Mixed Modes?

While listening to the local traffic net tonight, I thought about the inefficiency of moving traffic by voice.  I appreciate that if it's all data, it's email, not traffic, but a thought occurred to me ...

What if we had easy support for "mixed mode" radio: where you start out on voice, but when both the sender and receiver are ready, the sender switches to data to squirt a file.  Radiograms are very short, data-wise, and the length of a 1200 baud message would be very short.  With Forward Error Correction (FEC), you wouldn't need a hand-shake protocol; the receiver would look at their software and say either they got it or they didn't, and retries could be coordinated by voice.

I appreciate the value in still doing it all by voice, but I also think that a mixed mode would be useful in a lot of ways beyond just traffic nets...

Chat Roulette and Ham Radio

Imagine a new sensation everyone is talking about.  With this new application, you can connect with and talk to random people all over the world.  You never know who you are going to get to talk to, which is part of the fascination people have with it.

Wow, sounds like Ham Radio! Except it's Chat Roulette, the latest Internet fad...

Panasonic offering ultra-high capacity batteries in 2011?

From TFTS:


New Panasonic Lithium-Ion Battery to Power Up a House [New Li-Ion Battery Coming from Panasonic in 2011]

Panasonic is going to create one of the hottest batteries available to date. The new lithium-ion storage cell should power up a whole house in 2011 when it could be available to the general public. I don’t know about you but I’d want to plug that battery right into my laptop and see how much life it will be able to offer me.

Furnio Otsubo, president of Panasonic said that the new battery should offer sufficient electricity for about one week of use. That’s certainly something I could get used to although I bet the new battery concept is not going to be that affordable.

Read the rest at...

http://nexus404.com/Blog/2009/12/24/new-panasonic-lithium-ion-battery-to-power-up-a-house-new-li-ion-battery-coming-from-panasonic-in-2011/

PSK31 ... fun mode, boring conversation

So it seems almost everyone's PSK31 conversations are driven by the macros in the programs.  I can frequently tell what program people are using by the pre-fab comments they send.

I thought hams were into ragchewing? It seems like if I ask a question that isn't answered by a macro button, I just get

de 73 and thanks for this QSO on , good DX in 2009. de sk

and the conversation (such as it is) is over...

Emergency Power and the VX-170 HT

I picked up a 5AH battery and a charge controller from All Electronics to assemble an emergency backup power supply for my VX-170 HT, and when I tested it was surprised at what happened...

According to the manual for the HT, standby current was 20.5 ma (in saver mode), so I figured a drain of 20.5 maH on a 5AH battery should last about 11 days.  So after I charged up the battery and put the HT on it (just on saver mode), imagine my surprise when it drained the battery in a day.

Turns out that with the battery pack installed, and even with the battery pack fully charged, having the battery pack in the HT increased the current drain to nearly 200 ma, giving me my 25 hour life!

I've now pulled the battery pack and just run the HT off the SLA (Sealed Lead Acid) battery, and so far the voltage on the battery is holding up much, much better.

In an actual emergency, I expect the the drain to go faster, and have budgeted 20 minutes per hour of standby, 30 minutes of reception, and 10 minutes of transmission, 12 hours a day, for a life of about 6 days on the SLA (with then about 2 more days on the internal battery).  That gives me 8 days, which should be enough to get some sort of power back online...

Random Hacks of Kindness

If you go to http://www.rhok.org, you'll see an event that took place with software developers and groups involved with disaster relief.

Here's an article on the event: http://news.cnet.com/8301-27080_3-10398073-245.html

Other than some comments by readers of the article, there is no mention of amateur radio. Which is kind of interesting, because first place went to an application that relies on cellular phones to work. Well, I guess we'll see how that works out in the next disaster.

Wide AF SSB Radio for Digital

Doing digital over SSB HF is pretty nifty. Your computer essentially processes several channels of data at once, and allows you to monitor several QSOs. When you transmit, even though the radio is capable of transmitting a 2.5khz wide signal you only send a few hertz, allowing you to drop in your signal inbetween everyone else's.

In many ways, it's a software defined radio -- the real radio is just dropping a 2.5khz wide band of HF down to audio frequencies to make it easy for the computer to deal with.

But 2.5khz isn't really optimal for digital, it's optimal for voice. And as far as making do with existing technology, it's great.

But why not build a digital-oriented, low cost (!), SSB transceiver that passes through 10khz of bandwidth instead of 2.5? It would be useless for voice, for sure, but since sound cards can digitize at 44khz they'd have no problem with 10khz of spectrum all at once. Even 5khz of AF bandwidth would be twice as useful!