ROTATION and TWIST.
The IC-7700 offers a choice of three meter styles — standard (analog), edgewise and bar, but you're limited as to which style(s) can appear on either the normal or the wide (expanded) screen at any given time. Using the menu, you can pick any of the three as the default for the normal screen. With the standard meter selected for the normal screen, however, your only wide screen choice is the bar style meter. Otherwise, you're restricted to either a bar meter or an edgewise meter for the normal and wide screens. This means if you go to the wide screen, either two bar meters or a bar and an edgewise meter will appear on the screen for the S meter and power output functions.
The radio includes two USB ports on the front panel for a flash drive and/or keyboard. The IC-7800 has a single USB port on the rear apron and a CF card port on the front panel.
This radio feels really solid, and it definitely will impress visitors to your shack. Everyone who's touched the almost larger-than-life main tuning knob has remarked on its silky-smooth feel. I consider it exceptional; it's a sheer joy to use. I also appreciated that the stem controls along the lower apron of the front panel can hide away when you're done adjusting things. These include settings for DRIVE, COMP, MONI GAIN, VOX GAIN, ANTI VOX, CONTRAST and BRIGHT (for the maximum LCD brightness level).
By and large the whole front panel is user friendly with controls and buttons sensibly grouped, albeit with some exceptions. For example, the SPLIT button on the IC-7700 mysteriously turns up next to the CW PITCH control, not grouped with the other VFO functions as it is on the PRO series transceivers.
I found it was very easy to confuse the vertically aligned and similar-looking MW and MP-W buttons when I wanted to enter a frequency into the "memory pad" (or "scratch pad") memory bank. For that, the MP-W button is the one you want. The IC-756PROIII has a superior implementation. Its memory pad buttons not only are side by side but larger and light gray, which further helps further to distinguish them from the other buttons. The '7700's scratch pad memories will retain a user-selectable 5 or 10 frequencies on a last-in, first-out basis.
A feature I yearned for on the IC-7700 was backlighting for all button and dial labels, particularly those that comprise the keypad. The two-color keypad buttons on the PROIII are smaller, but they're also easier to read than the '7700's when selecting bands or directly entering a frequency. Nonetheless, the front panel controls generally are easy to locate, even if they're not all ideally illuminated or highlighted.
On some concentric controls, I found myself wishing the control I used more often was the inner knob. NOTCH is one of my favorite features for doing a little CW filter shaping, but it's on the ring, making it more difficult to grasp, especially with the rack-mounting hardware in place. Offhand, it strikes me that the NOTCH should switch places with DIGI-SEL, which, quite honestly, I didn't find helpful at all. Unless you are operating in the presence of strong out-of-band signals that might degrade receiver performance, the DigiSel feature is not one that most North American operators will need to take advantage of. It might come in handy in a multi-transmitter environment, however.
The IC-7700 lets you stack three frequency/mode registers in each VFO, A and B, for a total of six on each band. When you "equalize" the VFOs for any reason, you'll overwrite the last-selected settings in the other VFO's register. You can program each band register to recall one of the four antenna port selections.
Using transmit and receive incremental tuning (XIT and RIT), you can shift either or both by up to 9.999 kHz up or down the band. Some operators, me included, occasionally find it more convenient to use the XIT instead of the SPLIT button for split-frequency operation. That way, pressing RIT lets you listen to your transmit frequency and more conveniently tune for a clear spot (it beats holding in the XFC button while trying to tune the main VFO knob, sometimes with the same hand!).
Many IC-7700 users have remarked on how quiet the receiver is. Some also feel the IC-7700 has bragging rights over the IC-7800 when it comes to CW reception. My impression was that the receiver is exceptionally quiet, a real plus in digging out the puny signals prevalent at this point in the sunspot cycle.
