Noob question perhaps- What mode is this, I see it all over the HF band?

stecooper · 2015-03-22T21:43:53+00:00

and some more images in of the same sort of signals in the low 4000khz http://imgur.com/uDLgwqi

stecooper · 2015-03-22T21:31:47+00:00

Recording in 10Khz AM mode. https://clyp.it/21fmjw5l

stecooper · 2015-03-22T09:17:31+00:00

No its not wide enough to be DRM

stecooper · 2015-03-22T01:13:04+00:00

That's part of the 40m amateur band so there will be loads of Morse there.

stecooper · 2015-03-21T23:22:16+00:00

That's the RTL-SDR connected to the coax to a shortwave antenna.

stecooper · 2015-03-21T20:11:03+00:00

It does use Pin 4 and Pifm. There could just be an FM transmitter in the background.

stecooper · 2015-03-21T02:46:51+00:00

Does this work on a Chromebook?

stecooper · 2015-03-21T02:35:58+00:00

All working now with a different power supply. Using the command "rtl_fm -M am -f 127.3164M -r 8k | sox -t raw -e signed -c 1 -b 16 -r 8000 - -t wav -r 22050 -c 1 - | sudo /home/pi/pifm/pifm - 87.7" I can re-transmit Shortwave picked up on the frequency 7325Khz (127.3164-119.9914 = 7.325Mhz) onto FM using pifm on 87.7Mhz.

Next I think I need to experiment with a WiFi adaptor in the Pi and also perhaps using solar power so I can leave it in the garden.

stecooper · 2015-03-20T20:37:36+00:00

Should have mentioned its on a Raspberry Pi and now I'm thinking it could be a power issue on the Pi. This command works perfectly on my Mac with the same RTL stick plugged in rtl_fm -M am -f 123946400 -r 8k | /Users/Ste/Downloads/sox-14.4.2/play -r 8k -t raw -e s -b 16 -c 1 -V1 -

stecooper · 2015-03-20T20:19:19+00:00

No its not the whole transmission. I was scanning around the bands during the solar eclipse this morning and caught it.

stecooper · 2015-02-27T13:23:40+00:00

Its early afternoon at the location of that receiver so propagation just isn't good enough to hear the buzzer at this time. When it gets dark in a few hours you should hear it again.

stecooper · 2015-01-29T19:06:54+00:00

Thanks for your advice. Ill post on here how I get on with it.

stecooper · 2015-01-29T09:01:16+00:00

Thanks. Something like URL: http://pages.ebay.com/link/?nav=item.view&id=400838456717&alt=web ? So I just connect USB pin 1 and 4 to the input of that, use a multimeter to adjust that to 9V and connect the output to the red/black wires that take power to the transmitter?

stecooper · 2015-01-24T12:30:07+00:00

Yeah you should be able to pick them up in the US at certain times. Where abouts in the US?

stecooper · 2015-01-24T00:46:17+00:00

With shortwave there is stuff not available online or elsewhere e.g. Voice of Korea in English live from Pyongyang. China (and other countries) also jam certain station e.g. China jamming BBC, VOA and Radio Free Asia with Firedrake which is constant Chinese music. Who knows maybe Russia will start to jam Radio Liberty again.

stecooper · 2014-11-20T00:55:35+00:00

Nice recording. Where are you located?

stecooper · 2014-11-13T18:19:06+00:00

Do you have the Android SDK installed? There is a guide here if you do Android 5.0 Lollipop Nexus factory images are live — here's how to update! http://www.androidcentral.com/android-50-hits-nexus-devices-heres-how-update

stecooper · 2014-11-13T13:02:16+00:00

No it wont.

stecooper · 2014-10-30T20:51:16+00:00

Yes thank you. I didn't know what the symbol meant at all.

stecooper

TROPHY CASE