I've heard that the Promark2, with the INTERNAL batteries, will not drive the external antenna, or at best, won't run it for very long at all.

Does anyone know if this is true or not?

John,
I suspect that story came from somebody with a financial interest in selling you something else !
There are many threads available on this board using search under batteries which deal with battery life under varying ambient temperatures etc.
I have never heard of anybody being unable to power the antenna at all ! In fact in a reasonable temperature of 65F we have run them using unauthorised antenna cable extensions of 7m for six hours on ordinary AA's.Ex Locus users seem to a bit disappointed with battery life but once you've carried PM2's on a pole for a couple of hours I for one go for the weight advantage !

John,

You may be referring to the use of
Re-charable Nicad batteries. While these type of batteries are more enviromentally friendly, they don't work very well for this application.

Thales technical Support has confirmed
using re-chargable batteries with the PM2 will cause problems. These problems don't surface during the field data collection, the PM2 appears to work OK in the field, but adverse problems can occur becomming noticable during the data processing.

Not all the Vectors will process. Examining the Vector's Residual plots will indicate repeated loss of SV lock during data collection.

The re-charable batteries do not maintain sufficient amperage to drive the PM2 external antenna. Re-chargable batteries ramp down very quickly.

Thales recommends using only akaline
double AA batteries including the Duracell and Energizer brand consumer batteries.

Everytime I check they look better and better

Everytime I hear something bad about them & check . . . they look better and better

John,

Like NIKE says "Just do it".

John,
the internal batteries work fine for "driving" the antenae on the ProMark2's.
The only reason there possibly would be a shortage of battery power would be if you were to try to use an antenae cable which is substantially longer than the cable supplied with your units. That seems to really cut down on the available power to the antenae itself. In that case, you would want to hook up an external power source.
I am running 4 ProMark2's on a regular bases and have never experienced what you are describing with the supplied cables.
http://www.moeland.com/moelandgps.htm


Mike Moe
Modified By Mike Moe on 2/22/2003 at 10:06 AM

I thought I had a similar problem - turned out to be the cable end connector as it entered the antenna - if you open up the cable end you'll find its a wire end sort of friction fit - I repaired one and bought a spare - much more carefull about coiling up the cable after seing the way its made. alkalines or the super alkalines last all day, or almost even when very cold - at least thats been my experience north of chicago.