Detector Matching
Hello,
I am new to this amazing community. Here is my question; I am designing a
matching circuit for an RF (envelop) detector, which is simply a diode.
However, I cannot make the matching stable for various powers at BW=0.5 GHz
around center frequency of 15 GHz. Matching moves away quickly from 50 ohms
by changing the power from -50 dBm to 0 dBm.
Any suggestion or guide would be appreciated.
Thanks,
Mohammad
Hi
Not sure this is on topic for the group, but here’s the simple answer:
Your diode detector does not present a constant load as the power goes from
-50 dbm to 0 dbm. If you have a matching circuit, it can only work at one power level.
In addition, you have frequency effects.
The simple answer is not to match the detector over the whole power range. You provide
an adequate match to the rest of the system by other means (possibly an isolator, maybe something
else).
Bob
On Jan 19, 2017, at 4:00 PM, Mohammad-Hadi Sohrabi mhsohrabi@ucdavis.edu wrote:
Hello,
I am new to this amazing community. Here is my question; I am designing a
matching circuit for an RF (envelop) detector, which is simply a diode.
However, I cannot make the matching stable for various powers at BW=0.5 GHz
around center frequency of 15 GHz. Matching moves away quickly from 50 ohms
by changing the power from -50 dBm to 0 dBm.
Any suggestion or guide would be appreciated.
Thanks,
Mohammad
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
KiCad is an open source pcd cad package that looks interesting. Has some microwave/RF features, 8 layers (I think), both schematic capture and layout. Just started to look at it. Doesn't have the libraries that Eagle does, but you can create your own. Worth looking at.
Considering how Autodesk works (pay $$$$), I'm surprised that their Fusion 360 3D cad package is free for hobbyists. I use Solidworks at work, but definitely not going to pay $6K for home use. Just starting to learn Fusion 360, and, at least at my level, it seems to have all the functionality of Solidworks. My only beef is that it's cloud based, but it will work off line for a few weeks before needing to call home. My fear is that some time in the future Autodesk will either discontinue the program or start wanting $$. Again, well worth looking at.
Tom, WB6UZZ
From: Richard (Rick) Karlquist <richard@karlquist.com>
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Thursday, January 19, 2017 7:52 PM
Subject: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I think the alternative with the greatest momentum at the moment is KiCAD.
I haven’t tried KiCAD yet. The problem I have is that I have a ton of libraries and projects I’d have to convert. I suspect that there is automation to perform the import (or soon will be), but it’s basically NRE that I’m not looking forward to. That doesn’t really change with whatever option I pick, other than sticking with EAGLE. I’m not yet 100% convinced Autodesk won’t reverse course on this, unless they really do want EAGLE to die the death of a thousand cuts.
On Jan 19, 2017, at 7:52 PM, Richard (Rick) Karlquist richard@karlquist.com wrote:
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I used KICAD for my GPSDO. I've never used Eagle, so I don't know what differences there are. I had used ExpressPCB, so it did take some getting used to. Even at my early entry-level stage, a number of components supplied with the program were unusable. This was mainly due to the size of the component on a schematic being much too large. IIRC, a couple of supplied footprints weren't acceptable, either; though I can't remember which ones. And, of course, it didn't have the PIC I was using either on the schematic or the footprint for the board, as well as a couple of other smaller components. But, I've got a usable library built now, and it's easy enough to add stuff as needed.
I've only used it for 2-layer boards so far: some complex, and some trivial. I don't think the microwave trace stuff is in a completed state, yet. There is no auto-routing of the board. There were some licensing issues with the one they were using, and it was disabled and disappeared. But, you get used to picking and placing and adjusting after you've done it for awhile. It does make Gerber files that are accepted by OSHPark; who I use to make my boards.
The schematic section has the ability to use hierarchical layers. There is a 3D viewer for the routed board. I usually use that, as well as using the OSHPark pictures for final inspection before ordering.
And, the price is right.
HTH,
Bob
-----------------------------------------------------------------
AE6RV.com
GFS GPSDO list:
groups.yahoo.com/neo/groups/GFS-GPSDOs/info
From: Tom Curlee <tcurlee@sbcglobal.net>
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Thursday, January 19, 2017 11:32 PM
Subject: Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year
KiCad is an open source pcd cad package that looks interesting. Has some microwave/RF features, 8 layers (I think), both schematic capture and layout. Just started to look at it. Doesn't have the libraries that Eagle does, but you can create your own. Worth looking at.
