Posted on Sunday, 19th April 2009 by Auw Jimmy

I dig my tube boxes and found this old tube. Not a really expensive or most wanted tube, yeah… just an old Western Electric 393A tube. It’s a Argon and Mercury Vapor filled Thyratron tube. According to the datasheet, the addition of Argon gas on the Mercury Vapor atmosphere allows the tube to start conducting at low temperature. Ok, forget those technical literature, just watch the tube in action.

I heat up the tube for a while. According to the manual, to maintain the life span, it’s recommended to heat it up first. I give around 3-4 minutes. You can see the filament is glowing inside the metal bracket on the center of the tube.

Time for action, activate the High Voltage… Voila, the sky of blue on the top of the tube. Very beautiful!!! You still can see the red filament glowing inside the blue Mercury atmosphere.

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Tags: glowing, Mercury, tube, tube tester
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Posted on Sunday, 19th April 2009 by Auw Jimmy

Being a perfectionist is not easy (and not cheap). Still remember my ambitious project before? I want to make it perfect, so let’s start the 1st phase, testing the capacitor (I mean, the Black Gate)

I will use 60 Black Gate capacitors on the power supply. First 30 pcs for positive rail, and another 30 pcs for negative rail. I want both rails have similar capacitance (or as similar as possible). So first capacitor on positive rail will have similar capacitance value on first capacitor on negative rail. Too perfectionist?

I need to know exactly the capacitance of each Black Gate. You know that every capacitor has around 10% tolerance. So when it’s written 680uF, it may vary between 680-68 or 680+68. Who knows? The meter knows.

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Tags: Black Gate, power supply
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Posted on Sunday, 19th April 2009 by Auw Jimmy

It’s time for Single Ended amplifier benchmarking session. Located at Bakmi Margonda, Sarinah, Indonesia.

Here is some shoot from the event. The system was very simple, Tannoy speaker, Audio Aero Capitole CDP, and AirTight 300B as Reference Amplifier.

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Tags: Amplifier, Blind Test, single ended, tube
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Posted on Sunday, 12th April 2009 by Auw Jimmy

One factor that makes me like tube is its glow. Well, it’s hard to explain, but some tubes have a beautiful color, especially in dark room. Here is some of them.

Below is the 0A3/VR75 tube. It has red/fire color. Very bright and aggresive.

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Tags: Knight, Mercury, rectifier, tube tester, voltage regulator tube, VR tube
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Posted on Sunday, 12th April 2009 by Auw Jimmy

After previous trip to “trash bin” shop, now it’s the time to test it So I open my old Knight 600 Tube Tester and fire it up.

Picture below shows my Knight 600 testing Amperex 6BQ5/EL84 tube. Not bad! No short or what-so-ever.

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Tags: el84, knight 600, tube tester
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Posted on Saturday, 11th April 2009 by Auw Jimmy

Amperex 6BQ5/EL84 from “trash bin” shop Not bad for some cheap experiment!

Tags: el84, tube
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Posted on Friday, 10th April 2009 by Auw Jimmy

As I’ve promised before, my Gainclone project will be supplied with special smoothing capacitors. Welcome, the Black Gate F Series 680uF/65V. Each rail (positive and negative) will have 30 pcs of Black Gate capacitor, with total around 20.000uF capacitance each rail.

The main rectifier will be MUR860 and I will also use Snubber circuit, with the help of Mills and perhaps some oil capacitor. Hope it will sound good…

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Tags: Black Gate, Capacitor, gainclone, power bank
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Posted on Saturday, 4th April 2009 by Auw Jimmy

I’m thinking of a digital volume control, instead of passive one (with potentiometer or stepped attenuator). Hmm… Searching around the net, I found some IC from Maxim. I grabbed some (with different packaging and functionality). Now I need to think how to create a new jig with this IC

Time to leave “analog” world? Well, I’m thinking about it…

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Tags: Attenuator, digital, IC, maxim, potentiometer, volume control
Posted in Collectible Stuff, DIY Audio, Personal | Comments (3)