Альтернативное отмечание 4-ого июля и ламповый усилитель (Best 4th of July Ever!)

Sorry for Russian, I will put the English translation a bit later. But the photos are still good :-).

Какое-то время назад я писал о дзэн-идее изготовления ламповых девайсов. Потихоньку я собирал нужные детали и материалы, и наконец, на прошлой неделе, все было готово к тому, чтобы отметить 4-ое июля альтернативным методом. Массовые мероприятия я не очень жалую, так что приглашениям был дан отбой. Последнее время я был весьма загружен, так что надо было как-нибудь расслабиться и отдохнуть, и сборка лампового усилителя для наушников подходила идеально. 3 июля ушло на подготовку шасси, пополам с обычной работой, а 4 июля я приступил к празднованию. К вечеру аппарт был собран и запущен (вид в полутьме, индикаторные светодиоды заклеены):



На свету:


Схему самого усилителя я воспроизвел без каких-либо изменений, используя 6922 и 6AS7G (обе RCA Radiotron, old stock, не б/у, подарок одного хорошего человека). Источник анодного напряжения хотелось собрать на кенотронах, что и было сделано (китайские EZ81, JJ Electronics). В качестве основы использовал схему от Ying Mingyao, внеся в нее небольшие изменения. Вместо дросселя на 8 генри стоит 12 генри. Поскольку один Hammond 269BX накал всех четырех ламп не потянул бы, пришлось поставить дополнительный накальный трансформатор Hammond 167R6. В отличие от оригинального исполнения, накал всех ламп осуществляется переменным током, а также блок питания и сам усилитель размещены в одном корпусе. Благодаря хорошим советам, наводок не слышно даже на максимальной громкости. Дроссель (находится впереди слева на шасси) смонтирован под углом для уменьшения наводок. Это положение нашел экспериментально, подключив к выводам дросселя осциллограф и держа силовые трансформаторы под напряжением (на пустом шасси).

Не мог не использовать еще один подарок, старое тепловое реле задержки:



этот элемент (Amperite, 300 секунд задержки) активирует обычное реле, которое отключает его нагревать, подает питание на свою собственную обмотку, подает высокое напряжение на кенотроны, и включает зеленый светодиод. Под ним (светодиодом) расположена кнопка которой можно включить анодное питание до сработывания реле задержки. Красный светодиод включается сразу же, работает индикатором питания (расположен над общим выключателем питания справа).



разъем для наушников (см. фото выше) и RCA входы пришлось смонтировать на текстолитовых пластинках, чтобы изолировать их от шасси:



устройство смонтировано на стальном шасси (Hammond, model 1441-29BK3, 12''x10''x2'', black finish). Вид на подвальное помещение:



Заработало сразу, без какой-либо настройки или доводки. Звучит очень хорошо, даже с 32-х омными наушниками. На слух басы воспроизводятся хорошо (больше всего о них беспокоился). Опять же, на максимальной громкости (без входного сигнала) не слышно ничего, ни сетевых наводок, ни шумов. В целом очень доволен, усилитель очень прост в изготовлении и замечательно звучит.

Masters of Deception: Rob Gonzalves.

The last painting, which is the one used as the book's front cover art. "The Sun sets Sail", acrylic on canvas, 2001:
Here is a link to a big collection of his work, 37 paintings.

Masters of Deception: Sandre Del-Prete.

Another couple of scans from "Masters of Deception" to convince people to check out this book. "A Secret between Leaves", 1991, colored pencil drawing:"Homage to Leonardo da Vinci", 1992, colored pencil drawing:

Maker of Patterns.

A mathematician, like a painter or poet, is a maker of patterns. If his patterns are more permanent than theirs, it is because they are made with ideas.

G.H. Hardy

Masters of Deception: Rex Whistler.

