how to learn low level RF design
acan...@gmail.com
knowledge of analog and digital electronics and have worked on a very
wide variety of circuits.
I have always wanted to learn low level RF "black art" circuit design,
but its just too difficult on my own, and believe me I have tried.
Whats the best kind of job or environment to get started in this? A
"furnace" to be forged in?
No Spam
Assuming your talking about the more modern and harder to understand RF
in the microwave range.....
Try ham radio. There are allot of v/uhf books around and getting a tech
lic (in the USA) which will allow you on that band is only 25 SIMPLE
questions. Look for people who are hams that do microwave contesting and
"buddy" around with them. Honestly, they will be honored to help.
If your talking HF radio below 100Mhz, your not looking/working hard
enough :-)
EE123
RF is difficult. You really should have an MSEE to be proficient at
it.
THe big problem is that RF extends well into the GHz range.
Even if you stay in the upper 100's of MHz, it is fairly easy to get
tripped up
That would be police radios for example.
Post a question and I will try to answer it!
Dave
Joerg
Designing an HF receiver that can listen to a teeny signal 20kHz from a
station that makes a fluorescent lamp glow _is_ hard work :-)
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM.
Joel Koltner
news:201a9263-1d43-4aa3...@p2g2000prn.googlegroups.com...
On Dec 9, 4:10 pm, acann...@gmail.com wrote:
"RF is difficult. You really should have an MSEE to be proficient at
it."
I'd not convinced it takes an MSEE -- the choice of school and the courses you
take have a lot more to do with it. For instance, Oregon State University --
which likes to think of itself as an "engineering" school -- only has two
professors in their microwaves department, and both are heavy on simulation
and modeling but not so much more "practical" (or at least common) things like
mixers or amplifiers. (Although there are a couple professors in the
microelectronics department who really like PLLs, if you're into that.) As
such, none of the RF courses offered have you sit down and design and actually
build anything more complex than a filter or simple antenna -- no modulators,
no amplifiers, no phasing networks, nada. On the other hand, Portland State
University -- which isn't well-known as an engineering school -- has
individuals such as Richard Campbell
(http://www.ece.pdx.edu/Faculty/Campbell.php) who's into amateur radio and
very much does believe in sitting down and building real devices in his
classes. But even his offerings pale in comparison to what universities such
as Stanford (and MIT and Berkeley and...) offer here:
https://ccnet.stanford.edu/ee414/
"THe big problem is that RF extends well into the GHz range.
Even if you stay in the upper 100's of MHz, it is fairly easy to get
tripped up"
My experience is that upper VHF and low UHF tend to be the hardest, since
you're in this no man's land above HF (where you can largely ignore
parasitics) but still not into "traditional" microwave terrirtory where you
just bite the bullet and specify everything to be so-many-lambda long.
(Granted, that also means -- at least for me -- I throw up my hands and say,
"no, I can't design your a 10GHz active mixer using discrete transistors" --
whereas an IC designer would say, "sure, no problem!")
---Joel
acan...@gmail.com
wrote:
>
> - Show quoted text -
NICE. :). What was the station?
I am talking about making a transmitter and receiver capable of
sending and receiving voice with 3khz bandwidth 1 mile line of sight,
so I suppose that puts me sub 100MHz, and also sub-par as far as my
effort to teach my self it according to one of you. :)
I figure if I could do that, from scratch, using discrete components,
that I would be able to accomplish all of my RF circuit goals for
life, which are basically farting around for fun.
Yeah you are right, I "tried" to do this on my own about 8 years ago
before I even started working as an EE. I've learned quite a bit since
then and I bet I could learn it on my own now. But I am never going to
underestimate the difficulty of successful, non-accidental success of
RF circuitry design. If you can do it, you are pretty much in the
highest rung of the EE ladder, IMHO.
The tricky part here is that I must be able to design the circuit from
scratch to have certain specific parameters, and not just monkey copy
something out of the ARRL book. Although that is an excellent
reference.
Heres a question for you:
Whats the hardest part about doing what I mentioned above? Opinions?
Joel Koltner
news:6440f6f2-bea2-4da1...@g17g2000prg.googlegroups.com...
"I am talking about making a transmitter and receiver capable of
sending and receiving voice with 3khz bandwidth 1 mile line of sight,
so I suppose that puts me sub 100MHz, and also sub-par as far as my
effort to teach my self it according to one of you. :)"
Ignore those who are discouraging you. While it's true that it's unlikely
you'll understand every last little bit of a transceiver design if a handful
of months, that doesn't mean you shouldn't still build one and gain
appreciable knowledge.
