Wednesday, June 23, 2010

Yaesu VX-8G

A recent addition to the G4ILO shack is a new Yaesu VX-8G hand held transceiver. In case you are thinking that I need professional help over my addiction to hand held radios you may be right - however a week or so ago I received an email from someone who has a collection of 150!

Long-time followers of my blog may recall that less than a year ago I bought a Yaesu VX-8E APRS transceiver with GPS. However I found that the usefulness of APRS was limited by the lack of digipeaters and internet gateways in this part of the world. I decided to use a smartphone based APRS client, APRSISCE instead and sold the VX-8E shortly afterwards.

Using the cellular network instead of amateur radio has its advantages but it eliminates the interest of seeing how far a little 2m RF can go. Interest in APRS has increased in this area over the last few months so I decided to give RF another go. In the meantime, Yaesu brought out an improved version of the original VX-8R called the VX-8DR and a lower cost version called the VX-8G. So I didn't regret my decision to sell the VX-8R as it allowed me to acquire the updated version.

One of the things I really disliked about the VX-8R was the clunky way the GPS attached externally to the radio (and the absurdly expensive fixing bracket.) The VX-8R (and the updated DR) has a number of other features that I never used and didn't need in an HT: 50MHz coverage (including AM), short wave receive (which was useless anyway without an external wire antenna), a barometer/altimeter and a temperature sensor. Nor did I care that it was submersible. I did lose a brand new HT in the Solway several years ago, but as I didn't immediately notice it had fallen off my belt I never found it again.

The VX-8G lacks these unwanted features and can be set to vibrate when you receive an APRS text message - a new way to get a thrill out of amateur radio! More importantly it has the GPS built into the radio which makes for a much neater package. It costs about the same as a VX-8DR without the GPS option.

The VX-8G is not available yet in the UK so I purchased it from Solid Radio, an eBay trader based in Hong Kong. This was the most expensive thing I have ever bought from a Far Eastern trader and I felt like I was taking a bit of a gamble, but the radio arrived in just over a week and with no unpleasant surprise on delivery.

The VX-8G looks very similar to its older brother but is a little slimmer and lighter. I seem to remember that the body of the VX-8R was metal, or else it had a substantial chassis that added to the weight. With the standard battery installed the VX-8G is noticeably lighter than my Kenwood TH-F7E.

The Yaesu's GPS takes much longer than the one in my hTC smartphone to acquire a signal. In fact after waiting several minutes on first turning on the radio I started to worry that the GPS wasn't working so I stood it out in the garden on a table where it eventually established its position. On subsequent occasions it has still taken a few minutes to fix its position which is a bit annoying.

Operationally the radio appears to be the same as the VX-8R and the menus are very similar. One of the new features is SmartBeaconing which varies the frequency of position reports according to your speed and whether you have changed direction. There are different settings for this depending on whether you are walking, cycling or driving. The original model would only send position reports on a fixed time interval. Once I had enabled SmartBeaconing it sent a very accurate track of my walk.

It is too early to say with any precision what battery life is like but initial impressions are that with the GPS enabled it is pretty poor - a criticism that unfortunately is also true of the smartphone. I used to have a navigational GPS called an iFinder GO2 which ran for about 18 hours on two AA batteries so low current consumption GPS devices do exist - why doesn't Yaesu use them? In the VX-8 radios when you use APRS the problem of short battery life is compounded by the need to disable the power saver (which causes the receiver to listen in short bursts rather than all the time) so you don't miss the start of a beacon or message sent by another station. The VX-8G uses the same batteries as the VX-8R and DR models so a higher capacity pack available, but it is quite expensive.

I am pleased with the VX-8G so far and am looking forward to discovering where I can be tracked from. I think APRS holds some of the same fascination as WSPR on the HF bands in that it is interesting and sometimes surprising to see how far your low powered signals can travel.

I don't know when the VX-8G will be introduced in the UK or what its UK retail price will be but I expect it will still be quite an expensive radio. A pity, as I think the cost puts a lot of people off discovering APRS for themselves.


Lynn (D) said...

The only thing keeping me away from the VX-8x (any of the line) is the fact that Yaesu is keeping the TNC closed. If they would just hook it up to a Bluetooth to serial link or even an external TTL or RS-232 jack, I'd already own one. I'm still looking for a nice, compact, RF APRS solution that can still hook into APRSISCE/32 as well as operate standalone.

Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32

PS. It was pretty cool getting an APRS message from you while waiting in line at the Prado today!

Unknown said...

Hopefully the forthcoming Kenwood TH-D72 will have what you are looking for. I can't rule out getting one if it solves some of the shortcomings of the VX-8G like long GPS lock-up time and poor battery life. I just didn't want to wait, especially since we will be going to Prague soon which appears to have a good APRS RF infrastructure.

It was pretty cool sending a text message to a guy in Spain using a ham radio handheld!

Anonymous said...

It takes longer to acquire the first GPS coordinate using pure radio which uses signals from several sattelites.The cell phones use what is called assisted GPS which basically primes the process of getting a fix via cellular triangulation using cell towers. The cell towers operate as ground based psuedolites. The pure radio method is much more accurate and reliable when you find yourself out of range of cell towers. It's just a bit slow getting started.

Unknown said...

True, Sean, but the Kenwood TH-D72 manages it much faster, also using pure radio. Despite that I still prefer the VX-8G.