The IC-7700's filter menu goes a step beyond what's available on the PROIII. On the '7700 you can set up three discrete filter settings and shape (sharp or soft) as well as one of three preset roofing filter settings, 15 kHz, 6 kHz and 3 kHz. A separate filter shape set mode lets you establish default filter shapes for SSB, SSB data and CW on both HF and 50 MHz. For example, if you set the HF SSB (600 Hz -) filter shape to "sharp," that shape automatically applies when the IF filter is set at 600 Hz or wider. Likewise, if you set the HF CW (- 500 Hz) filter shape for "soft," that shape automatically applies when the IF filter is set at 500 Hz or narrower.
The DSP filters work hand in hand with the passband tuning (PBT) control to permit quickly setting just the right degree of filtering to hear the desired signal. Others who have used the IC-7700 came away with the impression that excellent, flexible selectivity is its strongest suit. The very effective noise reduction system also helps. DSP noise reduction on the '7700 is far superior to the implementation on the PROIII. For starters, there's a lot less high-frequency rolloff and overall distortion with the IC-7700's NR system; the audio remains fairly clean throughout. Advancing the NR control much beyond about 10 o'clock will begin to affect the AF output level, however, but that's probably a trade-off most of us can live with. In any event, I never found it necessary to engage extremely aggressive noise reduction.
By the same token, even while wearing headphones I sometimes felt a little starved for AF gain when using the IC-7700, especially at narrower IF bandwidth settings. As a result, I found myself punching P.AMP 1 to get a little more punch. Even at its highest setting the audio never knocked me out of the chair, although a handy menu feature allows independent adjustment of the headphone level.
Whither Dual Watch?
It actually took me a few hours of using the IC-7700 before it dawned on me that it did not have a sub-receiver or Dual Watch capability. Could this be? My PROIII has Dual Watch; why wouldn't ICOM include it on this much more expensive model?
That seems to be the question of the day on various Internet discussion sites, and for some potential owners, the lack of Dual Watch is a deal breaker. Dual Watch is handy for capturing the "big picture" — by letting the operator listen to the rare DX and the pileup at the same time, for example. The two receivers of the IC-7800 let you listen to one in each ear, a big plus compared to the Dual Watch's single audio channel. Still, many find the Dual Watch helpful. On the other hand, not everyone needs Dual Watch, and most contesters and DXers can work around it by using handy XFC button or by using RIT and XIT.
Related to this discussion is the fact that the display does not show the frequency of the other VFO, unless the transceiver is in split-frequency mode. Otherwise, you can only see the frequency of the selected VFO plus that of a memory channel.
Doing the Numbers Game
We measured the two-tone third-order IMD dynamic range of the PROIII on 14 MHz at 5 kHz spacing, preamp off, at 77 dB. More recent offerings, including the later IC-7800, Elecraft's new K3 and the FLEX-5000A, have raised the bar for this important receiver parameter considerably. Let's look at the hard numbers from the ARRL Lab.
The two-tone third-order IMD dynamic range of the latest IC-7800 model on 14 MHz at 5 kHz spacing, preamp off, came in at 96 dB, noise limited (see "Product Review," Mar 2007 QST). The IC-7700's measurement at the same settings was identical. But wait! There'smore!The IC-7700's two-tone third-order IMD dynamic range measurement of 95 dB on 14 MHz at 2 kHz spacing, preamp off, was 9 dB better than that of the IC-7800 at the same settings. In both cases, the '7700 measurement was not noise limited. Figure 3 shows that the ARRL Lab measured lower levels of close-in composite noise for the IC-7700 compared to the IC-7800. The '7800 does hold a 117 dB to 102 dB advantage in blocking dynamic range on 14 MHz at 2 kHz spacing, preamp off.
On a busy band, it's possible to hear the discrete layers of stations on top of one another. Most times you also can pick out just the signal you want by using the passband tuning and/or APF features. During one operating event, I was able to work two stations of differing signal strength that were almost on the same frequency by using the 200 Hz filter setting coupled with the APF working......
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