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transmistter

D

DG

Jan 1, 1970
0
Hi

im very new,

and i was wondering wondering the possibilty of buliding a PLL transmitter
that covers the range from 10mhz to 999mhz, and also fits in your hand?

are the analog 900mhz cordless phones fm modulated?

is there any type of kit or device that woudl do the same?

DG

D

default

Jan 1, 1970
0
Hi

im very new, How new? born yesterday?
and i was wondering wondering the possibilty of buliding a PLL transmitter
that covers the range from 10mhz to 999mhz, and also fits in your hand?
Not that good and likely to be expensive. You don't say what you hope
to achieve with it, and what the power requirements are, and how it
should be modulated. There maybe something simpler that would achieve
your ends. And hand held to boot? Unlikely.
are the analog 900mhz cordless phones fm modulated? yes
is there any type of kit or device that woudl do the same?
I'm not aware of one. Some info on the web in using cell phones as
jammers for other cell phones (800MHZ) by sweeping through the cell
frequencies. Some of the surplus outlets come up with cell phone
equipment from time to time, but they aren't inexpensive.
Building radio jammers? phone jammers? What is the goal?

It "can" be done, but this isn't a newbie project, and hand held would
be very difficult in an amateur design. Using the transmitter may be
illegal depending on how and it is used and if you are licensed to use
it.

S

Spajky

Jan 1, 1970
0
are the analog 900mhz cordless phones fm modulated?

yes ...

-- Regards, SPAJKY
& visit site - http://www.spajky.vze.com
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J

John Fortier

Jan 1, 1970
0
DG said:
Hi

im very new,

and i was wondering wondering the possibilty of buliding a PLL transmitter
that covers the range from 10mhz to 999mhz, and also fits in your hand?

are the analog 900mhz cordless phones fm modulated?

is there any type of kit or device that woudl do the same?

DG

It would be possible to build a PLL with that frequency range, but the
output gain stages would be another matter entirely. And, unless you want
to spend as much on it's development as, for example, Nokia have spent on
the development of their cell phones, getting it to fit into the palm of
your hand would be exceptionally difficult if not impossible. This is not a
project for someone who is very new.

One word about messing about with cordless phones; illegal.

I'm sorry, do the same what?

I wish I could be a bit more encouraging, but shouldn't you learn the basics
before tackling a project such as the one you seem to be contemplating?

John

T

tim kettring

Jan 1, 1970
0
Extreamly unlikely , and probably illegal .

tim

D

DG

Jan 1, 1970
0
would it be easier to build a reciever that pulls off that range?and is
small?

and no i dont want to jam anything, 10 foot range at most

D

default

Jan 1, 1970
0
would it be easier to build a reciever that pulls off that range?and is
small?

and no i dont want to jam anything, 10 foot range at most

How did you get from wanting to build a wide range transmitter to a
receiver? Assume this would also be wide band or is there a frequency
you are interested in?

That might be easier, depending on how selective you want it. Bug
detectors are wide band receivers that indicate that a transmitter is
nearby. They are sensitive enough but not selective, some have
demodulated outputs so you can listen in.

Some commercial scanners will work over wide ranges, and are pocket
size. (not aware of any 10-900MHZ) Many receivers only allow one or
two types of demodulation and certain frequencies usually carry
different modulation. Above say 40 MHZ there is more FM modulation
(narrow band and wide band), below 32 it is AM, CW, FSK, or SSB.
There are some receivers that will cover from below the broadcast
bands to the gigahertz satellite bands. They ain't cheap or small . .
..

Since you are new and interested in RF, why not check out Ramsey
electronics? www.ramseyelectronics.com/ They have a few frequency
synthesized (PLL) transmitters (illegal- for the average joe) FM radio
stations, receivers, and high tech toys in kit form. At least get the
paper catalog and check it out. This way you can build something
reasonably advanced and learn from it.

The American Radio Relay League should also be a starting point for
radio. They have a pretty good bookstore and promote the hobby of
amateur radio. I recommend the "Secrets of RF Circuit Design" by
Joseph J. Carr, ISBN 0-8306-8710-6, Tab Books a division of McGraw
Hill. I bought mine through the ARRL. It is a good basic book and at
the same time interesting and up to date. Several circuits you can
build, antennas and how they work, etc.. Not too heavy and easy to
understand.

The "Encyclopedia of Electronics Circuits" (new volume every year or
so) is chock full of circuits and interesting. Very little
explanation, but reference where they found the circuit and give a
schematic. The past volumes are very inexpensive on half.com or on
line book stores. New volumes are expensive, but each volume is
unique with all different circuits.

