Copyright: 1996 - 2024
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
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Troubleshooting The example Mixer Project - RF Cafe Forums
RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media
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August of 2003 and was quite well-attended for many years. By 2010, Facebook and
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Forums activity dropped off precipitously. If the folks at
phpBB would release a version with integrated
sign-in from the major social media platforms, I would resurrect the RF Cafe Forums,
but until then it is probably not worth the effort. Regardless, there are still
lots of great posts in the archive that ware worth looking at.
Below are the old forum threads, including responses to the original posts.
|-- Amateur Radio
Gripes & Humor
-- CAE, CAD, &
Test & Measurement
Post subject: Troubleshooting The example Mixer Project
Posted: Thu Oct 06, 2005 4:22 pm
May 09, 2004 1:23 am
Location: Morgan Hill, CA (Silicon
Valley, Bay Area)
Okay, I decided to drive home for lunch so that
I could gather a few screen captures (I am lucky in that I live and
work in the same town).
Below is a schematic of the example
design (SweptRF.dsn) from the Mixers_prj project and below this we see
graphs of the resultant simulation.
As stated in my last post
I've only added one net at the LO port of the mixer and named it "VLO"
then I produced a plot of the VLO and Vrf (verses swept RF frequency,
Frf) as shown in the graphs below. The third screen capture shows the
As can be seen from these graphs the project appears
to be running correctly, but when I try to look at the signals going
into the mixer I do not see anything that would make sense. In the graphs
RF power should say -20dBm at 1GHz and LO power should read -5dBm at
1GHz-70MHz= 930MHz, but as the two graphs show LO power is below -50dBm
and RF power is below -60dBm.
Perhaps the graphs that I have
drawn take frequency samples that do not sample exactly at 1GHz and
930MHz thus explaining absence of power. I do not know.
Post subject: Posted:
Thu Oct 06, 2005 4:25 pm
Joined: Sun May 09,
2004 1:23 am
Location: Morgan Hill, CA (Silicon Valley,
Opps! I screwed up. This posting was supposed to go under
"ADS using Harmonic Balance with mixers," but I've created a new post
If anyone can move this message for me (or delete
it so that I can repost in the correct area) I'd appreciate it.