Thursday, July 23, 2009

how to... use a grill made for 125VAC in europe with 220VAC power

A grill is a resistor... not sensitive to absolute voltage but rather to the Ohm effect from P= U.I
how to easily decrease the power of the 220VAC lines then?
i use a diode resisting to 10 Amps and isolated for 400V mounted on an aluminium sheet. why 10 Amp? the max power of the grill is 750W for 125V so "Imax"= 6 Amp, however, since it is 220 V that i will plug it into, i should expect twice that max intensity.. 12Amp maximum but only for a really short time for each period... there was no cheap 12A diode in the store...

so the diode will avoid to have both the phases of the sinusoide passing through the resistor, thereby decreasing the power to normal use under "1/2 pulsed" 220 VAC

The connections on the pics are rudimentary but safe. The electric isolation of the heat dissiparor will come later. I noted the diode 's heat radiator does not heat up too much which is good :)


Saturday, July 04, 2009

Kentucky holidays summer 2009

Sarah had her "1 st step" exam on the 22 nd june and i had planned to arrive just after she is done.
i had my bag kind of mishandled by Philadelphia's airport people (had to fix it) ... and also kind of lost... we had to come back to take it 1 h after i arrived in Nashville.

hey, that could be my bag!

Mammoth Cave Nationnal Park, Kentucky

At first we had booked a campground but we realised it was localised really close to the motorway so we moved to the National park campground which did not have a swimming pool but was less noisy.

The campground: nice and full of trees above us, the nature was everywhere surrounding us, we met some dears families by day and by night... one night we woke up seeing the shadow of a huge creature projected on the side of the tent... SCARY!! ouff

Another 1 match fire by Super Sarah... which was amazing because it had rtained the night before!

Showers were inexistant in the campground, had to go the the neighbouring shop and pay 2 $ to get non smelly and shiny. Most of the americans that do camping with a mobile home must be aware that some campgrounds do not offer electic plugs on each of the locations.. so they have generators for air conditionning... that is quite annoying to hear that running all the time!
something to be aware of is the presence of ticks in the trees... and snakes ... aaahhhh, did not see any but i think i would have run real fast...

A dangerous plant for humans growing a bit mainly at the bottom of trees : poison ivy. touch it and you will have strange epidermic allergic reactions that can be really bad. If the plant is burned, the toxic substance goes into your lungs and you can be seriously intoxicated. Harmless for annimals... dears eat it! hope they like it a lot...

here is the GPS acquired track of the walk we did :)

Crawling into the cave

we took the discovery tour and crawled into some of the caverns. at some point we stopped in a larger area and were asked how many times we had passed there before... we were surprised and though it was a new place... actually, we had been there twice before... this is how easy it is to get lost when there is only stones around!

In belgium, over 65 years old, you are a senior. In usa, you are "golden age" which to me does not make sense because golden age people have white hairs, not yellow, so they should be called silver age instead!

we did a bike trip in the wild tracks in the forrest (or how to get mud on your face by 40 C in the shadow). Here is the GPS followed track we did in the woods (blue line)

Canoe on Green River

on the ferry to cross Green River

Green river was more brownish than green really...There were even some mileage indications scattered along the river! is there the same along the Ardeche in France? ;)

kind of orchidee on a tree on the side of the river

here is the beach where we had lunch and later discovered some empty dinosaure eggs... oops time to go!

that little thing on my swim short that looks like a stone with lichen has legs and moves...

a desperate attempt to photograph some lightning bugs...we were told it is possible to have them lightning for longer than 2 sec... but it is a bit extreme...

Driving back to Lexington:

Lincoln's birth place (National Park)

the house they though was the birthplace was protectected by a building before people discovered it was not the original... bad luck, funny to read about the fundings for it... people giving few cents each...

Kentucky Train Museum

we look really small compared to those huge steam engines!

the dangerous couplers! read the text if interested...

Lexington's park

we also went blueberry picking... and pie cooking and degustation and digestion... i liked the eating part...

King's island for my birthday

as it was nice the last year when we went, we decided to try it in July instead of August.... but this time, we went with a part of the girl scout band friends of Sarah.

the sisters placing contact lenses.. they were crying!

the new attraction : very high! i was happy my breakfast was digested already... we were with zero gravity a few times and in free fall as well... ahhhhhhhhhhhhh

the gang

after the wild river... humm we were warned... but that time we really were targets! we were soaked from the very beginning... my shoes made floc floc every step i made for a few hours...

the girls...

the diplomatic way of saying it....

stuck on the seat with a huge acceleration...

we finished with the snake roller coaster again... we were on the end of the path when the fireworks began... hard to see without the glasses on...

Sorry girls... the photo is too dark.

4 th july parade for the US national day

Somehow i got enrolled to be the photograph of the music band Sarah was playing flute with. i even had the chance to drive a fully automatic little car (like a golf course car). Fun to do and i can add it on my cv ( - can drive a small car, in the chapter: "what can I do that a monkey can do too")

Who is Miss Lexington ?

(that's me behind the camera)

(the gps track of the parade is in pink)

back to Nashville... and Popsickes!!!! kind of mexican ice cream made out of fruits and other miam stuff!
A storm on the way to nashville.. the sky is falling!

and also the beginning of 3rd year class work for Sarah...

... in class ... and the medical student's guru!

the indian vegetarian restaurant with nice spicy food :)

Sarah was disappointed as her meal was not as large as mine although i was wondering where i could store all that big piece !

Having to leave...booo

Charlotte airport, waiting for the flight to Paris

sticking the gps at the window, i recorded some of the plane trip positionning while allowed to use electric systems in the plane. I recorded a ground speed of 1000 km/h... (wind speed must have been favourable).

btw, sarah succeeded at 1 st step USMLE exam!!! :)