Considering how Autodesk works (pay $$$$), I'm surprised that their Fusion 360 3D cad package is free for hobbyists. I use Solidworks at work, but definitely not going to pay $6K for home use. Just starting to learn Fusion 360, and, at least at my level, it seems to have all the functionality of Solidworks. My only beef is that it's cloud based, but it will work off line for a few weeks before needing to call home. My fear is that some time in the future Autodesk will either discontinue the program or start wanting $$. Again, well worth looking at.
Tom, WB6UZZ
From: Richard (Rick) Karlquist richard@karlquist.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Thursday, January 19, 2017 7:52 PM
Subject: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Right on their main page is a FREE download link. Eagle has always
had a free version and a paid version. The free version is limited
to 2 schematic sheets, 2 signal layers, and 80 cm2 board area. I
think this might be very slightly better then in the past.
The good news for users is that now there is a billion dollar company
behind Eagle. If they run Eagle anything like they do Fusion 360, be
prepared for a continuous flood of updates and new features.
One of the new features they are talking about is integration from
Fusion so you can make the entire product in one CAD system, At the
holy level this might be a PCB with a custom 3D printed housing so the
buttons on the PCB match up with holes on the housing. Fusion is
parametric so when an outline changes on a part on a PCB the housing
hole can move if its location was defined as "centered over that
part".
Eagle has seen very slow progress in the past, I expect the feature
set and ease of use and training materials to take off now that a big
company is tossing lots of money at it.
On Thu, Jan 19, 2017 at 7:52 PM, Richard (Rick) Karlquist
richard@karlquist.com wrote:
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
--
Chris Albertson
Redondo Beach, California
Typo: At the HOBBY level.
Professionally they make things like cell phones and set top boxes and
AV Receivers where now days the case the PCB need to be integrated and
have an ability to 3D print a prototype then send the same CAD file to
production. That is their goal. There is talk over on the
Fusion360 blog about long term goals
Another one for Eagle is collaboration. That is where a group of
designers all work on the product, basically from home and when they
are done, al the parts fit
On Thu, Jan 19, 2017 at 10:28 PM, Chris Albertson
albertson.chris@gmail.com wrote:
Right on their main page is a FREE download link. Eagle has always
had a free version and a paid version. The free version is limited
to 2 schematic sheets, 2 signal layers, and 80 cm2 board area. I
think this might be very slightly better then in the past.
The good news for users is that now there is a billion dollar company
behind Eagle. If they run Eagle anything like they do Fusion 360, be
prepared for a continuous flood of updates and new features.
One of the new features they are talking about is integration from
Fusion so you can make the entire product in one CAD system, At the
holy level this might be a PCB with a custom 3D printed housing so the
buttons on the PCB match up with holes on the housing. Fusion is
parametric so when an outline changes on a part on a PCB the housing
hole can move if its location was defined as "centered over that
part".
Eagle has seen very slow progress in the past, I expect the feature
set and ease of use and training materials to take off now that a big
company is tossing lots of money at it.
On Thu, Jan 19, 2017 at 7:52 PM, Richard (Rick) Karlquist
richard@karlquist.com wrote:
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
--
Chris Albertson
Redondo Beach, California
--
Chris Albertson
Redondo Beach, California
Another one to look at is DipTrace. The free version is 300 pins and 2 signal layers, non-profit use.
On Jan 19, 2017, at 10:52 PM, Richard (Rick) Karlquist richard@karlquist.com wrote:
Off topic, but probably a lot of disgrunted Eagle users on this list.
Its official, you will now have to pay $500 per year for a
professional license from Autodesk. The spin meistering of the
announcement would make George Orwell proud. I don't see any way they
can keep me from just using the license I currently own, at least
on the OS's it supports. (Parenthetically, like many users, I
am also digging in my heels in terms of staying at Windows 7).
Still, the question arises: are there any affordable alternatives?
Don't have to be entirely free. I am looking for any trends out
there as to what tool will attract a critical mass of users in
the future. There is strength in numbers.
Comments?
Rick N6RK
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
In message d8ffe915-97aa-e1ef-6655-7b3f706bc0f7@karlquist.com, "Richard (Rick
) Karlquist" writes:
Still, the question arises: are there any affordable alternatives?
KiCad!
Open source, and actively maintained and developed by CERN.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.