Shaun Merrigan's Information Pages


Category: Vacuum Tubes


Vacuum Tube Tester: The Roetest

Posted by Shaun Merrigan in Electronics, Tech, Test Equipment, Vacuum Tubes. Comments Off on Vacuum Tube Tester: The Roetest

17th March

I recently completed the construction of a PC controlled vacuum tester: The Roetest. This is a computer-controlled tube tester which works as follows:

Using the PC software, load the tube data from the extensive database

Verify the tube data and pinout on the screen; the tester configures the pin connections automatically

Run the tests for shorts and filament continuity

Run the required tests

Test the tube at full voltage and current (not a pulse test)

Save the result

Add the tube and test data to inventory

Roetest V10 Front Panel and case

Roetest V10 Main board and plug in boards

Roetest V10 Front Panel

Construction Details:

4600 Solder Joints

600+ Components

20 separate circuit boards

Mechanical work for socket boxes + drilling and tapping heatsink

150+ hours

Using the PC software, load the data for the TUT (Tube under Test). Pinout and base connection information is taken from an extensive database of over 22,000 tube types.

Roetest … Read More »


The uTracer Tube Tester and Curve Tracer

Posted by Shaun Merrigan in Electronics, Vacuum Tubes. Comments Off on The uTracer Tube Tester and Curve Tracer

14th August

The uTracer Tube Tester and Curve Tracer

I have completed building my uTracer (micro Tracer) computer based vacuum tube tester and curve tracer.  This unit, designed by Ronald Dekker described on his website:

The uTracer is much more than a simple tube tester; it is also a curve-tracer. It measures both the anode as well as the screen currents for a range of specified bias conditions, and arranges the measurements in meaningful sets of curves. From these curves parameters like the transconductance or the output resistance can then be extracted and plotted as a function of bias. Alternatively the uTracer can be used as a tester which extracts important parameters like Ia, Rp, gm and um in your favorite bias point in a matter of seconds. http://dos4ever.com/uTracer3/uTracer3_pag0.html

Ronald Dekker makes this tester available as a kit, with detailed assembly and testing instructions.  One of … Read More »


Tektronix 556 Fan Motor Repair Part 1

Posted by Shaun Merrigan in Electronics, Oscilloscopes, Tektronix 556, Vacuum Tubes. Comments Off on Tektronix 556 Fan Motor Repair Part 1

19th January

Tektronix 556 Fan Motor Repair Part 1

I was recently fortunate enough to acquire a Tektronix 556 Dual Beam Oscilloscope with many accessories and in good condition.  Unfortunately, the cooling fan on the scope was very loud and more concerning, it emitted an alarming metal on metal contact sound.  After verifying basic operation of the oscilloscope, I decided to repair the cooling fan.  This process is documented in the images and commentary that follow.

Part 1: Removing the Noisy Fan Motor

556 Cooling Module with filter and mesh screen removed.  The fan is connected to the chassis wiring at the ceramic terminal which is circled:

556 Fan Cooling Module Outside

Fan to chassis wiring connection terminal.

 

556 Fan Cooling Module Fan Connections

Inside of cooling module and bottom side of motor (fan blade removed):

556 Fan Motor Underside

Back side of motor (fan blade … Read More »


New Vacuum Tube Box Scans

Posted by Shaun Merrigan in Electronics, Vacuum Tubes. Comments Off on New Vacuum Tube Box Scans

6th January

New Vacuum  Tube Box Scans

I have uploaded several new vacuum tube box scans including Philco, Canadian General Electric, Wards, and Hitachi (Hit-Ray):

 

Wards Tube Box_3

Wards Tube Box_2

Wards Tube Box_1

Philco Tube Box_4

Philco Tube Box_3

Philco Tube Box_2

Philco Tube Box_1

Motorola Small Tube Box_4

Motorola Small Tube Box_3

Motorola Small Tube Box_2

Motorola Small Tube Box_1

Lafayette Tube Box_4

Lafayette Tube Box_3

Lafayette Tube Box_2

Lafayette Tube Box_1

Hitachi Tube Box_4

Hitachi Tube Box_3

Hitachi Tube Box_2

Hitachi Tube Box_1

CGE Radiotron Tube Box_2 (4)

CGE Radiotron Tube Box_2 (3)

CGE Radiotron Tube Box_2 (2)

CGE Radiotron Tube Box_2 (1)

Wards Tube Box_4

 

Thanks,

 

Shaun M.


