I would have bet that I would not have responded to a post on this topic by
Bob, but he did such a nice job on this one, I'll take a chance.
Reef Fish wrote:
> LB> I got my information from ACR over the weekend, including
> LB> information on the Mini B 300. Here are some of the features
> LB> listed:
>
> LB> 1. The first EPIRB designed to operational pressure depths of
> LB> 200 feet.
Bob > It's 300 feet, according to Wayne. Apparently the salesman in ACR
Bob > didn't know as much as he thought he knew? I said immediately to
Bob > Wayne, "Perhaps THAT was why it's called the Mini B 300"! :-)
Glad you did the research. It gives us something meaningful to talk about
on this. I wasn't talking to a salesman at this point, although I did talke
to the sales manager. On this matter, I was talking to the engineer, the
individual who did the tests. As it happens, the tests are specifically
stated in the materials I later received. I'm not at home at the moment,
but I'll supply them when I return. To my recollection, the units were not
tested to 300 feet ever. They were tested (I'll have to confirm to be sure)
to 250 fsw for short and long periods, single instance and repetitive. The
units are rated, by the manufacturer, verbally and in writing, to a lesser
200 fsw to provide a performance margin. In essence, Wayne is mistaken
about the depth rating. Below are the statistics directly from the
company's web site. You'll note in them what looks like the reason for the
300 designation. BTW, I don't think the unit we're talking about is
actually called a Mini B 300. It is based on the Mini B 300. The 200 fsw
unit was, as I recall, was given a different or additional name, but it's
the same unit in a different case. I'll share this too when I get back
home.
----------
User-replaceable battery; unit uses inexpensive, easy-to-obtain common
lithium camera battery, Duracell DL223A (or equivalent)
10-year storage life lithium battery
Frequency stability exceeds ETS 300 152 standard; meets rules for satellite
detection
Output 100 mW nominal (ETS requirement is 75 mW)
Floats if dropped overboard
121.5 MHz (SAR frequency) provides rescue forces with pinpoint homing
9.3 nautical mile satellite location accuracy on first pass
Antenna maximizes peak effective radiating power when fully extended
Compact size with antenna folded; durable double-braided antenna resists
distortion when packed for extended periods
Multiple lanyards allow many secure methods of attachment
LED indicator confirms transmission
Diamond knurling on case improves fit and security of grip
Battery installation instructions included
Operating life: 24 hours @ -20°C (-4°F)
Size: 12.7 x 7.4 x 4.1 cm (5.0 x 2.9 x 1.6 in)
Weight: 215 g (7.6 oz)
Material: Glass reinforced poly carbonate
Color: High-viz optic yellow
Deployment: Manual
Operation: Extend antenna to the full vertical position. Break switch seal,
flip switch forward into "ON" position. A flashing red light indicates
proper operation. To deactivate, flip switch to "OFF" position.
Waterproof: 10.0 m (33.0 ft) Accessories: 9321 - Mounting bracket
Certification: Meets ETS 300 152 requirements; CE Not approved by FCC; Not
for sale in the U.S.
Limited Warranty: 5 years
Carton Dimensions: 12.7 x 24.8 x 19.5 cm (5.0 x 9.75 x 7.5 in)
Units Per Carton: 4
Carton Weight: 1.4 kg (3.0 lbs)
Frequency: 121.5 MHz
Battery Type: DL223A lithium or equivalent
Radiated Power: 100 mW nominal (ETS requirement is 75 mW)
Operational Life: 24 hours @ -20°C (-4°F)
> LB> 3. Long range, boats 5-8 miles, helicopters 15 - 20 miles,
> LB> commercial aircraft, 75 - 100 miles, SARSAT (search and rescue
> LB> satellites), world wide.
> The RECEIVER unit on the boat is capable of all those ranges. But
> the diver units are SHORT RANGE. About 5 miles from the boat and air.
