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ChrisH
06-07-2008, 08:06 PM
Having switched to Mac I was wondering what other Mac users are using to power their notebooks? I have a Lind 12v power supply for my old PC laptop that worked great and had no RF issues with the SSB. Unfortunately Apple has a patent on the Magsafe plug that supplies power to the newer Intel notebooks and won't grant licenses to after market vendors like Lind. I'm tempted to buy a second Mac power supply just to cut and splice the 12v cord (Magsafe connector) to the Lind. The Lind puts out 20v and the Mac takes 18.5v, that may be a problem?

The fall back is to run the computer off its own battery and use an inverter to recharge the battery when the computer is off or in sleep mode. The inverter I have is 400 watts and chokes when trying to charge and run the laptop. It's also puts out a lot of RF. Going from 12VDC to 120V AC and back to 12VDC also seems like a waste of electrons.

Chris
Carroll E

jfoster
06-07-2008, 08:29 PM
http://mikegyver.com/IdeasnProducts/Kensington-Magsafe/index.html

as mentioned on

http://macsailing.net/fbb/showforum.php?fid/7/

John

BobJ
06-08-2008, 12:52 AM
Hi Chris,

John nailed it. I recently bought one of Mikegyver's 70w refurbished Kensington adapters on E-Bay. It works fine.

I had to use an inverter in '06 because they hadn't hacked the Magsafe plugs yet.

ChrisH
06-08-2008, 08:49 AM
Thanks John and Bob,

Bob, have you noticed any RFI SSB issues when using the Mikegyver adapter?

Chris

BobJ
06-08-2008, 09:31 AM
Hmm, that's a thought. I hadn't re-installed the RFI generator yet when I tested the adapter. Always something.

So how would you test for that? If it's a problem, could I just stick a choke somewhere on the adapter's cables?

ChrisH
06-08-2008, 10:15 AM
Hi Bob,
I can hear RFI coming through the SSB speaker when turning on the inverter and can see its affect when downloading weatherfax. I imagine you would hear any RFI coming through the SSB from the Mikegyver adapter when its turned on and plugged into the computer. You probably want to do a check on different frequencies between 2Mhz and 8Mhz. I'd be curious to know how it works.

During the '06 race I could hear the NMEA signal from my GPS and had to turn it off during roll call and weatherfax downloads. Despite a recent NMEA rewire with ferrite chokes the problem still exists, but now only in the 2Mhz and 4Mhz range.

Do you still have some of that Pixie dust left over from '06?

BobJ
06-08-2008, 10:28 AM
Do you still have some of that Pixie dust left over from '06?

Shhhh, that's my secret weapon!


Speaking of which, don't miss the letter and the Wanderer's response on page 74 of June's Latitude.


Okay, I'm off to the boat and I'll take the technological waffle iron, USB GPS and Kensington adapter to see how that goes.

Don't forget the meeting tomorrow night, y'all. It'll be great to see Dr. Lou - be sure to ask him what his autopilot sounds like.

BobJ
06-09-2008, 09:06 AM
The Kensington adapter messes with the SSB a bit. Not much on 4 - just a little bump when you switch on the adapter. On 6, it adds enough to the fuzz to make a weak signal harder to hear, and even more so on 8. Since I don't have weatherfaxes flowing from the SSB to the waffle iron, I can't tell you whether they would be affected.


Oh, the waffle iron thing:

Pretty similar really. You warm it up, put stuff in, push a button and close the lid. Wait a few minutes, open the lid and there you go - GRIB's on your grids! Carboloaders can add a side of grits. Got syrup?

ChrisH
06-09-2008, 11:45 PM
Thanks Bob, good info..although I'm more of a panini type of guy. I may try and cobble together something from my old Lind adapter. Still not sure about its 20VDC output harming the 18.5 VDC acceptance on the Mac battery?

ChrisH
06-10-2008, 12:09 AM
By the way Bob, looking at the mug shots on the entrants page I've noticed that your "welcome to Hanalei" elixir straw is much longer than mine. Has that got something to do with uncorrected finish time?

BobJ
06-10-2008, 10:06 AM
If you have 20v instead of 18.5, won't you get your weatherfaxes faster? Is there a PCR adjustment for that?


Instead of a mutant drinking straw, what you're seeing in the "mug shot" is the backup VHF/AIS antenna on the pushpit. Upon arrival, Lucie and Ben assessed my mental state and rightly decided I could not maneuver a straw. (While wanting to go ashore, I spent the next couple of hours fumbling around on the boat putting things away and staring off into space.)


Oh, wow - when you get to 100 posts you get to be an "Ocean Racer." Get with the posting, people!