[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference noted::bicycle

Title: Bicycling
Notice:Bicycling for Fun
Moderator:JAMIN::WASSER
Created:Mon Apr 14 1986
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:3214
Total number of notes:31946

338.0. "Replacing Cateye Batteries." by PVAX::BELISLE () Mon Jun 08 1987 19:37

    I own a Cateye solar, the batteries not rechargerable anymore
    I'm would like to replace them, but, I know if I do I'll lose
    the memory (Odometer). Can anyone help me find a way of replacing
    the batteries without losing the memory??
    
    			Thanks for your time.
    				Mike
T.RTitleUserPersonal
Name
DateLines
338.1Silly procedures?SRFSUP::GOLDSMITHI salute Kernel Mode!Mon Jun 08 1987 20:128
    
    The way the batteries are placed in the back, it shouldn't be hard
    to rig something up to provide the unit power while you replace
    the batteries. However, if I remember right, the instructions ask
    you to place a piece of plastic between the batteries and remove
    the unit from the sun. Why? I don't know.
    
    							--- Neal
338.2Replace in sunlight...VIKING::WASSERJohn A. WasserTue Jun 09 1987 14:3313
	If your batteries won't charge havn't you already lost the
	settings and odometer???

	To maintain your odometer reading you should be able to
	change the battery while the solar cell is kept in full
	sunlight.  Since the cell is enough to charge the battery
	as well as run the display it may be enough to keep the
	memory active while the battery is changed.  

	If you loose the odometer reading you should remove the
	battery and cover the solar cell to reset everything
	properly.
338.3Hope this makes sense; I had success with it...EUREKA::REG_BMy personal name has expired ?Tue Jun 09 1987 14:4255
    
    	Long after (many months) the beeper quits and the LEDs go out
    there is still enough voltage to supply the logic, including the
    memory.   Don't give up on the old batteries yet !   I have one
    of those universal battery eliminater things that I have used to
    boost up an apparently dead cateye solar, which has then stayed
    alive for 2+ years (now that it lives on a south facing window sill
    when not on the bike).  I have managed to preserve the odo reading
    by using mini jumper leads (radio shack) that clip onto the battery
    connection clips.
    
    	This will be Fig #1, if it works:-
    
    
    			|--- +'ve	^
    	Battery		|		|
			|		Voltmeter
 	Eliminater	|		|
    			|		v
    			|--- -'ve
    
    	Use the voltmeter to identify +'ve and -'ve terminals and adjust
    for the minimum voltage that is above a pair of new cateye batteries.  
    I think this is 3 volts, you may have to go slightly higher.  Also
    identify the polarity of the cateye batteries and hook it up as
    in Fig #2, which I shall now try to draw.
    
	Fig #2    
    
    			|--- +'ve<------Milliammeter--->+'ve ---|
    	Battery		|					|
			|					|
 	Eliminater	|					| Cateye
    			|	  v Jumper Lead v		|
    			|--- -'ve------------------------'ve ---|
    

	You may also need a limiting resistor if the next step on the
    eliminater is so high that the batteries suck up more than about 50 ma. 

    	Its been a while since I did this (2+ years, see above comments),
    but I seem to remember that mine started out at 100 (maybe 150)
    ma and quickly dropped to 20ma or so.  These readings will depend
    on the output voltage and impedence of the particular supply you
    use, as well as the state of the batteries you are trying to boost.

    	If the LEDs come up and the odo is still intact leave it on
    a trickle charge, say overnight.  If it still won't hold a charge
    them the batteries are shot and will have to be replaced.  Leave
    the clips connected, reduce the output until the ammeter shows ~0
    charge, replace the batteries, disconnect the charger and you're
    all set.

    	Reg
    
338.4338.3 (.1)EUREKA::REG_BMy personal name has expired ?Tue Jun 09 1987 16:5921
    
    	re .3	Following a couple of mail messages with Mike Belisle,
    who posted .0, and having given it a bit more thought, it seems
    a couple of additions should be made.

