Dear Internet of Things: human beings are not things

[shaddack]

@gregmcph

And that’s the scare tactics. The truth is it hasn’t happened. Your unpleasant tendency hasn’t happened.

Snowden would disagree.

Then there are other companies like Ashley Madison that get their databases compromised.

My unpleasant tendency keeps happening over and over and over.

[anon8420928]

@shaddack

Such data have that unpleasant tendency to leak

@gregmcph

And that’s the scare tactics. The truth is it hasn’t happened.

My friend Google disagrees with you.

[dobby]

@shaddack

Consider it a prototype, or a pre-prototype. A good beginning with warts. SDR implementation will eat batteries, though; a dedicated hardware may be better here. Perhaps a “real” pager with an Arduino chip for interface.

I belive an RS-232 interface is possible off the decoder from the old 90s type Motorola Bravo pagers on the way to the LCD. Ironically living in a mountainous area I have no pager signal RX so I have limited ability to experiment unless I also slap together a QRP paging tx system.

[shaddack]

@dobby

I belive an RS-232 interface is possible off the decoder from the old 90s type Motorola Bravo pagers on the way to the LCD. Ironically living in a mountainous area I have no pager signal RX so I have limited ability to experiment unless I also slap together a QRP paging tx system.

If you had better signal (or if you can rig up a SDR transmitter) you can poke around the receiver with a scope and look for the raw bitstream. Then decode it with an arduino.

[dobby]

@shaddack

Then decode it with an arduino.

So much computing power for a serial or even decoding a 2400baud 900mhz, 160mhz, or FM broadcast signal, a musical birthday card has more computing power than required for the purpose and burns less battery. I remember my Moto-Bravo pager lasting a month on a AA battery, the secondary decoding and feed to phone should budget way less than the RX.

[shaddack]

You can get the ATmega chips quite low on power consumption with judicious use of sleeping and interrupts and clock frequencies.

Always keep a surplus of computing power (and memory and flash…). You never know when another feature will be handy.

[dobby]

@shaddack

(or if you can rig up a SDR transmitter)

As we veer off topic completely(it is an effing hacker thread) have you seen a cheap SDR encoder/VFO? I would love a TX companion to the hacked DVB-T USB dongles. I have been wanting to build a nice waterproof air band/EPIRB survival radio to carry when flying(trying to get into the Canada-Greenland-Iceland-Scottland airplane ferry service) to replace the personal ACR sat-beacon and Icom radio I schlep now. Blue sky it would have a marine and 7700 encoded ATC radar transponder, air band AM voice, marine VHF voice/GMDSS, 121.5 audio homing beacon, and programmable 406mhz SAR-Sat channel w/GPS, GPS nav, and emergency VOR, DME, and lacalizer/glideslope. A freaking in and out of cockpit emergency radio Swiss army knife, hell why not add an LED strobe to the kludge, though with a good fast sampling SDR hopping around between freqs and having a good selection of use modes not so much kludge as it is all in software, and AT-Mega would be perfect for this application.

[shaddack]

@dobby

have you seen a cheap SDR encoder/VFO?

The software should be available for free, though some assembly may be required. Or C, more likely. I am poking around the receiving end, so far.

For the hardware, here’s some selection.

List of software-defined radios

[dobby]

@shaddack

For the hardware, here’s some selection.

As far as I can tell these are all RX-only.
There is the softrock but(and I know it is super tricky to do an ultra wide coverage clean TX) I would love to be able to tune and encode the way the DAB-T dongles decode and tune, the rest is making a cascade of band passed filters to kill weird harmonics and out of band stuff flowing to the amp. It also gets tricky once you get into the higher UHF freqs because the RF goes everywhere except where you want it.

[fuzzyfungus]

Ettus’ USRP series definitely does TX(they may have some more fully integrated products now; but historically you’d choose the daughterboard(s) necessary to suit your target frequency ranges).

Those tend to be on the pricey-serious side by the standards of the genre; but are well supported by GNU Radio(they were pretty much the SDR that GNU Radio targeted, back before the proliferation of relatively cheap, but mostly RX only, devices based on assorted repurposed silicon.)

Unfortunately, though, wanting to transmit will usually drive up the price, sometimes considerably. It can also mean switching cultural groups(there is obviously some overlap; but less than one might expect) between software-people-who-discovered-that-they-can-now-get-RF-signals-to-process and HAM enthusiasts who have been transmitting since before you kids and your fancy transistors existed; and have gradually adopted various new techniques in radio gear.

Sort of like the jump between the 3d-printer universe and the descendants, hobbyist and professional, of machine shop technique. It’s not as though the two populations are totally disjoint or anything; but there can be a substantial disconnect.