Help! Universal Adaptor Question

[Annie]

Hi, I just bought a portable handheld tv, the Casio TV-970, and want to
purchase a universal adaptor for it.
The universal adaptors I've seen have different ratings, from 350mA, to over
1000mA.
The specifications on the user guide says that it runs on 6 volts, and the
power consumption is approiximately 3.1W.

How much mA do I need?

Regards,
Patrick

 

[Lord Garth]

"Annie" <afritz@aol.com> wrote in message
news:d3so54$hfl$1@reader01.singnet.com.sg...

Hi, I just bought a portable handheld tv, the Casio TV-970, and want to
purchase a universal adaptor for it.
The universal adaptors I've seen have different ratings, from 350mA, to
over
1000mA.
The specifications on the user guide says that it runs on 6 volts, and the
power consumption is approiximately 3.1W.

How much mA do I need?

Regards,
Patrick

P=V*I so I=P/V

P is power in Watts
V is voltage
I is current in Amps (1000mA=1A)

Watch the polarity!!!!

You can use a power adapter with more current but be warned that most
of these cheap power supplies are half wave rectifiers with a capacitor.
This means they are NOT voltage regulated. Measure one that is not
loaded and verify that the output voltage is higher than stated.

 

[Phil Allison]

"Annie" <afritz@aol.com>

Hi, I just bought a portable handheld tv, the Casio TV-970, and want to
purchase a universal adaptor for it.

** When analogue TV is switched off in 2008 - that toy will cease to
function.

The universal adaptors I've seen have different ratings, from 350mA, to
over 1000mA.
The specifications on the user guide says that it runs on 6 volts, and the
power consumption is approiximately 3.1W.

How much mA do I need?

** You need an 700 - 800mA rated **regulated** adaptor of the correct
polarity.

Buy the Casio one if you have any sense.





.............. Phil

 

[Eric]

You might still be able to watch via a VCR (if they still have VCR's in
2008)

Buy the way wouldn't the "TV digit box" have a analogue output so you can
still use the old analogue TV's until they suff it.




"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3ceb82F6m8rovU1@individual.net...

"Annie" <afritz@aol.com>

Hi, I just bought a portable handheld tv, the Casio TV-970, and want to
purchase a universal adaptor for it.

** When analogue TV is switched off in 2008 - that toy will cease to
function.

 

[Phil Allison]

"Eric" <haha@clear.i.never.see.junk.mail.com> wrote in message
news:4261fa3a$1@clear.net.nz...

You might still be able to watch via a VCR (if they still have VCR's in
2008)

** Sure - just shove one in your back pocket.

Buy the way wouldn't the "TV digit box" have a analogue output so you can
still use the old analogue TV's until they suff it.

** That Casio is a tiny, portable TV - you sheep shagging, top posting,
anencephalic.

It will cease to function as a portable !!!!



............. Phil

 

[Ed ()]

it's 500mA btw, buy a $20 digital multimeter then you can measure things
yourself.

"Lord Garth" <LGarth@Tantalus.net> wrote in message
news:mhm8e.2299$zq4.945@newssvr11.news.prodigy.com...
:
: "Annie" <afritz@aol.com> wrote in message
: news:d3so54$hfl$1@reader01.singnet.com.sg...
: > Hi, I just bought a portable handheld tv, the Casio TV-970, and want
to
: > purchase a universal adaptor for it.
: > The universal adaptors I've seen have different ratings, from 350mA,
to
: over
: > 1000mA.
: > The specifications on the user guide says that it runs on 6 volts,
and the
: > power consumption is approiximately 3.1W.
: >
: > How much mA do I need?
: >
: > Regards,
: > Patrick
:
:
: P=V*I so I=P/V
:
: P is power in Watts
: V is voltage
: I is current in Amps (1000mA=1A)
:
: Watch the polarity!!!!
:
: You can use a power adapter with more current but be warned that most
: of these cheap power supplies are half wave rectifiers with a
capacitor.
: This means they are NOT voltage regulated. Measure one that is not
: loaded and verify that the output voltage is higher than stated.
:
:
:
:

 

[Brian Goldsmith]

"Lord Garth" <LGarth@Tantalus.net> wrote


You can use a power adapter with more current but be warned that most
of these cheap power supplies are half wave rectifiers with a capacitor.
This means they are NOT voltage regulated.

*** Er,where did this nonsense come from.Half wave???????????????

Brian Goldsmith.