"I figure if I could do that, from scratch, using discrete components,
that I would be able to accomplish all of my RF circuit goals for
life, which are basically farting around for fun."
You might find this book useful:
http://www.amazon.com/Build-Intelligent-Amateur-Radio-Transceiver/dp/0070282641
And I would suggest getting your technician class amateur radio license, since
then you can (legally) transmit over many more frequencies than you can
without one.
"The tricky part here is that I must be able to design the circuit from
scratch to have certain specific parameters, and not just monkey copy
something out of the ARRL book. Although that is an excellent
reference."
The ARRL does have a couple of decent design-oriented books besides just the
big monkey-copy book... "Introduction to Radio Frequency Design" by Wes
Hayward is good, as is "Experimental Methods in RF Design."
---Joel
Joerg
> <acan...@gmail.com> wrote in message
> news:6440f6f2-bea2-4da1...@g17g2000prg.googlegroups.com...
> "I am talking about making a transmitter and receiver capable of
> sending and receiving voice with 3khz bandwidth 1 mile line of sight,
> so I suppose that puts me sub 100MHz, and also sub-par as far as my
> effort to teach my self it according to one of you. :)"
>
I can't see google-domain posts, only if someone responds. Anyhow, 3kHz
over 1 mile isn't rocket science. First thing to find out is what bands
are avaliable in your country/region, then which ones are free and if
none suitable which ones are easy to license. 433MHz comes to mind, I
just don't know if voise is legal there. My wife and I have Motorloa
"family radios" at 462/467MHz, sort of a walkie-talkie. Works easily
over a mile.
> Ignore those who are discouraging you. While it's true that it's unlikely
> you'll understand every last little bit of a transceiver design if a handful
> of months, that doesn't mean you shouldn't still build one and gain
> appreciable knowledge.
>
I'll second that. I built my first kilowatt-size RF tube amp when I was
a teenager, blissfully unaware of Maxwell's equations or the dangers in
such a project. Despite the high voltages I am still among the living
and the thing worked like a charm.
> "I figure if I could do that, from scratch, using discrete components,
> that I would be able to accomplish all of my RF circuit goals for
> life, which are basically farting around for fun."
>
Start with chips and MMIC, then work your way towards BFR92 transistors
and such.
> You might find this book useful:
> http://www.amazon.com/Build-Intelligent-Amateur-Radio-Transceiver/dp/0070282641
>
> And I would suggest getting your technician class amateur radio license, since
> then you can (legally) transmit over many more frequencies than you can
> without one.
>
> "The tricky part here is that I must be able to design the circuit from
> scratch to have certain specific parameters, and not just monkey copy
> something out of the ARRL book. Although that is an excellent
> reference."
>
Why not start with a proven design, disect and understand it, and then
modify to your needs? Application notes are also helpful here.
> The ARRL does have a couple of decent design-oriented books besides just the
> big monkey-copy book... "Introduction to Radio Frequency Design" by Wes
> Hayward is good, as is "Experimental Methods in RF Design."
>
To be honest, a large chunk of the know-how I am using in my daily
design jobs originated from the ARRL Handbook. Come to think of it, the
university didn't add all that much. They did have great pubs there
though ...
acan...@gmail.com
> <acann...@gmail.com> wrote in message
>
> news:6440f6f2-bea2-4da1...@g17g2000prg.googlegroups.com...
> "I am talking about making a transmitter and receiver capable of
> sending and receiving voice with 3khz bandwidth 1 mile line of sight,
> so I suppose that puts me sub 100MHz, and also sub-par as far as my
> effort to teach my self it according to one of you. :)"
>
> Ignore those who are discouraging you. While it's true that it's unlikely
> you'll understand every last little bit of a transceiver design if a handful
> of months, that doesn't mean you shouldn't still build one and gain
> appreciable knowledge.
>
> "I figure if I could do that, from scratch, using discrete components,
> that I would be able to accomplish all of my RF circuit goals for
> life, which are basically farting around for fun."
>
>
> And I would suggest getting your technician class amateur radio license, since
> then you can (legally) transmit over many more frequencies than you can
> without one.
>
> "The tricky part here is that I must be able to design the circuit from
> scratch to have certain specific parameters, and not just monkey copy
> something out of the ARRL book. Although that is an excellent
> reference."
>
> The ARRL does have a couple of decent design-oriented books besides just the
> big monkey-copy book... "Introduction to Radio Frequency Design" by Wes
> Hayward is good, as is "Experimental Methods in RF Design."
