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            ICOM IC-7300 Transceiver Overview (Euro/UK version)
         There is plenty of information on the net regarding the great performance of this transceiver so I won't repeat it all here.
This is a truly superb transceiver produced by Icom, there is little wonder that it is proving such a popular rig around the world. The European/UK version of this rig also covers the four metre band with an output of 50 watts and having checked it's output on a spectrum analyser was so pleased to see how clean it's output was. There is plenty of information on the net regarding extending the frequency coverage if you so wish. I have seen a number of comments saying that the fan is too noisy, I agree with these comments and have addressed them here. The main criticism is the fact that it has only one aerial socket which is a very big blunder on the makers part when an additional socket could have been fitted at the manufacturing stage with very little additional expense, it would be rather difficult to retro-fit an additional socket adjacent to the existing one as the central part of the cast chassis would prevent this. It is a real pain having to change over the aerial when moving from the HF bands to Four/Six metres so most people are using an external changeover switch for this purpose. I have made an external aerial changeover relay unit which automatically switches aerials between the HF and VHF bands so that there is no chance of having the wrong aerial selected for the frequency in use. The circuit and info for this and other hopefully useful items are in this section of the site.....................


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As you can see from this picture an additional VHF aerial socket could have been fitted near the existing one at the manufacturing stage but would be a real problem to retro-fit one due to the positioning of the cast chassis.

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​The supplied HM-219 Microphone which provides better quality audio than some of it's predecessors, having said that I use a desk condenser microphone purely for convenience, I use this in conjunction with a foot switch.



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​              "WARNING"
 
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All "In Amateur Band" transmissions between the 160 and 4 metre bands were found to produce a very clean signal, HOWEVER, after doing the usual mod for extending the TX range outside the Amateur Bands a very different story emerged.
A dummy load was fitted to the output of the rig and the power output set to minimum and the signal observed on a spectrum analyser, here are the results...............

Of particular interest is an extremely strong spurious emission which appears in the 54Mc/s region if the transmitter is tuned below 70Mc/s, by strong I mean at the same level as the wanted signal and so although some continental countries are permitted to use the top end of 69Mc/s this is not possible using this rig so BEWARE!      As a matter of interest this problem manifests in the same way on receive resulting in a noticeable increase in receiver noise level out of band because it is also receiving in that 54Mc/s region!
Unacceptably high multiple spurious signals are present between 33 and 74.8Mc/s except of course for the 6 and 4 metre bands 50 to 54 and 70 to 72Mc/s. The whole of the HF range from 1.8 to 33Mc/s was found to be very clean indeed.


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