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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  


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About valis

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    Friday Harbor, WA

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  1. Summer cruising San Juan Islands

    For forested islands, it can be as easy as anchoring off of Jakle's Lagoon on San Juan Island, rowing ashore, and hiking through the woods up to Mt. Finlayson (not particularly tall) to see the eagles and watch the sunset over Vancouver Island and the Strait of Juan de Fuca. Not a bad place to spend the night.
  2. Falcon Heavy....just amazing.

    We're sorry you're a dick, too. How about you come back when you've accomplished something 0.00001% as challenging as what those SpaceX people did.
  3. E-nav on the cheap

    The specs sound fine, and if it actually meets them it should run cool and easy with the Minix system load. Have I mentioned EMI? Computers and switching supplies can generate quite a bit. I haven't evaluated the Minix on that score, but I suspect that it's pretty quiet. You should check your radio reception and possibly lay in a supply of ferrites to keep the cables from radiating noise. HF/SSB problems are more likely than VHF/AIS interference. I may have already mentioned this somewhere, but I did a presentation for the Singlehanded Transpac group about radio operation and it's got some decent EMI and ferrite advice on page 14: http://www.sailvalis.com/presentations/SHTP Communications 2012.pdf
  4. Falcon Heavy....just amazing.

    You're an asshole fuck. That WAS reality for those SpaceX personnel. They made that happen. I clapped too, just admiring their success. Good for them!
  5. Sailing Books for Children

    +1 for Scuppers the Sailor Dog! My grandson loved this one when he was three or so (we read it to him), and now whenever we find or build a driftwood shack on the beach we all call it the "Sailor Dog house". Another read-aloud one is "The Maggie B". Our daughter liked it so much when she was little that decades later we named our little psuedo-tug "Maggie E". "Where the Wild Things Are" has a little bit of sailing in it. None of these are about sailing, exactly, but have boats as an element.
  6. E-nav on the cheap

    Yeah, I've seen that "direct sample" the lower frequencies stuff, but don't understand the architecture well enough to know how well it's going to work. There will be aliasing of signals above and below 14.4 MHz (it uses a 28.8 MHz sample rate), and that SDR has no useful filtering. There may also be aliasing of signals above 28.8 MHz, although there aren't many of those at sea. This means the background atmospheric noise will be worse and there will possibly be interference to the desired signal from these spurious responses. But away from land you won't have a lot of strong local signals, so it might work well enough. One thing I really like about SDRs is that you don't have to fight the audio-connection ground loops and power supply noise that you often have with an analog audio connection. The 8-bit quantization will also reduce performance (compared to a 12 or 14-bit chip) but probably not horribly so. You can add an external filter to clean up much of this spurious response problem, but you might as well spend that money on a more capable SDR. I agree completely! It's like my RPi WSPR transmitter, generating a 14 MHz narrow-band 4-FSK signal by wiggling a digital output pin. The fact that it works at all still astounds me.
  7. E-nav on the cheap

    How do you handle the screen brightness? My old Lenovo USB monitor couldn't be software-controlled (AFAIK), and the brightness control was on the back of the panel so access would be a problem. Of course I could always put a hole in the backboard for access. And even at minimum brightness it was still brighter than I like for nighttime use.
  8. E-nav on the cheap

    Is that built from HDPE stock? Some of the bits look too shiny for that.
  9. E-nav on the cheap

    Please tell me abut that cassette. I've used velcro, duct tape and bungee cords to hold my USB display, and would really like a good RAM arm solution.
  10. E-nav on the cheap