>
> ---Joel
Thanks for the excellent reply Joel! Don't worry, I am not affected by
discouragers. If I was, I would probably never post here, since there
is always someone who replies "dont do it that way, dont do it at all,
etc.."
Rich Grise
>
> Heres a question for you:
>
> Whats the hardest part about doing what I mentioned above? Opinions?
Yeah, pretty much. ;-)
Cheers!
Rich
Tim Wescott
If you start with the 40 meter band (7MHz) you'll be able to get around
the world with 20 watts out on a good day on single sideband, and less
than a watt with Morse code.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html
Tim Wescott
> The tricky part here is that I must be able to design the circuit from
> scratch to have certain specific parameters, and not just monkey copy
> something out of the ARRL book. Although that is an excellent
> reference.
Don't sneer at "monkey-copying" stuff out of the Handbook. Circuits
from the Handbook are a good starting point; beginning your RF design
career by pasting together various blocks copied out of the handbook
will let you learn incrementally.
Trying to do everything from the ground up all at once will teach you a
_lot_ about why successful designs all tend to stick to a few themes,
but you may get tired of watching the smoke curl out of your circuits
before you figure out how to make things work.
Joerg
A multi-multi ham contest. Meaning the dudes in the next tent were
blasting along on an antenna about 200ft from the one I was using.
Radio Tirana was another story. They blasted commie propaganda into
Europe from Albania, probably using up all the electricity there while
the population was starving. The usual :-(
>> I am talking about making a transmitter and receiver capable of
>> sending and receiving voice with 3khz bandwidth 1 mile line of sight,
>> so I suppose that puts me sub 100MHz, and also sub-par as far as my
>> effort to teach my self it according to one of you. :)
>>
>> I figure if I could do that, from scratch, using discrete components,
>> that I would be able to accomplish all of my RF circuit goals for
>> life, which are basically farting around for fun.
>>
>> Yeah you are right, I "tried" to do this on my own about 8 years ago
>> before I even started working as an EE. I've learned quite a bit since
>> then and I bet I could learn it on my own now. But I am never going to
>> underestimate the difficulty of successful, non-accidental success of
>> RF circuitry design. If you can do it, you are pretty much in the
>> highest rung of the EE ladder, IMHO.
>>
But when one reaches 70 or 80 and the bones get shaky one quickly falls
off that rung again. Got a few decades, I guess ;-)
>> The tricky part here is that I must be able to design the circuit from
>> scratch to have certain specific parameters, and not just monkey copy
>> something out of the ARRL book. Although that is an excellent
>> reference.
>>
>> Heres a question for you:
>>
>> Whats the hardest part about doing what I mentioned above? Opinions?
>>
Can't see your whole original post (Can you use some better domain that
google.com?). But I don't see anything hard with a one-mile line of
sight audio com link. Even well above 100MHz.
> "Introduction to Radio Frequency Design" by Hayward.
>
> If you start with the 40 meter band (7MHz) you'll be able to get around
> the world with 20 watts out on a good day on single sideband, and less
> than a watt with Morse code.
>
And then the neighbor comes hollering that his super-cheap TV is falling
over backwards.
Joel Koltner
news:SbF%k.6331$pr...@flpi149.ffdc.sbc.com...
> And then the neighbor comes hollering that his super-cheap TV is falling
> over backwards.
Google has plenty of hits on "stealth antennas." :-) The ARRL even has books
on the topic!
o...@uakron.edu
Experimental Methods in RF Design
-- by Wes Hayward, W7ZOI, Rick Campbell, KK7B, and Bob Larkin, W7PUA
Serious EE in that book as well as a lot of fun. My boss with 45 years
in EE but no interest in ham radio stole my copy and wont give it
back. For those sceptics out there, its not your normal ARRL/TAB
cookiecutter cookbook. But its not Artech House either.
Older over 100 mhz stuff,
The RSGB microwave handbook. The 60s-70-80s one, not the new
international one.
Not published any more, but still out there new.
Then get on the microwave mailing reflector and listen for a while.
Steve
Phil Allison
<acan...@gmail.com>
** You will not likely get a job doing something you have no ability to do.
Suggest you start off building a "crystal set", these are more interesting
than you might think.
Built my first when I was 7 or 8 years old.
Then a one transistor radio, a one valve set tc.
Get yourself a nice RF generator too - essential really.
A frequency counter and spectrum analyser are also needed for working with
transmitters.
Also, and importantly - do not attempt to re-invent what others did long
ago, instead study what has been made and sold successfully and learn from
it.
