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W3AXL Posts

Panatap Update: Living in the Real World

Hi all! Just a quick update in regards to the responses I’ve received for my Panatap board.

First off, thanks to everyone who’s given me positive feedback for my design. I really appreciate everyone who has found my design useful, and I hope that future projects that I’m working on will be just as helpful.

One thing I wanted to address is a question that several people have commented or emailed me about: component values. Specifically the values of the capacitors and inductors used in the low pass filter. The values I specified in the schematic and in the board file are the raw values that came directly from the filter calculator linked in my previous post. Many of you noticed that it is neigh on impossible to get components at these values, and while I knew that as I was designing the board I never really bothered to actually update anything to reflect real-world values that could be used. As of today, I’ve updated the files on the github project to reflect the real component values that I used in the construction of my boards. In addition, I’ve added a new file with Digikey part numbers for all of the parts involved in the construction of the board. Hopefully that gives you guys a running start on constructing your own boards. I also added the LTSpice simulation file that I used for testing the original circuit for you to play around with if you’d like.

That’s all! I’m super happy that people are actually getting use from my design, and I hope that this project inspires you to dive into the world of RF PCB design for yourself.

73

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W3AXL Panatap: We Are Go for Liftoff!

Hello again everyone! I apologize for the lack of updates. School, as it often does, got in the way once again and I haven’t made real progress on any of my own projects in just under a month now.

Luckily that all changed recently. With nothing better to do on a Saturday night, I set forth a goal of completing the new revision of the redesigned G4HUP panadapter (what I’m now calling the W3AXL Panatap) and getting it installed in my FT-450D. This proved to be both easier and more difficult than I thought. Details inside!

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Panadapter on a budget! Revival of the G4HUP PAT Board.

NOTE: Check the latest blog post for an update on the below information!

I recently acquired a shiny new Yaesu FT-450D. I knew almost immediately that I wanted to use one of my many RTL-SDR dongles to set up a pandapter. As luck would have it, all the hard work was done for me by Dave Powis, G4HUP. He had designed a compact, high-impedance IF tap for direct connection to any SDR. Unfortunately, with the passing of Dave came the end to all shipments of the PAT board, leaving me high and dry in the search for a cheap way to add a panadapter.

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Updates & Wiki

Hi all! It’s been a while since my last post. School and life has kept me plenty busy, but I’ve been trying to get a few new blog posts up. It’s hard to dedicate enough time to get quality content…

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Building a No-drill Antenna Rack for Your Car

There comes a time in some hams’ lives when they’re faced with a dilemma. They can’t drill their car, the mag mounts are getting old very fast, and trunk lip mounts just won’t cut it. The misguided of the lot go towards glass-mount or fender-mount antennas, and settle for poor performance and high losses. The more adventurous, well, we get creative. So if you’re like me and you want to mount a whole bunch of antennas to your car but don’t want to drill the roof, this is the story you want to read.

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The Comet RS-720 NMO Mount – A Review

DISCLAIMER: I’m not paid for any reviews I write. Hell, I wish I was; it’d bring in more money for fun radio stuff. Be assured my reviews are 100% my own stream of consciousness.

There has never been a more controversial topic in ham radio than that of mobile antenna installations. Half of the world thinks that everything can be solved with a good hole saw through the roof. The other half is reasonable and understands that sometimes that isn’t an option. Let me preface this by saying that yes, in most situations a drilled and sealed NMO mount properly installed will outlast and outperform any temporary mounting method. However, for those of us who aren’t able to permanently change things about their vehicle, be it for rental or lease reasons, or maybe your significant other just doesn’t want any holes in the car. Regardless of the reason, just because you can’t drill doesn’t mean that you have to settle.

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The Motorola Railroad Spectra – part two

So here we are again. Same radio, different day. In our last adventure, we discovered that my newly acquired Motorola Spectra Railroad Model was stuck in a boot loop with the FAIL 01/90 error code, the general hardware fault code. Unfortunately, it was not going to be as simple as program and go with this radio.

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The Motorola Railroad Spectra – part one

As well as being a ham radio operator, I also am a huge rail buff. As such, I had long wanted to add a railroad radio to my collection. Unfortunately, the only ones to be found for sale were either old radios from the 80’s with limited feature sets, or newer Astro radios from the big M that were way more than I was willing to pay for a radio.

Fortunately I was able to stumble on a for-parts Motorola Spectra on ebay for a very, very decent price with shipping. The radio was advertised as untested, but pulled from a working environment. I jumped on the item and within a week it was at my door.

So began a not-so-fun journey into the mystical ways of railroad-grade equipment and poor documentation.

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Tytera MD-380 Initial Impressions

DMR is the hot new digital mode that everybody seems to want a piece of, even though it’s been around for several years. The real reason everyone’s been jumping aboard is the rise of inexpensive DMR portables, specifically ones like Tytera’s MD-380.

For $170 US you get a fully functional UHF digital radio that can do both conventional analog 70cm as well as DMR communication. Previously radios like the XPR line from the big M were going for upwards of $500 used, so this is a welcome price drop. It’s not unlike how Baofeng revolutionized entry-level radios a few years ago when they came out with a dual-band HT for $35. Now people with a modest budget will be able to get on DMR repeaters and talk to people all over the world, without a costly HF rig.

I was able to get my hands on one of the 380’s for cheap and have been playing around with it for the past few weeks.

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