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Chip with simple program for Toy

C

Cursitor Doom

Guest
On Fri, 31 May 2019 05:57:04 -0700, terrypingm wrote:

Thanks. Arduino apparently uses C++, although the book I’m using,
‘Programming Arduino: (Second Edition)‘ by Simon Monks, mainly covers C.
I gather that is adequate for relatively simple sketches.

Are you an Arduino user?
Yes, and indeed additionally a convert from the Pi, which has far too
much video capability I don't need and don't wish to pay 3 times the
price for.

I keep 3 or 4 Arduinos around in case I need one for a bespoke, embedded
application which happens from time to time. They will repay the time
invested in learning how they tick many, many, many times over. IMHO,
they're a fantastic little board for the price.





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protocols constitutes acceptance of this condition.
 
S

S Deyoreo

Guest
On Friday, May 31, 2019 at 6:48:11 AM UTC-4, Terry Pinnell wrote:
I bought my first Arduino UNO R3 kit two weeks ago (the Elegoo Super Starter kit)
and am stepping through its tutorials. In parallel I'm trying to learn the basics of
its C++ based programming language, but that's proving a struggle. I'm impatient to
use Arduino on my own projects so I will take a 'copy/paste/edit' approach. It then
becomes a matter of finding sketches that cover a particular subject and then
tailoring.

I'd therefore appreciate recommendations on Arduino sketch sources that others have
found useful please.

Terry, East Grinstead, UK
I have a crap load. Anything in particular you want to see?
 
B

Bob Engelhardt

Guest
On 7/30/2019 10:04 AM, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over a
two diode full-wave rectifier.  There must be some, else why accept the
extra cost?
You don't need a center tapped transformer with 4 diodes, you do need it
with 2.
 

Guest
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?
 
P

Peter Percival

Guest
jurb6006@gmail.com wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?
What I need is a bridge (the transformer I'm considering doesn't has a
centre tapped secondary) that will handle 420 volts, 3.5 amps. Also,
I'd like recommendations for capacitor and inductor values for smoothing.

--
"He who will not reason is a bigot;
he who cannot is a fool;
he who dares not is a slave."
- Sir William Drummond
 
P

Phil Hobbs

Guest
On 7/30/19 4:29 PM, default wrote:
On Tue, 30 Jul 2019 16:06:06 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 7/30/19 10:42 AM, Bob Engelhardt wrote:
On 7/30/2019 10:04 AM, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over
a two diode full-wave rectifier.  There must be some, else why accept
the extra cost?


You don't need a center tapped transformer with 4 diodes, you do need it
with 2.

Also you get better transformer utilization because the whole winding
conducts on both half-cycles. That improves the RMS-to-average ratio
and reduces transformer heating (other things being equal).

Cheers

Phil Hobbs

I've wondered about that. Seems to me you have two windings
conducting half the time with a CT so the average current and wire
size is smaller (or could be) and you only have two diode-drops
instead of four. So I'd expect the two diode version to be more
efficient (in low voltage power supplies at least, because the diode
drop represents a larger amount of the total V output).
Efficiency is a slightly different issue. Neglecting diode drops, a
half-wave supply has much worse copper losses because (a) you have to
use smaller wire to get twice the secondary voltage, and (b) you're
drawing twice the current for half the time. Item (b) costs you because
the copper loss goes as I**2, so twice the current for half the time
doubles the losses.

At very low voltages the diodes become more important, but it's the
transformer that costs the money. You can make a DC-DC converter for a
dollar or so if that's an issue--a buck converter in both senses. ;)

Cheers

Phil Hobbs

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
 
D

default

Guest
On Tue, 30 Jul 2019 21:26:25 +0100, Peter Percival
<peterxpercival@hotmail.com> wrote:

jurb6006@gmail.com wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

Two diodes sharing a cathode connection. Suppose one wants an
electrically identical pair of diodes but sharing the anode connection?
They make those too. Or you could use half of a full wave bridge if
heat sinking is a consideration. You're not designing this for mass
production where every penny is going to be counted.
$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.
I thought you were working at ~400 V? The storage time is
insignificant in linear mains supplied transformers - it becomes
significant when you are rectifying square waves or high frequencies
or both.
Just how good of a rectifier do you need ?
Not very for 50-60 cycles. A little extra head-room on the voltage is
nice to accommodate power line surges without shorting the diodes.
 