..... Phil
Joerg
Yes, but if you have repaired the umpteenth piece of electronics they
all know who dunnit ;-)
Jasen Betts
>
> I am talking about making a transmitter and receiver capable of
> sending and receiving voice with 3khz bandwidth 1 mile line of sight,
> so I suppose that puts me sub 100MHz, and also sub-par as far as my
> effort to teach my self it according to one of you. :)
> Whats the hardest part about doing what I mentioned above? Opinions?
starting, persisting, and finishing.
some suggestions,
1: pick a frequency
2: If both ends are fixed locations, find a good design for directional
antennas.
Jan Panteltje
<notthis...@removethispacbell.net> wrote in
<ABD%k.13576$Ws1....@nlpi064.nbdc.sbc.com>:
>To be honest, a large chunk of the know-how I am using in my daily
>design jobs originated from the ARRL Handbook. Come to think of it, the
>university didn't add all that much. They did have great pubs there
>though ...
hehe.
Yes, maybe that is true.
In my days as a kid, 'RF' was anything above audio... and audio was 20kHz?
Think I started with connecting a headphone to the radio in the living room.
Then a crystal receiver with one of those point contact detectors that you had to
move around a pin on the crystal to find a spot where it worked.
Then a small tube amplifier.
Made it oscillating, my first transmitter.
Then transistors... low power transistor audio amps, super heterodyne, mixers, IF amps.
Then tube audio amps with more power... then TV circuits.
Then high power tube linear, ssb, dsb, deflection circuits, video amps,
anything, build my own scopes, first with tubes then transistors.
Anyways: to learn RF first build a crystal receiver.
Easier these days with good diodes.
At > 1GHz I dunno....
Where I lived at that time, you could detect the TV station with a simple diode
and a LC tuned to about 62 MHz.
If you listened to it you heard the 50 Hz frame frequency.
Such a strong signal, only needed 1 or 2 transistors to drive a CRT..
So, these days, with all digital here, forget about simple receivers like that.
Just buy some PCs, add a wireless access point, good directional antenna, and you
can send anything you want over 1 mile, including video, audio, data, what not,
without needing a license, and without f*cking up the spectrum.
But, the road from crystal receiver to what we have now was fun and interesting for me.
bule...@columbus.rr.com
A good RF Engineer needs to understand the following topics (Each
requiring a fair amount of study and work to understand):
1. Matching concepts. (Why is matching concepts so critical to RF -
must understand - it is a constant theme in RF)
1a. Matching with lumped elemenets
1b. Matching with distibutive elements
1b1. Understanding how distributive (Transmission lines)
elements work
(First step - a quarter wave short is an open :-)
2. Noise, Noise bandwidths,
(as an example, why can you send a signal around the world
in
morse code with 1 watt, and you need a KW for voice?)
3. Amplifier system concepts , Noise figure, IM products, cascading
noise
figures
4. Feedback control theory. Concepts of stability, Loop bandwidth and
loop
response as a function of loop bandwidth.
You need to understand this to do Phase Lock Loops, and ALC
circuits.
5. Filtering concepts and filter designs. Need to understand Zverev
book of filter
tables and how to use it. Need to undersatand concepts of group
delay and
filter trade offs
6. Need to understand , inside and out, how to use a network analyzer
and a spectrum analyzer. Absolutelty must get access to these two
instruments and really , understnd them. (Must play around with
distributive elements on network analyzer)
7. Perhaps most importand is grounding concepts. I would say that in
my experience, 50% of all problems I have ever had ultimately boil
down to a grounding problem. Even to this day, and I know this, I
invariably chase down other issues before I chase grounding, and sure
enough, its a grounding problem.
These are your first steps, the circuit design concepts are not so
hard, but you must be willing to really really bang your head against
the wall to get your circuits to work. You must have tenacity.
Joerg
And always keep a good analog scope. Always. If the OP doesn't yet have
one I'd recommend the Tektronix 2465. Several of my clients followed
that recommendation and got them for around $500 off Ebay. "Wow, it's
like someone turned on the light!" was a common comment. Start every
measurement job with the analog scope first and use a DSO only when the
analog one really, really can't do the job. Like on data lines or very
low frequency erratic noise.
> 7. Perhaps most importand is grounding concepts. I would say that in
> my experience, 50% of all problems I have ever had ultimately boil
> down to a grounding problem. Even to this day, and I know this, I
> invariably chase down other issues before I chase grounding, and sure
> enough, its a grounding problem.