 

[Lord Garth]

"Brian Goldsmith" <brian.goldsmith@nospam.echo1.com.au> wrote in message
news:JDu8e.14670$5F3.13180@news-server.bigpond.net.au...

"Lord Garth" <LGarth@Tantalus.net> wrote


You can use a power adapter with more current but be warned that most
of these cheap power supplies are half wave rectifiers with a capacitor.
This means they are NOT voltage regulated.

*** Er,where did this nonsense come from.Half wave???????????????

Brian Goldsmith.

Some have a half wave rectifier some have full wave, almost all are crap

and none of that type are voltage regulated. Cut some open and look or
just scope the output. The point is that he should not use that type.

 

[Phil Allison]

"Lord Garth"

"Brian Goldsmith"

You can use a power adapter with more current but be warned that most
of these cheap power supplies are half wave rectifiers with a capacitor.
This means they are NOT voltage regulated.

*** Er,where did this nonsense come from.Half wave???????????????


Some have a half wave rectifier some have full wave,

** Some adaptors use two diodes, others have four diodes or a bridge
rectifier - in all cases that is full wave rectification.





............... Phil

 

[Ed ()]

WHICH ONE IS HALF WAVE?

If a device has an onboard voltage regulator then the requirement for
the power supply to do the same is false economy and inefficient.

"Lord Garth" <LGarth@Tantalus.net> wrote in message
news:4dx8e.51$yd7.42@newssvr11.news.prodigy.com...
:
: "Brian Goldsmith" <brian.goldsmith@nospam.echo1.com.au> wrote in
message
: news:JDu8e.14670$5F3.13180@news-server.bigpond.net.au...
: >
: > "Lord Garth" <LGarth@Tantalus.net> wrote
: >
: >
: > You can use a power adapter with more current but be warned that
most
: > of these cheap power supplies are half wave rectifiers with a
capacitor.
: > This means they are NOT voltage regulated.
: >
: > *** Er,where did this nonsense come from.Half wave???????????????
: >
: > Brian Goldsmith.
: >
: Some have a half wave rectifier some have full wave, almost all are
crap
: and none of that type are voltage regulated. Cut some open and look
or
: just scope the output. The point is that he should not use that type.
:
:
:
:
:
:
:

 

[Lord Garth]

"Ed ()" <info@standford.com.au> wrote in message
news:42630392$0$18700$afc38c87@news.optusnet.com.au...

WHICH ONE IS HALF WAVE?

If a device has an onboard voltage regulator then the requirement for
the power supply to do the same is false economy and inefficient.

I'd look at the output on a scope. If there were no capacitor the wave form
would have an area of essentially 0 volts between pulses whose frequency
is equal to your mains frequency. The near zero area is 1 half cycle wide.
This uses one rectifier.

If full wave, the pulses are at twice your mains frequency. This uses two
rectifiers.

There is also the full wave bridge configuration. This is used when a
center tap exists. This uses 4 rectifiers.

A regulated DC power supply will simply offset the sweep if the scope
is DC coupled. There should be no sign of the mains AC in the trace,

 

[Ken Taylor]

"Annie" <afritz@aol.com> wrote in message
news:d3so54$hfl$1@reader01.singnet.com.sg...

Hi, I just bought a portable handheld tv, the Casio TV-970, and want to
purchase a universal adaptor for it.
The universal adaptors I've seen have different ratings, from 350mA, to
over 1000mA.
The specifications on the user guide says that it runs on 6 volts, and the
power consumption is approiximately 3.1W.

How much mA do I need?

Regards,
Patrick

Patrick, get one with *at least* 500mA rating. I'd go for about 750mA to
give some margin, esp. since it appears you're in a warmer climate.

Ken

 

[Phil Allison]

"Lord Garth"

"Ed ()"

WHICH ONE IS HALF WAVE?

If a device has an onboard voltage regulator then the requirement for
the power supply to do the same is false economy and inefficient.


I'd look at the output on a scope. If there were no capacitor the wave
form
would have an area of essentially 0 volts between pulses whose frequency
is equal to your mains frequency. The near zero area is 1 half cycle
wide.
This uses one rectifier.

** No regular adaptor on sale is like this.

If full wave, the pulses are at twice your mains frequency. This uses
two
rectifiers.

There is also the full wave bridge configuration. This is used when a
centre tap exists. This uses 4 rectifiers.

** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.

A regulated DC power supply will simply offset the sweep if the scope
is DC coupled.

** Any supply with a filter cap will ALSO show pure DC with no load.

There should be no sign of the mains AC in the trace,

.............. Phil

 

[Lord Garth]

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3cgj8rF6nlrq8U1@individual.net...

"Lord Garth"

"Ed ()"

WHICH ONE IS HALF WAVE?

If a device has an onboard voltage regulator then the requirement for
the power supply to do the same is false economy and inefficient.


I'd look at the output on a scope. If there were no capacitor the wave
form
would have an area of essentially 0 volts between pulses whose frequency
is equal to your mains frequency. The near zero area is 1 half cycle
wide.
This uses one rectifier.


** No regular adaptor on sale is like this.

How odd, I have one. I bought it because the case screwed together allowing
me to remove the diode and cap as these were inside the 70's vintage Corvus
digital clock already. I needed low voltage AC. Its been running since
1979
with only 2 down intervals so far due to failed caps. Clearly, it was one
of
a large quantity of injection molded power supplies so 'regular' is the
qualifier. Maybe it's not regular or common but it is sold.

If full wave, the pulses are at twice your mains frequency. This uses
two
rectifiers.

There is also the full wave bridge configuration. This is used when a
centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.

The full wave bridge would have a center tap if it was part of a bipolar
supply....I'll mark that one half off.

 

[Phil Allison]

"Lord Garth" = congenital idiot
"Phil Allison"

I'd look at the output on a scope. If there were no capacitor the wave
form would have an area of essentially 0 volts between pulses whose
frequency is equal to your mains frequency. The near zero area is 1
half cycle wide. This uses one rectifier.


** No regular adaptor on sale is like this.

How odd, I have one.

** Blatant lie.

I bought it because the case screwed together allowing
me to remove the diode and cap .....

** No cap at all in the one you described above - wanker.

If full wave, the pulses are at twice your mains frequency. This uses
two rectifiers.

There is also the full wave bridge configuration. This is used when a
centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.


The full wave bridge would have a center tap if it was part of a bipolar
supply....I'll mark that one half off.

** What a desperate bloody liar.






............ Phil

 

[Lord Garth]

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3cgmicF6ld82rU1@individual.net...

"Lord Garth" = congenital idiot
"Phil Allison"

I'd look at the output on a scope. If there were no capacitor the
wave
form would have an area of essentially 0 volts between pulses whose
frequency is equal to your mains frequency. The near zero area is 1
half cycle wide. This uses one rectifier.


** No regular adaptor on sale is like this.

How odd, I have one.


** Blatant lie.

I didn't see you standing there in my home 26 years ago!
You're an absolute superman.

I bought it because the case screwed together allowing
me to remove the diode and cap .....


** No cap at all in the one you described above - wanker.

As if you saw me remove said cap...you know, cylindrical device
about 3/4" in length, radial leads and labeled 100uF 16V. Sorry,
wanker was not the manufacturer.

If full wave, the pulses are at twice your mains frequency. This
uses
two rectifiers.

There is also the full wave bridge configuration. This is used when
a
centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.


The full wave bridge would have a center tap if it was part of a bipolar
supply....I'll mark that one half off.



** What a desperate bloody liar.

How would you build a bipolar power supply that used a full wave bridge
and a transformer?

I'm always willing to learn. You can post your schematic to A.B.S.E.

 

[Alan Rutlidge]

"Lord Garth" <LGarth@Tantalus.net> wrote in message
news:URF8e.192$yd7.96@newssvr11.news.prodigy.com...

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3cgmicF6ld82rU1@individual.net...

"Lord Garth" = congenital idiot
"Phil Allison"

I'd look at the output on a scope. If there were no capacitor the
wave
form would have an area of essentially 0 volts between pulses whose
frequency is equal to your mains frequency. The near zero area is
1
half cycle wide. This uses one rectifier.


** No regular adaptor on sale is like this.

How odd, I have one.


** Blatant lie.


I didn't see you standing there in my home 26 years ago!
You're an absolute superman.


I bought it because the case screwed together allowing
me to remove the diode and cap .....


** No cap at all in the one you described above - wanker.

As if you saw me remove said cap...you know, cylindrical device
about 3/4" in length, radial leads and labeled 100uF 16V. Sorry,
wanker was not the manufacturer.



If full wave, the pulses are at twice your mains frequency. This
uses
two rectifiers.