The receiver units are not capable of a specific range. Range is determined
by the transmitter, line of sight and receiver sensitivity. Since Wayne is
a boater and uses the unit on a boat, not a plane, helicopter or satellite,
I think I'll treat the manufacturer's statements are more reliable while
admitting that the manufacturer is likely to be biased. Nevertheless, the
manufacturer's claims are consistent with claims made for other EPIRBS of
similar design and frequency. My research went well beyond ACR.
> LB> 4. Works with the Vectra hand held radio direction finder,
> LB> equipped with a highly directional antenna.
> Wayne said "Vecta" -- he spelled it for me without me asking.
It looks like Wayne is correct and I was wrong on the spelling. Spelling is
obviously not my strong point. Remember, I'm the guy who wrote Rondales for
years.
> He also volunteered that the Mini B 300 has NO GPS interface. In short,
> just as I suspected from the News Release (which made the error of
> the 200 max depth too) that it is merely a SHORT RANGE gadget to be
> worked with a powerful RECEIVER unit on the boat (which cost the
> Fleet about $700). But the Mini B 300 costs the Aggressor Fleet
> only $120 per unit. :-) Now you can infer the profit margin when
> ACR sells it to customers at the $200-$300 range.
He's right about the lack of a GPS interface, but that has nothing to do
with range. There are GPS interfaced units out there, but this has nothing
to do with range. GPS computes present location based on signals from
satellites. I have 2 GPS units of my own, both made by Garmin. One takes
an electronic chart chip and shows my boat's location relative to the
charts. You may assume it was expensive. The other one simply reports
latitude and longitude. It was also expensive when it was new. A better
one is now very reasonably priced. As I recall (I'll have to confirm this
and I don't have time to do it now) EPIRBs with GPS interface compute their
location (for sure) and broadcast it with their signal (this is what I have
to confirm). This improves the ability of search and rescue personnel to
find them, but isn't a range issue. The Mini 300 is no more of a short
range device than any other EPIRB, even if you chose to use capitals, and
the receiver is not powerful. It's still an EPIRB and still designed to
reach search and rescue satellites world wide. That fits my definition of
long range. The receiver is sensitive, not powerful. The receiver is a
passive device to which the attribute "power" doesn't apply. It's ability
to pick up the signal at longer range is determined by line of site, the
power of the transmitter (EPIRB) and by the sensitivity of the unit.
Wayne is using the EPIRB's short range capacity for those who use his boats,
but his use is not the only use for them. This is an important point for
anyone considering the units or using one. Even on the Aggressor, even if
the receiver fails, even if nobody on the Aggressor can get a fix on the
unit, even if you fall overboard at night and are many miles from the boat
when missed, a properly functioning EPIRB will be heard by someone. That's
what they were designed to do. Short range use is an innovative
application, for short range detection, of a long range device.
> The EPIRB units will SOON be in operation in the Palau Aggressor.
> The only OTHER locations in which they will be used by the Fleet
> will be on the TWO Aggressor liveaboards in Galapagos.
> Makes sense. Because those are the only Aggressor dive locations
> that have fierce enough currents to take a diver out of the sighting
> range of even a BIG sausage.
Personally, I think EPIRBs would be a good idea for pretty much any diving
where someone might get separated from their boat. Recent reports of such
separations in Florida, Australia (at least a couple in the last year or
so), and Cozumel all suggest an EPIRB might be a good safety device to
consider, particularly at such a modest price. I'm considering purchasing
one myself, particularly since I dive from a dead (unatended) boat.
> I have NO OTHER INFO to offer, and I have NO desire to follow up
> on this thread because I still have some very bad taste in my mouth.
So rinse your mouth out and stick around. You did well. Imagine me saying
that.
Those that are interested, take a look at ACR's website at
http://acrelectronics.com . They make a lot of very interesting devices you
may like the looks of the Firefly plus with the white strobe (emergency
signal on surface). A backup light and emergency strobe good to 100 meters
sounds interesting to me.
Lee
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