PDA

View Full Version : Battery life and test on biased crossover



gerard
09-13-2007, 10:49 AM
Hello ,

Using by now a 9 vdc battery on my new 434x crossovers,
http://www.audioheritage.org/vbulletin/showthread.php?p=122118&highlight=biased#post122118

I would like to know the life expectancy of such a battery and how to test if the battery is ok for the nework or not !

I believe it depends on Vdc and also amperage of the battery . Should a 9 vdc lamp test would be ok ?

Gerard

Zilch
09-13-2007, 12:24 PM
The battery life is essentially equal to the shelf life, as the drain is miniscule.

Measure the battery voltage. If it's much below 9V, time for a new one.

I use the Lithium "Ultralife" 9V, which should be good for 10 years.

They are now required by code in residential smoke detectors here, and so are now more readily available.... :yes:

subwoof
09-13-2007, 02:11 PM
Do the typical "roadie" test on the 9V ( you can't always use test gear on a dark stage 3min before a show...)

Stick your tongue across the terminals. If nothing happens, toss it.

If you begin to speak wif a fubby tingawly feewing, it's good.

Kinda ruins the first sip of beer though...:)

sub

:cheers:

John W
09-13-2007, 02:20 PM
Has anyone else had a noisy alkaline battery in their charged coupled network?
At one time I had a charged coupled network on a pair of speakers in the bedroom. Occasionally, in the middle of the night with the amps and everything else powered off, I would hear an eerie gurgle-pop-click noise out of one speaker. I figured it may have been some residual charge in the power supply caps or something, so disconnected the speaker wires at bed time, but the noises reappeared. :eek:
I replaced the Duracell 9v battery and never heard it again.

Hoerninger
09-15-2007, 01:24 PM
Has anyone else had a noisy alkaline battery in their charged coupled network?

It is a very strange failure with a surprising solution. I would have estimated that one of the build in resistors is defective. The resistor and capacitor combination normally prevents any disturbing throughput from the battery to the speaker (timeconstant).

It is this kind of failure where I think:
Once is not once but twice is once too much.
(Einmal ist keinmal, aber zweimal ist einmal zu viel.)
____________
Peter

subwoof
09-15-2007, 09:08 PM
er sind ein dumkouph??

it's been 30+ years since german class but some things tend to stick.
unfortunately spelling isn't one of them...:)

Actually it's possible that a metal film resistor had a bond failure with one of it's caps ( a real common problem with dual transistor diff front ends ) but I really suspect that one cell in the 9V ( there are 6 total ) had a very bad contamination problem. That's why they leak when approaching the life's end.

Remember with a megohm resistance load, only a few electrons at a time are actually doing any work so it's idle time for the battery.

'weidersehen...

:cheers: