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Possible to use:Hassan wrote:
Hello;
I want to design a switching power supply with:
Vin=24 Vdc and Vo=15V @ 7A
I suggest you start with a 24V -> 12V switcher (available at 10A for
vehicular use) and "adjust" it.
Best regards,
Mike.
Maybe I misunderstood you, are you talking about an IC or a complete power"Mike Page" <mike@SCRUBeclectic-CAPSweb.BLAMEco.SWENuk> wrote in
message
news:WN2dnTVmLuuN7-jcRVnyjg@eclipse.net.uk...
Hassan wrote:
Hello;
I want to design a switching power supply with:
Vin=24 Vdc and Vo=15V @ 7A
I suggest you start with a 24V -> 12V switcher (available at 10A for
vehicular use) and "adjust" it.
Best regards,
Mike.
--
Mike Page BEng(Hons) MIEE www.eclectic-web.co.uk
Quiet! Tony's battling the forces of conservatism, whoever we are.
Hi Mike,
Is that 10A peak or 10A continous? If that's 10A continous, do you have
a
part number?
Best regards,
Brian
Usually below 10khz is ok. Anything with a clock in it, above that"Kevin Aylward" <salesEXTRACT@anasoft.co.uk> wrote in message
news:<FdLad.30997$ay5.30712@fe1.news.blueyonder.co.uk>...
boki wrote:
Dear All,
These days I try to implement some baseband remote control,
I was feeling that is possible to complete control home devices
within baseband communications,
By this I assume you man by "Baseband" as non modulated carrier, low
frequency type stuff.
Why RF? for distance?
You cant get any radio waves with a short antenna at low frequencies.
Secondly, if you could, the authorities wouldn't allow you to.
Why Bluetooh? for handshake?
Because its set at frequencies and uses a method that the authorities
will allow your to use unlicensed. End of story.
I don't know what is your low-frequency definition, and I think it is
very ok to transmit audio in non-RF environment.
Indeed it is. You simply can't get any transmit power into the aether atI don't think RF main reason is for short antenna.
Well, I would have to check up on what the the authorities allow. RF isA method ? Nobody need to apply a 'method' to use Bluetooth frequency.
And happens to be the best one for adults.That version of story is for children.
he showed them how to set up the engines to almost double their range,"Clarence" <no@No.com> wrote in message news:<X9Xcd.32148$QJ3.7300@newssvr21.news.prodigy.com>...
"Clarence" <no@No.com> wrote in message
news:O0Xcd.32146$QJ3.3575@newssvr21.news.prodigy.com...
snip
Cut and paste error. Fixed here!
The P-38 was Airforce, and there were 9,923 made. There are some other
aircraft which used the same dual pod design scheme, but not as graceful as the
P-38 Lightning.
F6F Hellcat was a Navy Carrier based plane, 12,272 were made. Same speed and
climb, about the same power but with a single engine.
Marines flew the F4F-3 Wildcat. Only about 1,500 were produced. While slower,
it was highly maneuverable. One Squadron (Black Sheep 214th) accounted for 94
Japanese planes shot down.
The F4F was anywhere from 34 to 70 mph slower than the P-38, depending
upon model, from specs I have seen. The P-38 had a total hp of 2300,
compared to about 2000 for the F4F. The P-38's ceiling was also much
higher (44K). And the P-38 had a cannon (saw those cannon shells at
Wright-Pat recently - would not want to be in any a/c they hit). The
P-38 also demonstrated a 3,000 mile range - longest of any fighter in
WWII.
IIRC, the big advantage of the P38 was RANGE! After Lindburg visited,
(http://www.rfparts.com/) for the transistor? They may have a module asWatson A.Name - \"Watt Sun, the Dark Remover\" wrote...
Winfield Hill wrote ...
I'm looking for an RF amplifier module that can deliver
2 to 3 watts into 50 ohms, over a 20 to 80MHz (or 120
or 150MHz...) range. Variable gain isn't required, but
would be a plus. My budget price is $100 but higher
is OK. I'll get 5 pieces to start, more if necessary.
Hey, Win! Ten-four, good buddy! Are you going into the
CB biz? (just kidding.)
Nah. This is just the right range for driving EOs
(Electro-Optic Modulators).
Run off 12VDC, or 28VDC?