>
Sssssht! Don't take away my business base ... ;-)
>
> These are your first steps, the circuit design concepts are not so
> hard, but you must be willing to really really bang your head against
> the wall to get your circuits to work. You must have tenacity.
>
You forgot one for the guys building analog power circuitry:
8. Always know where the next fire extinguisher is.
RST Engineering (jw)
> Assuming your talking about the more modern and harder to understand RF
> in the microwave range.....
Horsefeathers. Microwave is fairly easy. HF & VHF are fairly easy. From
about 300 MHz. to a gig things get interesting; distributed and transmission
lines are too long, and leaded components have too many unintended
parasitics.
> If your talking HF radio below 100Mhz, your not looking/working hard
> enough :-)
Where the hell did you get that number? HF goes from 3 to 30 MHz, VHF from
30 to 300, UHF from 300 to 3 Gig, and so on.
Hey, learn the difference between "your" and "you're" if you want a
challenge.
Jim
RST Engineering (jw)
>RF is difficult.
RF is easy. COMEDY is difficult.
>You really should have an MSEE to be proficient at
it.
Some of the best I've ever known don't even have a BSEE.
>THe big problem is that RF extends well into the GHz range.
Do tell? I've always thought that RF stopped where light began.
>Even if you stay in the upper 100's of MHz, it is fairly easy to get
tripped up
>That would be police radios for example.
Please don't listen to this clown. He isn't even aware that "police radio"
(or as we who actually work in the field call it, "public service radio")
goes all the way from just barely HF up into the low Gig region. I'd
suggest a good read of 47CFR90 would give you some idea of what you are
talking about.
Go away if you don't know what you are talking about.
Jim
o...@uakron.edu
Good gear for RF is not expensive these days, but perhaps the OP would
like to start cheap:
Some useful toys:
:
The Poor Man's Spectrum Analysis kit:
http://www.science-workshop.com/
Ok, so its a slightly modified TV tuner, but for up to say 850 Mhz,
its a decent vision of whats going on, and you learn about birdies and
mixing and splatter and good RF construction practices. You build it
once and then rebuild it in die cast boxes to clean up the birdies.
You need a decent oscilloscope , say 10 mhz, solid state
deflection , CRT , minimum with it.
Then you read this paper and clean up the IF response and extend the
range
http://www.arrl.org/qex/Henkel.pdf
I know there are better Spec An kits out there, but t 0-110 mhz
doesn't get you much these days.
I will also agree that a decent scope is the best starting point.
A older varacter TV tuner (external pll) with the lid off is a
wonderful place to start, even if your only other gear is a 99$
optoelectronics frequency counter.
I once asked Dr Wenzel to calibrate a diode for me, this paper was the
result:
http://www.techlib.com/files/detect.pdf
Then one of these:
http://www.aade.com/lcmeter.htm
Then one of these:
if you have no budget left after the 1N914 diode, the scope, and the
spec an from the dead VCR, you go here:
http://web.telia.com/~u85920178/
Then some mini-circuits mmics and vcos.
The pro EEs here might laugh at me for this, but starting at this
level with the above stuff in college got me to 10 Ghz SSB phase
locked to a GPS reference.
If you have budget, a PTS160 from ebay is also a great bench tool
Steve Roberts
RST Engineering (jw)
> level with the above stuff in college got me to 10 Ghz SSB phase
> locked to a GPS reference.
Steve ...
The one thing "pros" will *NOT* do is laugh at somebody who has learned the
art and science of making cheap test equipment do the job of high-end
equipment, and who knows the limitations of that method.
I was invited to give a session at RF Expo a few years ago and gave a paper
on how to make a "tracking generator" from LF to a Gig for $20. (A good
zener diode and a few MMIC amplifiers in chain make a dandy broadband noise
source.) The moderator (the chief engineer for a "high end" test equipment
company) had a hissyfit and claimed that I doctored the data. Fortunately I
had the little rascal with me and we simply walked over to a test equipment
vendor and hooked the thing up to their spectrum analyzer. Bingo. Red
faced moderator.
Jim
Mark1
try the ARRL Handbook
and
http://www.amazon.com/RF-Circuit-Design-Christopher-Bowick/dp/0750699469
These are good practical guides to RF
Mark
o...@uakron.edu
<j...@rstengineering.com> wrote:
> > The pro EEs here might laugh at me for this, but starting at this
> > level with the above stuff in college got me to 10 Ghz SSB phase
> > locked to a GPS reference.
>
> Steve ...
>
> The one thing "pros" will *NOT* do is laugh at somebody who has learned the
> art and science of making cheap test equipment do the job of high-end
> equipment, and who knows the limitations of that method.
