Does anyone use the Garmin speed sensor outdoors? Is it of any use?

Galego

I known it is handy when indoors in the turbo trainer but outdoors.....Is it really needed in Ireland?

smacl

Galego wrote: »

I known it is handy when indoors in the turbo trainer but outdoors.....Is it really needed in Ireland?

If you rely solely on GPS you can lose lock as you go into a forested area which might take a few seconds to get back or longer under some circumstances. You can also get occasional spikes in your data due to multipath where you pick up a signal bounced off a nearby tall object. So while you don't need the speed sensor, you get cleaner and more complete data when you use it.

crosstownk

smacl wrote: »

If you rely solely on GPS you can lose lock as you go into a forested area which might take a few seconds to get back or longer under some circumstances. You can also get occasional spikes in your data due to multipath where you pick up a signal bounced off a nearby tall object. So while you don't need the speed sensor, you get cleaner and more complete data when you use it.

I agree with this.

For example, on my commute when I pass under the trees in Drumcondra at the bishops palace the speed reading on GPS drops by 5 or 6 km/h due to the tree cover. I've also noticed similar in other shaded areas. It's no biggie but it does annoy me so I now use speed sensors.

godtabh

I use it all the time and hate when I leave it on the turbo wheel. It picks up acceleration quicker and is more accurate than gps.

triggermortis

I use one all the time too. Can't understand why I still get auto pause sometimes when I'm still moving, but it always happens in a couple of particular spots so it must be gps interference of some kind

stecleary

triggermortis wrote: »

I use one all the time too. Can't understand why I still get auto pause sometimes when I'm still moving, but it always happens in a couple of particular spots so it must be gps interference of some kind

have you got auto pause set too high? i set mine to something like 5kmh so it only kicks in when im near stopped

triggermortis

stecleary wrote: »

have you got auto pause set too high? i set mine to something like 5kmh so it only kicks in when im near stopped

I didn't realise there was a setting for this, I'll look into it.
There's a spot as I cross over the M1 towards Ballyboughall that the auto pause always kicks in for a second, as well another place that I can't remember where now. I know I'm slow but I'm not going that slow at this point..

captain_boycott

depending on your Garmin device, it may also support glonass. If so, turn it on to get addition satellites (Russian as well as US GPS system). It may be disabled by default as it consumes more battery.

Luxman

captain_boycott wrote: »

depending on your Garmin device, it may also support glonass. If so, turn it on to get addition satellites (Russian as well as US GPS system). It may be disabled by default as it consumes more battery.

Is it more accurate to have more satellites or just a gimmick that it acquires connection more quickly?

smacl

Luxman wrote: »

Is it more accurate to have more satellites or just a gimmick that it acquires connection more quickly?

Broadly speaking, the more observable (i.e. visible by direct line of sight) satellites available to a GPS, the better accuracy it can achieve. This improves further with augmentation systems such as WAAS, but is limited by the total number of channels available in the receiver. I'd expect the GPS on the Garmin for example to be much better than that on your phone, though haven't ever checked this.