Maker Pro
Maker Pro

2.7ghz spectrum analyzer

P

payam

Jan 1, 1970
0
hi, natinal instruments has rf signal generator PXI-5660 that can work to
2.7ghz , can i make something near it as a electronics enginearing student?
any help would be most appriciated!
yhanks
 
B

Ben Pope

Jan 1, 1970
0
payam said:
hi, natinal instruments has rf signal generator PXI-5660 that can work to
2.7ghz , can i make something near it as a electronics enginearing
student? any help would be most appriciated!
yhanks

How much do you think has changed in the last 2 days?

The answer is was no 2 days ago, it's not today, it will be no tomorrow.

You are extremely unlikely to have the resources available to you, even if
you had the slightest chance of designing such a thing yourself.

Ben
 
S

SioL

Jan 1, 1970
0
Ben Pope said:
How much do you think has changed in the last 2 days?

The answer is was no 2 days ago, it's not today, it will be no tomorrow.

You are extremely unlikely to have the resources available to you, even if
you had the slightest chance of designing such a thing yourself.

Ben

It can be done, depending on exact requirements.

A 2-4GHz wideband VCO was published a few years ago by one of our local geniuses,
Matjaz Vidmar, as part of his excellent homebrew spectrum analyzer.

If you follow his instructions word by word, you've got a nice VCO. And if you
add a PLL and attenuators to that, its close to being a signal generator.

It all depends on what exactly he really needs. And he may be able to get
testing equipment at university to verify operation.

Siol
 
B

Ben Pope

Jan 1, 1970
0
SioL said:
It can be done, depending on exact requirements.

A 2-4GHz wideband VCO was published a few years ago by one of our local
geniuses, Matjaz Vidmar, as part of his excellent homebrew spectrum
analyzer.

If you follow his instructions word by word, you've got a nice VCO. And
if you
add a PLL and attenuators to that, its close to being a signal generator.

It all depends on what exactly he really needs. And he may be able to get
testing equipment at university to verify operation.

Even by somebody who doesn't seem to know whether he's making a spectrum
analyser or a sig gen?

Adding a PLL and other bits and pieces to work at the Gigahertz range is
till not trivial... I'd be very suprised if this guy could make it work.
OK... just to make him happy...

Yes payam, it's possible. I wish you luck. :)

Ben
 
F

Fred Bloggs

Jan 1, 1970
0
Ben said:
How much do you think has changed in the last 2 days?

The answer is was no 2 days ago, it's not today, it will be no tomorrow.

You are extremely unlikely to have the resources available to you, even if
you had the slightest chance of designing such a thing yourself.

Ben

He's posting from Iran- let Bill Sloman help him out-)
 
S

SioL

Jan 1, 1970
0
Ben Pope said:
Even by somebody who doesn't seem to know whether he's making a spectrum
analyser or a sig gen?

Adding a PLL and other bits and pieces to work at the Gigahertz range is
till not trivial... I'd be very suprised if this guy could make it work.
OK... just to make him happy...

Yes payam, it's possible. I wish you luck. :)

Ben

What is payam? Anyway, if you're too incompetent to build one, it doesn't necessarily
mean others can't.

http://www.clearlight.com/~vhfcomm/s53mvvco.htm (Its a rather long intro)

The PCB's and parts are readily available, a HAM with some technical
skills is able to construct this.

Siol
 
B

Ben Pope

Jan 1, 1970
0
SioL said:
What is payam? Anyway, if you're too incompetent to build one, it doesn't
necessarily mean others can't.


More like who... he's the OP. I'm not talking about me and my
competencies... I know what they are.

Try reading the whole thread before commenting - it gives context. And the
other threads asking the same question from the same OP merely two days ago.

Ben
 
S

SioL

Jan 1, 1970
0
Ben Pope said:
I thought Bill was from Netherlands...

Ben

You guys should really be ashamed of yourself. Even if I was from Iran,
what's that got to do with anything. I was merely expressing my opinion.

Go play with the other Ku klux klan members.