Tektronix 556 Dual Beam Oscilloscope Images

Posted by Shaun Merrigan in Electronics, Oscilloscopes, Tektronix 556, Vacuum Tubes. Comments Off on Tektronix 556 Dual Beam Oscilloscope Images

31st December

Tektronix 556 Dual Beam Oscilloscope Images

What follows is a series of images of my Tektronix 556 Dual Beam Oscilloscope displaying various waveforms.  I am learning about this scope and how to use it.

A brief description of the unit can be found here: Tektronix 556

Tektronix 556 Oscilloscope: Square Waves, one channel per beam.

Tektronix 556 Oscilloscope: Pyramid waves, two channels per beam

Tektronix 556 Oscilloscope:Pyramid waves, two channels per beam

Tektronix 556 Oscilloscope:Pyramid waves, one channel per beam

Tektronix 556 Oscilloscope: Two channels per beam, no inputs grounded.

 

Thanks for reading.

 

Shaun M.



Fallout 4 Vacuum tubes and Nixie tubes

Posted by Shaun Merrigan in Gaming, Nixie Tubes, Tech, Vacuum Tubes. Comments Off on Fallout 4 Vacuum tubes and Nixie tubes

8th February

Fallout 4 Vacuum tubes and Nixie tubes

I have been working my way through Fallout 4 and during my explorations I noticed that the labs and military installations are loaded with vintage vacuum tube equipment.  I thought I recognized the front panel of at least one piece of gear:

Front Panel render from Fallout 4 (Bethesda Softworks):

Fallout 4 Front Panel

 

 Now compare this image with the front panel of the Racal RA-17:

Racal RA17 Front Panel

The resemblance of the Fallout 4 render to the real Racal RA17 is striking.  This Racal-like front panel appears in nearly every lab and/or military installation that I have explored.

Another rack of equipment very frequently seen in labs and military installations is this one:

 

Fallout 4 Equipment Rack (Bethesda Softworks

Fallout 4 equipment rack

This image clearly shows:

A nixie tube … Read More »


Numitron Clock Project

Posted by Shaun Merrigan in Tech, Time and Frequency, Vacuum Tubes. Comments Off on Numitron Clock Project

21st February

Numitron Clock Project

Numitrons are low voltage incandescent display devices perfected and marketed by RCA (see RCA advert above) in the early 1970’s.  I would call this a bridge technology as the display is incandescent, but can be driven by integrated circuits.   They were quickly displaced by solid state LED (light emitting diode) devices from the mid 1970’s onward.

This is a Numitron:

RCA Numitron Advert

The look and feel of a Numitron display appeals to me and I wanted to reboot my building and soldering skills , so I decided to build a Numitron clock.  I based my clock on the RCA DR2000 which has a beautiful 15mm display height and a board and parts kit (no longer available) from Richard White.  Here are some images of the construction process:

  

And here is an image series of the finished clock … Read More »


New Vacuum tube box scans

Posted by Shaun Merrigan in Site Updates, Tech, Vacuum Tubes. Comments Off on New Vacuum tube box scans

29th October

New Vacuum tube box scans

I have added several new images to my gallery of Vacuum Tube Box Artwork.

The new images include Westinghouse, Tung-Sol and Quality Brand tube boxes.

 

Quality Brand Tube Box Side 2

Westinghouse TV Receiving Tube Box Side (4)

 

Shaun M

 

 


New Section added: Vacuum tube glow, box scans and artwork

Posted by Shaun Merrigan in Site Updates, Tech, Vacuum Tubes. Comments Off on New Section added: Vacuum tube glow, box scans and artwork

27th October

New Section added: Vacuum tube glow, box scans and artwork

In the spirit of both preservation and exploration, I have added a new section to the the under Photography: Vacuum tube glow, box scans and artwork

Here I will be documenting the artwork used on vacuum tube boxes as well as showing some of the images I have captured of vacuum tubes while they are operating.  I will be adding more images over time as I work through my vacuum tube inventory.

 

12AU7 “Blue Glow”