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P O L Y T E C H . N U
Nederlands

Icom IC-7300 HF+6+4 base transceiver

introduction
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"The radio that changed the world!" Well, this sounds exagurated, but the introduction of the Icom IC-7300 did change the world. Untill the introduction of the IC-7300 most if the radio's were designed the traditional way using a mainly analog signal path. "Modern" radio's are/were digitally controlled using rotary knob encoders, digital buttons, digitally controlled signal path switches and so on. Also audio filtering using chips is nowadays (2016) quite common. But mixing and filtering is (untill now) mainly done by alalog circuitry. Okay, there are fully software defined radio's on the market, but it's a "box with an antenna, USB and power connector". This "box" is controlled by a personal computer. The performance of this type of radio seems good (I haven't got personal experience wit this). But for most of the hamradio operators (like me) this type of radio is a bridge too far. Personally I like a "radio with knobs". Controlling a radio using dedicated knobs is much more intuitive for me than controlling a radio using a keyboard and computer mouse. Icom took the best of both worlds and created the IC-7300. The "heart" of the radio is a FPGA chip that handles almost all the signal processing. There is an analog receiver circuit and transmitter circuit only the parts that cannot be replaced by digital signal processing. Traditional signal mixing and filtering is replaced by software. This improves the performance a lot compared to traditional signal handling. The other good thing is that the frontpanel does have buttons, knobs and a very nice touchscreen. Controlling the radio is great. 90% of the functionallity can be found out by doing instead of reading the manual. Yes, I first plugged in the radio and after two days I started reading the manual for specific functions like how to save a screen capture. (Short press of the power button after turning this option on via thet menu: Set > Function > Screen Capture [POWER] SW.)

+ Very nice performance due to signal processing
+ Low priced! Yes, it's a lot of money, but compared to performance it well worth it
+ Schematics supplied! (On cd-rom)
+ Three connector supplied for acc, apeaker and key
+ Relative small and lightweight
+ Very nice band scope with a lot of setting options like speed, bandwidth and sensitivity adjustment

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Icom vs Yaesu
Untill now I was a "Yaesu man". I owned some (older non HF) Icom radio's but I preferred Yaesu. I owned the FT-817, FT-857, FT-897, FT-450, FT-991 and FT-2000 HF radio's of Yaesu. There all great in it's own way. Most of the connections were made using the FT-897 "shack in a box". It's small, has also VHF and UHF in it and operates quite nice. Altough the pre driver faild some day and menu controlled switching of the RF gain/SQL knob wasn't great, I still like this radio. The FT-2000 is a great radio! The handling of the controlls is great. But it's clear the design of radio's is evolved. Due to the fundamental design of intermediate frequencies (IF), the FT-2000 cannot handle 70 MHz.

Intermediate Frequency
The intermedia frequency of the Icom IC-7300 is 36 kHz. Yes, that's correct, 36 kHz. There's only one IF stage. The mixed signal is processed further in the chips. Therefore it's possible to use the 70 Mhz band. In comparison, this isn't possible with Yaesu radio's. The intermediate frequencies of VFO A of the Yaesu FT-2000 (2009) are 69,450 MHz, 450 kHz and 30/24 kHz (depending on the mode). Therefore it's not possible to use the 70 Mhz band since 69,450 MHz is the first IF. For the FT-897 are the frequencies 68,33 MHz, 10,7 MHz and 455 kHz. Since both radio designs are rather "old", this is no big surprise. But the FT-991 radio has 69,450 MHz, 9 MHz and 24 kHz as intermediate frequencies. This rather new radio has also 69,450 MHz as the first IF. Therefore the FT-991 is not suitable for the 70 MHz band, but luckily the FT-991 toes have the 2 m and 70 cm band.

band scope
The Icom IC-7300 band scope is great! The waterfall speed can be set. The sensitivity can be set easily to optimize view. The bandwidth can also be set. When the screen is pressed, the selected part is magnified for detailed view. And last but not least, the band scope and waterfall are working during reception. I currently own a FT-991 and this radio is incapable of showing the band scope during reception. I like Yaesu equipment, but this is definately a design flaw. Icom did a better job here. There's a "replacement" radio, the FT-991A with a new control board making the band scope available during reception. The FT-991 can be upgraded to a FT-991A by replacing the control board. Since this probably a FPGA software update, I'm surprised that the updat cannot be done by reprogramming the chip(s).

Here's a animation of the waterfall spectrum if the IC-7300. Since this are loose screen captures added together, this isn't a real world video, but you get probably the idea. In real life the waterfall is slower and therefore smoother. Just take a note of that...
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Sherwood list rating
The Sherwood Engineering list is well known for rating receiver performance. The Icom IC-7300 is now (20161111) at ranking 13! The (very) short version of the list is shown below. For comparison I wrote down the prices of the specific device. Note: These are roughly rounded numbers, just to show the relation between ranking and price. It's suprisingly that the IC-7300 is rather low priced compared to the position on the list. Some radio's are ten times more expensive and perform similair. Beware that the list is primerely based on the receiver quality and not built quality for example. Do check http://www.sherweng.com/table.html for the complete list and details. Thumbs up for Sherwood Engineering!

1 = Flexradio Systems 6700 = $7.500
2 = Elektraft K3S = $2.900,00
3 = Elektraft K3 = ?
4 = Icom IC-7851 = €12.000
5 = Hilberling PT-8000A = €13.290
6 = Elekraft KX3 = $1.050
7 = Yaesu FTdx-5000D = €7.350
8 = Elektraft K3 = ?
9 = Apache ANAN-200D = $3.000
10 = Microtelecom Perseus (receiver) = €850
11 = Flexradio FLEX-5000A = $2.800
12 = Ten-Tex Orion II = $4.300
13 = Icom IC-7300 = €1.300

preamp/attenuator
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more info will follow
There's a lot to tell about this radio and I will tell a lot about this radio. ;-) But since the lack of time, the rest of the information will follow one in a while by small pieces of information. Hi-res inside images for example will follow... Please check the page one in a while for udates.