Siol
 
R

Robert Lacoste

Jan 1, 1970
0
I think the title is wrong : the first post was regarding an RF spectrum
analyzer, this one seems about an RF generator (but the title is
unchanged...). My opinion is that building an RF generator going up to a
couple of GHz is easy (just buy a VCO module and apply a voltage on the
input, you will get something like an RF signal at the output ...), however
building a reasonnably good RF generator is not easy at all ! So everything
depends on the specifications... If a phase noise as high as the carrier
some tens of MHz away is fine, and if a phase lock is not needed, then it is
quite easy...

Robert Lacoste
http://www.alciom.com
 
B

Ben Pope

Jan 1, 1970
0
You guys should really be ashamed of yourself. Even if I was from Iran,
what's that got to do with anything. I was merely expressing my opinion.

Fred was talking about payam, not you.
Go play with the other Ku klux klan members.

You really should learn to comprehend what you read. I have no form of
xenophobia, nor did I say anything of that sort.

Ben
 
B

Ben Pope

Jan 1, 1970
0
Robert said:
I think the title is wrong : the first post was regarding an RF spectrum
analyzer, this one seems about an RF generator (but the title is
unchanged...).

Both titles are for signal/spectrum analayzer, yet refer to the NI PXI-5660
Sig Gen (if indeed, thats what it is)
My opinion is that building an RF generator going up to a
couple of GHz is easy (just buy a VCO module and apply a voltage on the
input, you will get something like an RF signal at the output ...),
however building a reasonnably good RF generator is not easy at all !

Indeed. We can all make a noise, but as to whether it's useful or not is
something else.

I can sit here (well... in the kitchen) and press the gas hob sparky thing
to make broadband noise possibly including GHz frequencies but I'd be hard
pushed to do anything with them. Other than light the hob or give myself a
shock, obviously

I'm assuming his posts are regarding signal generation, propogation and
presumably reception at x-ray and gamma frequencies (re his other posts over
the last week or so).

Ben
 
S

SioL

Jan 1, 1970
0
Ben Pope said:
Fred was talking about payam, not you.


You really should learn to comprehend what you read. I have no form of
xenophobia, nor did I say anything of that sort.

That was indeed ment for Fred, I know him well from his previous xenofobic
rants, which is why he is in my Ctrl-K. I'm sorry if a few schrapnels got you as well :)

Yes, I agree, it all depends on what this guy really needs. It may be viable if his
requirements are not high.

Siol
 
B

Ben Pope

Jan 1, 1970
0
SioL said:
That was indeed ment for Fred, I know him well from his previous xenofobic
rants, which is why he is in my Ctrl-K. I'm sorry if a few schrapnels
got you as well :)

It happens...
Yes, I agree, it all depends on what this guy really needs. It may be
viable if his requirements are not high.


As far as I can gather, he's a student, and it's his choice of project. I
guess he'll learn KISS the hard way if he insists on this line of
development.

payam: KISS means Keep It Simple, Stupid. It's a well known engineering
principle. You'll get a better mark for doing something well than
attempting and failing.something hard. Bring yourself down a good few
orders of magnitude in frequency and you'll be fine.

Ben
 
S

SioL

Jan 1, 1970
0
Ben Pope said:
It happens...



As far as I can gather, he's a student, and it's his choice of project. I
guess he'll learn KISS the hard way if he insists on this line of
development.

payam: KISS means Keep It Simple, Stupid. It's a well known engineering
principle. You'll get a better mark for doing something well than
attempting and failing.something hard. Bring yourself down a good few
orders of magnitude in frequency and you'll be fine.

Ben

Yeah, how about MAX038 for a start?

Siol
 
B

Ben Pope

Jan 1, 1970
0
SioL said:
Yeah, how about MAX038 for a start?

Hehe, 3 orders of magnitude... perfect. Kind of cuts his project down to
the bare essentials... Single chip COTS solution. :)

A* for development cost.

:p

Ben
 
F

Fred Bloggs

Jan 1, 1970
0
SioL said:
That was indeed ment for Fred, I know him well from his previous xenofobic
rants, which is why he is in my Ctrl-K. I'm sorry if a few schrapnels got you as well :)

The word is xenophobic, you good for nothing eastern european trash, and
you're wrong about that- please visit the US so we can make you a
permanent part of the landscape.
 
F

Frank Raffaeli

Jan 1, 1970
0
Ben Pope said:
It happens...