    	If the charger source you are using has an open circuit voltage
    greater than about 5 volts then it is probably unregulated and only
    stays down at ~ 3 volts when there is a battery hanging on it to
    act as a zener diode.  Most battery chargers are not intended for
    use as regulated supplies, without the capacitive load of a battery
    there may be a very large 50/60 Hz ripple that could corrupt the
    memory and/or destroy the cateye's logic.  There is at least some
    risk that the cateye could be blown by supporting it with an
    unregulated supply while changing the batteries.  If you have any
    doubts about the regulation of the power supply you plan to use
    its probably safest and worth the minor hassle to rig up a couple
    of flashlight cells in series (~ 1.5 v each) and clip those in while
    changing the rechargeables.

    	Reg
    
338.5APOLLO::WORRELLTue Jun 09 1987 17:3813
    re .1
    
    >the batteries. However, if I remember right, the instructions ask
    >you to place a piece of plastic between the batteries and remove
    >the unit from the sun. Why? I don't know.
    
    The battery is probably required to regulate the voltage supplied
    by the solar cell to prevent what .4 describes.
    
    I can't guess what the plastic is supposed to do.
    
    Glen
           
338.6Piece of plastic?NOVA::FISHERWed Jun 10 1987 13:487
    there is a problem which sometimes occurs when inserting/removing
    batteries without using the piece of plastic.  The computer emits
    a long beep and the display has all of its lcds turned on.  From
    this I would assume that it has been zapped by a spike or two of
    electricity.  Trying again usually solves the problem.
    
    ed
338.7Didja keep your plastic, Vern?AMUN::CRITZYa know what I mean, VernWed Jun 10 1987 13:5211
    	The infamous piece of plastic comes with a new Cateye,
    	inserted between the batteries. I remember reading
    	(last Xmas in the instructions) that the user was
    	supposed to keep the piece of plastic just for
    	the reasons previously stated.
    
    	Because Nashbar is no longer carrying the Cateye I,
    	I'm going with the micro. Hopefull (if I remember),
    	I'll give my impressions of it later.
    
    	Scott
338.8Resetting your cateye and the year to date presentation...EUREKA::REG_BMy personal name has expired ?Wed Jun 10 1987 15:0016
    re .(? ~5)  The little piece of plastic seems to be for a couple
    of reasons:-  a) it keeps the batteries separated, i.e. disconnected
    during storage and shipment, so they retain at least their initial
    charge   b) it provides a fairly "clean" power up switch.  c) it
    can be used for "power up reset", as described earlier.  If you
    lose it and need one, a reasonable substitute can be made from a strip
    of overhead transparency, about 1/4 x 1 inch.   This provides some
    entertainment when the boss puts up a presentation and says, 
    "Oh, what happened to the corner of this one ?, must be mice" 

    	Anyway, Mike's original problem was to replace the batteries
    *WITHOUT* losing the odo reading, i.e. he needs to keep the circuits
    alive.

    	Reg
    
338.9Use Backup!ISBG::MILLERMarketing, the oldest professionThu Jun 11 1987 16:014
    I may be way out of line here with this idea, but why can't you
    just take the Cateye and back it up onto a uVAX-II until you get
    the new batteries in place, and then down-line load it with the
    data you backed up?
338.10Is this the sailing conference, or what ?EUREKA::REG_BN_ew E_ngland C_onservatory makes disks ?, no way !Thu Jun 11 1987 16:414
    re .miller;Gary	'coz it don't got a MIDI port !
    
    	Reg
    
338.11For $8.50 you won't have to change battaries so often.TSG::HATCHERTue Jun 16 1987 17:468
    Latest Nashbar catalog shows an ordinary kids nightlight (the kind
    you can buy for about $2) with a kind of sling under it to hold
    the unit.  It says
    it's the perfect way to keep your CatEye charged.  They want $8.50
    for it.  Sounds like a ripoff.  We're in the wrong business.
    
    bob
    
338.12NEXUS::GORTMAKERthe GortThu Jun 18 1987 02:323
    re.9 & .10
    Use the optional 19.2k baud modem and you can bypass the port...8-)