Sunday, November 13, 2022

Looking ahead to the ICOM IC-905 VHF, UHF & Microwave Transceiver

Back in the first half of 2022, I was following the progress of what was termed the 'ICOM SHF Project'. ICOM first announced this in December of 2021 and it suggested that they were developing a transceiver for the 2.4 GHz and 5.6 GHz microwave bands. See my earlier post HERE.

The blog post got a good deal of traffic and it was obvious that a lot of people were interested in this product even if was supposed to be for only two microwave bands.

I don't think many people had an idea earlier in the year just what ICOM had in the pipeline and it turned out to be pretty amazing.

In this post, I'll look at the new IC-905 in two parts. The first part is a summary and if anyone wants to look at the finer detail, that will be in the second half of this post further down.

In a future post, I'll look at the 10 GHz system.

Part 1 - The ICOM IC-905 in summary

The ICOM IC-905

At the Tokyo Hamfair in August of 2022, ICOM announced their new IC-905 radio which covers the following bands...
144 MHz (2m)
432 MHz (70cms)
1296 MHz (23cms)
2.4 GHz (13cms)
5.6 GHz (6cms)

They also have an optional transverter for 10 GHz (3cms).

As you can see from the photo above, it does have a similar appearance to the current IC-705 model which covers all of the HF, 6m, 2m & 70cms bands.

Note however that there is no RF in this part of the IC-905, it's just the control unit. The radio itself or at least the RF part of it is in the head unit which goes up next to the antenna.

This is part of the concept of putting the control unit indoors where the user is and putting the radio (RF) section up at the antenna. The 'LAN Cable' connecting the two will use PoE (Power over Ethernet) which will carry power and control signals up to the RF module as well as transferring the signals from the radio back down to the controller.

The main point here is to eliminate losses from coaxial cables running from the radio shack to the antenna. These can be really high at UHF and Microwave frequencies.

Some features of the IC-905 system...

1) The power output is 10-watts on 144 MHz, 432 MHz and 1296 MHz from a single N-Type connector. There is a separate SMA type connector for 2.4 GHz and 5.6 GHz and the power on those bands is 2-watts.

2) The controller has a 4.3 inch (11cm) colour display and as you might expect, a real time spectrum scope and waterfall display.

3) All the usual analogue modes like FM, SSB & CW as well as the D-Star digital mode which is standard for an ICOM radio.

4) One nice feature is ATV (Amateur TV) in FM mode.

5) One feature of huge importance is that the RF module will be frequency locked by GPS. This is a major shortcoming in several of the existing ICOM rigs on the market in that frequency drift on some digital modes on the UHF bands is a major problem. The GPS locking should help resolve this.

Price & Availability...

As of November 2022, ICOM have not announced a price for the IC-905. I suspect it will be in the $2000-$2800 price range but we'll have to wait and see.

As for availability, they haven't announced it. I suspect it will be the second half of 2023 before we see any units for sale.

Game Changer...

When ICOM released their IC-705 radio, there was huge interest in it despite it being a low power 10-watt radio. One of the key selling points is that it was a 'shack in a box' with all of the bands from 1.8 MHz to 432 MHz in one unit.

In a similar vein, the new IC-905 is very much a 'shack in a box' for the VHF bands and above. If ICOM had announced a new VHF/UHF radio with just 144 MHz, 432 MHz & 1296 MHz, there would be a lot of interest in it. The fact the IC-905 has 2.4 GHz and 5.6 GHz as well is pretty amazing.

I suspect the biggest change will be to the 1296 MHz or 23cms band. There is a serious lack of radios available for this microwave band and getting a separate radio for just one band is prohibitive.

Close up of the base of the Diamond X6000A

I can see a LOT of people buying Tri-Band type verticals made by the like of Diamond and Comet and using them with the new IC-905. I think it's going to generate a lot of activity on the 23cms band in urban areas in many parts of the world.

The thing about a radio like this is that it is really versatile. People may come up with new ways of using it that we haven't considered at the moment.

I can really see this radio being a game changer for the UHF and low microwave bands IF the price isn't too high.


Part 2 - The ICOM IC-905 in more detail

IC-905 Controller... Let's have a look at this is a bit more detail.

The image above shows the front of the IC-905 and you get some idea of the depth as well.

The photo above is of the front of the controller from the Toyko Hamfair last August.

The photo above shows the rear of the controller and again, you get some idea of the depth.

As you can see from the photo above, there is very little on the rear of the controller other than two heatsinks.