As far as I can gather, he's a student, and it's his choice of project. I
guess he'll learn KISS the hard way if he insists on this line of
development.

payam: KISS means Keep It Simple, Stupid. It's a well known engineering
principle. You'll get a better mark for doing something well than
attempting and failing.something hard. Bring yourself down a good few
orders of magnitude in frequency and you'll be fine.

I'm going to disagree here ... as a former electrical engineering
instructor at the University of Michigan ... we rewarded *some*
attempts at very difficult projects, as long as there was a partial
success, and the students had done the work themselves. I recall one
group of students in my class in 1986 ... they built a rather nice TV
receiver - Lo VHF only. There wasn't enough time to finish the
display, so they wired it to the X,Y and Z inputs of the laboratory
scope. I saw a crude picture, and gave them an "A".

The KISS principle belongs to engineering ... not always taught at the
academic level, even though I agree it should be. In the real world,
there ARE designers needed for spectrum analysers and RF generators.
There's nothing wrong with getting started early.

SIOL - thank you for posting the link from Matjaz Vidmar. That is a
very nice summary of VCO design.

payam - Another source I have found helpful:
"Microwave Circuit Design Using Linear and Nonlinear Techniques"
by Vendelin, Rohde. (and third author I forget, since I lent it out)

Frank Raffaeli
http://www.aomwireless.com/
 
B

Ben Pope

Jan 1, 1970
0
Frank said:
I'm going to disagree here ... as a former electrical engineering
instructor at the University of Michigan ... we rewarded *some*
attempts at very difficult projects, as long as there was a partial
success, and the students had done the work themselves. I recall one
group of students in my class in 1986 ... they built a rather nice TV
receiver - Lo VHF only. There wasn't enough time to finish the
display, so they wired it to the X,Y and Z inputs of the laboratory
scope. I saw a crude picture, and gave them an "A".

Well thats fine. But if somebody attempts something that is clearly outside
of their reach, expecting to have it all finished and working then they're
doing something wrong. Obviously getting somewhere with a difficult project
is great, but as I'm sure you're aware you really should have some idea of
whats possible within your constraints before starting it. All engineering
projects start with a feasability study...
The KISS principle belongs to engineering ... not always taught at the
academic level, even though I agree it should be. In the real world,
there ARE designers needed for spectrum analysers and RF generators.
There's nothing wrong with getting started early.

True, but the MHz range would be a better place to start playing with HF
design than GHz, surely.

I wish the guy luck - I've learnt the hard way that biting off more than you
can chew usually ends in disappointment - I suspect that I'm not the only
person here. I'm guessing that this is one of the first practical projects
of this size that the guy has undertaken and also the first thing he's tried
in HF design. He WILL underestimate the amount of time it'll take him.
Probably by a factor of 3 or more.

Ben
 
F

Frank Raffaeli

Jan 1, 1970
0
Ben Pope said:
Well thats fine. But if somebody attempts something that is clearly outside
of their reach, expecting to have it all finished and working then they're
doing something wrong. Obviously getting somewhere with a difficult project
is great, but as I'm sure you're aware you really should have some idea of
whats possible within your constraints before starting it. All engineering
projects start with a feasability study...

Hmm ... I don't think I feel qualified to determine if it's out of his
reach. After all, his questions on all the other threads sound like
something I would have asked 30-35 years past, and I turned out okay
;-)
True, but the MHz range would be a better place to start playing with HF
design than GHz, surely.
It's only 2.7 GHz, IIRC. Lathargic ... close to D.C. I'm envious. Back
when I was in college, they didn't have such devices as they do today
.... so easy to match and use at low GHz ranges.
I wish the guy luck - I've learnt the hard way that biting off more than you
can chew usually ends in disappointment - I suspect that I'm not the only
person here. I'm guessing that this is one of the first practical projects
of this size that the guy has undertaken and also the first thing he's tried
in HF design. He WILL underestimate the amount of time it'll take him.
Probably by a factor of 3 or more.

Having a few failures behind him will certainly improve his outlook,
not dash his dreams, IME. Trying projects beyond one's ability is the
mark of a person who will learn rapidly, IMHO.

Whatever discouraged you in the past, it sounds like you have had some
experience since. I realize you are trying to be pragmatic, but the OP
is just looking for advice on a spectrum analyzer circuit, I presume.
It's not that complicated.

Frank Raffaeli
 
Top