Best UHF/VHF HT for emergency transmission?

[Scott Brady]

I am looking at options for an emergency use (back-up) HT that can go in a ditch bag.

For example, middle of Mexico and you need to call out on UHF to hopefully hit a HAM somewhere in the world. What frequency would you use and what unit would you buy to punch out with?



I would prefer maybe a "best of" and "reasonably priced" option.

The Yaesu VX-7R looks very interesting.

I am currently have two Vertex Standard HD HT's (VX-150), but at best I would have a 20 mile range or so.

Thanks

 

[Ursidae69]

For example, middle of Mexico and you need to call out on UHF to hopefully hit a HAM somewhere in the world. What frequency would you use and what unit would you buy to punch out with?

That scenario is pretty much impossible to anyone more than 50 miles or so, less with a HT. On 2M, I'd hail the call channel first. You are thinking HF and most HF rigs are pretty big. There are some HF portable rigs you can get into though, I plan to get one in my truck when I upgrade to the general license.

 

[Scott Brady]

Got it. Thanks Chuck. I thought some UHF would skip off the ionosphere...

So the best chance would be to hit a repeater somewhere nearby, or better yet, to have a Sat. Phone and/or SPoT.

 

[Ursidae69]

Got it. Thanks Chuck. I thought some UHF would skip off the ionosphere...

So the best chance would be to hit a repeater somewhere nearby, or better yet, to have a Sat. Phone and/or SPoT.

There can be some skip, but it depends on weather conditions and the current sun flare cycle. The Yaesu FT-8900R quad band is on my wish list, that means in the next few months.

 

[Azrocks]

I bought the FT8900 for exactly that same reason. You get 6m and 10m capability as well as 2m and 70cm and is in the same form factor as the FT8800. The cross band repeat opens up some interesting options as well using a handheld. Right now I'm set up for dual band configuration only. I plan on getting one of the quad band antennas to get into the HF stuff after I get my license upgraded. It is important to know that you only get the FM stuff though. That is limiting.

I am all about options and this radio offers more even if they are limited somewhat. I need to check to see if you can crossband repeat into 6m and 10m. The price is fairly comperable to the VX-7R. From chatting with the guys who know over the airwaves, any HF in a handheld format is pretty much useless due to power and antenna limitations.

I'm looking more into your question area as well. I'll post if I find anything.

 

[thallca]

My expedition radio kit is built around a mounted Yeasu FT-2800 65-watt 2-meter radio, a yet to be completed portable HF kit with a Yeasu FT-857D and ATAS-120A antenna packed up in a pelican case (I haven't finished the system, still need portable power and antenna mounts) I also use a Kenwood TH-D7A that I have hooked up to a old Garmin GPS II so I can run APRS in my truck. The kenwood and gps are portable so I can take it out of my truck and move it to another vehicle it I have to. I plan on getting a dual-band mobile, don't know which brand yet, so I can use my truck as a cross band repeater if I ever have the need and a mounted radio for APRS. The Kenwood, at 5-watts max output, just doesn't have the power to get to some of the digipeters in my area when I am using APRS. I also picked up two small Yeasu VX-2R dual band handhelds that where on sale at HRO. They are only 1.5 watt on 2-meter and 1 watt on 440. They make really good 'hand-out' radios for those times when you are in a convoy and your buddy's radio craps out while out in the bush.

Tim

 

[Andrew Walcker]

I have the VX-7R paired with a Diamond Antenna and have been extremely happy w/ the transmission and reception. I see that you have a picture of the silver but check out the black finish.

 

[DaveInDenver]

Got it. Thanks Chuck. I thought some UHF would skip off the ionosphere...

So the best chance would be to hit a repeater somewhere nearby

Normally you should only count on VHF and UHF as line of sight. But...

VHF and UHF can experience tropospheric ducting, but it's more by chance of the right atmospheric layers. This usually happens because of a change in atmospheric pressure or because of a storm. It actually happens sporadically here in Colorado where you'll hear a FRS radio down here in Denver from a ski area due to a temperature inversion and I often hear the Breckenridge repeaters in the summer driving home right before or after an evening thunderstorm. What literally is happening is the wave is being bounced back and forth within a thin layer of warm (usually moist) air between layers of cool air on the ground and in the upper atmosphere. If you see lots of smog, typically that can be an indication that you have a temperature inversion and it's possible to get ducting. The signal seems to only travel in the duct, so distance is generally bounded by the edges of a storm or weather features (like a high pressure ridge). If troposphere ducting sets up, it's characteristics are pretty predictable.

