Stop trying to shoehorn DRM into everything under the sun

Since Disco Palace is once again absent from the airwaves, here is another totally unhelpful collection of words.

How did mediumwave AM for emergencies lead to DRM providing a smartphone experience? Drugs: just say no to them. For one, you don't need to be connected to the internet to use a smartphone (i.e. playing games). For another, the whole social aspect of certain apps is incompatible with the unidirectional nature of broadcasting.

But confusion over whether DRM delivers cute kitten videos and tweets in an emergency aside, let's look at the current infrastructure that provides said smartphone experience, in a country with reasonably current wireless service.

If I've got a smartphone, I want to see at least 3G speeds. As a baseline, that means HSDPA. At the most pessimistic channel profile, I can expect 1.2 Mbps downstream with a 5 MHz channel.

Now what might I expect out of DRM with a 20 kHz channel? If I assume that I have a great channel, high SNR, and puncture the hell out of my convolutional code, I get...

72 kbps

That's what, like two dial-up modems? And bear in mind that reality says there will be loss, so unless you want to piss off your audience, you'll have to periodically re-broadcast data, a la Teletext. And at that data rate, text might be all you can realistically expect to broadcast.

(The entire AM band in America, from 540 kHz to 1710 kHz, is 1.17 MHz wide. Just saying.)

But let's assume that you magically have data in your radio. Now what? Well you have to process it and display it, don't you? Wait, isn't that what a smartphone does too? Are you really going to beat a smartphone on power consumption when you're doing exactly what a smartphone does?

Here's where Nigel Holmes' GE Super Radio remark collides with addressing DRM "power issues" to create a hypothetical pocket-sized, multimedia capable receiver. You see, I followed the Super Radio link and ended up at the first generation Super Radio manual. Here's what I noticed:

It is definitely not pocket-sized, because it takes 6 D-Cell batteries. Forget power consumption for a moment, and check how much capacity a D-Cell has: 2000 mAh on the low end for Ni-Cd.

What is the capacity of the battery in the Samsung Galaxy S3? 2100 mAh. So at worst, your humble analog radio has at least 5 smartphones worth of battery, in all likelihood 5 times that for alkaline, and it doesn't have to do all the things that a smartphone has to do like, I don't know, multimedia things.

I don't know what expectations one ought to have concerning battery life, but a digital receiver the size of a smartphone cannot hope to outlast a D-Cell powered analog radio, even if it only has one battery. An analog radio doesn't have an entire digital receive chain, or a baseband processor, or a CPU/GPU SOC, or a DAC, because it's analog.

And lastly, a bog standard MW receiver doesn't need high sensitivity. Any MW broadcaster who cares will ensure copious SNR at all times throughout their coverage area. If you think you're going to DX punctured 64-QAM, just say no to drugs.