While the IC-905 uses a 12-volt supply, it seems likely that there is a much higher voltage going up the Power over Ethernet cable to the RF unit. It's likely that there is some type of switch mode power supply in the controller to generate this higher voltage and a reasonable heatsink is required for that. There are of course all of the low voltage supplies to all of the electronics in the controller as well and again, a heat sink aids in keeping things cool.

The image above shows the right hand side of the controller. 

The image above shows the right hand side in more detail. The port with the Green LED and the cable in it is the Power over Ethernet cable that goes to the RF module.

The image above shows the left side of the controller with the various ports.

The photo above is an actual photo of the left side of the controller.

And now onto the RF module. This image above gives an overview of the underside of the RF module. From left to right...

a) The cable on the left is Power over Ethernet LAN cable from the controller unit. 

b) The BNC socket has an RF output at 10 MHz which is controlled by a GPS unit inside the RF module. The 10 MHz signal reference from here is fed to the optional 10-GHz transverter and provides that unit with a stable frequency reference.

c) The connector on the right is for the CX-10G which is the optional 10 GHz transverter.

This image above is another view of the underside of the RF module. 

The image above is the top side of the RF module. All 2m, 70cms & 23cms signals are fed out via one N-type socket. Both the 2.4 GHz and 5.6 GHz bands have their own individual SMA socket. There is also a SMA socket for a small whip antenna for to receive GPS signals.

The image above gives another view of the top side of the RF module.

The image above shows the top side with the GPS antenna connected.

The image above is an actual photo of the RF module on display at the Tokyo Hamfair.

If we consider that a N-type connector is about 2cms in diameter then the dimensions of the RF module above is about 18cms across and 26cms in height. The depth is perhaps in the region of 8cms.

In terms of operation, the new IC-905 is basically the same as the popular IC-705.

This image above is a screenshot from the controller showing it operating on the 5.6 GHz band with a selection of modes.

The image above is a screenshot of the 11cm display showing a selection of menu items.

One amazing feature of this radio is it's ability to use ATV (Amateur TeleVision). In the above image, you can see a received ATV signal inset in the screen.

And this is the received signal on full screen.

ICOM also intend to sell omni-directional antennas for both the 2.4 GHz and 5.6 GHz bands.

I suspect third party antennas for these bands will be a lot cheaper.

Video... and finally, this is the promotional video from ICOM for the IC-905

That's it. I've done my best to collate all of the information available and put it in one spot. We'll just have to wait now until ICOM announce a release date and price.

Addendum 25th Dec 2022... At a recent presentation, ICOM had this slide which showed the frequency stability of the new IC-905 versus the old IC-9700.

The IC-9700 which was released in 2019 and is a VHF/UHF transceiver covering 2m, 70cms and 23cms. It is not frequency disciplined by an external source and as can be seen from the chart on the left, it can drift hundreds of Hz with a change in temperature on the 23cms band.

This isn't an issue on say FM, D-Star, SSB or CW but it is on the very weak signal modes like FT8 or WSPR where a high level of frequency stability is required. This has led to some third party providers providing frequency stability solutions.

The chart on the right by contrast is that of the IC-905 at roughly four times the RF frequency. The IC-905 which is frequency stabilised by GPS only drifts a few Hz with changes in temperature.

This really is a game changer for all the VHF, UHF and SHF bands as frequency stability is now essential for very weal signal modes.


1) More info about the IC-905 on my Microwave page


Anonymous said...

Currently using an IC 9700 for satellites and EME. I’m also looking forward to the 905 and EME on 13cm. Concerned we may eventually lose the 23cm band or be limited in ERP due to RNSS. I took a page from ICOM’s design of the 905. I have been putting the 9700 out at the antenna with the SSPA and running it on WSJT-x from a laptop over an 8m USB cable. That has reduced feedline losses on 23cm considerably! (I use a folding 1.8m dish that’s portable due to housing restrictions.) 73!

Ray KN2K

Anonymous said...

Thank you very much for this analysis which is always good to read again. I hope it arrives soon, it's really a game-changing position with other manufacturers. Christophe, F4JMQ.

EI8DJ said...

Great post John, nice rig for all modes, but for ATV, one would like to see a modern DATV mode like DVB-T or DVB-S included.

Robbie Ei2iP said...

Pre-Ordered the ICOM IC-905, I have the ICOM IC-9700 which is a super rig for VHF/UHF especially for the Satellites.

Pity the Diamond X-7000, 2m/70/23cm is not available for the moment, but I plan to use directional antennas.

De Ei2iP/KD2ZZJ, Robbie

Roger G3XBM said...

It looks an interesting radio, although I fail to see ICOM making any money from it. The whole thing looks expensive. I cannot see them selling more than a few thousand, which might just recover their development costs. Time will tell.