Today I returned "Masters of Deception" to the library, but before I made some promotional scans :-). Here are some works of Rex Whistler (1905-1944). It has such a vintage feel to it, and the work itself is very interesting. It's the same drawings, just flipped by 180 degrees.
"Change of Expression", undated pencil drawing:
"A King and his Queen":
"Surprise!":
Excerpt from the Wikipedia article (much the same, although a bit less detailed story is given in "Masters..."):

On the hot and stuffy 18th July his tank, after crossing a railway line, drove over some felled telegraph wires beside the railway, which became entangled in its tracks. He and the crew got out to free the tank from the wire when a German machine gunner opened fire on them, preventing them from getting back into their tank. Whistler dashed across an open space of 60 yards to another tank to instruct its commander, a Sergeant Lewis Sherlock, to return the fire. As he climbed down from Sherlock's tank a mortar bomb exploded beside him and killed him instantly, throwing him into the air. He was the first fatality suffered by the Battalion in the Normandy Campaign.

Agent Smith as Carl Sagan.

it's absolutely hilarious:



In order to get the joke, we need to know about Carl Sagan's Cosmos: A Personal Voyage. Here is a good short clip to get acquainted with the show, and certainly enough to enjoy the joke above. It's also a very good explanation of the concept of 4th dimension, so no time will be wasted:

Чистая медь.

В связи с завершением большой серии экспериментов сегодня решил сделать что-нибудь простенькое для души. Я уже давно хотел сделать себе несколько образцов меди с чистой поверхностью. У чистой меди очень красивый цвет, тепло-розовый, без всяких признаков желтизны. Но на воздухе она быстро покрывается оксидами и т.п., поэтому единственным выходом для длительного хранения было запаивание. Порошок электролитической меди и стружки меди неизвестного качества были промыты разбавленной соляной кислотой, потом водой, потом несколько раз спиртом, высушены в ваккуме водоструйного насоса, (для очистки совести) продуты азотом и запаяны в толстостенные пирексовые ампулы. Неплохо получилось, тут поверность уже не измениться! No matter what...

Порошок меди вблизи, уже чистый и в ампуле:

"Edward Lorenz, father of chaos theory, dies"

Sad news. By way of homage to the great scientist, here is a very good Lorentz applet, demonstrating chaotic behavior (sensitivity to the initial conditions).

But the butterfly lives on.

Crepuscular Fox.

Yesterday morning waking up early really paid up :-). At 6-20am I saw a fox strolling onto a lawn of own apartment complex. It stopped to eat something crunchy (I could here it from my balcony). Fortunately, I had my camera handy:Sorry for the poor quality, I took this photos with full zoom (and it was during twilight).

P.S. Crepuscular - becoming active at twilight or before sunrise.

Jug Dome.

Another day sport climbing, this time at the Jug Dome. This place hosts several long sport climbs of good grades (5.7-5.11). People on mountainproject point to longish approach, but it takes only ~15 minutes. Pretty steep, though. First we did Law School in one pitch, which gave a great opportunity for some photos at the top. Here is a hero-shot of Shamil' at the beginning of the rappel. I love pine trees and snow on the background:Such an alpine photo! And to give you a feel for the length of the route here is a view from the top:and from the bottom:In that photo I'm rappelling a line of Dick Van Dike, which we climbed next. Then we decided to climb another route. Somehow instead of doing the Black Tube, a 10b route which I really wanted to do, I got myself on Backpaddle, a 5.11a climb. Fortunately, the bolts were really tightly spaced in the crux section, so after much fighting and resting I got to the top. Shamil' did a great job catching me, since the route took some figuring out. It would be interesting to come back sometime and try to redpoint it. Moreover, we got to climb the Black Tube :-)!

Climbing at the Palace, and the Route with a View.

This Saturday (05-Apr-2008), thanks to good weather, we (Morgan, Shamil', and I), were able to open the sport climbing season. Here is Shamil' on Rappunzel, Rappunzel (10a):
and Morgan on Let down your Hair (10b):Then we jumped on the Route with a View (10b/c). Despite a considerable lure of shouting "take", I led it cleanly, which felt pretty awesome. The route is a real classic, pretty sustained, and more overhanging than it looks from the bottom. Upon making it to the anchors we decided to have a lunch at the top, so I brought guys up:Here is another shot from a different angle:Morgan did a great job of taking these photos, and then climbing with a camera and sandwiches. We spend quite a while at the top, chatting and enjoying the view. Here is a group photo:and a view:A great day in a great company!

