McMurdo or Acer EPIRB ?

[fins2yaa]

Went to the Ft. Lauderdale show and stuck between the McMurdo and ACR Epirb with the built in GPS. McMurdo will provide free batteries every 5 years. Does anyone have any of these and what you do recommed?

If you are chartering an uninspected vessell, do have to have one on board?

Thanks,
Fins

[Glen E]

ACR 406 globalfix for me....

[First Light]

McMurdo needs to do something like providing free batteries in order to gain public acceptance because their EPIRBs have been problematic. In the rare instance when you might need an EPIRB to save your life, do you really want to rely on an EPIRB that has failed the CG and NOAA's tests, and then when the problem was supposesdly corrected, McMurdo would not allow their EPIRBs to be recertified by an independent testing facility.

Personally, it's ACR for me.

ACR GlobalFix 406. McMurdo has had issues in the past...

[Texel Tom]

I think I am correct in saying that the ACR GlobalFix is the only one which allows you to do a one off initialisation of the GPS so that in an emergency the response time is much quicker.

TT.

[fins2yaa]

Thanks for all the info, I will go with the ACR.

Thanks,

[parnine]

fins2yaa,

If the above posts are enough basis for your decision, I offer that you've not done enough research. For one thing you should remember the rather 'extreme bias' that occurs on the THT with regards to certain products.

Google 'mcmurdo+gps' or 'mcmurdo+acr+gps+review', etc. and do some more research. I remember I found lots of info a few month back when I was trying to decide and did have

http://www.equipped.org/406_beacon_test_toc.htm

as a saved bookmark, but I think I got this link from another review, possibly on "pano's" (sp? - also google 'pano') site (an excellent side for objective and 'test based' analysis/reviews of products.

Ultimately I decided that there were pros and cons to both, but leaning toward the McMurdo.

Good luck

[First Light]

parnine - 11/1/2006 Ultimately I decided that there were pros and cons to both, but leaning toward the McMurdo.

The cons from the independent tests were that some of the McMurdo EPIRBS would not transmit when they were wet.

What are the cons of the ACR EPIRBS?

[Texel Tom]

Not sure if this is relevent but McMurdo is currently up for sale having already sold off the light division. They lost a lot of cash re-calling all the EPIRBs to fit additional bouyancy. To be fair the new generation ones are out now with these issues apparently resolved.

Don't forget with both brands the GPS function offers faster response not necessarily increased positioning.

TT.

[ACRguy]

Texel Tom - 10/31/2006 3:37 AM

I think I am correct in saying that the ACR GlobalFix is the only one which allows you to do a one off initialisation of the GPS so that in an emergency the response time is much quicker.

TT.

I work at ACR and want to clarify your understanding of our GPS Test in our GlobalFix 406 EPIRB.

We purchase GPS engines with software specifically designed for "cold start applications". This allows our GPS to acquirer data faster then the typical marine GPS. Out of the box, typical GPS engines will download an almanac of data which can take several minutes. The next time they are activated they acquirer position data much quicker because of that stored data.

Our GPS engines are tested when we receive them, again after they are mounted to the circuit board, then again after they are installed inside the beacon housing. The completed beacon is then packed up and shipped through distribution to you. Our beacon features a self test procedure that allows you the owner to test the GPS one more time to insure it is able to acquire position data before being placed into service.

The battery power in any beacon is at a premium and it is reserved for transmission of the distress message. Any data downloaded during that GPS acquisition test is not saved. The benefit of this test is for you the owner to know that your beacon operates correctly and can be relied upon. There is enough power in our battery packs to allow for monthly self testing of the beacon but not to fire up the GPS each month. We need to make sure that after five years of storage and self test our beacons have enough battery power to transmit for 48 hours at temperatures down to -40F. (To cold for me!)

All of my post so far has to do with acquiring GPS position data and adding it to the distress message. When you mentioned response time in your post there are a few points I want to mention.

GPS is an enhancement to the COSPAS-SARSAT satellite system. Without GPS data in a 406 message on average world wide it takes 1 hour to hear the distress message, determine a position, phone your contacts in the registration data base, and marshal the closest rescue asset to launch a mission. When GPS position data is added to the distress message, this notification time is reduced by 45 minutes. The initial search radius is reduced from 2nm to 110 yds.

Getting GPS data into the distress message early when a beacon is activated provides the greatest advantage of time and accuracy. This is why acquisition time is so important.

I hope my comment have been helpful.

Stay Safe

Chris

PSA. Register your beacon on line at www.beaconregistration.noaa.gov
Registration is free, easy and it is the law.

[Glen E]

class post from Chris - rebuttal from McMurdo?

Buheller?

Anyone?

Glen E - 11/1/2006 12:43 PM

class post from Chris - rebuttal from McMurdo?

Buheller?

Anyone?

The fact that McMurdo had transmission issues is enough for me. Ive seen 2 ACR GlobalFix's activate and let me tell you- the Coast Guard and police showed up to each quickly (The National Guard actually showed up to one). Ill put my life in the hands of ACR before McMurdo ANYDAY

[Ewpl]

ACRGuy

How can I test my ACR EPIRB to see if it's really sending out a signal?

[Texel Tom]

Chris

Thanks for the info.

What can you tell us about the partial co-ordinates (short protocol) which are transmitted? Does this really still give you a position down to 110yds?

And is the response time quicker by using geo-stationary satellites rather than orbitting satellites?