Another occurrence is E-layer or F1/F2-layer skip on VHF. I dunno that it would give you a better chance than a troposphere duct, but it can be pretty common. Particularly as you travel further south I understand that E-skip can almost be counted on. This type of skip is dependent on the right ionization bands to form in the upper atmosphere, but when it forms you can skip (HF from 20m and shorter and VHF in particular) for thousands of miles. The problem is that it's hard to predict and not necessarily reliable where or who will be able to hear you on the other end. From Mexico it could be Utah as easily as Denmark or Argentina. It's pretty common for hams to generate sporadic-E maps of what's working and what's not, it's very common on 10 meters (the silly CB DX'ers also try to do it) to take advantage of this. BTW, this actually should work better on VHF than UHF.

In the end, line of sight and elevation are your friends and work all the time with VHF.

 

[Azrocks]

This might be worth checking out.

 

[Azrocks]

I have the VX-7R paired with a Diamond Antenna and have been extremely happy w/ the transmission and reception. I see that you have a picture of the silver but check out the black finish.

Have you had any success on the non 2m and 70cm bands?

 

[DaveInDenver]

Personally I think a VX-7R with antennas to cover 6m and 2m will give you the best chance of DX. That is what I take when I go backpacking or on ski and bike trips, anything away from the truck overnight.

I'm still using the stock rubber duckie, which isn't a terrible one antenna, quad band, solution. Personally I'd like to get a Maldol MH-510 for my VX-7R, 6m/2m/70cm and no worse to carry than the Yaesu one.

For size, weight and performance, hard to beat a roll-up J-pole. I once made one for 6 meters, like here. My workmanship was not great and I didn't have the exact same ribbon, so it didn't last long and I didn't have any luck making a contact on 6m. But based on a 2m one I've used, they are very efficient antennas. Most people build 2m J-poles with 300 ohm flat ribbon cable, but this guy came up with a 6m one using 450 ohm ribbon.

Here's a good example of a typical 2m J-pole. Super portable and it's gonna be hard to come up with a better antenna, performance-wise, than a dipole.

I also sometimes carry a 50' spool of 24AWG wire that on one end I've soldered an alligator clip on. I spin off the little cap on the top of the stock antenna (where you either put the 2m cap or the 6m loading coil) and put the alligator clip on that. I then spool out the wire and throw it over a tree. I can pick up a lot of shortwave with this, it's actually pretty decent. Another reason to like the VX-7R, that SW RX.

 

[Azrocks]

One of the issues I see are that the FT8900 and the VX-7R transmit only in FM in the 6 and 10m bands. Not really used much as far as I can tell. Have you made any contacts at all in the 6m band on your HT?

 

[Ursidae69]

I am looking at options for an emergency use (back-up) HT that can go in a ditch bag.

For example, middle of Mexico and you need to call out on UHF to hopefully hit a HAM somewhere in the world. What frequency would you use and what unit would you buy to punch out with?



I would prefer maybe a "best of" and "reasonably priced" option.

The Yaesu VX-7R looks very interesting.

I am currently have two Vertex Standard HD HT's (VX-150), but at best I would have a 20 mile range or so.

Thanks

Scott, did you end up getting one of these? I just picked up a VX-7R from HRO and I should get it next week. We'll have to do some tests to see how well they work at reaching out.

 

[Cabrito]

I like my VX-7B (B is for black becasue black is cool) - it's sort of hard to program but easy with the software - Waterproof is nice -- The speaker sounds like crap but the HH mic speaker sounds good. I use a comet piano wire antenna - it's nice to fold it over and it looks cool although it's only dual band. I don't ever use anything other than the 2m and 440 bands so the dual band is fine for me.

-Michael

 

[taugust]

I have wanted a mobile HF rig for a long time as a way to get out of the middle of nowhere in an emergency. Baja is a perfect example. The Icom 706MkIIG seems to be well thought of and is fairly compact, with a remote head for vehicle mounting. Yaesu makes a similar rig. Now that I have my general ticket I will probably go that route.

Tim
KG6WFV