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Ben Sinclair's avatar

Using an Apple Keyboard with vim

I've recently been trying to upgrade my development environment with a better vim setup, and by incorporating tmux. All of the cool kids use tmux these days, so I thought I'd try it out.

In getting vim up to speed, I realized that my Apple bluetooth keyboard doesn't work well for keyboard-shortcut intensive work. The main problem is the lack of a right control key.

The easy fix is to use Karabiner, which lets you customize your keyboard and mouse settings at a very low level. I was able to increase my key repeat rate beyond what OSX allows, and I remapped my right option key to control, and now I'm much happier!

If Apple made a modern version of their old full size wireless keyboard, I'd be even happier!

Update: I didn't realize that iterm2 lets you remap the right option key, so I'm using that now rather than run Karabiner just to remap one key. You can also use the OSX keyboard settings to remap caps lock and get a third control key!

Ben Sinclair's avatar

A New Oscilloscope

Oscilloscope

I finally found a cheap and functional oscilloscope! Here it is showing my 6502 running its single instruction over and over. The top trace is the clock, the bottom trace is one of the address lines.

This should make things easier! Next up I need to find a logic analyzer...

Ben Sinclair's avatar

Remote Control for the MFJ-1788 Loop

I've enjoyed using my Flex 6300 on wifi from anywhere in the house for digital modes and SSB with SmartSDR 1.4. However, my MFJ loop antenna needs tuning every time I change frequencies, which requires a trip back down to the radio.

Being lazy, I wanted to be able to remotely tune the loop. My first thought was to add relays to the control box switches, but the schematics aren't available, and I didn't want to damage anything. Instead, I went for the ugly, but fun, hack of using a servo to press the buttons!

Loop controller hardware

The servo is attached right over the slow tuning buttons using some metal brackets. On the servo is a horn, much like the type used for remote control aircraft, which just happened to be the right size to hit each button.

I'm just using one servo, and all it can control are the slow tuning buttons. That's not a problem with the Flex as I can visually see where I'm tuned, and don't really need the automatic tuning features of the control box. Using the slow buttons takes a while, but it's not too bad.

The servo is controlled by an Arduino, which is then controlled over serial by a Rails application. With a web application I can easily control it from almost any device, and could set it up for WAN remote in the future.

Loop controller interface

The first row of buttons stops and starts continuous movement of the tuner. The other buttons make short movements for fine tuning. There is a slight delay as the servo moves, so having the ability to do short button presses makes it easier to get the tuning just right.

It's a fun hack, and it works!

Ben Sinclair's avatar

K1N!

I finally made a contact with K1N, the DXpedition to Navassa Island. Navassa is the second most wanted DX entity, after North Korea.

Using the "Flex Advantage," I was able to follow where they were listening, and transmit right near a previous contact. Once I started doing that I got in pretty quickly.

I got them on 18mhz CW. I'll keep trying on other bands and modes while they're still on the island.

Calling them for hours was tedious, but it was a real rush to hear my callsign come back!

Update: People were asking me what the heck I'm talking about, so I'll give a quick explanation.

A fun amateur radio challenge is trying to make contact with as many distant places as possible. There is a list of geographical entities, consisting mainly of countries, but also islands or other geographically separated places, that count as separate entities. Many of these entities are major countries, which are easy to contact. Others are uninhabited or restricted somehow, so there just isn't anyone there to contact.

If you want to contact every distinct entity, you'll have to somehow make a contact in these remote or restricted places. The most wanted place is North Korea, which doesn't grant amateur radio licenses. The second most wanted place is Navassa Island, near Jamaica, which is on the air right now!

Navassa is a tiny, uninhabited American island, and is a restricted wildlife refuge. A team of amateurs obtained permission to go and is on the island right now making contacts all over the world.

This probably won't be allowed again for decades, so it's a pretty exciting!

Ben Sinclair's avatar

Radios, radios, radios!

Over the past month I've bought and sold a few radios in an attempt to find something I really like. Here's a short history of radios I've owned recently and some thoughts on each one.

These are mainly thoughts from a user standpoint, not quantititive testing or anything too fancy. I used all of these with my MFJ-1788 40M-15M magnetic loop.

IC-7100

IC-7100

I purchased an Icom IC-7100 in December, 2013, and used it all of 2014. It's a great radio, and covers HF, VHF, and UHF with all modes, including D-Star. It's designed to be a mobile radio, but I've only used it in the shack or camper on a desk. The touch screen is nice, but would be difficult to use in a vehicle.

Pros:

  • Built-in USB serial and sound card. Run digital modes with just one cable.
  • HF, VHF, UHF all mode.
  • Good screen with the ability to display lots of meters at the same time.
  • Automaticly sets up the nearest D-Star repeaters using a GPS.
  • SD card slot for recording audio, D-Star QSO logs, and saving/loading settings.
  • Looks great on a desk. The radio itself can be placed out of the way, and the mic, key, and headset can connect to the head unit.

Cons:

  • Lack of physical controls requires multiple taps to adjust settings.
  • Tuning the MFJ loop takes too long (switch to RTTY, tap to enable power adjustment, lower power, tune, rinse and repeat).
  • Probably not great for mobile, but I only used it as a base station.

The IC-7100 is really a nice radio, but I'm always adjusting things to tune and pull out weak signals. Touch screen with just a few knobs was cumbersome for quick changes.

IC-7410

IC-7410

For Christmas 2014 I bought myself an Icom IC-7410. It only covers HF, so I planned to keep the IC-7100 for UHF/VHF. This is a big radio with a very nice, crisp screen, and lots of buttons and knobs. The IC-7410 has a dedicated power control, which I always find handy as I like to keep power low and adjust as needed.

Pros:

  • Like the IC-7410, it has built-in USB serial and sound card.
  • Lots of buttons, knobs, and a big display. Everything I frequently adjust can be done directly.
  • Great noise reduction. This radio has the best NR I've used so far, at least compared to my IC-7100 and other older radios.

Cons:

  • The screen is nice, but compared to radios like the Yaesu FT-DX1200, the black and white just seems a bit dated.
  • Doesn't have a receive-only antenna input, which other radios in this class have.

FlexRadio

IFlex 6300

I really enjoyed the IC-7410, but the other day at lunch I was talking with some friends about the newer FlexRadio models. I have no idea why I never thought to try them before, but my friends were very convincing. As a test I ordered the somewhat inexpensive, but older, Flex 1500.

Wow! I've always had an RTL SDR with an HF upconverter, which is fun, but not a very good receiver. I setup my station to let me flip back and forth between the IC-7410 and the Flex 1500 and try various settings, filters, etc. The Flex 1500 was consistantly better able to pull out weak signals. The panadapter, even though it's only 48k wide on the 1500, was amazing.

After playing with the 1500 for a few days I was hooked, but wanted more than 5W. I ended up selling the IC-7410 and the IC-7100, then ordered a Flex 6300.

I'm just getting started with the 6300, but it's incredible. It will show up to 7mhz on the panadapter, and seems to receive as well as the 1500, if not better. Tuning the MFJ loop is easy! I just zoom out the panadapter and can visually tune it almost perfectly. It also has a tune button with a separate power level adjustment. It drops me quickly to a few watts and transmits a tone for tuning, then returns to where I left off.

The 6300 connects via ethernet to my local network. I can be anywhere in the house and run the radio from my MacBook (under Windows 8.1). I've previouly used VNC to run digital modes off the laptop, but with the 6300 it's a direct connection to the radio, and I run a local copy of SmartSDR (the 6300 control software) and fldigi.

As many have noticed, SmartSDR is not as mature as PowerSDR (on the 1500), but it should get better. A new release is expected this Friday, so I'm looking forward to trying it out.

I'll say more about the 6300 after evaluating it a bit longer, but already I can't imagine going back to a traditional radio. I'm keeping the Flex 1500 for portable use in the camper, so I'll always have an SDR with me!