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DSSS remains the low rate modes for 802.11 chip sets at 1 and 2 Mbps operation.? ? It might be good to review the issues around using DSSS in 802.11, as this is very well understood in terms of

Primary focus is the HF ham bands. However, I've also studied the part 15 rules rather closely. My goal is reliable, long distance, peer to peer communications of short messages at very low power

Hi Reg – Yes – also the data rate will be of great consequence when you consider the effects you mention, as well as the accuracy of the timing source. For real high data rates even a good

Mike, Yes, GPS time is key. You've also got to determine the propagation and multipath delays so they can be summed properly. You *can* synchronize by using a special PRN. With a 0.5 ppm TCXO you

I want to hear more as your work progresses. I too have been thinking about something like this. What band do you plan to use? I assume you're in the ham bands. Steve Hendrix

Reg, Thanks. I won’t even pretend to say that I understand how to do this but it’s something I’d like to dive into someday. -Craig Sent: Tuesday, November 03, 2020 2:35 PM To:

Craig, Yes, that's the idea. The crosscorrelation is an FFT and multiply by the PRNs of the selected senders. This makes it very computationally cheap to monitor several senders in a net and ignore

It seems they would not only have to have the same seed, or key, but also the same timing. 73 - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115

Reg, Fascinating! I've wanted to play with this for many years also. Quick question that I've never understood about PRN's. Does everyone (ham community) use the same formula for generating PRNs

Hello Reg and the group Glad you like your new toys. I am sure your endeavors will keep you busy for the winter. The RFzero are assembled by an EMS so the quality is fully pro:

This is a simplified outline of a digital mode I have wanted to test for almost 40 years. It's a direct application of the basic theory of probability and random processes. I later learned it had

My RFzero boards and accessories arrived yesterday. Quality is excellent. I've not powered anything up yet as I am still collecting documentation. After more thought, my plan is to connect an

David, Wow! Thanks a lot for that link! That is absolutely perfect for my project. And a very nice suite of other boards for filters, etc. I'm getting a pair so I can do short range tests with a

Reg, An easy to use and fairly inexpensive RF source is the RFzero https://www.rfzero.net/ about $64 + shipping, designed by Bo, OZ2M.? Frequency range 2289 Hz to 200+ MHz, with frequency resolution

FYI I had asked a few days ago about getting QEX as the membership print option. Much to my delight I received the following today from Becky Schoenfeld: " Our Membership Department has advised me

I've got a considerable pile of WW II RF stuff Dad bought on Radio Row (Cortlandt St, torn down to build the World Trade Center) in NYC after the war. I don't recall ever seeing a silver plated coil

Hi! I understand VHF / UHF coils are silver plated, not because silver has a slightly lower resistivity than copper, but more because silver oxide is conductive, whereas copper oxide not. This

I'm mostly a lurker on several test equipment groups, enjoy the learning and the insights from the "old heads" who designed the great test equipment in the early days of electronics when it was mostly

Steve J. Noll, WA6EJO. Mostly retired optoelectronics test engineer. Active HF through microwaves. Also ATV, machining, optics, test equipment, VHF and above contesting.