How to get the cycle computer magnet closer to the sensor

General cycling advice ( NOT technical ! )
Grandad
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Joined: 22 Nov 2007, 12:22am
Location: Kent

Re: How to get the cycle computer magnet closer to the sensor

Post by Grandad »

For those not adept at sea-talk: RTFM = Read The Manual.

Another version - "if all else fails read the manual"
GranvilleThomas
Posts: 139
Joined: 1 Apr 2015, 9:58am
Location: Caerphilly

Re: How to get the cycle computer magnet closer to the sensor

Post by GranvilleThomas »

sailorp wrote:One thing to check Is the vertical alignment of the magnet with sensor, as well as the horizontal distance.
I recently changed to a new wireless computer (BBB) having used Cateyes previously.
I could not get the BBB computer to work, even with a spacing of 2mm from magnet to sensor, (with sensor angled in towards the spokes to achieve minimum spacing).
That is until I noticed that the sensor had a small white dot on the side.
This dot turned out to be the position of the magnetic pick-up inside the sensor plastic housing.
Once the dot and the magnet were in vertical alignment, rather than vertically displaced, everything worked fine, even with the magnet at more than 5mm horizontally from the sensor.
So try moving the sensor (or magnet) up and down a few mm?
Moral: RTFM, as we say at sea.
For those not adept at sea-talk: RTFM = Read The <FFE> Manual.


Very good advice!

Funny enough I was going to raise this aspect of my particular installation as the Aldi computer manual states:

"Ensure that the magnet passes the sensor at a distance of approx. 0.08" (2 mm) at the arrowmark on the sensor (see Fig. D)."

Now I interpreted this as meaning that the spoke magnet should pass the arrowmark on the sensor so that the arrowmark is in the middle of the magnet?

However if you set it up like this then you get erratic readings when in fact the top edge of the magnet has to be in line with the arrowmark on the sensor for it to work correctly ie centre of magnet 5mm below arrowmark.

I found this out by trial and error and just as you suggested I moved the magnet up and down a few mm to determine the optimum position and I would absolutely suggest doing this if you have problems before trying anything else.

So yes RTFM but don't forget, not all manuals are created equal. Being a radio ham, I know this all too well as the market is flooded with inexpensive Chinese equipment and very good value for money it is mainly, but some of the English translations of manuals for such equipment leave a lot to be desired and a lot can get lost in the translation!

I was determined to get the Aldi wireless computer to work properly and it was a challenge that proved to be interesting to me, but this was the first wireless device I have tried and on reflection I think I would prefer a wired computer simply because there is only one battery to purchase (tight Celt!) and they seem a lot less critical around the magnet/sensor interface.

I have used wired computers ever since the first Avocet that I purchased in the 80's and with a little imagination the wires can be routed to be unobtrusive and aesthetically pleasing to even the most discerning eye, well that is in my humble opinion.
simonhill
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Joined: 13 Jan 2007, 11:28am
Location: Essex

Re: How to get the cycle computer magnet closer to the sensor

Post by simonhill »

Re the two batteries in a wireless set up.

Two batteries are supplied with a new purchase (well they are in all my Cateyes)..

When the display starts to get feint (or cuts out in cold weather), its time for new battery (note battery).

Take old battery out of sensor unit and put it in the display unit - it has plenty of life left so can continue to be used .

Put a new battery in sensor unit. Two reasons, it uses less power and its not so obvious if battery is flat in that unit.

I do this and only need to use one battery every year or so. Its been good for 8,000 plus kms.
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freiston
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Joined: 6 Oct 2013, 10:20am
Location: Coventry

Re: How to get the cycle computer magnet closer to the sensor

Post by freiston »

GranvilleThomas wrote:<snip>So yes RTFM but don't forget, not all manuals are created equal. Being a radio ham, I know this all too well as the market is flooded with inexpensive Chinese equipment and very good value for money it is mainly, but some of the English translations of manuals for such equipment leave a lot to be desired and a lot can get lost in the translation!

I was determined to get the Aldi wireless computer to work properly and it was a challenge that proved to be interesting to me, but this was the first wireless device I have tried and on reflection I think I would prefer a wired computer simply because there is only one battery to purchase (tight Celt!) and they seem a lot less critical around the magnet/sensor interface.<snip>
The other good thing about wired computers is that they don't suffer interference from mobile phones. I changed from a wireless Cateye to a wired Cateye for this reason: when my phone was in my bar bag or mounted on my handlebar, the wireless computer would sometimes give me speeds of 6mph when I knew it to be closer to 20mph and would usually give me a maximum of around 60mph (when I knew it to be closer to 20 mph :wink: ). Other readings such as distance were out too.

A small digression re. translation of manuals - I have a computer/media box remote control that doubles as a mouse by pointing it at the screen and moving it; the remote control unit is called an "air mouse". Half way through the manual, they stop calling it an air mouse and call it a flying squirrel instead :lol:
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)
GranvilleThomas
Posts: 139
Joined: 1 Apr 2015, 9:58am
Location: Caerphilly

Re: How to get the cycle computer magnet closer to the sensor

Post by GranvilleThomas »

Flying squirrel, ha, ha, I think that's hilarious. :lol: If you want some funny translations then look no further than Wales. Take a look at these road signs that were badly translated into Welsh on the 'cyclingwales' website: :

https://www.cyclingwales.co.uk/badlytranslated.html


I have also experienced the interference problem with wireless computers. Not with my mobile as this is usually in my rear pocket but with led lights.

I have had to move the external battery for the front light into one of the bottle cages and re-route the cable before the Aldi computer would work at all when the light was on and the rear MagicShine MJ 818 light produces so much 'RF hash' that it renders inoperable any radio communications equipment that I sometimes like to take with me when cycling at night.

Also the Vetta HR1000 heart rate monitor computer that has a chest strap to wirelessly send pulse rate readings to the display unit on the handlebars would inform me that my pulse rate was 300 BPM or so if I happened to venture anywhere near an electricity pylon whilst on my travels! :lol:
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