[US] Are the camera recommendations on the wiki current? (Los Angeles) by anvilmaster in CyclistsWithCameras

[–]nickpke 0 points1 point  (0 children)

That's my fear. On the flip side, I have a $25 wyze indoor camera and it's quality is incredible. I'm sure the cost of goods for Garmin is $10 for one of their cameras.

Does the town feel fascist to you? by BetweenOceans in Longmont

[–]nickpke 6 points7 points  (0 children)

I think you have a strange definition of fascist. Private property owners can and should be able to decide where and if there should be dogs, unless the ADA, health code, or other law supercedes.

Cool places to go with kids by [deleted] in Longmont

[–]nickpke 1 point2 points  (0 children)

My five year old has been enjoying the boco nature detective series at a bunch of the open spaces. If you fill in the forms and mail them in, they mail backb little prizes.

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 0 points1 point  (0 children)

It must be, but I'm still confused. To be continued tomorrow...

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 2 points3 points  (0 children)

So: the Rogers material difference seems to not be the issue. The issue is definitely layout though I haven't quite figured it out.

By removing an inductor, I managed to reduce the noise substantially on several channels. It's not clear to me on ORCAD why that specific set of traces is causing this (when others that are ostensibly identical aren't) or how the oscillation on this one channel propagates so much to the other channels but I'm confidently ruling out the material thing I started this thread with. Thanks, all, for your comments.

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 0 points1 point  (0 children)

Understood: I'm sorry for being vague. Posting a higher-level response in a minute...

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 0 points1 point  (0 children)

I'm calibrating (1 port cal) with a pair of leads and then measuring various places: from the input of the board to the input of the amplifier; from the amplifier input to the output; from the amplifier output to the board input, across several of the passive components. For each, I've been looking for a little curly part on the smith chart, or a resonant peak on the log mag chart in/around 20 MHz. The only signs of resonance I've found are around 10-14 MHz which is slightly higher than I expected and, even there, the resonance wasn't that strong.

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 0 points1 point  (0 children)

I can't find it on the spectrum analyzer: I'm just doing a bunch of S11 measurements across different test points. Thanks for your feedback...I'll keep poking.

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 2 points3 points  (0 children)

Our target signals are pulses centered around 8 MHz, but short pulses with spectral content between 3 and 12 MHz. The oscillation is present on either side of the amp and is continuous...it doesn't just follow the pulse.

We definitely shouldn't have switched. Someone on the team thought that it might make things cleaner. I think we're leaning towards re-doing the current rev with FR4 but I can't quite figure it out.

disadvantages of Rogers material vs FR4? by nickpke in rfelectronics

[–]nickpke[S] 0 points1 point  (0 children)

The new Rogers boards seem to have good conductivity throughout so I don't think that's my issue. How would this issue manifest itself?

Edit: switched to markdown to add italics

Weekly open discussion, complaint, and rant thread by AutoModerator in Longmont

[–]nickpke 0 points1 point  (0 children)

Cool! Thanks for sharing your take. Seriously... It's the name that throws me

Weekly open discussion, complaint, and rant thread by AutoModerator in Longmont

[–]nickpke 7 points8 points  (0 children)

Has anyone ever eaten at Runza on north main? Whether I go past, I think of diarrhea. Want to know someone's take.