How do Wireless Computers Work?

[Dransfield]

Does the display unti have some sort of radio frequency receiver in it, and the sensor have a radio
frequency pulse making thingy in it. If this is the case do the batteries run flat quicker than
wired ones while in sleep mode
(ie. its' radio's on all the time its parked in the shed)? I'm thinking of getting one, but don't
want to be changing the batteries a lot.

mark

[Bill]

Dransfield <m.thenmysurname@mail.com> wrote in message
news:n%zQa.23736$4O4.2512317@newsfep2-win.server.ntli.net...
> Does the display unti have some sort of radio frequency receiver in it,
and
> the sensor have a radio frequency pulse making thingy in it. If this is
the
> case do the batteries run flat quicker than wired ones while in sleep mode
> (ie. its' radio's on all the time its parked in the shed)? I'm thinking of getting one, but don't
> want to be changing the batteries a lot.

My cateye cordless is still going strong after two years without a battery change.

I don't think it is strictly wireless in that it is transmitting all the time. The magnet moving
across a coil generates an electro magenetic pulse which the receiver picks up. Or am I talking
complete balls? I am open to correction.

Bill

[Geoff Pearson]

"Bill" <barnacle54@hotmail.com> wrote in message
news:oUQQa.9516$ju6.187220@newsfep4-glfd.server.ntli.net...
>
> Dransfield <m.thenmysurname@mail.com> wrote in message
> news:n%zQa.23736$4O4.2512317@newsfep2-win.server.ntli.net...
> > Does the display unti have some sort of radio frequency receiver in it,
> and
> > the sensor have a radio frequency pulse making thingy in it. If this is
> the
> > case do the batteries run flat quicker than wired ones while in sleep
mode
> > (ie. its' radio's on all the time its parked in the shed)? I'm thinking
of
> > getting one, but don't want to be changing the batteries a lot.
>
>
> My cateye cordless is still going strong after two years without a battery change.
>
> I don't think it is strictly wireless in that it is transmitting all the time. The magnet moving
> across a coil generates an electro magenetic
pulse
> which the receiver picks up. Or am I talking complete balls? I am open
to
> correction.
>
> Bill
>
>
>

I've just changed the batteries in my £13 Equus for the first time after 4 years. It was so cheap
from the Edinburgh Bike Coop I couldn't not have it and I use it every day.

[Rory]

"Bill" <barnacle54@hotmail.com> wrote in message
news:<oUQQa.9516$ju6.187220@newsfep4-glfd.server.ntli.net>...
> Dransfield <m.thenmysurname@mail.com> wrote in message

> I don't think it is strictly wireless in that it is transmitting all the time. The magnet moving
> across a coil generates an electro magenetic pulse which the receiver picks up. Or am I talking
> complete balls? I am open to correction.

I dunno about the Catseye, but the Polar has a battery which will need to be replaced (its got an
orange LED as well, to help aligning it when installing).

[James Annan]

Dransfield wrote:
> Does the display unti have some sort of radio frequency receiver in it, and the sensor have a
> radio frequency pulse making thingy in it. If this is the case do the batteries run flat quicker
> than wired ones while in sleep mode
> (ie. its' radio's on all the time its parked in the shed)? I'm thinking of getting one, but don't
> want to be changing the batteries a lot.

The transmitter only transmits when the magnet passes the sensor, so it shouldn't go flat just
sitting around. The receiver usually (IME) needs to be manually switched on when you start riding,
to avoid the problem you describe. They aren't as reliable as wired computers, but I did run one
successfully for some time. I tried recently with a new bike but can't get a decent line-of-sight
route (brake boss in the way).

James

[Mike Quin]

James Annan <still_the_same_me@hotmail.com> writes:

> Dransfield wrote:
> > Does the display unti have some sort of radio frequency receiver in it, and the sensor have a
> > radio frequency pulse making thingy in it. If this is the case do the batteries run flat quicker
> > than wired ones while in sleep mode

> The transmitter only transmits when the magnet passes the sensor, so it shouldn't go flat just
> sitting around.

There is one exception to this: if you park the bike with the sensor and magnet lined up then the
transmitter will be left on, draining the battery.

--
Mike Quin <mike@elite.uk.com> :: Do you want to save before you quit? ::

[Tony W]

"Mike Quin" <mike@elite.uk.com> wrote in message news:87fzl5morq.fsf@oni.elite.uk.com...
> James Annan <still_the_same_me@hotmail.com> writes:
>
> > Dransfield wrote:
> > > Does the display unti have some sort of radio frequency receiver in
it, and
> > > the sensor have a radio frequency pulse making thingy in it. If this
is the
> > > case do the batteries run flat quicker than wired ones while in sleep
mode
>
> > The transmitter only transmits when the magnet passes the sensor, so it shouldn't go flat just
> > sitting around.
>
> There is one exception to this: if you park the bike with the sensor and magnet lined up then the
> transmitter will be left on, draining the battery.

Probably not as the pulse will be 'edge triggered' if the engineer who designed it was even half
competent.

T

[Mike Quin]

"Tony W" <tonyREMOVE@chapmore.co.uk> writes:

> "Mike Quin" <mike@elite.uk.com> wrote in message

> > There is one exception to this: if you park the bike with the sensor and magnet lined up then
> > the transmitter will be left on, draining the battery.

> Probably not as the pulse will be 'edge triggered' if the engineer who designed it was even half
> competent.

If I've still got the one I dismantled a while back lying around I'll check later, but if my memory
serves me correctly the sensor end of it consisted of a simple transmitter connected to the battery
by way of a reed switch. When the reed switch is closed by the magnet the transmitter is on.

--
Mike Quin <mike@elite.uk.com> :: Do you want to save before you quit? ::