D

default

Guest
On Tue, 30 Jul 2019 16:06:06 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 7/30/19 10:42 AM, Bob Engelhardt wrote:
On 7/30/2019 10:04 AM, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over
a two diode full-wave rectifier.  There must be some, else why accept
the extra cost?


You don't need a center tapped transformer with 4 diodes, you do need it
with 2.

Also you get better transformer utilization because the whole winding
conducts on both half-cycles. That improves the RMS-to-average ratio
and reduces transformer heating (other things being equal).

Cheers

Phil Hobbs
I've wondered about that. Seems to me you have two windings
conducting half the time with a CT so the average current and wire
size is smaller (or could be) and you only have two diode-drops
instead of four. So I'd expect the two diode version to be more
efficient (in low voltage power supplies at least, because the diode
drop represents a larger amount of the total V output).
 
P

Peter Percival

Guest
jurb6006@gmail.com wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615
Two diodes sharing a cathode connection. Suppose one wants an
electrically identical pair of diodes but sharing the anode connection?

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?
 
P

Phil Hobbs

Guest
On 7/30/19 10:42 AM, Bob Engelhardt wrote:
On 7/30/2019 10:04 AM, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over
a two diode full-wave rectifier.  There must be some, else why accept
the extra cost?


You don't need a center tapped transformer with 4 diodes, you do need it
with 2.
Also you get better transformer utilization because the whole winding
conducts on both half-cycles. That improves the RMS-to-average ratio
and reduces transformer heating (other things being equal).

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
 
P

Peter Percival

Guest
Phil Hobbs wrote:
On 7/30/19 10:42 AM, Bob Engelhardt wrote:
On 7/30/2019 10:04 AM, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over
a two diode full-wave rectifier.  There must be some, else why accept
the extra cost?


You don't need a center tapped transformer with 4 diodes, you do need
it with 2.

Also you get better transformer utilization because the whole winding
conducts on both half-cycles.  That improves the RMS-to-average ratio
and reduces transformer heating (other things being equal).

Cheers

Phil Hobbs

Thank you. That's the sort of think I was after.
 
D

default

Guest
On Tue, 30 Jul 2019 20:17:12 +0100, Peter Percival
<peterxpercival@hotmail.com> wrote:

jurb6006@gmail.com wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?


What I need is a bridge (the transformer I'm considering doesn't has a
centre tapped secondary) that will handle 420 volts, 3.5 amps. Also,
I'd like recommendations for capacitor and inductor values for smoothing.
check out:
http://www.valvewizard.co.uk/smoothing.html

Very few amps use Pi filters these days (capacitor inductor capacitor)
that's more common back when capacitors were these huge metal cans
with aluminum foil paper and oil and had a rating of only ~1-10
microfarads. Today they use electrolytic caps with much higher
capacity and avoid the expense of big heavy inductors.

http://education.lenardaudio.com/en/14_valve_amps_6.html
 
P

Phil Allison

Guest
Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over a
two diode full-wave rectifier. There must be some, else why accept the
extra cost?
** The extra cost accrues with the two diode rectifier - cos the larger, centre tapped transformer needed increases cost more than two more diodes do.

Two diode, full wave voltage doubler supplies are also common with direct off mains and transformer isolated supplies.

Two vacuum diode, full wave systems were once the norm but soon became obsolete when silicon diodes appeared in the 1960s.



..... Phil
 
L

Look165

Guest
With a bridge, only 2 diodes on 4 work.
So it preserve diode life.

Peter Percival a Êcrit le 30/07/2019 à 16:04 :
What is the advantage of a four diode bridge full-wave rectifier over
a two diode full-wave rectifier.  There must be some, else why accept
the extra cost?
 
P

Phil Allison

Guest
Look165 is a Fucking Nut Case wrote:


> With a bridge, only 2 diodes on 4 work

** No, they all work.


So it preserve diode life.
** False conclusion derived from a false assertion.

What do people here reckon this nutter is?

A Lebanese school boy?

A Chinese compewter geek ?

Escapee from an Indian mental asylum ?




...... Phil
 
W

whit3rd

Guest
On Tuesday, July 30, 2019 at 7:04:32 AM UTC-7, Peter Percival wrote:
What is the advantage of a four diode bridge full-wave rectifier over a
two diode full-wave rectifier. There must be some, else why accept the
extra cost?
There's copper losses, and diode-drop losses, and core size difference.
For a center-tapped winding, you need longer wire for the coil, and
that raises the core size (unless you accept higher resistive heating
from thinner wire). With a full-wave bridge, four diodes, you have TWO
diode drops on each conducting half-cycle, but with a center-tapped two
diode fullwave rectified circuit, there's only ONE diode drop.