Any voltage is OK, although driving for 50 ohms wideband
one needs at least 14V peak swing, so a 24 to 28V supply
is usual. If I could get the right RF output transistor
(60V, 10W, not too much capacitance), I'd roll my own!
The guys on alt.radio.pirate deal with these kinds of
things and the dealers who sell them. You might check
there.
OK, I'll ask.
This is for a one-off? Have you tried RF Parts
That looks likea good place, thanks I didn't know about them!Winfield Hill wrote:
Watson A.Name - \"Watt Sun, the Dark Remover\" wrote...
Winfield Hill wrote ...
I'm looking for an RF amplifier module that can deliver
2 to 3 watts into 50 ohms, over a 20 to 80MHz (or 120
or 150MHz...) range. Variable gain isn't required, but
would be a plus. My budget price is $100 but higher
is OK. I'll get 5 pieces to start, more if necessary.
Nah. This is just the right range for driving EOs
(Electro-Optic Modulators).
The guys on alt.radio.pirate deal with these kinds of
things and the dealers who sell them. You might check
there.
OK, I'll ask.
This is for a one-off? Have you tried RF Parts
(http://www.rfparts.com/) for the transistor? They may have
a module as well -- if not they used to carry kits designed
from Motorola app notes which were held in fairly good repute.
depends what you mean by small, but yeah. likewise for a resistor inClarence wrote:
"John Popelish" <jpopelish@rica.net> wrote in message
news:41753A07.B1F4C5DE@rica.net...
KM wrote:
John Popelish wrote:
KM wrote:
I have use a LC3803 Linear regurator to design a flyback regurator. A
tronsformer is wind with single primary and double secondary coil (one
for 3volts and one 7volts) the FB was return from 3 volt output. It is
found that the output of 7 volts when unloaded is floating high to 13v
when only 3volts output are loaded. It is found that the overshoot is
causing the raise. What is the possible solution to this?
Are the 3 and 7 volt outputs both positive?
Do the 3 and 7 volt outputs share a common return?
What are the rated full load currents for each output?
both are positive
No, there are individual return separately
That rules out sharing currents in the 3 volt winding.
the rated full load are 2.2A for 3 Volts and 1.2 A for 7volts respectively.
I think I would try winding part of the 7 volt winding bifilar with
the 3 volt winding and putting the rest on top of that. And you will
probably need to add some minimum load to the 7 volt output so that it
is never completely unloaded.
--
John Popelish
How about a "Snubber" on the unloaded winding to control overshoot? I can not
imagine a supply design without some form of rise-time load for a lightly
loaded output. Ripple control is most important at low currents.
Isn't that what a small resistive load across the filter cap amounts
to?
---"Paul Burke" <paul@scazon.com> wrote in message
news:2tju58F20get0U1@uni-berlin.de...
Bob Dang wrote:
Greets,
After searching until near exhaustion, I cannot find an electronics
vender that sells a general purpose wire wrap prototyping board.
The lost art of wire wrap. You can buy boards in Eurocard or (perhaps
still) double Euro size. They are matrix boards with just a pad for each
hole. Some also have a plane grid between the pads on one or both sides.
You buy the wirewrap sockets, though you have to use some ingenuity for
anything other than SIL and DIP packages. then wrap the connections,
plug the components in, debug and find that every single problem
requires almost complete unwiring of the board despite your strategic
wrap pattern, so that in theory any given change requires a maximum of
three connections changed.
The upside was that if a design worked in wirewrap, it would certainly
work when you got it on a PCB.
Paul Burke
IF it was all Digital and modest clock rates!
Bob,"Tam/WB2TT" <t-tammaru@c0mca$t.net> wrote in message
news:<pPCdnaupvL33x-ncRVn-ig@comcast.com>...
"Bob Dang" <msucka0xff@programmer.net> wrote in message
news:528ec373.0410181542.6c227525@posting.google.com...
Greets,
After searching until near exhaustion, I cannot find an electronics
vender that sells a general purpose wire wrap prototyping board. My
specs call for a Wirewrap Board having female connectors on top to
plug chips and such into with male feedthrough pin posts on the
underside (~13.0 mm) with a grounding plane. It needs to be a board
that one could apply a wire wraping tool against the pole points on
the underside with some wire to create custom design circuits. It is
similar to a bread board, but the main difference being that the wire
connections are made on the underside of the board. Most of my general
searchs have turned up tons of "PCB/PWB layout service" shops, but no
actual part. If you could point me in the general direction...