TT

[DriftR]

I went with ACR and bought mine through BOE on this Board. Great place to do business with. I would not hesitate to recommend BOE and ACR together in the same sentence.

[parnine]

Glen E - Have you even read any other information regarding this subject in an effor to actually help fins2ya? What was your ACR buying decision based on?

ACRGuy - thanks for the information. Have you seen the report and work of the 'equipped to survive foundation'? If so, thoughts? If not be interested in your opionion/analysis/response after you've read it.

Also curious about any studies ACR has done regarding antenna design and the impacts of a device that does not sit upright in the water and if you could elaborate on Paul Hardin's (with ACR) comments ".....Having discovered this issue, we have addressed it by buying a GPS simulator in April 2005 in order to have the ability to measure GPS receiver performance. We require that our GPS receiver suppliers provide us with units that meet our performance specification. With our GPS simulator we can test/measure/screen units to insure that they meet our performance specs..." with regards to how many units you find 'out of spec' and other findings you've had since incorporating the simulator into you production verification process?

Also, given that the ACR device which failed the test was found to have a GPS receiver with sensitivity measured at 4dB worse than normal, and ACR now has "much tighter performance specifications", can you elaborate on what "much tighter is"? How would a customer of ACR ensure he/she did not purchase a device that would not have the sensitivity to acquire a signal in 'storm conditions'?

Could you also tell us the current ACR hardware and software versions for ACR's AquaFix 406 GPS I/O Personal EPIRB?

Thanks

[1Bigtrouble]

Just got one ACR 406 Global fix $ 677.

[Glen E]

parnine - 11/1/2006 5:26 PM

Glen E - Have you even read any other information regarding this subject in an effor to actually help fins2ya? What was your ACR buying decision based on?

my buying decision was based on many things, the PBR reports and getting on every boat amoung my friends that had an epirb and it was an ACR. ACR is also located about 5 miles from my house and had great reports about their customer service.

I have nothing against the mcMurdo, just would like to see someone from them post as well as Chris did, the more Mfrs that post here with tech info, the more valuable the content of THT....

[First Light]

ACRguy - 11/1/2006 I work at ACR and want to clarify your understanding of our GPS Test in our GlobalFix 406 EPIRB.

Thanks for taking the time to do that, as well as the other information you shared.

[Wahoo U]

ACRguy and I work together at ACR. Chris called me a bit ago and said I was being quoted on THT...

Texel Tom; Yes, you can expect position accuracy of 120 meters or better. The protocol restricts the amount of accuracy that we can transmit, but it should never be worse than about 120 meters from the actual location. HOWEVER, they use the strobe light and the 121.5 homing transmitter to locate you in the final stages of a search. The greatest value of having GPS is that it increases the chance of the USCG knowing where you are and that you are in trouble in the least amount of time. The Geostationary Earth Orbit (GEO) satellite that monitors the Atlantic "hears" the signal real time, but doesn't know whether you are off the coast of Greenland or Terra del Fuego. The imbedded GPS data lets the USCG know you are off the coast of FL and that your alert message should be routed at once to District 7 Miami...for example. The Low Earth Orbit (LEO) satellites will "hear" you also. If one just happens to be overhead when you activate your beacon, then the LEO will "hear" you at the same time the GEO does. On average, world wide, the GEO will “hear” you 46 minutes faster than the LEO.

Parnine; ACR is the only beacon manufacturer that I know of, that owns its own GPS constellation simulator. This allows us to simulate adverse constellation configurations and signal strength conditions in a repeatable environment. Said differently, if I went out and stood in a relatively dense forest location at 10 a.m. my GPS receiver might work. If I went back to the same location at 10:00 p.m. it might not due to dozens of variables. With a simulator I can reproduce either condition and all the variables at will and improve the design to work in a greater variety of conditions.

ACR has always required GPS receiver and component manufacturers to manufacture to our specifications. However, without a GPS simulator we couldn’t tell whether the receivers we were getting actually met those specifications. GPS simulators aren’t cheap, but prior to the most recent Equipped to Survive tests, we identified this problem and addressed it by buying a simulator and by screening our production--I made ETSF aware of this before his test and I believe that is noted in the report you quoted from. To date WE ARE THE ONLY BEACON MANUFACTURER DOING THIS!!!!! Candidly, we find very few receivers out of spec… Knowing that we “inspect” what we “expect” I suspect that we receive the best out of respect. Seriously, we’ve been told by other suppliers, (of lanyard cordage, for example), that they ship us only goods that they know will pass our incoming inspection…because we’re allegedly their only customer that runs every lot through an accelerated UV chamber before accepting it into our raw materials warehouse… In other words you can only expect to get what you inspect. If you don't have a simulator, you can't inspect. Make sense?

The receiver in question was 1dBm beyond our specification. Most receivers are actually within 1dBm of the target sensitivity spec. Will they work in a storm? Define the storm and I’ll stick a beacon at the lowest end of our spec in the simulator and tell you. Chances are it will.

It sounds like in your last question you are asking for make and model of components and that information is proprietary. If you know enough about electronic components to understand the answer, and if it is really that important to your purchase decision, then I suggest you buy a beacon and take it apart… Then, if you are satisfied with the answer, go buy another one that you haven’t tampered with…

ACR has devoted itself to building the finest products of their kind for over 50 years. Our reputation speaks for itself. If you want the best, buy an ACR. I hope that wasn’t too commercial; but I believe in my product. Period.

The Hull Truth ROCKS!