drmpeg

27 ms·

271.
by drmpeg 6y ago
Remember BUDs (Big Ugly Dishes) used for satellite reception? The band they operate on is 3.7 to 4.2 GHz. The FCC has repurposed 3.7 to 4.0 GHz (3.98 to 4 GHz is a guard band) for 5G. Satellite downlinks will continue to operate at 4.0 to 4
272.
by drmpeg 6y ago
There seems to be a lot of double counting in that list. For example, 44.192.0.0/11 and 44.224.0.0/11 are listed twice. Then there are 28 entries of 44.x.x.x that would fall under the two /11's already listed.
273.
by drmpeg 6y ago
Some video that was extracted. http://www.r00t.cz/Sats/Change5
274.
by drmpeg 6y ago
The slant range has a significant effect on latency. For two ground stations at the edges of the satellites footprint, each with 10 degree antenna elevation, the latency is around 540 milliseconds.
275.
by drmpeg 6y ago
It's called a gist. https://gist.github.com/
276.
by drmpeg 6y ago
Some disagreement from 18SPCS. https://twitter.com/Skitt0608/status/1316922236515848195
277.
by drmpeg 6y ago
I'm Popeye, and I approve this message.
278.
by drmpeg 6y ago
It's perfectly legal to transmit noise-like signals such as digital voice, DVB-S2 and OFDM. You just can't encrypt the content.
279.
by drmpeg 6y ago
You can read about their investments here: https://www.ampr.org/about/legal/ At the bottom of the page are the audited financial statement and tax return for 2019.
280.
by drmpeg 6y ago
The precise numbers are 4,194,304 * $26.13 = $109,597,164 - broker fee of $545,260 = $109,051,904 net.
281.
by drmpeg 6y ago
I'm a little concerned that these RV64GC implementations all end up at about 500-600 MHz. There's plenty of 1.5 GHz ARM processors at 28 nm.
282.
by drmpeg 6y ago
The popular Cypress/Infineon FX3 USB3 controller has a 200 MHz ARM926EJ core on chip. https://www.cypress.com/file/140296/download
283.
by drmpeg 6y ago
There are maintainers for each subsystem. For example, linux/drivers/media is maintained by Mauro Carvalho Chehab. When you have a patch, you submit it to the linux-media mailing list and it's vetted there. If Mauro thinks it
284.
by drmpeg 6y ago
Depends on the altitude of the residence.
285.
by drmpeg 6y ago
They're using frequencies in the 10.7 to 30.0 GHz range (GPS is much lower at 1.575 GHz) that are already allocated to satellite operations. However, they do have to share these frequencies with others. You can read all the frequency s
286.
by drmpeg 6y ago
Interesting tweet about interference and collisions between the two systems. https://twitter.com/Megaconstellati/status/12838888929120542... Link to FCC filing. https://licensing.fcc.gov/myibfs&#x2
287.
by drmpeg 6y ago
A byte addressable index register was required for 8080 assembly language compatibility to the H and L registers.
288.
by drmpeg 6y ago
Cool. Thanks for the link. I developed the code for the IEEE1394 interface on the JVC 2nd generation decks (HM-DH40000U, HM-DH5U and HM-DT100U) when I was at LSI Logic.
289.
by drmpeg 6y ago
Who remembers D-VHS? Digital video on VHS. https://en.wikipedia.org/wiki/D-VHS
290.
by drmpeg 6y ago
Unfortunately, this was around 1993-1995 and PDF's weren't in widespread use yet. Everything was on hard copy and I'm sure I tossed that years ago. It was a fully custom 32-bit ISA and we had a custom back-end for GCC (althou
291.
by drmpeg 6y ago
Die shrink of a processor I worked on in the 90's, the C-Cube CL4010. Looks like the design changed even though it was functionally equivalent. http://www.w6rz.net/IMG_0044.JPG
292.
by drmpeg 6y ago
DVB-S2 With 8PSK and 2/3 code rate would give 111 kbps at 56 kbaud. With 0.2 rolloff, the signal would be 67.2 kHz wide. The article is using FSK with a bandwidth of at least 300 kHz, so it's not legal in the US (for data only).
293.
by drmpeg 6y ago
ATSC can easily be generated with GNU Radio and any transmit capable SDR (such as the LimeSDR you mentioned). It's no worse than DVB-S as far as over the air performance. Many TV's will tune 70cm directly (cable channel 58 is 429
294.
by drmpeg 6y ago
70 cm is a bit of a problem. 97.307(f)(6) limits data transmissions to 56 kbaud and 100 kHz bandwidth. However, digital TV is allowed. Some folks have circumvented the rule by sending a low bitrate video stream as a small part of their over
295.
by drmpeg 6y ago
How about 30 Mbps with OFDM. http://www.w6rz.net/ofdm3.png
296.
by drmpeg 6y ago
I was part of this history, working for a military contractor from 1983 until 1992. From 1985 until 1990, I was project engineer for a complete rebuild of the DSP satellite system (NORAD missile warning) ground communications network. I con
297.
by drmpeg 6y ago
CONV-86 came on 8" floppy disk for the ISIS-II operating system on Intel MDS development boxes. Even if you found a copy, you'd need an MDS-80 to run it on. After the IBM PC came out, everyone tossed their MDS-80 systems when Inte
298.
by drmpeg 6y ago
I used the CONV-86 8080 to 8086 converter tool mentioned in the article on a project back in 1983. It really worked quite well, with hardly any fixup required on a fairly large (at that time) code base. I remember thinking that the 8088 (in
299.
by drmpeg 6y ago
https://www.crowdsupply.com/sifive/hifive-unleashed
300.
by drmpeg 6y ago
Comcast VOD content sent to QAM set top boxes is still MPEG-2.

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