    Ajax, kent_island_sailor is right. The computer (or any load) takes the amount of current it needs from the power supply (or battery). Within reason, I would rather have a regulator that is capable of more current rather than less. Way too much margin leads to high standby power drain, but a little margin is a good thing. The cheap $20 SDRs were originally designed for digital television reception, and only cover the (roughly) 50MHz - 1GHz region. This can be used for AIS reception and decoding, but not for HF (3-30 MHz) weatherfax. There is a $100 and up class of SDRs that have a much more flexible front-end (filters, mixers, amplifiers, etc) and more stable oscillators, and these usually cover 100kHz - 2GHz or so. These are the ones we can use for WFAX. I've tried "SDRplay", and "Funcube Dongle Pro +" wideband SDRs and they work pretty well. None of these relatively inexpensive SDRs will have the dynamic range or interference rejection of a quality radio receiver / transceiver, but on a boat at sea we are less likely to experience strong local interference. Here's an example of what the "SDRplay RSP1A" receiver can do. I've got one running in Friday Harbor, connected to a dipole antenna and continuously monitoring the 20-meter ham band on the "FT8" digital frequency. Over a 24-hour period I received all these stations: p I especially like the one in Svalbard! I just checked and yesterday I also picked up Bear Island (halfway between Norway and Svalbard).
  11. E-nav on the cheap

    Are you signed up for the 2018 Pac Cup? The Glomex splitter looks good, if it does what it claims. I would ask around. If you're doing the Pac Cup, you need a spare VHF antenna (for when your mast falls down), so instead of the splitter you might mount the spare antenna to the pushpit rail or something. The range won't be as good as a masthead or spreader-mount antenna, but it's certainly good enough. Just don't try actually using one of those "emergency VHF antennas" (with the suction cup). It works, barely, but about as well as a straightened-out paper clip. I like SDRs, but I've only played with the more expensive DC-daylight ones, not the VHF only type. Do your testing. That BNC/SMA adaptor is fine, as long as you have everything strain-relieved. When you stack an adaptor on the SMA connector you can put a lot of leverage on the SDR dongle, possibly damaging the SMA and/or USB connector-to-circuit board interface. I've done it, and had to crack open the SDR plastic case and do some very fine soldering. That 12V supply -- I can't find input voltage range or output current specs. It could be fine, but do your testing or find one that has appropriate specs. Power barrel connectors!!! Why can't they standardize on two or three, rather than the dozens of variants??? It's not like they are really preventing you from plugging in a wrong voltage plug, since I've seen 5V and 12V systems use the exact same plug. Oh well, I have a couple boxes full of old wall-warts, and I can usually find the right ones to make a Frankenstein's Monster or just a cable. OCPN will do WEFAX from a sound card interface, but Win10 has changed the way some of the soundcard stuff works. You may need to do some configuration changes or install some soundcard drivers / splitters / etc. I got this to work (with SDRs) on two different Win10 computers, and one Win7 computer, and the details were different for each of them. With your Sony radio and an audio interface, you might have to fight with signal levels, ground loops and hum, so be prepared. Keep us posted!
  12. E-nav on the cheap

    Ish, are you sure it isn't a case voltage drop from corroded connections? 14V starting voltage sucks big-time. My Espar starts fine at 12.x V.
  13. E-nav on the cheap

    Those look nice, and the "isolated buck-boost" one has a great input voltage range of 10 - 30V. But it's way more power than needed for the Minix system, and costs damn near what the computer itself costs. It is sort of amusing that the tiny computers we are using (Minix, Raspberry Pi, etc) have become the least-expensive part of the system. The company I was thinking of is "Lind Electronics". Here is an adaptor of theirs that might be appropriate: https://lindelectronics.com/product/vb1285-1169/ It costs $50. The input range is only 11-16 volts, but that's probably fine. Of course the Minix itself can likely handle that range, but getting a guarantee of that is unlikely. I don't know if Lind is really any better than the cheaper stuff, but they were recommended and mine has worked well. My battery bank is big and pretty stable, so I'm not stressing things very much.
  14. E-nav on the cheap

    I don't think the DROK unit does what you want. It appears to be an adjustable buck converter, and they say "the input should be at least 3V higher than output". You need a boost/buck. There is one brand that is well-regarded, and it works for me. Unfortunately I can't remember the name, but let me work on that (gotta run now, coming back tonight). FWIW, I ran my MINIX up to 15V and there wasn't any smoke...