Thanks,
-Bob
I think Augat used to make these, but not many people wirewrap any more.
Tam
What are people using instead? It's been about four years since I used
one for a design. Also I think I remember the board had tiny caps
without leads attached to reduce the noise.
-Bob
---Hassan wrote:
Hello;
I want to design a switching power supply with:
Vin=24 Vdc and Vo=15V @ 7A
Possible to use:
http://www.mpja.com/productview.asp?product=14335+PS
Heavy duty.
---"Keith Williams" <krw@att.bizzzz> wrote in message
news:MPG.1bdee1c373bbb9b8989754@news.individual.net...
--
Keith
Had nothing of value to contribute!
On Tue, 19 Oct 2004 16:43:42 GMT, "Clarence" <no@No.com> wrote:
Had nothing of value to contribute!
Did you get my schematic?Hassan wrote:
Hello;
I want to design a switching power supply with:
Vin=24 Vdc and Vo=15V @ 7A
Lessee- Do the "Mormans" live in Mormandy?For evangelizing, there is a close race between SDA and Mormans.
That would make them an IC surely ?Hello Folks,
Just wondering: Are there any low cost small transistors that have the
baker clamp (saturation protection) built in?
Don't delude yourself that High-Cost amps necessarily sound better.Personally, I think this type of amplifier is more effectively bought
than built today, but if what he has is what you want, it will
probably work reasonably well and is at least built from common parts.
Don't delude yourself that these are truly a high-end product:
You probably will be. It is usually cheaper these days to get a ready madecompare
them to mass-production amplifiers costing a little more than the
retail price of all the parts and you won't be disappointed.
I was thinking of using the common HAM method of winding a wideband RFWatson A.Name - \"Watt Sun, the Dark Remover\" wrote...
Winfield Hill wrote ...
I'm looking for an RF amplifier module that can deliver
2 to 3 watts into 50 ohms, over a 20 to 80MHz (or 120
or 150MHz...) range. Variable gain isn't required, but
would be a plus. My budget price is $100 but higher
is OK. I'll get 5 pieces to start, more if necessary.
Hey, Win! Ten-four, good buddy! Are you going into the
CB biz? (just kidding.)
Nah. This is just the right range for driving EOs
(Electro-Optic Modulators).
Run off 12VDC, or 28VDC?
Any voltage is OK, although driving for 50 ohms wideband
one needs at least 14V peak swing, so a 24 to 28V supply
is usual. If I could get the right RF output transistor
(60V, 10W, not too much capacitance), I'd roll my own!
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
There was a company, Nova I think, that did very nice pwm sineHi John,
What smooths the chop into a sine? Leakage inductance in the
transformer?
Nowadays they do a fine PWM adjust over each half-cycle. With modern PWM
chips that wouldn't be a big deal and that is why I don't understand the
price difference. The sine is approximated by increasing and decreasing
duty cycle, or in some cases, bursts.
Just imagine you had an LM3478 with plenty of loop bandwidth and instead
of feeding the feedback pin directly you'd run this through an opamp
first where the other input is fed a sine wave from a DAC. With a uC
this is even easier because you can have the sine pattern laid down in
its flash memory, plus it can drive the H-bridge as well. That is where
a uC might be the most cost effective solution. Still, I wasn't aware
the inverter guys already did that.
On Sat, 09 Oct 2004 11:59:21 GMT, "Kevin Aylward"
salesEXTRACT@anasoft.co.uk> wrote:
[snip]
That's exactly what I understood Kevin to be saying...The characteristic impedance of a transmission line is *only* the value
of the lines input impedance when terminated by its characteristic
impedance!
For other loads, the input impedance wil *not* be given only by its
x/Length spec.
This simply isn't so. The impedance of the transmission line does not
change in response to the load on the end of it. What does change is
the impedance of the entire *network* as seen by the source.
--MacPearce Consulting
http://www.pearce.uk.com
I go straight to PCB using PCB Pool. It's efficient both in time andWhat are people using instead? It's been about four years since I used
one for a design. Also I think I remember the board had tiny caps
without leads attached to reduce the noise.