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It didn't. I'm gonna check all signals with a scope. Also, I may tryAha! This is something I'm not doing. I keep CE# low all the time.
Let me know if it works out!
I have a number of power transformers I have picked up and am looking
to use one for a specific application. Most are completely unmarked.
It is generally easy enough to determine the pinnings through
continuity and resistance checks, likewise by connecting it to a
source, the voltages are easily determined. What I am struggling with
is how to determine the current it is designed or rated for, any
suggestions?
Thanks,
Sean Mathias
Actually, 'equalizer' charging goes back to Navy submarine battery days.William P.N. Smith <wpns@compusmiths.com> wrote in message
news:<fsj0ivsemhu001dlbom58d9cvqdba1dn6d@4ax.com>...
I've seen others recommend something similar to the first stage, but
they then apply that higher voltage once a week or so during float to
"equalize" charge. I'm not sure exactly what's unequal that requires
this... I do realize that not all cells will be identical but I'm not
sure how these differences are overcome by overcharging, as all the
currents in the series string are guaranteed to be identical.
And if at all possible I'd like to see these recommendations rise from
"old wives tales" to actual documentation by the battery makers. (As
opposed to sales hype by the charger makers!)
Here is the official word. Direct from Click and Clack of Car Talk fame:speaking of lead acid battery old wives tales, the tale about not leaving a
lead acid battery on concrete, fact or fiction??
I have a couple of these I'd like to use but I can't find the pinouts
for them. Specifically, they are Fujitsu MB81464-10, date code looks
like 1986. If you have data, please email, thanks!
--
eric
Hmmm... Very close, but doesn't show which pins are VSS and VDD.
"Mark (UK)" <jumbos.bazzar@btopenworld.com> wrote in message news:<3F22CE30.EF6968ED@btopenworld.com>...
Hiya!
I don't have a datasheet, but look here:
http://www.spies.com/~arcade/schematics/PDF/HotRodSchem.pdf
on page 6, this arcade PCB uses them, and shows what pin connects to
what.
Yours, Mark.
Eric Williams wrote:
I have a couple of these I'd like to use but I can't find the pinouts
for them. Specifically, they are Fujitsu MB81464-10, date code looks
like 1986. If you have data, please email, thanks!
--
eric
If you have dual in line:I have a couple of these I'd like to use but I can't find the pinouts
for them. Specifically, they are Fujitsu MB81464-10, date code looks
like 1986. If you have data, please email, thanks!
--
eric
(Please post followups or tech enquires to the newsgroup)I have a couple of these I'd like to use but I can't find the pinouts
for them. Specifically, they are Fujitsu MB81464-10, date code looks
like 1986. If you have data, please email, thanks!
Robbie
[Image]
PIC16C505 ?Hi!
I have unknown chip on board.
We can say about it few points:
- that is 14 pin DIP package
- its programable chip, because has a revision number drawn on sticker
- someone remove any characters and type marks from it.
- production date is (95-98 )
I have a question: what tape of chip can it be ?
I will be very grateful for any answer.
Jerzy Hoffman
"Fred B. McGalliard" <frederick.b.mcgalliard@boeing.com> wrote:
This is generally done with a low value resistor shunting a low voltage
meter.
Speaking of shunts, what's a good source for them? I need to turn 'a
couple of amps peak' into {2.5,7.5,25} mV
Thanks!
--
William Smith wpns@compusmiths.com N1JBJ@amsat.org
ComputerSmiths Consulting, Inc. www.compusmiths.com
The OP stated "a couple of amps", so he's not looking for theIn alt.solar.photovoltaic
ehsjr@bellatlantic.net wrote:
: "William P.N. Smith" wrote:
:> "Fred B. McGalliard" <frederick.b.mcgalliard@boeing.com> wrote:
:> >This is generally done with a low value resistor shunting a low voltage
:> >meter.
:
:> Speaking of shunts, what's a good source for them? I need to turn 'a
:> couple of amps peak' into {2.5,7.5,25} mV
:
: You can make your own. Run a known current through a bare piece
: of wire. Attach one voltmeter lead to one end of the wire and
: slide the other lead along the wire until you read the voltage
: you are after.
To make one that can be used in the battery
circuit it would probably need a heavy piece of
brass or copper for the shunt.
Large industrial shunts that allow a remote
meter movement without running the heavy wire to
the meter uses what appears to be a square bar
of brass with a cross section of almost an inch
and about 4 inches long.
The meter wires attach to two screws about
two inches apart on the brass bar.