High conquest.

After reading a fourth part of Alpinist's Inspirations, I got the "High conquest" by J.R. Ullman from the library. The books doesn't disappoint. Here is an excerpt from chapter 2, about the beginning of mountaineering in Europe:

But, in its essence, it has been a struggle not of man against man, nor even of man against the obstacles of the physical world, but of man against his own ignorance and fear.

It's an excellent book, with the right kind of spirit!

Snow shape.

Taken somewhere between Chasm Junction and a treeline:

Opening the season (Chasm Junction hike).

As an opening hike for this season we (Shamil' and me) decided to go for Chasm Junction (elevation 9400 feet), having in mind Meeker as an ultimate goal if conditions allow. We left Longs Peak trailhead at 6-40 (03-29-2008), accompanied by continuous light snow. The trail was well-packed, and we were making good progress, coming to Goblins Forest (~10140 feet) at 7-25. At 7-56 we had a short break at the lightning hazard sing (~10594 feet) and moved above the treeline. The wind was getting stronger, with some pretty good gusts and blowing snow. Occasional postholing, scrambling and head wind slowed us down considerably, but as we got higher the snow was mostly blown off, which made our job much easier.
Blowing snow really made for a very fun hike. It definitely gave some extra appreciation of the place we were in:
At 9-36 we got to the Chasm Junction (~11480 feet) and immediately went further along the Chasm Lake trail to hide from the wind. Quickly we started sinking below knee in unconsolidated snow, and with some major effort reached a hiding place by a standing rock. Here we ate and "relaxed" a bit, although wind made it pretty challenging. Half of my face was frozen from the wind, so it felt I just got numbed up by a dentist. Wind was forcing us to keep moving, so after a brief rest and a couple photos we headed down.Longs and Meeker were completely obscured by clouds and snow:At 10-03 we headed back. Soon the wind started to calm down, and by the time we reached the treeline the weather was very good again. At 12-00 we came back to the trailhead after a great day out. It was a good way to start the season - nothing strenuous, but very fun. Thanks to the weather we got some pretty stern views.

Always look at the bright side of life!

It's been long, too long in fact. I was busy, and moreover, I sort of lost the interest in keeping a blog. But I missed it, to be honest. It's fun. So I decided to start again :-).

Here is something provocative:



The lyrics:

Some things in life are bad
They can really make you mad
Other things just make you swear and curse
When you're chewing on life's gristle
Don't grumble, give a whistle
And this'll help things turn out for the best
And...

...always look on the bright side of life
{whistle}
Always look on the light side of life
{whistle}

If life seems jolly rotten
There's something you've forgotten
And that's to laugh and smile and dance and sing
When you're feeling in the dumps
Don't be silly chumps
Just purse your lips and whistle - that's the thing

And... always look on the bright side of life
{whistle}
Come on
Always look on the bright side of life
{whistle}

For life is quite absurd
And death's the final word
You must always face the curtain with a bow
Forget about your sin - give the audience a grin
Enjoy it - it's your last chance anyhow

So always look on the bright side of death
Just before you draw your terminal breath
Life's a piece of shit
When you look at it
Life's a laugh and death's a joke, it's true
You'll see it's all a show
Keep 'em laughing as you go
Just remember that the last laugh is on you

And always look on the bright side of life
{whistle}
Always look on the right side of life
{whistle}

Come on guys, cheer up

Always look on the bright side of life...

Always look on the bright side of life...

Worse things happen at sea, you know

Always look on the bright side of life...

I mean - what have you got to lose?
You know, you come from nothing
- you're going back to nothing
What have you lost? Nothing!

Always look on the bright side of life