Any idea how the battery times are calculated on mfgr's websites, i.e. the Uniden MHS450 says 14 hours, the 550 says 10.
Is this basically turning the unit on and letting it sit there not in SCAN mode, just sitting there I presume? Anybody have any real world data of battery times if put into Normal + WX scan? I'm specifically targetting the Unidens but I will absorb data on any of the VHF radios...
Jay
In the Specs usually
The battery life numbers are based on the radio being on, but not receiving anything for a certain percentage of the time, receiving a signal at max volume a certain percentage of the time, and transmitting at the highest power level for a certain percentage of time. I do not recall the actual numbers, but something along the lines of 90% on but no signal, 5% receiving, and 5% transmitting. Somewhere in the specs this info is provided for all the radios I have looked at. You can also get a rough idea by looking at the current draws given in the specs as well.
Your take on 450 v 550, otherwise?
I’m leaning toward the MHS550, unless a Coast Guard acquaintance or local marine store electronics guy strongly steers me toward the supposedly tougher ICOM M88
http://www.boatersland.com/icom88.html
I’d miss the AM/FM/aviation, though.
I need to go find the actual sizes of those two …
45 vrs 550 vrs M88
There are specs on the sizes of the 550/450 on Uniden’s website as you can download the manuals for both. I don’t remember off the top of my head and it hasn’t arrived yet.
The 550/450 and M72 are JIS8/IPX8 whereas the M88 is IPX7.
I think the 450 has a longer rated battery life, 14 hours vrs the 10 on the 550…
I was checking things like sensitivity and selectivity and the M72s are slightly more sensitive but doesn’t look to earthshattering difference in the specs.
Jay
For some actual test
of battery life check this link. They tried to simulate real world conditions.
www.standardhorizon.com/PDF/PowerboatReportsArticle.pdf
ICOM M72 looks much taller/bigger
looks like I’ll be getting the MHS550 
No need to guess…
From ICOM’s website:
Dimensions (W×H×D) (projections not included)
52.5 × 125 × 30 mm
2 1⁄16 × 4 29⁄32 x 13⁄16 in.
Weight (approx.) 280g; 9.9oz (with BP-245)
I know the 550 weighs 8.8oz but I am not sure if that is measured without the battery pack or not. ICOM specifically states that’s with the battery pack whereas Uniden doesn’t say.
550:
Product Dimensions (W x H x D) - 65 x 107 x 35mm
On the above, I assume both do not include the height of the antenna…
So the 550’s base is shorter than the M72’s base but wider and deeper…
Jay
You need to hold them
Unless it is simply not feasible, you really need to hold the radios to get a sense of how well they “fit” in your hand, how easy the control buttons work for you, and how visible the display is for you. do you really need all the “stuff” taking up space in the display at the expense of making important info smaller The size differences are no big deal and they all fit in PFD pockets OK. I would decide on other things, but to each his own. Like how well do the rubber seals actually work covering jacks or are there any jacks to cover. Also, you may find small wobble knobs do not stand up well and may “freeze” if not cleaned/washed regularly. Especially concentric knobs for volume and squelch. Of course you may like the control a squelch ring gives. last, but not least, how easy is it to use/program various features. these things to me are more important than size and “specs” since most of these things have similar RF performance.