The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
From: Harald Milz
Subject: Re: 9V bat ->2AA + switcher ?
Date: 4 Dec 2002 19:41:45 GMT
NNTP-Posting-Date: 4 Dec 2002 19:41:45 GMT
X-Pgp-Public-Key: http://www.muc.de/~hm/pgp.asc or finger hm [at] muc.de
X-Nospam: I do not want to receive unsolicited advertising!
X-Reply-To: Replies to the From address will go to /dev/null. Use Reply-To.
User-Agent: tin/1.4.2-20000205 ("Possession") (UNIX) (Linux/2.4.18 (i586))
Phil Seakins wrote:
> The relationship between current and voltage in these circumstances is
> inverse. In fact, it's the same relationship as AC via step-up or
> step-down transformers.
That said, for a given battery chemistry you get a certain amount of
mWh (capacity) per volume. A 9V battery is also only 6 1.5V cells in
series. If you use two 1.5V cells which together have the same volume
as a 9V battery, you get about the same gross capacity, but given the
efficiency of the step-up converter which is < 1 you actually _lose_
capacity. So for primary cells you don't gain a lot. For rechargables
it is different - AA NiMH cells are now available at 2000 mAh while 9V
(actually 7.2V in most cases, rarely 8.4V) batteries are still below ~
250 mAh which is less than half of the AA / converter capacity.
You're being followed. Cut out the hanky-panky for a few days.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup