Playing RTTY radio

Spent a couple hours yesterday afternoon out at the club communications trailer for the ARRL Rookie Roundup (RTTY). Tom (AJ4UQ) set up one of the club radios, a Yaesu 897D and one of the laptops to run RTTY.

ARRL Rookie Roundup (RTTY) 2013 from the CARS trailer
ARRL Rookie Roundup (RTTY) 2013 from the CARS trailer
Radio set up for ARRL Rookie Roundup (RTTY) 2013
Radio set up for ARRL Rookie Roundup (RTTY) 2013

There were two other rookies that came out, James (KK4REM) and Andrew (KF7YOX). We operated using my call sign this year and after Tom showed us the basics and helped set up some macros in fldigi, we were off and running.

ARRL Rookie Roundup (RTTY) from the CARS Trailer
ARRL Rookie Roundup (RTTY) from the CARS Trailer
KK4REM (right) and KF7YOX (left)
KK4REM (right) and KF7YOX (left)

The radios and laptop were initially set up to run off the batteries in the trailer, but after a few minutes, we noticed the voltages displayed by the radio were getting pretty low. A quick look revealed the batteries had gone dry for some reason despite having been topped up a couple of weeks ago. They were also unusually hot even after they were refilled with water. Some of the more knowledgable people suspected a problem with the charger not reducing the power once the batteries were charged. We managed to find a long extension cord and switched over to wall power.

This highlighted another purpose for these “contests”: it gives you a chance to exercise your equipment and discover problems, especially important for something intended to be used in emergency/public communications purposes.

After getting past that, we started hunting around the bands looking for other people playing in the Rookie Roundup. We wandered around several bands, learned how to adjust and tune the antenna (a Little Tarheel) and a bit about how to use the radio. We found a few people and made a handful of contacts, but it seemed like it was easier to hear them than to make contact with them. We decided that maybe the antenna didn’t have a good enough ground plane, and Tom thought that maybe some radials would help. That’ll be something else to try for later.

I think in the 3 hours or so that we were operating, we made about 5 or 6 contacts. More importantly, I think the three of us learned a little more about radio operating. I learned a little more about the inner workings of the trailer and a little more about the different digital modes. We got to hear several different types of digital modes, including some PSK signals.

Overall, even though we didn’t make a lot of contacts, I think it was still a pretty good time. Got outside to play radio, worked with a couple of the newer hams, all great fun.

Now I want to see if I can build my own interface so I can do digital modes at home.

ARRL Rookie Roundup (RTTY)

Coming up this weekend (Aug 18) is the ARRL Rookie Roundup (RTTY) which I’m planning on participating in. Like last year, we’ll be using the club’s communications trailer and setting up at the old fire station off Dorchester Road (6938 Dorchester Rd) by the Air Force base.

Not sure who’s call sign we’ll be using yet but hopefully the bands will be in decent shape and we’ll be able to make some contacts.

Repeater work

A few days ago I joined some of the local club members at one of the club’s repeater sites that just happens to be located on top of one of the buildings at work. The two repeater controllers were due for firmware upgrades, but my task was to look at the IRLP node, see if it was still running, find out what it was running, make a copy of the software and get remote access to the machine working. I’ve never done anything with IRLP before, but my job was pretty simple.

The equipment is located in the “penthouse” of a 12 story building that houses all the ventilation equipment for the building, making it a fairly noisy place. The club operates VHF and UHF repeaters each in their own cabinet.

Repeater cabinet
Repeater cabinet
Resonator cavities
Resonator cavities
Resonator cavities
Resonator cavities

The IRLP node was an ancient Dell computer sitting next to the repeater cabinets. After attaching a keyboard and monitor to the box, I found it running Fedora Core 3 and spitting out disk errors to the console. Trying to log in to the computer just caused more disk errors to be spit out. Rebooting confirmed that the disk was dead and unreadable. So much for working on the node. Now the job became one of hardware recovery. Took a bit more effort than I expected, but I was able to pull the hard drive and the IRLP board out of the computer. One of the other club members is going to try to rebuild the node using newer hardware, maybe a Raspberry Pi IRLP node (PiIRLP).

On the way out, I got a couple of pictures of the great view from 12 stories above Charleston. This is looking west towards James Island and West Ashley. You can see the James Island Connector in the background.

Rutledge Tower view
Rutledge Tower view

This is looking east-ish at the rest of the peninsula.

Looking east-ish from atop Rutledge Tower
Looking east-ish from atop Rutledge Tower