This allows a 500 milliamp meter movement
to read amperage up to 800 amps.
It could be done with any solid brass
object that could be placed in series between
the batteries and the load (copper would probably
corrode but might work), and with the meter wires
just attached a couple of inches apart on the shunt,
vary the load and interpret what the meter movement reads.
Safety goggles would be a good idea.
Joe Fischer
--
3
"Pull-an-idea-out-of-thin-air" guess:hi anyone,
i have a small electronic component that i can't identify. it looks like
a typical 1n4001 diode, similar size and shape with axial leads, but
there's no marking on it except for a single yellow stripe at the
midpoint.
i got a switch mode power supply and it has about a dozen of these
things in the circuit.
what are they?
thanx, louie
Robbie Banks wrote:
Robbie
[Image]
Robbie, this is not a Binaries newsgroup. You need to post it to
news:alt.binaries.schematics.electronic by attaching it as a GIF, JPEG,
or other common image file. You can post a message here giving the name
of the post on A.B.S.E, but mst of the regulars read both groups. If
post a binary file here, most people will never see it.
--
Michael A. Terrell
Central Florida
Probably not.What would be a simple, but effective circuit
to completely discharge them without any
damage to them? I got a bunch of them, and
now they all have varying capacities.
I'm thinking about an 1N4001 in series with
a 33 ohm, which would drain them to about
0.7V, but I have a feeling that might be a
little too much.
Would a couple of discharge / recharge cycle
help to regain some of the lost capacity?
Most commercial shunts are marked to be used with a 50 millivolt meter.In alt.solar.photovoltaic
Lizard Blizzard <NOSPAM@rsccd.org> wrote:
: Joe Fischer wrote:
:> The meter wires attach to two screws about
:> two inches apart on the brass bar.
:> This allows a 500 milliamp meter movement
:> to read amperage up to 800 amps.
:
: Umm, first off, he said 'a couple of amps', NOT Hoover Dam!
That was a big shunt, the principle is the same.
: Second, you didn't mean 500 mA meter movement, right? The usual meter
: for this is a 50 mV, not mA.
I have had meter movements that were 100 milliamps
full scale, 500, and 1000.
There are no volt meter movements, all volt meters
are one amp (or less) meter movements in series with a
resistor. I think a one amp movement requires a 55000
ohm resistor to make a DC volt meter with about a 100 volt
full scale.
This is just from memory from 1951 when I made
my first volt meter and found that being able to
interpret the reading is just as important as
having a precision meter.
Joe Fischer
--
3
Does anyone know any easily obtainable (read Radio Shack ;-)There is no real benefit in going below around 0.9V/cell or so.
Of course!!You imply that you mean doing this per cell.
This isn't a battery pack, these are mostly standalone C's and D's.If this is so, it's safe, but if you do it with a battery, you
must observe individual cell voltages, and check that none approach
0V. (going to 0V isn't too bad, going below is)
This might be a good idea, but I consider it too much hassle ;-)What you can do is to put them all in series, give a constant current
charge
of C/10 for 20 hours or so, to make sure they are all fully charged.
Then discharge in series, checking every 50mah or so, and thereby sort the
cells by capacity, taking the lowest capacity ones out first.
This lets you roughly match sets of cells.
Just checking..."Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:bggfob$hv4$1$8302bc10@news.demon.co.uk...
There is no real benefit in going below around 0.9V/cell or so.
Does anyone know any easily obtainable (read Radio Shack ;-)
diode with a Vf of 0.85 - 0.9V?
You imply that you mean doing this per cell.
Of course!!
It's actually not too bad.If this is so, it's safe, but if you do it with a battery, you
must observe individual cell voltages, and check that none approach
0V. (going to 0V isn't too bad, going below is)
This isn't a battery pack, these are mostly standalone C's and D's.
What you can do is to put them all in series, give a constant current
charge
of C/10 for 20 hours or so, to make sure they are all fully charged.
Then discharge in series, checking every 50mah or so, and thereby sort the
cells by capacity, taking the lowest capacity ones out first.
This lets you roughly match sets of cells.
This might be a good idea, but I consider it too much hassle ;-)
If you'r just doing this a couple of times, then going all the wayI just want to rig a battery holder to make it a discharger, put
the batteries in, remove them a day later, put them in the charger
(which stops charging when the battery is full) and repeat this
cycle a couple of times.
Nope.The thing I wasn't sure whether discharging it to 0.7V or so, and
keeping it there for a few hours would have any adverse consequence.