And, given a choice, a four-diode bridge and center-tapped coil gives you
TWO power supplies. That's very convenient.
 

Guest
On Tuesday, July 30, 2019 at 3:26:29 PM UTC-5, Peter Percival wrote:
jurb wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

Two diodes sharing a cathode connection. Suppose one wants an
electrically identical pair of diodes but sharing the anode connection?

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?
They got them, it is just a matter of learning how to use their selector pages. Problem is they changed them and while it all still works it seems you can't get back to "More Filters" and have to back out and reapproach.

They also have diodes in series in those packages.

You want to know about filtering ? Well you got 420 volts at 3.5 amps, that means pretty much a resistance of 120 ohms. Here comes the math, now if you are going brute force there is no inductor, just a ton of capacitance. Figure out how much ripple you can handle and get a cap big enough to not discharge more than that in 1/60th of a second.

That amount of ripple going into a choke will result in a certain voltage loss, which will be half the amplitude of the ripple. If you got 450 and 20 of ripple you got 440. that is what you'll get out of a choke. Into the next cap the whole thing is different because you have an impedance feeding that cap. The selection of the value of that next cap depends on the load and the variations in the load.

Too much inductance you lose all semblance of regulation, less inductance you need bigger caps.

If you have to much trouble figuring this out just adapt an extant design.
 

Guest
With a bridge, only 2 diodes on 4 work

** No, they all work.
You got him on semantics, he probably meant "conduct". Sure they are working when they are conducting, but they are also working when not conducting. They are blocking. When they no longer block they are considered not working.

So it preserve diode life.


** False conclusion derived from a false assertion.
Also ignores some logic on the subject. I won't be as mean as you but I will say it - ijiot ! YOU pick the diodes, they don't pick you ! And do you care if the diode is 50 cents or 60 cents ?

I'm surprised I am even here. I did need a bit of a break though. Got any idea why the hell this Carver Receiver (MX-130) turns off the tuner when I turn off the speakers ? I decided to get away from it, and now I think I have a clue, it switches by relay, maybe somehow the 12 volt line is getting shorted... I'm just here to take a break from it.

But thing is, I gotta write a book or something. These component values and all that, people give way too much attention to that.
 
P

Peter Percival

Guest
jurb6006@gmail.com wrote:
On Tuesday, July 30, 2019 at 3:26:29 PM UTC-5, Peter Percival wrote:
jurb wrote:
You can also use full wave WITH a center tap to get equal plus and minus voltages. Extra rectifiers mean shit -

https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/SFF1604G-C0G/SFF1604GC0G-ND/7358615

Two diodes sharing a cathode connection. Suppose one wants an
electrically identical pair of diodes but sharing the anode connection?

$1.12 and that's two of them. See the specs ? Like 200V., 16A, 35nS.

Just how good of a rectifier do you need ?


They got them, it is just a matter of learning how to use their selector pages. Problem is they changed them and while it all still works it seems you can't get back to "More Filters" and have to back out and reapproach.

They also have diodes in series in those packages.

You want to know about filtering ? Well you got 420 volts at 3.5 amps, that means pretty much a resistance of 120 ohms. Here comes the math, now if you are going brute force there is no inductor, just a ton of capacitance. Figure out how much ripple you can handle and get a cap big enough to not discharge more than that in 1/60th of a second.

That amount of ripple going into a choke will result in a certain voltage loss, which will be half the amplitude of the ripple. If you got 450 and 20 of ripple you got 440. that is what you'll get out of a choke. Into the next cap the whole thing is different because you have an impedance feeding that cap. The selection of the value of that next cap depends on the load and the variations in the load.

Too much inductance you lose all semblance of regulation, less inductance you need bigger caps.

If you have to much trouble figuring this out just adapt an extant design.
Please direct me to one ad tell me how to adapt it.

>
 
P

Phil Allison

Guest
jurb = jerkoff fool @gmail.com wrote:


With a bridge, only 2 diodes on 4 work

** No, they all work.

You got him on semantics, he probably meant "conduct". Sure they are working when they are conducting, but they are also working when not conducting. They are blocking. When they no longer block they are considered not working.
** All four diodes conduct - half of them during each half cycle.

With two diode, full wave rectifiers its one diode per half cycle.

The claim about extending diode life was bullshit

Just like every single claim YOU post.



...... Phil
 
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