D

DG

Jan 1, 1970
0
woudl you know of a good starting book, that covers everythign from rf,
digital and analog? my math level is calculus, if that helps. i cant seem to
find a good one, art of electronics is way too old and doenst have what i
want

Thanks

D

default

Jan 1, 1970
0
woudl you know of a good starting book, that covers everythign from rf,
digital and analog? my math level is calculus, if that helps. i cant seem to
find a good one, art of electronics is way too old and doenst have what i
want

Thanks
It would help to know what your interest is. There are lots of
"starting books" There are none that will take you from knowing
nothing about electricity to designing electronics.

Are you at a zero knowledge point? What spurred your interest in
electronics? What are the things that seem interesting (what types of
applications?). What do you hope to do with the knowledge?

I ask those things because if you are interested and enthusiastic
about some facet of electronics it would be best for you to pursue
that interest.

There is a difference between knowledge and understanding. Schools
are great for imparting knowledge, but understanding is usually fueled
by curiosity and an intrinsic need to learn. (if you have that need,
it is a shame to waste it)

Let's say,for argument's sake,that you are at the starting gate.
Today, the best way to learn on one's own, in my opinion, is with the
Heathkit electronics courses. The individual courses are set up so
you buy one,do the work, send in the test, get graded and move to the
next.

I was fortunate to take a job that had as a requirement, for me to
take the company's own learning program. They used heathkit and I got
a great set of basic books out of the deal. It was redundant for me
and I breezed through the one year program in two weeks, but the books
are still on my shelf and I still use them. They went from DC
electronics to digital and microprocessors.

http://www.heathkit.com/html/ilp.html

They were quite reasonable in 1980 when I went through them. (~$40) The company gave me DC electronics through digital electronics, I added op amps, microprocessors, opto electronics, and a few others. They picked up the cost by reimbursing me. Heathkit wants you to buy their "trainer" and the course comes with parts to "breadboard" the circuits and see how they work. I didn't actually do all that, just took the tests. If you are dead broke or nearly so, the "Basic Electricity and Electronics," US navy book is on the market, still published by Dover Books. "Advanced Electronics," is also there but a little dated. The basic AC and DC theory is never outdated. Heathkit is drifting off in making computer/network courses now, but their basic "core" learning modules are still there and still available in "individual learning" formats. Electronics is far too advanced to learn it all. You're going to specialize or compromise somewhere - the basics are going to be necessary in everything you do. So start at DC and AC electronics theory, then semiconductor components, then circuits - by then you'll see more possibilities and interests and can chart your course. Another resource might be a mentor. Some old geezer with time on his hands that will help you stay interested and learning. The other choice is a college or community college - but you really have to shop around to find a good one. Lots of people are selling degrees these days. If it were my money, I'd want to make sure I got some real understanding, not just a piece of paper. Sit in on a course, look for bright enthusiastic teachers and students. Stay away from the guy that gets in front of a class and drones, while the drones in the seats take notes. Learning should be fun. Hell, learning is fun - some teachers can suck the fun out of it. Learning is the active roll, teaching is the passive roll. The best teachers guide, they don't dictate or just put in a days "work." D default Jan 1, 1970 0 woudl you know of a good starting book, that covers everythign from rf, digital and analog? my math level is calculus, if that helps. i cant seem to find a good one, art of electronics is way too old and doenst have what i want Thanks The books are listed as paperback. Mine are looseleaf with the binder supplied and the pages shrink wrapped (when they were shipped) This was found on half.com searching under "books" and Heathkit That won't get you the components or heath graded test or certificate, but the knowlege is there, and it is an inexpensive way to find out if you want to do it. THIS ONE THIRD Semiconductor Devices Zenith Educational Systems Heathkit » Paperback, 1983 - Buy it for$3.75 (Save 71%)

THIS ONE FIRST:
Dc Electronics Zenith Education Systems Heathkit
» Paperback, 1983 - Buy it for $4.99 (Save 61%) This is number 5 or 6: Digital Techniques: A Step-By-Step Introduction Zenith Educational Systems Heathkit » Paperback, 1983 - Buy it for$9.00 (Save 39%)

THIS ONE SECOND:
Ac Electronics Zenith Educational Systems Heathkit
» Paperback, 1983 - Buy it for $3.75 (Save 71%) This one was/is extra curricular: Electronic Communications Zenith Educational Systems Heathkit » Paperback, 1983 - Buy it for$6.50 (Save 49%)

J

Joshua K Drumeller

Jan 1, 1970
0
To do this would be illegal. You have to have an FCC license to work on
transmitters and receivers in allot of those frequencies you want to cover.
Not to mention the separate licenses you would need to transmit,
If you are a newbie to electronics and you want to work with transmitters
and receivers it would be best to get the ARRL technicians study book then
take a simple no code tech HAM test then you can play around with that stuff
once you are licensed on the allowable frequencies.

Josh

D

DG

Jan 1, 1970
0
thanks for the infor,

i on specialzing in wireless data tranmsision and interfacing with comptuer,
but this project had nothing to do with that.

thanks a ton