>
One more good ham radio resource, but written with Attitude:
Green Bay Packet Radio:
Steve
bule...@columbus.rr.com
wrote:
>
> And always keep a good analog scope. Always. If the OP doesn't yet have
> one I'd recommend the Tektronix 2465. Several of my clients followed
> that recommendation and got them for around $500 off Ebay. "Wow, it's
> like someone turned on the light!" was a common comment. Start every
> measurement job with the analog scope first and use a DSO only when the
> analog one really, really can't do the job. Like on data lines or very
> low frequency erratic noise.
>
My experience is a crappy digital scope is better than a great digital
scope when you are looking at analog signals in an RF system.
An analog scope, as you point out, is often better than a digital
scope.
>
> You forgot one for the guys building analog power circuitry:
>
> 8. Always know where the next fire extinguisher is.
And # 8- 2: Now, go get yourself a decent digital scope for power
supply design. Need to catch the one time transcients.
Brent
acan...@gmail.com
are many people like me who want to learn this and now all these
guidelines will be immortalized.
Im getting that Experimental methods in RF design book for sure,and I
will look at the other ones too. I found a library with it and I will
try to get the others too. Hope they dont mind if I keep it all for a
while :)
Tim Williams
this a little while ago, here's the quote:
Wideband stuff is pretty easy: resistors are, for the most part, well
behaved, and with resistance squashing the more unpleasant reactances
in the circuit, you're free to push the boundaries. In wideband
circuits, that means reducing those resistances until the reactances
just start to bite back, then tweaking the circuit (or layout, or...)
until the waveform simply looks good.
But in RF, you're intentionally tempting those parasitics with juicy
LCs, lumped constants that you so wish to be ideal. And they can be
pretty nice, with high Qs for high selectivity. But without that
resistance, parasitics like lead inductance are free to party. You
can try building an amplifier for one frequency, but if it works
better as an oscillator at any other frequency, its amplification is
pretty well doomed.
So I think it's exactly the fault of putting in a tuned circuit (most
likely the capacitor in particular) which creates all those horrible
VHF-UHF+ oscillations that so often spoil RF work. I think it's
valuable to have experience in wideband as well as tuned circuits,
especially where stability and power converge. When you're building a
wideband amp, it has to carry a lot of current, because it's class A
and it's fast. RF power outputs carry a lot of current because
they're outputs, and they're fast because that's the point, but what's
more, they're fast well above and below the one frequency you need
them, so they are both similar to, easier than and harder than a
wideband circuit!
Now, I haven't had much experience with tuned amplifiers, but I think
I've gotten enough of a feel for these things that this might actually
be right.
But I still say RF is black magic. ;-)
Tim
bule...@columbus.rr.com
Additionally,
figure out what each of the following components does by going to
websites of manufacturers of these components and reading their
application notes on them:
Isolator/circulator , PIN diode, Coupler, 3dB hybrid coupler, Power
splitter,
PIN diode/ PIN diode switch, Mixer (read all app notes you can find on
mixers), "off the shelf" filter (Read how to spec them and tradeoffs ,
and figure out different types of filters), SAW device, Voltage
Controlled Oscillator, varactor diode. PI/T attenuators. [ ok, just
thought of simple path: just go to "minicircuits" web site and read
every ap note they have and look at all their components and figure
out what they do]
Also, spend a lot of time thinking about sine waves and cosine waves.
Phase shifts, multiplication of sines/cosines. Figure out what
happens when you add two same exactly same frequency sigs together
(Hint you get same freq, with a phase shift and amplitude
adjustment). Spend time understanding concept of group delay and
phase shift.
Joel Koltner
news:98f0c953-c08c-499c...@t26g2000prh.googlegroups.com...
On Dec 10, 7:03 am, buleg...@columbus.rr.com wrote:
"Isolator/circulator , PIN diode, Coupler, 3dB hybrid coupler, Power
splitter,
PIN diode/ PIN diode switch, Mixer (read all app notes you can find on
mixers), "off the shelf" filter (Read how to spec them and tradeoffs ,
and figure out different types of filters), SAW device, Voltage
Controlled Oscillator, varactor diode. PI/T attenuators."
I'd suggest perusing microwaves101.com as well for a lot of those items...
despite the name of the web site, a lot of the information is targeted towards
VHF and UHF designs as well. A few of the guys hanging out in the forums
there are Real, Live, Microwave Engineers, and their williness to answer
lesser-experienced people's questions is invaluable.
