Wednesday, December 10, 2008
Train Control: Works!
…at least, it seems.
Today is a historical date: after almost three years of development, we (me & Peter) where able to test 1/4 (half of the second track route) of the Train Control System. And It Works! Smoothly and reliably! YAHOOO!!
Monday, December 8, 2008
The Tube Amp Project The Second
Second round for the Mighty Tube Amp Project! Well, it actually took all the month (from the last post) of experiments. I have some photos somewhere but I couldn’t find them. Saturday it was THE DAY. I mean, THE DAY when the sky opens and the Angels play the trumpets, the birds come singing, the sun rays enter the room and you find the The Answer to the Ultimate Question of Life, the Universe, and Everything (which apparently, is not 42 [and no, I am not a fan of the books…]). Yes, it was the day that the amplifier ALMOST worked. With the pot at maximum power, it DID NOT oscillate and furiously squeal! Also, the perfect (hehe) rewiring and power supply generates no hum whatsoever. Well, the remaining little issue is that the ampli is unusable at every power wich is not min or max… oops!
Some nice photos of the event… Horrible since I forgot the cam:
Tuesday, November 11, 2008
The Tube Amp Project
Long long ago, me and Peter decided it was time to build a tube amp. Enough ugly transistors FETs and friends! We want the warm and cozy sound of a valve!
The first problem is finding a simple enough schematic… too many to choose from! Start with an EL84? And the output transformers? Argh! The project finally settled down to this:
http://www.tubebuil … ended/ecl82_se2.gif
A simple simple ECL82 tube amp. After buying some 70’s russian tube on ebay from a guy in Ucraine, the power transformer in Milano and the output ones in Canada, we where all set.
Construction went smoothly (after all, just ~ 10 components!) but at the first power up it was nore SIREN than amplifier.
WAAAAAAAAAAAAAAAAAAAAAAAAAA!
An investment in more decent output transformers did not change matters. Well, after meny rebuilds and many sirens the project was abandoned.
Until sunday. A friend told us that to stop the oscillator effect you just have to add a series resistor with the triode’s grid. Presto! we have to do it! after all, HE built a working ampli! Well, huess what… adding the resistor does NOT work. Sob. BUT if you remove the 10nF cap at the imput (before the new resistor) well… it works! Sort of, actually. But it oscillates MUCH less. So we arrived at the conclusion that th schematic is incorrect (and we are not able to build tube amps). Some photos of the event:
Peter working! Incredible!
Warm glowing tubes on Peter’s ampli.
My ampli. All the components are on the tube socket.
Hemm… note the CONNECTED plug!
My nice glowing tube!
The &%@%# schematic
Testing!
Warm and cozy…
Sunday, November 9, 2008
Repair day!
Yesterday was repair day. I had te right inspiration to finally repair my super8/regular8 film viewer. This thing has two little prisms wich rotates to generate the image on the screen, one for super8 and one for regular8. Well, something like 10 years ago the regular8 prism detached from it’s housing making unusable the regular8 part. I tried many times opening the prism’s box but I never found the right path. Yesterday I was particularly inspired and I finally was able to open it up. It seems in the past years I did not find the screw under the front bezel…
Here is the prism’s housing, with the super8 and broken regular8:
And here after the simple repair:
While I was in repair-mood I did also repair the BR94:
Saturday, November 8, 2008
Film Reels & The Big Sola(tm)
Yesterday my dear AL brought me two bags full of film and magnetic spools:
It seems to be a collection of home movies from the ‘60 in regular 8mm. Mostly kodachrome and some BW films. There are too some magnetic recordings. Unfortunately I don’t have a reel to reel recorder for them :(
These films seem in quite good condition, but some of the BW prints smell quite vinegar-ish, so they will remain in quarantine. I did not attempt to project any of them since I want to verify the tape slices, but on a close inspection these films seem beautiful! The author made titles and a real cutting of the scenes!
This little guy will have some work to do:
The Sola
A couple days ago arrived a Fleischmann BR94 I brought on ebay. This is my first “bad” auction. It was advested ad “excellent condition” but THIS made me wonder…:
Humm… DEFEKT?? Yes! here you can see the defect:
The &^#@^& seller was wise enough to disguise the defekt in the photo on the auction! This will probably be the first negative. feedback i leave… AND I will have to repair it now!