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2020/05/22 45 mile loop to Alviso, Don Edwards Wildlife Refuge, and Back via the Green Belt
π 2020-05-22 01:01 in Exercising
A mere 13 years ago, when we still lived in Sunnyvale, we did the shorter bike ride to Alviso. The ride was 24 miles then.
It was time to go back, but now that we live farther, and that I extended the loop, it was 45 miles this time (the whole loop was about 7H of clock time and 5h of actual biking time, or longest for us this far). (click on the garmin recording for more stats and a bigger map)

nice pink house on the way to Steven Creek Trail
nice pink house on the way to Steven Creek Trail

lovely tree
lovely tree


Norcal radar site
Norcal radar site




babies are grown up already
babies are grown up already

so proud
so proud



Eventually we got to Alviso, the land that time forgot:




prime real estate in a flood zone, awaits for you
prime real estate in a flood zone, awaits for you



interesting house
interesting house

it was a mixed neighborhood
it was a mixed neighborhood


Jennifer still found fruit :)
Jennifer still found fruit :)

From there, we got to the Alviso Don Edwards loop (we did the longer double loop):


for once, a train that almost looked fast
for once, a train that almost looked fast






salt from evaporation
salt from evaporation










After the long loop, it was time to bike all the way home (almost 2H), back around great america, 49ers stadium, and greenbelt back to Stevens Creek Trail:




This was our longest bike ride ever, it went well considering. Maybe 50 miles next time? :)

2020/05/15 Skyline to the Castle Rock Park
π 2020-05-15 01:01 in Hiking
Many years back, Jennifer and I did Skyline to the Sea, starting at Castle Rock. Back then I didn't know about Castle Rock, we walked maybe 15mn from it, but missed it, and we also missed Goat Rock, and I had no idea.

So, I called it Skyline to the Castle Rock as we started with Skyline to the Sea backwards and finished at Castle Rock: Here is the garmin connect page:



Although here's a much nicer map, showing the previous Skyline to the Sea hike we did compared to this days's hike:

Planning the hike was a bit interesting because the CA Governor was nice enough to close all state parks, but in a way that someone could mistakenly enter them from another location and realize when exiting that the reason they didn't see anyone at all on the trail (and why it was actually so safe), was that other people were kept away.

nice parking spot next to the trail entrance
nice parking spot next to the trail entrance

oh, not this way
oh, not this way

this way ok?
this way ok?

I can see the tow truck saying 'fuck it, I'm not getting paid enough for this one'
I can see the tow truck saying 'fuck it, I'm not getting paid enough for this one'






castle rock trail camp now reservable, how nice!
castle rock trail camp now reservable, how nice!



beatles were out having orgy sex
beatles were out having orgy sex


we found out that the lizards get ticks and their blood kills the lyme bacteria in them
we found out that the lizards get ticks and their blood kills the lyme bacteria in them




turkey vultures
turkey vultures


Great that we got to see Castle Rock this time:




fun without the crowds
fun without the crowds



Then we got back to skyline. Ooops, you mean we weren't supposed to be here:



Across the street, Indian Rock and other trails not part of the CA park, were open:




The 3.3 mile hike back to the car looked ok, but was very close to skyline and car noise:


lookout tower, and old observation site, now overgrown
lookout tower, and old observation site, now overgrown


slight renovations required
slight renovations required


by then, we were getting tired, 15 miles and 7h of hiking already, and we made it back to the car after 7.5h
by then, we were getting tired, 15 miles and 7h of hiking already, and we made it back to the car after 7.5h

See more images for Skyline to the Castle Rock Park
2020/05/07 Backyard 'Wildlife'
π 2020-05-07 00:00 in Public
Ok, it's not "real" wildlife, but it's still fun to see a few animals in your backyard.

Then, we have little lizards everywhere (well, big and small). The small ones are easy to catch :)


grippy claws :)
grippy claws :)


We've also heard racoons at night, and I was able to snap a couple of pictures. Thankfully they don't seem too bold and too much of a pest like we've heard they can be:




Howeer, what we have quite a bit is lovely possums, we mistakenly caught a few and of course released them:




such a cutie
such a cutie

it wasn't too scared to eat
it wasn't too scared to eat



we got another one the next day, or was it the same?
we got another one the next day, or was it the same?

Ah, but the subject of pests brings us to gophers. Those fuckers have been making swiss cheese out of our lawn. Since repellents don't help, I've been using smokers in their tunnels, and poisnned worms they're supposed to eat. That seems to have helped with the problem, but I think we still have a couple left.


We even ended up with a skunk, oopos:


it was tricky to get out without being sprayed
it was tricky to get out without being sprayed

We also have the occasional rabbit:



And rats:


See more images for Backyard 'Wildlife'
2020/05/06 Good Entertainment from our Bird Feeders, and Stupid Squirrels (2020 update)
π 2020-05-06 00:00 in Public
A while ago, I bought a bird feeder because I thought it would be fun in our yard, and sure enough, it was an instant hit. We got to see many interesting bird, including a baby woodpecker probably related to the big woodpecker that's living in our of our trees and making swiss cheese out of it :)

I have many pictures of those birds, but these are hopefully the best:











a junko was feeding the wrong bird, oops
a junko was feeding the wrong bird, oops


that was a lot of doves
that was a lot of doves










After a while, built aa new mostly squirrel proof bird feeder:






We also got beautiful woodpeckers: [rigimg:1024:501*|]



We also got a few wounded birds:




And we also got a few hummingbirds. Those are cool:



Squirrels started by being cute before the bird feeder:




The only problem were the squirrels that started by eating fallen seeds, but eventually went to the source:

they look good when they start
they look good when they start

clean the seeds by your doorstep
clean the seeds by your doorstep

then they climb
then they climb

and climb
and climb

and jump
and jump

and climb
and climb

and jump
and jump

The squirrels really became a problem, so I had to trap them and get rid of them:

I tried to build a defense, but it was pointless
I tried to build a defense, but it was pointless

on the plus side, I could capture all the grain the birds were dropping
on the plus side, I could capture all the grain the birds were dropping

so I had to bait them with peanut butter
so I had to bait them with peanut butter

2020/05/04 Hacking Power Supplies and Battery Pack To Get Around ThinkPad P73 Broken Power Supply Design
π 2020-05-04 01:01 in Electronics, Linux
While I wrote this for my Lenovo Thinkpad P73, this is likely equivally relevant to P53, P72, and P52.

Thinkpad P73 vs P70, not a win all around: only one 2.5" drive instead of 2, and a badly deesigned power system

So, when lenovo came out with the Thinkpad P70, I wasn't very happy because if you had a 90W power supply, it refused to charge from it, at any rate whatsoever. I was not impressed, but eh, at least it would still power the laptop so that its batteries didn't go flat while plugged in.
Well, leave it to lenovo engineers to make things worse the for the P73. The minimum power supply was raised from 135W (170W recommended) to 170W (230W recommended) which is understandable, but lenovo decided to ensure that the laptop will not take any power from any power supply that does not identify itself as 170W or more. This means that even ifit only needs 40W to sustain itself without digging into the batteries, it will completely refuse to use a 90W or even 135W power supply for anything at all, and kill the battery instead. Lenovo, you just plain suck, there is no excuse for this.

P70 vs P73, they look pretty similar
P70 vs P73, they look pretty similar

*Update*: it seems if that if you get a cheaper nvidia chip with the P73, it is then configured to accept 135W power supplies as the minimum required. That said, it will still refuse to work with any regular 90W power supply or external battery back, unless you force it with the center pin resistor swap.

While I have no plans to use windows on that machine, I thought I'd just try it out to see how it does on power. This is where I was impressed, windows can idle at less than 10W for more than 11H runtime, while I'm lucky if I can get linux at 15W. This is definitely a place where linux should do better, of course, it's not as if Lenovo put any work into making linux more efficient on their hardware either:


*Update* : with tlp and using the nouveau driver just enough to turn off the nvidia chip, I'm now able to tune the laptop down to 10W, almost matching windows.
See tlp issue 494 for details on how to setup tlp to run in low power mode when power is plugged in.

Another disappointment is that the P73 is mostly the same size and weight than the P70, but it has less room for storage. It has a bunch of empty spaces that aren't used for anything, and it can't use two 2.5" SATA drives anymore, like the P70 could. Worse, the now single 2.5" slot uses a lenovo only ribbon cable that does not ship with the laptop and basically means you cannot even add a 2.5" drive without that special ribbon cable, which isn't in stock yet. Well done... Ah yes, the battery is also not hot swappable, even if it is replaceable (unlike a Mac laptop where everything is sealed shut).


this shows the unobtanium lenovo cable for the now only single drive that fits, along the unused space
this shows the unobtanium lenovo cable for the now only single drive that fits, along the unused space

Ok, stop complaining, just buy a bunch of 170w or 230W power supplies and move on with your life

Well, yes and no:
  • I literally have 10 power supplies between home and work, not really looking at replacing all 10. Lenovo wants $137 per power supply by the way, even if they are $85 from other sellers
  • those 170W/230W power supplies are huge. They also weigh as much as some small notebooks (!)
  • I have 12V to 20V car adapters, those won't work anymore
  • I have external battery packs for extended runtime, and I haven't found a single one that can deliver the amps a P73 tries to needlessly require
  • Tricking the P70 and P73 into accepting a power supply it wouldn't otherwise use

    Lenovo uses the a center pin resistor to know how much power they can draw from the power supply, see: http://www.thinkwiki.org/wiki/Power_Connector .

    For the P70, I built this power supply adapter with a resistor bridge to tell the laptop how big it should think the power supply, is:


    It's basically a configurable version of this. Yes, lenovo, I thank you for the hours I wasted opening up power supply plugs and replacing the center pin resistors:


    Here's how the P73 responds:

    - 230W works fine   4.6k
    - 170W works ok     1.9k (1.8k also ok)
    - 130W rejected     1k
    - 90W  rejected     550 

    The rejected power supplies will be used to charge the laptop if it is shutdown, but they will not be used in any way otherwise. On the P70 the laptop would at least use the power supply to keep the laptop alive, and use half battery half external power supply. Not so with the P73, it just ignores it entirely.
    This is utter bullshit as I have plenty of 90W power supplies, including 12V car converters, or a 90W external 20V battery pack I can't use anymore.

    You can go read my Hacking a thinkpad slim tip adapter to output more than 90W (required to charge a Thinkpad P70) page for details, including this nice battery pack I couldn't use anymore:


    *Update* : so, actually with some serious tlp hacking (basically I told it to force battery mode even if a power supply is plugged in), I've managed to throttle the laptop enough, even when plugged in, so that it only uses 20W. At that point, I'm actually able to use my old external battery pack, as well as a 90W power supply, as long as I lie to the laptop and pretend they are 230W power supplies with the resistor trick. In my tests with windows, it was not possible to throttle the laptop enough when plugged in, not to have it overwhelm a smaller power supply (not that 90W is small for a laptop that normally uses 20-30W when it's not charging batteries).
    If you scroll to the bottom of the page, you'll also see a terrible buffer lipo hardware hack I did that allows to use the battery pack with higher amp draws, but it's a bit ridiculous (and bulky).
    See tlp issue 494 for details on how to setup tlp to run in low power mode when power is plugged in.

    Without the tlp hack or the buffer lipo hack, when I lie to the laptop and tell it is connected to a a bigger power supply, manage power draw with what I run, and disable battery charging in software, but the laptop will still draw the power supply for over 100W when you plug it in for a fraction of a second, and refuse it if the voltage drops.
    Obviously this would not be a problem if the laptop simply had a 90W power supply mode where it throttle things down and turned off battery charging. This is mostly what the P70 does.

    In the meantme, on top of hacking my power supplies, I also made this for my laptop, it looks silly and makes the thinkpad not look like a professional laptop, but well, that's lenovo's fault:


    this takes any power supply and replaces the center tip resistor with a 1.9k one to emulate a 170W power supply
    this takes any power supply and replaces the center tip resistor with a 1.9k one to emulate a 170W power supply

    From talking to Lenovo, they don't think that this is really a problem, so since I'm an engineer, I made my own external battery pack, but I otherwise recommend to road warriors to avoid thinkpads from now on, given the backward power design in this one.

    Making a Thinkpad P73 compatible external battery pack

    I did some testing and confirmed that the laptop is very picky about power supplies. It even rejects a 19.7V 20A power supply I had, because it's 19.8V and not 20V. Same thing for amps, it needs to be able to draw maybe around 5A for a short time to accept the power supply (they sure are putting a lot of effort into making sure the power supply is not under-spec'ed).

    Prototype with 150W step up converter which takes my 16V lipo to 20V while delivering enough amps to make the laptop happy:


    it works, and the laptop thinks it's connected to a 230W power supply thanks to the center pin resistor.
    it works, and the laptop thinks it's connected to a 230W power supply thanks to the center pin resistor.

    Here's a quick demo:

    Version 2 was to have a way to recharge the battery pack while it's being used. I've used this to use the battery pack as a buffer to absorb peaks from the laptop without tripping an external power supply, including in a car limited to 100W or a plane power supply limited to even less:

    this works in theory, but the lipo charger is quite slow and wouldn't keep up for long, but I made a better version shown lower down
    this works in theory, but the lipo charger is quite slow and wouldn't keep up for long, but I made a better version shown lower down

    Lenovo's P73 airplane mode simply stops using the external power supply and reverts to batteries. Sigh...

    Oh yes, let's talk about airplane mode. The lenovo engineers thought of everything: if they detect that the power supply drops a few times in a row, they offer a nice setting which is supposed to make the plane more airplane friendly. How friendly you ask? Well, you could throttle down the CPUs, disable battery charging, do smart stuff like that. Or, if you're lenovo, you can have airplane mode simply refuse to use the power supply altogether. Thank you lenovo, you wrote a feature that saves me the trouble of unplugging an otherwise perfectly good power supply that you refuse to use (to be super clear, my 230W power supply is plugged in and airplane mode just disabled it):


    Making a battery pack to act both as buffer for a smaller power supply, and as emergency external power (even power the laptop from 12v)

    Anyway, back to the battery pack, I found the ISDT H605 Air lipo charger which is small enough and can charge the lipo at 5A, which should be enough to keep up with the laptop when not doing CPU crazy stuff. This also allows using a 12V power supply or a lower wattage lenovo power supply to recharge the pack while it's in use, or not:


    version 1 was a bit bigger than I wanted, 90W power supply shown for scale
    version 1 was a bit bigger than I wanted, 90W power supply shown for scale

    here, the 90W power supply is recharging the battery at 2.5A while it's being discharged at 3A on the output side, using the battery as buffer
    here, the 90W power supply is recharging the battery at 2.5A while it's being discharged at 3A on the output side, using the battery as buffer

    I made version 3 a bit smaller, with a built in 12V lipo to act as buffer for a smaller power supply. Yes, it's a beautiful piece of art, I know :)
    I made version 3 a bit smaller, with a built in 12V lipo to act as buffer for a smaller power supply. Yes, it's a beautiful piece of art, I know :)

    Pushed to the extreme, I can now use my original external battery pack again by having it recharge my lipo+150W step up that can output more amps than the ravpower pack can. Of couse, it's inefficient, the ravpower pack outputs 20V that gets down converted to 12V by the H605 Air lipo charger, which charges the built in 3S lipo in the box, and then gets up converted back to 20V without the amp limitation (the phone used to control the lipo charger also inside the box):


    The really cool thing is that by using tlp, it's actually possible to tune the laptop down to very low power use, even when plugged in, something that windows probably can't do:

    7.3W with the screen off (and around 10W with wifi off and the screen on low dim) is not bad for a laptop that big
    7.3W with the screen off (and around 10W with wifi off and the screen on low dim) is not bad for a laptop that big

    4S Lipo vs 4x 18650 or 26650 batteries

    I do have a few lipos laying around, so that's free energy for my laptop if I'm willing to carry them. I have however found that for higher draws, the step up converter doesn't quite keep up at 20V/5A+ with just 12V input (3S), but is fine with 16V input (4S):


    That said, as I recently found out that 16650 (or better 26650) batteries are both lighter and smaller. The only thing the lipos do, is offer a better discharge rate, but while that's useful for a high power RC plane motor that can empty the batteries in 10mn, it's not needed for a laptop:


    Outside of 26650 batteries, there are other ones like https://www.18650batterystore.com/21700-p/samsung-50e.htm .

    26650s are 195 Wh/kg while the lipo I gave was 184Wh/kg. The 3rd battery listed is supposed to be 260Wh/kg which is much nicer, that said, it looks like those samsung batteries are actually smaller than 26650s, lighter, and yet offer the same 5Ah at 3.6V. If so, that's very impressive.

    As of this writing, I have however not found 26650 battery holders that hold 26650 protected cells that are a bit longer. This seems to the be only one available, and it's too short to hold the batteries: https://www.amazon.com/gp/product/B074GVPWSH


    Conclusion

    Lenovo, please make the P73 work like the P70, and fix this airplane mode thing that turns off the external power supply. That's embarrassing...
    2020/05/01 Finally did the Montebello to Back Mountain to PageMill Loop
    π 2020-05-01 01:01 in Exercising
    It's a loop I knew was possible after biking up Montebello some 10 years back, but going all the way to Pagemill seemed a bit daunting. Turns out, it wasn't and it's only a 25 mile loop, albeit with a 2600ft climb. (click on the garmin recording for more stats and a bigger map)

    Here is the navigation track on google maps

    Took about 25mn and 4 miles to get to the bottom of montebello (600ft altitude), and then we biked up. Jennifer did better on the way up than I did (last time, many years back, it was the other way around):



    then up
    then up




    more up
    more up

    took about 1h from the bottom to get to ridge (4 miles, 1600ft climb)
    took about 1h from the bottom to get to ridge (4 miles, 1600ft climb)


    welcome to the top before entering the preserve
    welcome to the top before entering the preserve

    not a terrible time for a 2000ft climb
    not a terrible time for a 2000ft climb


    new gogle campus
    new gogle campus




    top of black mountain
    top of black mountain

    2h, 2500ft up to the top
    2h, 2500ft up to the top

    the fire road was challenging at times
    the fire road was challenging at times

    the hiking path was nicer
    the hiking path was nicer



    we got to pagemill in no time
    we got to pagemill in no time

    Jennifer got to practise her downhill biking skills
    Jennifer got to practise her downhill biking skills

    nice views from pagemill
    nice views from pagemill


    I know this turn from driving up, can't clip the apex on this one :)
    I know this turn from driving up, can't clip the apex on this one :)

    we took Mt Eden road as a shortcut back home
    we took Mt Eden road as a shortcut back home

    We then got back to foothill and biked home:



    Very nice loop, glad that we did it.


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