drmpeg

20 ms·

301.
by drmpeg 6y ago
A quick check shows 360p = Baseline, 720p = Main, 1080p = High.
302.
by drmpeg 6y ago
Newer iPhones support band 42 TDD, which is 3400 to 3600 MHz. The amateur radio 9 cm band in the US is 3300 to 3500 MHz, so you could have a setup contained in single ham band. However, the open source eNodeB products typically don't s
303.
by drmpeg 6y ago
It's does a deorbit burn to actively fall back to Earth.
304.
by drmpeg 6y ago
Wide band antennas like this PCB Vivaldi slot are popular with the SDR crowd. http://www.w6rz.net/IMG_0069.JPG https://www.amazon.com/RFSPACE-Wideband-Antenna-600-6000-Viv...
305.
by drmpeg 6y ago
318 dB for Voyager 1 at X-band.
306.
by drmpeg 6y ago
For me, listening to music is just another distraction.
307.
by drmpeg 6y ago
In the US, the current licensed 5G millimeter bands are 24, 28, 37, 39 and 47 GHz. 60 GHz is an unlicensed band (actually 57 to 71 GHz) used for 802.11ad. Typical use is uncompressed HDMI extenders inside of a single room.
308.
by drmpeg 6y ago
Most likely a TV station. Known as "Franken-FM stations". https://en.wikipedia.org/wiki/Channel_6_radio_stations_in_th...
309.
by drmpeg 6y ago
It's funny that nobody has ever changed the frequency units from Mc/s to MHz. https://www.law.cornell.edu/cfr/text/47/73.201
310.
by drmpeg 6y ago
All the channel numbers are used. But in the analog days, channels were separated by market to reduce interference. One market would use 2, 4, 5 and 7 while the adjacent market would use 3, 6 and 8.
311.
by drmpeg 6y ago
The term you're looking for is "call sign". K and W have been assigned to the United States. https://en.wikipedia.org/wiki/ITU_prefix
312.
by drmpeg 6y ago
FM stations broadcasting HD Radio are 400 kHz wide. http://www.w6rz.net/fmbandzoom.png
313.
by drmpeg 7y ago
we had own gcc backend Brings me back to 1995 when I was working on the C-Cube CL4010 MPEG-2 encoder processor. A fully custom 32-bit (with some 36-bit registers) RISC architecture. http://www.w6rz.net/cl4010.png
314.
by drmpeg 7y ago
Yet a fairly large portion of ham radio activity is now digital (FT8).
315.
by drmpeg 7y ago
If it was low-band (30 to 50 MHz) police radio, it was most likely sporadic E propagation.
316.
by drmpeg 7y ago
Although this is a wonderful accomplishment, it should be noted that tropospheric ducting happens every summer between the west coast of the US and Hawaii (at approximately the same distance of ~3800 km). The highest frequency contact was o
317.
by drmpeg 7y ago
The indicated FT8 signal to noise ratio is very misleading. The calculation is based on a noise bandwidth of 2500 Hz, yet the FT8 signal is only 50 Hz. The actual minimum signal to noise ratio of FT8 is around 1 dB in 50 Hz (-156 dBm in a g
318.
by drmpeg 7y ago
They're horrible. The 3rd harmonic is just a few dB down.
319.
by drmpeg 7y ago
Or direct sampling. Although they're expensive, there are 10 Gsps ADC's these days. https://www.analog.com/en/products/ad9213.html
320.
by drmpeg 7y ago
Many cable channels are using DVB-S2 8PSK at 5/6 rate. That would be 110 Mbps in 54 MHz (45 Msyms/s).
321.
by drmpeg 7y ago
Spacex could be in trouble too. http://tmfassociates.com/blog/2020/03/21/why-spacex-desperat...
322.
by drmpeg 7y ago
Even satellites built in 1967 were digital. https://destevez.net/2020/03/decoding-les-5/
323.
by drmpeg 7y ago
One of my first engineering jobs in the late 70's was working at a paper dryer manufacturer in southern Maine. The owner's son had a little side company the was building process control systems for the dryers with Multibus based c
324.
by drmpeg 7y ago
I've done ten channels of broadcast FM with GNU Radio. The limiting factor is processing power. Here's a spectrum with all channels sending the same audio. http://www.w6rz.net/fm10.png
325.
by drmpeg 7y ago
It's in bionic updates. https://packages.ubuntu.com/bionic-updates/firefox http://ports.ubuntu.com/pool/main/f/firefox/firefox_73.0.1+b...
326.
by drmpeg 7y ago
I'm running Firefox 73 on my BeagleBoard-X15 (Cortex-A15). Ubuntu 18.04. $ dpkg -l | grep firefox ii firefox 73.0.1+build1-0ubuntu0.18.04.1 armhf Safe and easy web browser from Mozilla
327.
by drmpeg 7y ago
There's an old saying in the amateur radio hobby. If you want to make a small fortune in ham radio, start out with a large fortune.
328.
by drmpeg 7y ago
Back in 2009, I made a super high bitrate (70 Mbps) version of Big Buck Bunny. It was super popular with the Network Attached Storage crowd. Here's a segment. http://www.w6rz.net/bbb24p_00.ts
329.
by drmpeg 7y ago
Before I retired, I avoided getting a cell phone because of this. Where I was working, I could see that my co-workers were using their cell phones as a company intercom. I didn't want any part of that.
330.
by drmpeg 7y ago
Same here. I like to say "Don't tell anybody".

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