Re: SWR
¿ªÔÆÌåÓýThe SWR/power measurements are better done off the Jackal board to keep the RF routes and the processor away from each other.? Just access to an I2C or SPI port is all that is needed. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton ¨C J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? Moderator ¨C North American QRO Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Jack Purdum via Groups.Io
Sent: Wednesday, May 9, 2018 9:24 AM To: [email protected] Subject: Re: [BITX20] SWR ? We were going to put an SWR meter on the JackAl board, but have backed away from it for this iteration. The main reason was because of the board size. The nano-acres it would take on the board would raise the PCB cost above the 100x100mm size to do it right for the possible power levels that might be involved. That doesn't mean you can't add one... ? The good news: Right now, there are about a dozen "empty" pins available on the board for experimenting. We are currently using less that 15% of the 1MB of flash memory and less than 10% of the 256K of SRAM, and that includes code space for some features that we've coded for (e.g., a RTC) but have not implemented yet (e.g, adding a button battery to power the Teeny's RTC in sleep mode). The Teensy is a 3.3V device, so we have an onboard regulators for 5V and 3.3V. Al and I think this will up the "fun level" for hackers considerably...at least that's our intention. ? The bad news: We got caught in some kind of Chinese holiday and other "delays" to get the PCB. Al ordered the board since he did all the work on the EE design. It seems our Beta PCB order got pushed to the back of the line. When I wrote to them and pointed out that I was disappointed in their service, especially after ordering more than 1000 boards from them last year, our order suddenly went from "In line" to "shipped" in less than 24 hours. I was a little more than PO'ed, but at least we got the board this week. We discovered several errors on the board (2 ours, 1 theirs), so the Beta board will have some "hairs" on it. Long story short, we will be demoing JackAl at FDIM, but not all of the features will be implemented. The order for the new board will be sent this week, and I think it will be done in a more "timely" fashion this time. We'll immediately send it to our Beta testers and then make it available via an announcement here. ? Al and I look forward to seeing some of you at FDIM! Jack, W8TEE ? ? On Wednesday, May 9, 2018, 9:49:27 AM EDT, Kees T <windy10605@...> wrote: ? ? I think Jack, W8TEE, is waiting for FDIM to tell us all the correct way to solve the problem. |
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