Could anybody please tell me how many watts are used by the ProMark2s?

Thanks! :)

Given that I get about 6.5 hours out of a pair of 1600mah batteries, it must be somewhere around 250ma. At 1.2v per cell, that comes to about 0.6w, if I did all the arithmetic right. (This doesn't take into account any difference between the cutoff voltage of the PM2 and the cutoff used in rating the batteries, if any.)

I just wondered because the pamphlet that came with the SLA batteries gave a table of estimated running times for various products based upon their wattage. 20 to 40 hours is what is listed for devices burning 2 to 10 watts. The proof will be in the actual run times I expect.

The units are smaller than I had imagined - see photo below with Magellan 330 alongside for scale. They weigh 3.0 lbs each and fit perfectly into the Ashtech PM2 carrying bags.

Hat's off to Jeff Austin for the suggestion and link!

start one running and let us know when it dies!

As soon as they get here, and I make the necessary modification to the external power adapter, I hope to do just that while also keeping track of the tempratures. Then we'll see if they're ORGI material ;)

When I asked I was told to look in the books and spec sheets. I was not able to find it in the books and spec sheets.

I think Mike's advice was the best. Run it till it dies and then you know the answer.

I can tell you about my little experiments using a ProMark2 sitting on my bookshelf. Now guys I know it's nice weather in my cube. You don't have to tell me. This boy knows how to read a post and listen to a gripe.

On Wednesday with a set of new AA's inside I started it at 8:50 AM and it quit at 5:24 PM.

On Friday with a set of new AA's inside and a 9 volt transitor battery connected to the outside I started it at 7:12 AM and it quit at 5:27 PM.

I'm just tinkering and hoping for spring.

Modified By Phil athome on 2/9/2002 at 2:58 PM

Hi Phil,

Thanks for the reply.

Boy, I would think that somebody at Ashtech could answer this question. The manuals don't indicate the wattage rating.

What is eating up all the power? The Locus units were reported to use less than 1 watt.

Design feature to consider: Energy saving mode - automatically powers down graphics when collecting data; a touch of the power button brings graphics screen back to life. A longer held touch powers unit off completely.

Another design feature to consider: Make the external power adapter (Magellan part no. 730275) able to receive the terminal of the 110454 antenna instead of having the customers attempt at making their own costly and possibly risky modifications.

Kelly Bellis wrote:

Another design feature to consider: Make the external power adapter (Magellan part no. 730275) able to receive the terminal of the 110454 antenna instead of having the customers attempt at making their own costly and possibly risky modifications.

It looks to me as though the idea of reusing the Magellan form factor for the PM2 was a bit of an afterthought. The design of the connectors pretty clearly didn't anticipate an external antenna, as the antenna connector diameter is too large to provide comfortable spacing from the power contacts.

Modifying the Magellan power connector would require redesigning the attachment screw; my guess is that the relatively small number of PM2 units relative to the Magellan quantities doesn't justify the redesign and retooling that would be required.

Wonder how Ashtech is getting the antenna through the external power supplies shown below?

I expect they've done just what we did: drilled out the attachment screw hole to accommodate the antenna plug. I'm curious to know whether they used redesigned power contacts to provide more clearance.

Another "experimenter" who contacted me had a great idea: he slipped a piece of heat-shrink tubing over the antenna plug to prevent accidental contact. I'm going to give that one a try, too.