On Saturday, November 28, 2020 at 8:30:05 PM UTC-8, Ian Molesworth wrote:
At 16:59 26 November 2020, AS wrote:
On Thursday, November 26, 2020 at 11:19:57 AM UTC-5,

w=
rote:
I have used such a battery since July. Works just fine for me in
my ASG
3=
2 Mi with lots of electronic stuff.=20
=20
/Robert

So there is already some operational experience with this type of
batteries=
, which is good to hear. The warnings about the initially high
voltage of
1=
6+V is well taken. I checked the spec's of the stuff I have on and
behind
m=
y panel and most of it is limited to only 15V.=20
That would lead me to more follow-up questions for the experts:
- what would happen if this battery was charged with only 15V?
=20
- if the above is not advisable, would the use of an electronic
voltage
reg=
ulator like this one be an option?
https://vetco.net/products/dc-dc-adj...-down-voltage-
regulator-mod=
ule-with-volt-meter-d92?
gclid=3DCj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EE=
nZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
- I am not familiar with this type of electronics but reading the
specifica=
tions of it, I see a 'Ripple Frequency' of 150kHz on the output.
Could
that=
mess up the electronics?

Thanks for any constructive replies.

Uli
'AS'


If you are going to put a 'power limiter' in the supply line then use
something linear not switching. Linear supplies dump extra power in
the form of heat. Switching power supplies make electrical noise
unless they are properly constructed and shielded ( ie expensive )
Knocking up a power regulator for this type of applicaion is barely
worth the effort.

One or even two simple diodes placed in series with the main
positive feed to those instruments rated at a lower maximum
voltage provides a safe and secure way to simply drop the voltage
into that device. As a side effect, you get additional reverse polarity
protection to your instruments!

for most instruments, a 1N4007 1 Amp diode would suffice. it drops
about 0.7v at very small currents and 1v at its maximum rating of 1
Amp.

A glass screen device might need a diode rated a little higher at say
2 or 3 Amps.

It might just be simpler to put a big diode rated at 20 amps or so in
line with the battery. A STTH20R04 will easily handle that sort of
current and give you an overall 0.6v minimum drop up to 1.5 drop
at 20 Amps.

These things are pennies even in single quantities.

Any passive device that drops voltage will be inefficient and do it by converting the power into heat. Low noise switching regulators do not need to be expensive. Here is but one example:
https://www.analog.com/en/products/p...gulators.html#
https://www.analog.com/en/parametricsearch/11001#/d=5351|5573|5574|5349|5358|5345|5575|5362|5589|s3| s5
These devices also provide current limiting as a bonus

Tom