IC-7000_review_AD5X.pdf

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1、ICOM IC-7000 Review By Phil Salas AD5X ICOMs new IC-7000 has more features/cubic inch than any other compact transceiver on the market. Introduction Like many of you, Ive been following the introduction of the ICOM IC-7000 over the past year. Ive owned an IC-706MKIIG since 1999, and it has served me

2、 extremely well over these past seven years both in mobile and portable applications. I have also owned an IC-703 for over a year, and have been well-pleased with this transceiver as well. So when I was asked if Id be interested in reviewing the IC-7000, I jumped at the chance. Not only so I could h

3、ave a chance to evaluate this new transceiver, but also so I could answer two questions: First how does the receiver of the IC-7000 compare to the receivers of the IC-706MKIIG and the IC-703 under the same band conditions? And second is it time for me to upgrade my IC-706MKIIG to an IC-7000? First L

4、ook Right out of the box you can see the more modern, 21st century look of the IC-7000. When compared to the IC-703 and IC-706MKIIG, the IC-7000 has more subtly rounded corners, and flat panel buttons as opposed to the normal looking protruding buttons of the earlier transceivers. Also, the size of

5、the IC-7000 main tuning knob has been increased slightly. Along with the tuning dial diameter increase, ICOM increased the number of buttons on the front panel from 14 to 17 yet the front panel looks less cluttered than the IC-706MKIIG or IC-703. When I began setting-up the three radios so I could b

6、egin my evaluation, I also saw that the IC-7000 is ” shorter than the other radios (9” overall length including knobs and heatsink). The IC-7000 on the left (notice the fan) and the longer IC-703 on the right! But the really attention grabbing physical fea ture of the IC-7000 is that incredible colo

7、r display. And man oh man what a display! While the display is just 2.5-inches diagonally, it provides a HUGE amount of information. It is really something to be able to meter Power output, ALC, Compression, and SWR along with frequency, S-meter and heat-sink temperature all at the same time! ICOMs

8、use of text, figures and colors make the information easy to see. And for mobile operation, select the large text font mode for even easier to read basic frequency information. You can select a black, white, or blue background. My preference is the default black background. Unfortunately, my photos

9、dont give justice to the display. You need to see this in person! Normal Font Expanded Font But to make things even better, the IC-7000 has a composite video output for driving an external video monitor. This is really nice for home station use. Normal text on 13” LCD monitor Expanded text, if desir

10、ed I had heard complaints that the external display output did not look all that good. If that was the case in early IC-7000 transceivers, it is certainly not the case now. I think that the external display quality is excellent. First - A Few Basic Tests While the numbers game has been done in oth e

11、r publications, I did want to make a few measurements prior to actually starting operational and on-the-air evaluations. I focused on 160-6 meters, as I am primarily an HF operator. For details of the IC -7000 operation in the VHF/UHF bands, refer to the excellent review by Steve Hicks N5AC in the W

12、inter 2006 issue of CQ VHF Magazine. My test set-up is shown in Photo G, and a close-up of the three transceivers is shown in Photo H. Authors Test Set-up Close-up of the three transceivers First, I measured the typical current requirements of the IC-7000. The receiver current drain, specd at 1.6 am

13、ps max at normal volume, measured just 1.3-amps at normal volume. The transmitter current measurements at 100-watts output into a MFJ-267 Wattmeter/Dummy Load (160-6 meters) are displayed in Table 1 (spec is 22 amps max): Table 1: Transmitter current requirements at 100 watts output power 160M 80M 4

14、0M 30M 20M 17M 15M 12M 10M 6M 18.4A 16.8A 19.7A 16.2A 19.6A 19.3A 17.0A 20.0A 18.6A 19.5A The transmit power can be varied continuously from 2-100 watts from 160-6 meters. For those of us who may also be interested in using this radio for QRP and/or HF Pack operation, I measured IC-7000 transmit cur

15、rent requirements at 5.3 amps at 2-watts output, and 5.8 amps at 5-watts output. Next, I checked the SWR point where the IC-7000 starts turning down power (SWR protection). I did this by putting an external Diamond SX-1000 SWR meter in series with a MFJ-902 antenna tuner and the dummy load/wattmeter

16、. I tuned the MFJ-902 for a 1:1 match into the dummy load, and then varied the tuners inductor and capacitors as necessary until I could just barely see the output power decrease. Then I measured the SWR into the detuned antenna tuner. I found that the IC-7000 would consistently begin turning down p

17、ower at an SWR between 2:1 and 2.5:1 from 160-6 meters. Finally, I checked the receiver S9 meter sensitivity and S -meter tracking from S-9 to S-1 (dB below S-9). My test equipment consisted of a Tektronix 191 RF generator, a Hitachi V-355 oscilloscope, and a pair of MFJ-762 step attenuators. While

18、there is a certain amount of inaccuracy due to the coarse bar-graph display on the IC-7000, I switched in attenuation just above and below the desired reading to center my measurements. This should make the measurements fairly accurate. The results are shown in Table 2: Table 2: S9 Receiver Sensitiv

19、ity and S-Meter Tracking Band S-9 level _S7_ _S5_ _S3_ _S1_ 160M 70V -10dB -20dB -32dB -44dB 20M 70V -10dB -20dB -32dB -44dB 6M 50V -10dB -20dB -32dB -44dB These results are pretty good! Tracking is about 5-6 dB/S-unit (the “standard” is 6 dB/S- unit). And the S-9 meter reading is at or close to the

20、 “standard” of 50V. Using the IC-7000 Right out of the box, you can just plug in your microphone, dial in your operating frequency, and start operating SSB. Since many functions have their own front panel buttons (such as noise blanker, noise reduction, and manual and automatic notch filtering), you

21、 dont have to go into menus to enable them. But if you want to operate other modes, you need to read the manual. And if you want to get all you can out of this transceiver, you definitely need to read the manual. If you have an IC-706MKIIG or an IC-703, youll find many similarities in the IC-7000 me

22、nu system. However, there are still plenty of differences since so many more features have been added to the IC -7000. First of all, since the IC-7000 is all DSP-based youll find that all the filtering you will ever need is built-in. There are three default filter widths per mode, and two filter sha

23、pe factors for each SSB and CW filter width. And these filter characteristics are easily changed. The IC-7000 also has a 4-bank memory keyer and a voice recorder which can even play back recorded messages on the air. The IC-7000 even has a transmit monitor so you can hear how you sound. And then, of

24、 course, you have speech processing, split operation, band-stacking registers, direct frequency entry with the microphone, etc, etc, etc. So read the manual to at least get a feel for where information is when you need it. In my case, I started out on CW since that is my preferred mode of operation.

25、 Without referring to the manual, I was able to turn-on break-in, set the break-in time delay, and start operating at the default speed of 20 WPM with a paddle. However, I had to refer to the manual to change the keyer speed - which is not quite as convenient as on the IC- 706MKIIG/IC-703. On the ea

26、rlier radios, you push and hold the DISPLAY key for about -second. Assuming that CW speed is selected, you change the speed with the main tuning dial and then tap the DISPLAY button to return you to the previous menu/display setting. With the IC-7000, you first tap the AF SET button to get into “set

27、 mode”. Then punch QS for the Quick-Set menu. Assuming that CW speed is selected, change the CW speed with the main tuning dial, and then push the MENU/GRP key twice to return you to your selected display. So in the earlier radios, changing CW speed required two presses of the same key to get in and

28、 out of the speed setting screen. For the IC-7000, you require four presses of three different keys to get in and out of the speed setting screen. After a little practice though, I was able to do this without giving it much thought. Something ICOM really does well is to base the CW break-in time on

29、a fixed number of dits. This is great, since the break-in time changes proportionately with CW speed. Ive always really liked this feature. I normally operate semi-break-in unless Im trying to nail that DX station in a pile-up. Then I switch to full break-in. The default filters for CW are 1200 Hz,

30、500 Hz, and 250 Hz. I think these are perfect, but they are all changeable if you prefer different filter widths. Just a tap on the FIL soft- key in Menu M3 cycles through the three filters. When I really need to dig out a weak signal, I leave the 250 Hz bandwidth alone, but then turn on the two man

31、ual notch filters and set them just above and below the desired signal - which is extremely easy to do by watching the manual notch screen (just press and hold MN to display) . This really makes the signal seem to pop out of the noise floor! The two notches are easy to set. NF1 is just below, and NF

32、2 is just above center. CW operation was smooth and easy, using either semi- and full-break-in. I normally operate by first turning off break-in to zero-beat a station with a string of dits. As part of this operation, it is easy to determine if my keying speed needs to be changed. Then I turn on bre

33、ak-in, select a filter based on band conditions, and transmit. Next I went to SSB. The first thing youll notice is that the IC-7000 microphone is a little more imposing than the mics of the earlier IC-706MKIIG/703 radios, though the mic is really not that much larger. The more imposing IC-7000 mic i