"[ ok, just
thought of simple path: just go to "minicircuits" web site and read
every ap note they have and look at all their components and figure
out what they do]"
Good idea. MiniCircuits actually has surprisingly few app notes given how
many parts they have, and the bulk of them seem to have been written a couple
decades ago, but the technology is still largely the same and the quality is
good.
---Joel
Simon S Aysdie
> ** You will not likely get a job doing something you have no ability to do.
He could be Prezident.
Simon S Aysdie
> Green Bay Packet Radio:
>
> http://www.qsl.net/n9zia/
by r.meck and g.white:
rex
>Im getting that Experimental methods in RF design book for sure,and I
>will look at the other ones too. I found a library with it and I will
>try to get the others too. Hope they dont mind if I keep it all for a
>while :)
The library is good, but if you find it valuable enough to keep around,
Google: "experimental methods in rf design"
There are many places you can buy it to keep in your library. Your own
library is a good thing too.
rex
>I'm excited!! Thanks for all the hints and tips folks! I am sure there
>are many people like me who want to learn this and now all these
>guidelines will be immortalized.
I probably shouldn't mention this since you have lots of good book
references already, but for RF, one book I have is a near-miss great
introduction. The book is "High Frequency Circuit Design" by James Hardy
1979.
I say near miss because it covers a lot of ground and prsents the
subjects in a very clear way -- all good so far -- but the book badly
needed a better editor.
Been a while since I looked at the problems, but I think I remember
examples where the math didn't quite work, a schematic or diagram that
wasn't quite right, stuff that made you scratch your head until you
figured out the book was just a little bit wrong.
So I only mention this book because 90+% of it was very good, but the
mistakes made it frustrating, especially if you were just learning. I
just did a google to see if there was a newer version that might be
better, but no. Seems just the one flawed version.
I still go to it for generally good straightforward coverage of many RF
topics, but I now hold a grain of scepticism if something doesn't seem
quite right and double check with other sources.
T
says...
Another good way is to get your Amateur Extra license. Get the study
guides from the ARRL, they actually present the theory as opposed to
drilling you on the question pool.
JosephKK
<zapwireD...@yahoo.com> wrote:
><acan...@gmail.com> wrote in message
>news:6440f6f2-bea2-4da1...@g17g2000prg.googlegroups.com...
>"I am talking about making a transmitter and receiver capable of
>sending and receiving voice with 3khz bandwidth 1 mile line of sight,
>so I suppose that puts me sub 100MHz, and also sub-par as far as my
>effort to teach my self it according to one of you. :)"
>
>Ignore those who are discouraging you. While it's true that it's unlikely
>you'll understand every last little bit of a transceiver design if a handful
>of months, that doesn't mean you shouldn't still build one and gain
>appreciable knowledge.
>
>"I figure if I could do that, from scratch, using discrete components,
>that I would be able to accomplish all of my RF circuit goals for
>life, which are basically farting around for fun."
>
>You might find this book useful:
>http://www.amazon.com/Build-Intelligent-Amateur-Radio-Transceiver/dp/0070282641
>
>And I would suggest getting your technician class amateur radio license, since
>then you can (legally) transmit over many more frequencies than you can
>without one.
>
>"The tricky part here is that I must be able to design the circuit from
>scratch to have certain specific parameters, and not just monkey copy
>something out of the ARRL book. Although that is an excellent
>reference."
>
>The ARRL does have a couple of decent design-oriented books besides just the
>big monkey-copy book... "Introduction to Radio Frequency Design" by Wes
>Hayward is good, as is "Experimental Methods in RF Design."
>
>---Joel
>
Just the same the FCC has been making major changes to armature radio
licensing, no code any more, just novice, general and extra classes.
Go for it. I will soon.
JosephKK
That is a little bit different viewpoint.
JosephKK
It is not that anything you contributed is actually incorrect. But do
you have to be nasty about it?
JosephKK
wrote:
>On Dec 9, 4:10 pm, acann...@gmail.com wrote:
>> I work as an EE, I don't have a degree, but I do have a working
>> knowledge of analog and digital electronics and have worked on a very
>> wide variety of circuits.
>>
>> I have always wanted to learn low level RF "black art" circuit design,
>> but its just too difficult on my own, and believe me I have tried.
>>
>> Whats the best kind of job or environment to get started in this? A
>> "furnace" to be forged in?
>
>RF is difficult. You really should have an MSEE to be proficient at
>it.
>THe big problem is that RF extends well into the GHz range.
>Even if you stay in the upper 100's of MHz, it is fairly easy to get
>tripped up
>That would be police radios for example.