There is also the full wave bridge configuration. This is used
when
a
centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.


The full wave bridge would have a center tap if it was part of a
bipolar
supply....I'll mark that one half off.



** What a desperate bloody liar.

How would you build a bipolar power supply that used a full wave bridge
and a transformer?

I'm always willing to learn. You can post your schematic to A.B.S.E.

Easy, transformer with centre tapped secondary. Common rail connected to
the centre tap.
Bridge rectifier connected to ends of windings. Filtering caps connected
between + and - outputs
of the bridge to the common rail. Easy as...

Check ou the circuit at -
http://emsyl.ece.ua.edu/dawson/App/bipolar%20pwr%20supply%20tech.pdf
The left hand side of the circuit up to capacitors C1 and C2 (before the
regulator ICs)
is an example of a simple bi-polar power supply. The common rail is the
junction between
the two filter capacitors C1 and C2 which connects back to the centre tap
(6) of the
transformer.


Cheers,
Alan

 

[Lord Garth]

"Alan Rutlidge iinet.net.au>" <rutlidge@<NO_SPAM> wrote in message
news:42633580$0$375$5a62ac22@per-qv1-newsreader-01.iinet.net.au...

"Lord Garth" <LGarth@Tantalus.net> wrote in message
news:URF8e.192$yd7.96@newssvr11.news.prodigy.com...

<snip>

There is also the full wave bridge configuration. This is used
when a
centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.


The full wave bridge would have a center tap if it was part of a
bipolar
supply....I'll mark that one half off.



** What a desperate bloody liar.

How would you build a bipolar power supply that used a full wave bridge
and a transformer?

I'm always willing to learn. You can post your schematic to A.B.S.E.

Easy, transformer with centre tapped secondary. Common rail connected to
the centre tap.
Bridge rectifier connected to ends of windings. Filtering caps connected
between + and - outputs
of the bridge to the common rail. Easy as...

Check ou the circuit at -
http://emsyl.ece.ua.edu/dawson/App/bipolar%20pwr%20supply%20tech.pdf
The left hand side of the circuit up to capacitors C1 and C2 (before the
regulator ICs)
is an example of a simple bi-polar power supply. The common rail is the
junction between
the two filter capacitors C1 and C2 which connects back to the centre tap
(6) of the
transformer.


Cheers,
Alan

Exactly! But other seems to think that me a "...desperate bloody liar"
However, I know he knows better. I really could not possibly care less. As
it
is close to tomorrow here, G'day and goodnight from this side of the
terminator.

 

[Phil Allison]

"Lord Garth" = a truly desperate LIAR

"Phil Allison"

I'd look at the output on a scope. If there were no capacitor the
wave form would have an area of essentially 0 volts between pulses whose
frequency is equal to your mains frequency. The near zero area is
1
half cycle wide. This uses one rectifier.


** No regular adaptor on sale is like this.

How odd, I have one.


** Blatant lie.

I didn't see you standing there in my home 26 years ago!
You're an absolute superman.

** By your own words, posted here, it is a falsehood.

I bought it because the case screwed together allowing
me to remove the diode and cap .....


** No cap at all in the one you described above - wanker.

As if you saw me remove said cap...you know, cylindrical device
about 3/4" in length, radial leads and labeled 100uF 16V. Sorry,
wanker was not the manufacturer.

** Hey arsehole - the one you described at the top of this post had NO
CAPACITOR!!!!!!

If full wave, the pulses are at twice your mains frequency. This
uses two rectifiers.

There is also the full wave bridge configuration. This is used when
a centre tap exists. This uses 4 rectifiers.


** More stupid errors !!

The FULL WAVE circuit use two diodes and a centre tap.

A"bridge rectifier" uses four diodes and no need for a centre tap.


The full wave bridge would have a center tap if it was part of a
bipolar
supply....I'll mark that one half off.



** What a desperate bloody liar.

How would you build a bipolar power supply .......

** Go learn to read - fuckhead.





............ Phil

 

[Lord Garth]

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3ch2epF6o5s9oU1@individual.net...

"Lord Garth"

"Phil Allison"

I'd look at the output on a scope. If there were no capacitor the
wave form would have an area of essentially 0 volts between pulses whose
frequency is equal to your mains frequency. The near zero area
is
1
half cycle wide. This uses one rectifier.


snip


** Go learn to read - fuckhead.

Appears you've missed the word IF above.... *yawn*
Good day.