In 2020, ICOM introduced the IC-705 radio, a 10-watt QRP multiband multimode portable capable of operating from all bands from 160m (1.8 MHz) to 70cms (432 MHz) with the exception of the 4m (70 MHz) band.
For a low power radio, the amount of hype and buzz surrounding it has been amazing. There has been a host of online reviews, blog posts and videos about it but they tended really only to concentrate on the radios features rather than its performance.
In addition, I think it's fair to say that a lot of the reviews were done by HF operators. I saw one person doing a frequency stability test on WSPR on 20m (14 MHz) which was frankly useless as it meant nothing. Frequency tests need to be done at the highest operating frequency on the radio i.e. 432 MHz where the changes would be the biggest.
RadCom Review... In the April edition of RadCom magazine, a full review was carried out by Peter Hart, G3SJX. Peter carries out extensive performance tests of radios on his bench on a regular basis and his reviews are highly regarded as they're seen to be truthful and honest. If there is a problem or issue with a radio then he calls it out for people to see.
The review is quite extensive running to five pages but I noted that he mentioned some 'low level intermodulation products' appearing with some 'quite small input signals' on the VHF bands. Whether you'd notice these or not I guess might depend on how RF quiet your location is.
One of the big questions that VHF operators had about this radio was about its frequency stability. The previous IC-9700 was known to drift and many VHF guys had to add third-party GPS locked frequency standards to overcome this. Would the IC-705 have the same issue?
When the IC-705 was introduced, it was mentioned that it had a built in antenna for GPS and some people speculated that the frequency stability might be GPS locked as a result.
Peter confirms in his review that the IC-705 uses a high stability temperature controlled crystal oscillator to achieve a performance of 0.5 parts per million (PPM). The built in GPS is as far as I know just there primarily for D-Star operation in terms of timing and location.
I did however come across a YouTube video today from Hayden, VK7HH who did a frequency test on 432 MHz with WSPR.
While the IC-705 did drift 2Hz over the two minute transmission, it did stay within the required 4Hz window for the mode.
In Conclusion... In his final summary, Peter G3SJX concludes..."The IC-705 is a great take-anywhere QRP radio, ideal for all outdoor activities and SOTA expeditions. Covering HF through to the UHF bands with all-mode operation, a top-level performance and extensive remote connection capabilities, it is quite a remarkable piece of kit. Currently priced at £1300, it is excellent value for money."
It might be outside the price range for some but it looks that it's a great radio for those who can afford it.
RadCom... RadCom is the journal of the Radio Society of Great Britain and is posted out on a monthly basis to all members. A digital version is also available on their website for members to view and each issue stays there for 12-months.
The RSGB website can be found at https://rsgb.org/main/
Addendum: Snippet from the review done in QST magazine...
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