FreeDV is a fully open digital voice protocol; unlike DMR, D-STAR and the rest, there are no patents tying it down. It uses very little bandwidth for voice. I just had my first QSO (thanks K5WH in Texas!) using this mode. While it does make voices sound a little robotic, there’s no static, no hiss, nothing unwanted. That’s what always put me off HF voice: trying to work out who is saying what through all the noise. FreeDV fixes that.
It’s quite a new protocol, so you don’t hear it much on the air yet. I hope to be making some more noise with it soon.
So I’ve just got my digital mode setup working again. It seems that somewhere, somehow, a driver for the SignaLink USB decided to stop working, and at best I got no signal on transmit and a very very quiet one on receive. Now my mind’s back in radio mode, I realise there’s a ton of stuff I’ve bought and found to be of variable utility. This is the good stuff:
Rigblaster Pro: this audio interface is far larger and far more expensive than it needs to be, but I got it used for a good price. Coupled with a $3 (!) USB sound card, it makes a sensitive and controllable sound device. I think I now prefer serial PTT-controlled audio interfaces to the SignaLink’s vox-style “Make a noise and I’ll transmit it” mode. It means you won’t accidentally tx system noises. That’s worth having another USB cable lurking about.
LDG autotuner: because of the wild and pointless diversity in radio interfacing, LDG makes a bunch of autotuners for specific radio models. Mine just works, and will tune my mini-G5RV from 10 to 80(ish) metres.
Big external meter: a cheap LDG meter is way better than the fiddly bar graph on the front of my FT-857D. I have it set up for signal on receive, and perhaps slightly unusually, AGC on transmit. Since I have a tuner and run almost entirely digital modes, it’s important that my signal doesn’t distort, so seeing AGC and being able to tweak it is important.
Heil Pro-Micro headset: this is comfy, and keeps the family sane. I have the footswitch too, which really helps to run nets.
Quarter-wave dual-bander HT antenna: The rubber ducks that all my HTs have are a bit rubbish. A simple replacement antenna allows me to talk through fairly distant repeaters from my sheltered back garden.
WinKeyer USB: I’m just starting morse. The WinKeyer kit was so well put together it was a delight to build, and seems to be an utterly sound keyer.
Fldigi: the digital mode program. Reliable, full-featured and free. It basically runs all the time on my shack computer.
Chirp: I can program all my HTs and my HF rig with this. It’s truly great, and miles better than proprietary programming software.
PSKReporter: a few minutes after calling CQ, I can see where in the world I’ve been heard. This automatic reverse-beaconing site is magic, and I’m amazed that a lot of digital users don’t even know it’s there.
My one annoyance about having a Linux-based shack is that ham radio is still very stuck in using serial ports. None of my computers have hard-wired RS232 ports, so I rely on USB serial adapters. These mostly work well, but Linux has a habit of shuffling the allocations around, so what was /dev/ttyUSB0 controlling your rig today might be ttyUSB1 tomorrow. You can get around this (if the software supports it) buy using long serial device names from /dev/serial/by-id/, which don’t change. They don’t change, that is, unless you have two Prolific serial interfaces that don’t have serial numbers set, so I can only have one attached at a time. Annoying.
Looks like this amateur radio thing is going to get expensive.
The rig I was looking at — the Yaesu FT-8900R — appeared to be considerably cheaper than all the other multi-band units. It appears that it’s FM only, which is rarely used on the HF bands. The considerably more expensive FT-857D is the cheapest unit that will do 10m/6m/2m/70cm, which I reckon is pretty much where my interest lies.
Then there’s power supplies. Yeah, these beasts need external power supplies. Great big honkin’ 13.8V DC power supplies; about $200 for a rig of this size. Yet more desk space taken up; more cables, more clutter.
If that weren’t enough, there’s the antenna issue. I appear to live in a Faraday cage surrounded by overhead TX lines. Something’s going to have to go on the roof. Well, actually two somethings, as the chance of getting an antenna to work even roughly well on HF and VHF (unless I splash on the expensive and fiddly looking Maldol HVU-8) is close to nil.
So basically, I’m looking to drop a couple of grand on this. Eep.
In better ham news, last night I received my first radiogram, welcoming me to the hobby. Thanks, Paul (VA3PB)!
It’s highly likely I’m doing something wrong, but I’m getting nothing on the 2m & 70cm bands in eastern Toronto of an evening. After a week of dedicated listening, I’ve stumbled upon a couple of nets (one of which I briefly participated in), heard one morning commute chat, noted a couple of dudes talking about power supplies in Portuguese, and managed to key up a repeater which said hello back to me. That’s it.
I’m not expecting the airwaves to be crackling with witty repartee all the time, but most of the time there seems to be no-one out there. Calling CQ on simplex VHF might as well be shouting into a hole.
I know I have a cheapo rig and a flimsy aerial, but I must be able to contact people within the neighbouring kilometres … must I?
I just got my amateur radio license. If you’re unlucky enough to be on the 2m and 70cm bands around Toronto, you may just find me as VA3PID. The 3 is, of course, silent …
I guess that (so far unsuccessfully) futzing around with the small digital transceivers with Arduino made me look up some radio things, then I read this article on MetaFilter. It made me realize that unless new hams get on the air, the hobby will die, and the radio spectrum will be reallocated.
Passing the test wasn’t that hard, but did take a bit of dedicated reading. No morse code is required for the Basic Amateur Radio Operator Certificate, and if you get more than 80% in the multiple choice test, you can use the HF frequencies below 30 MHz. Since the pass mark is 70%, I thought it worth the extra effort.
I slightly overbought on the study materials. I got:
HamStudy Basic, plus the RAC Operating Manual (plus a year’s membership to the RAC)
While it’s possible to download the question bank from Industry Canada, or use the quaint Windows-based examiner program, I thought I’d work from a book. Both will likely do pretty well, but neither is perfect:
Both books need to work on their proof-reading.
Mathematical symbols, superscripts and subscripts are easy to typeset these days. Don’t miss them out.
They need to be fully metric, as trying to remember weird factors to convert fractions of a wavelength to feet is annoying. I’m a mid-career engineer, and I’ve never had to use anything but metric.
I passed the exam on Tuesday night, and had my callsign listed by Friday. I have a cheap but adequate Wouxun dual band HT. This should be fun.