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Amplifier breakout board

I’ve finally gotten around to assembling a breakout board for the Skyworks SKY65116 UHF amplifier.  It’s really amazing how the state of the art in RF ICs has advanced.  They can still be on the expensive side ($6 at digikey), but still relatively cheap when you consider the cost of all the support parts that it takes to build an amplifier from a RF transistor.  This particular amplifier has a 50 ohm input and output, and 35dB of gain.  It works from 390Mhz to 500Mhz, which means its perfect for the 70cm ham band.  The breakout board is stupid simple, copied directly from the evaluation board schematic in the datasheet,  but I’ll include schematic and design files anyway. Read more…

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Transciever enclosure

It has been a while since I finished the transceiver modules, and I how now used them in an actual application.  But, before I talk about that, I’d like to show some pictures of the process I used to put them into enclosures.  I had some of these cast aluminum enclosures lying around, so I thought I’d use them.  They’re a little on the heavy side, as the completed weight is around half a pound, but it’s well within the carrying capacity of my Kadet. Read more…

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Mud Bug flying

I maiden’d my new plane, the Mud Bug, last weekend!  I was a ton of fun.  Now, I’ll tell you all about building it, and converting it to use brushless motors. Read more…

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Unsuspecting security camera

Well, as a (perhaps welcome ) deviation from the spectrum analyzer posts, I’ve spent a little time working on repairing a security camera I’ve been hanging onto for a while.  I’ve been toying with the idea of installing it near the radio control flying field as someone in the club knows the owner of a nearby business.

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IF Amplifier cooling down

I’ve decided to hold off posting spectrum analyzer modules until they’re complete.  I’ve been collecting tons of pictures along the way, so hopefully the post for each module will be interesting and visually appealing.  With that in mind, I can’t post about any of the modules with the exception of this one.   Read more…

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IMPORTANT!!  – I’ve made a special page for my construction and testing of the spectrum analyzer.  It’s available on the navigation bar below the blog title banner, or here.

A while back I bought a spectrum analyzer kit.  It can display waveforms in the frequency domain from 0 to 1000 Mhz.  I haven’t worked on it for a while, but I’ve decided to start working on it again.  If you’re interested in more information, there is a webpage for the analyzer by the guy who designed it, and there’s a Yahoo group, also. If you’re really-really interested there is a group buy open (until the 28th of march 2010) here.  Anyway, I’m sure it’s of limited use to my usual readers (thanks, friends & family! [oh who am I kidding, most of my family doesn't read this ]), but it may be useful to others working on the kit.  I’ll post the “annotated” CAD images for each board here, and add images of the completed boards when I finish them.  Who knows, it may be interesting for someone.  Also, I’ll include my thoughts and observations while building these boards.  Finally, not all the boards that come with the kit include annotated layouts, so I’ll have to dig around and figure out what they do and what to put on them Read more…

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Comparing antennas

I’ve finished building the first (and my first) Yagi antenna for the Kadet video downlink.  I mentioned in the first video post that a new, and better, antenna would help greatly. Read more…

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The weather sucked, but I was able to get out the the field this morning. I recorded about 17 minutes of video in total.  In the embedded clip, I edited out the majority of the static.  I’m a little disappointed that the signal quality is so poor.  I found a site that has some cheap Yagi antenna designs in 50 and 75 ohms.  I’ll probably try to build one this week and see how it goes.

More information about the camera is available in these posts, if you haven’t already seen them.

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Painted to match

Taking advantage of the crummy weather, I decided to paint the camera module to match my plane.  I didn’t just do it for the aesthetics, no really, I swear.  Actually, the real reason I painted it was to prevent stray light from making annoying reflections on the inside of the window.

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Camera installed with Transmitter

I’ve just finished building a camera module for my Kadet.  When I was building the plane I knew that I was going to try and put a camera and transmitter approximately where the pilot’s head would be in a real plane.   Read more…

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