34、s a result of all the extra things you can do with it - such as direct frequency entry, band stacking registers, filter selection, and many of the things that are normally done through the display menus. IC-706MKIIG mic (left) vs IC-7000 mic (right) I first checked the mic gain by looking at ALC, an

35、d then compression level. Both were perfect for my voice. When transmitting into my MFJ-267 peak reading wattmeter/dummy load, I really couldnt see any difference with the compressor on or off since the peak power stays the same. However, when I set the power meter to read normal power, I could see

36、a difference. With the compressor off, normal talking caused the meter needle to hover around the 10-watt mark. When I turned on the compressor, the needle would hover around the 20-watt mark. I verified this with both the MFJ-267 and a Diamond SX-1000 meter. So it would appear that the compressor d

37、oubles your average power. On the air reports were excellent. I was told that the audio “sounds great”, or “has good fidelity”, or “sounds natural”. When I ran tests with and without the compressor, I was told that my signal level increased by up to an S-unit by some folks. Others told me they didnt

38、 see any S-meter change, but my voice was more “punchy” and easier to understand. On SSB the three default receive filters are 3000 Hz, 2400 Hz, and 1800 Hz. I normally operated with the 2400 Hz filter, but there were several times when the 1800 Hz filter really helped normally on crowded 40-meter b

39、and conditions, and once on 6- meters when there was a great opening and the band was wall-to-wall signals. With the 1800 Hz filter, you do lose some fidelity, but the selectivity improvement often makes a receive signal comfortable to copy under high adjacent channel QRM conditions. In all cases, t

40、he bandwidth and filter shape are extremely easy to change to suit your needs. And at any time, you can just press the DEF key to return to the default filter settings. Hold F-1 and adjust BW with the main tuning knob My last operational testing effort involved using the IC-7000 with my external amp

41、lifier. I have an Ameritron ALS-600 amplifier with an ARB-704 Amplifier Interface unit. I was happy to see that ICOM kept the accessory socket the same as on the IC-706MKIIG. So I just plugged the same ARB-704 ICOM interface cable into the IC-7000. Everything worked fine in SSB. The IC-7000 ALC sett

42、ing on the ALS-600 was the same as on the IC-706MKIIG as well. The only issue was that when using CW, I would normally shorten or lose my first “dit” during break-in. I never really had this problem with the IC-706MKIIG. Since the HSEND output of the IC -7000 enables the amplifi er, I figured that t

43、he HSEND-to-RF Output delay must be shorter on the IC-7000 than on the IC- 706MKIIG. So I connected my oscilloscope to the RF output and triggered it with the HSEND output. I found that on the IC -706MKIIG, RF output starts at 13 milliseconds after HSEND goes low, and full RF output occurs at 15.5ms

44、. On the IC -7000, the RF output begins at 8 ms after HSEND goes low, and full output occurs at 11 ms. I measured the ALS-600 relay enable time at 13 ms. Since typical open -frame amplifier relays take 10-20 ms to engage, you may need to use an external foot switch connected to the IC-7000 HSEND inp

45、ut/output to manually enable the IC-7000 transmitter (leave BRK off) when operating CW with a relay-switched external amplifier. I know that this isnt an issue when using an ICOM PW1 amplifier. But in my opinion, it is easier to justify the purchase of a PW1 if you have an IC-756PRO3 or IC-7800. Rec

46、eiver Comparison Testing This is the part of my testing that I was really looking forward to comparing the receivers of the IC-7000, IC-706MKIIG, and IC-703 under real band conditions. The three transceivers were all connected through RF switches so any receiver could be switched on-line at any time

47、. My IC-706MKIIG is equipped with the standard 2.4 KHz SSB filter, and both 1.9 KHz and 250 Hz optional filters. And my IC-703 is equipped with its standard 2.3 KHz filter, and the optional 250 Hz filter. This gave me the opportunity to compare all three radios with their 250 Hz filters and standard

48、 wide filters (2.3/2.4 KHz), and the IC-7000 and IC-706MKIIG with their narrow 1.8/1.9 KHz SSB filters. My listening tests spanned several weeks, and I tried to concentrate on times when the band was crowded (80 and 40 meters after dark, and 20 meters in the early evening). The first thing I observe

49、d is that under normal un-crowded low noise band conditions, I really couldnt tell any difference between the three receivers. All sounded great. But it was under crowded and noisy conditions where the IC-7000 stood head-and-shoulders above the other transceivers. First, the DSP noise reduction in the IC-7000 is significantly better than in the other two radios. I immediately noted far less of a “hollow-echoey” sound on the IC-7000 for the same apparent amount of noise reduction in the