>
>Post a question and I will try to answer it!
>
>Dave
Arrogant overeducated nutter. "Clap, Clap, Clap, back in the box"
JosephKK
This freaky love of GPS derived references astounds me. There is NO
technical justification for it. MARKETING.
Dave
"Tim Williams" <tmor...@gmail.com> wrote in message
news:54d8a3e2-1e49-49a7...@s9g2000prm.googlegroups.com...
<snip>
But I still say RF is black magic. ;-)
Tim
It's the biasing of JFETs that appears to be a dark art to me. Can get them
to do most of what I want, but not that last little bit... And can't seem
to find any info on this subject other than "It's best to use something like
Electronics Workbench."
Dave
Nico Coesel
>On Dec 9, 2:18=A0pm, Joerg <notthisjoerg...@removethispacbell.net>
>wrote:
>> No Spam wrote:
>> > On Tue, 09 Dec 2008 13:10:17 -0800, acannell wrote:
>>
>> >> I work as an EE, I don't have a degree, but I do have a working
>> >> knowledge of analog and digital electronics and have worked on a very
>> >> wide variety of circuits.
>>
>> >> I have always wanted to learn low level RF "black art" circuit design,
>> >> but its just too difficult on my own, and believe me I have tried.
>>
>> Designing an HF receiver that can listen to a teeny signal 20kHz from a
>> station that makes a fluorescent lamp glow _is_ hard work :-)
>>
>
>I figure if I could do that, from scratch, using discrete components,
>that I would be able to accomplish all of my RF circuit goals for
>life, which are basically farting around for fun.
>
>Yeah you are right, I "tried" to do this on my own about 8 years ago
>before I even started working as an EE. I've learned quite a bit since
>then and I bet I could learn it on my own now. But I am never going to
>underestimate the difficulty of successful, non-accidental success of
>RF circuitry design. If you can do it, you are pretty much in the
>highest rung of the EE ladder, IMHO.
>
>The tricky part here is that I must be able to design the circuit from
>scratch to have certain specific parameters, and not just monkey copy
>something out of the ARRL book. Although that is an excellent
>reference.
Learning is copying. So what you basically need to do is get some test
equipment and start building circuits others have made (copying). The
next step is modifying the circuits according to your own
requirements. This will get you the understanding required to design
circuits yourself. But this won't happen overnight.
--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
"If it doesn't fit, use a bigger hammer!"
--------------------------------------------------------------
Joerg
But it ain't armature radio :-)
Only when supplied by a nucular power station ...
--
SCNR, Joerg
Joerg
> "Tim Williams" <tmor...@gmail.com> wrote in message
> news:54d8a3e2-1e49-49a7...@s9g2000prm.googlegroups.com...
>
>
> <snip>
>
> But I still say RF is black magic. ;-)
>
Nah. After one or two decades things become quite normal :-)
> Tim
>
> It's the biasing of JFETs that appears to be a dark art to me. Can get them
> to do most of what I want, but not that last little bit... And can't seem
> to find any info on this subject other than "It's best to use something like
> Electronics Workbench."
>
They aren't much different than tubes, except that the bias voltages are
almost an order of magnitude lower and production spread in the
pinch-off region is very high. Easily +/-50%. On the bonus side they are
more than two orders of magnitude cheaper than tubes were. And you don't
get zinged so often.
--
Regards, Joerg
Michael A. Terrell
I don't think he's wrapped to tight.
--
http://improve-usenet.org/index.html
aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.
If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm
There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
JosephKK
Naw, it just takes a rotating antenna.
JosephKK
Naw, my spelling brushes are just a little loose.
Michael A. Terrell
Where is an armature lathe when you need to smooth out the rough
spots? ;-)
Michael A. Terrell
Who do you think you are? Radar O'Riley?
JosephKK
If i ever find "A Radar Man with Dipole Feet" again i will send you
copy. Circa 1975 by Jacob van Compernole.
Michael A. Terrell
JosephKK wrote:
>
> If I ever find "A Radar Man with Dipole Feet" again I will send you
> copy. Circa 1975 by Jacob van Compernole.
What's wrong with Merrill I. Skolnik's 'Radar Handbook'?
JosephKK
<mike.t...@earthlink.net> wrote:
>
>JosephKK wrote:
>>
>> If I ever find "A Radar Man with Dipole Feet" again I will send you
>> copy. Circa 1975 by Jacob van Compernole.
>
>
> What's wrong with Merrill I. Skolnik's 'Radar Handbook'?
I would not know. But the target audience, the style and intended
result are different.