Free helpful information related to vacuum tubes that can be downloaded from this site. To see a description of the information available, click on one of the name links below. After you've read the description, if you want to download a copy of the file, just click on the filename.
This file contains information on tube transconductance. How it is computed and how it is used. It is one of the best descriptions around. It is simple and doesn't get very deep into the math. It is an old 1940s Bell Labs document written by T. Slonczewski.
Keywords: TUBE TRANSCONDUCTANCE MUTUAL CONDUCTANCE BELL
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This file contains information on tube measurements, including mutual conductance, grid voltage, plate resistance, plate current and plate voltage. This is primarily a description of the underlaying physical aspects of the tube and how it works. The text only very lightly touches on the math. If you know Ohms law you will be perfectly comfortable reading this article.
Keywords: TUBE MUTUAL CONDUCTANCE TRANSCONDUCTANCE PLATE RESISTANCE CURRENT
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These two files contains information on how to test photodiode tubes as well as photoresistors and solid-state photodiodes. The text file describes how to perform the test, the second file shows the schematic.
Keywords: TUBE PHOTODIODE PHOTORESISTOR PHOTOCELL
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This file is a description of the common 80, 5Y3, 5Z3 and 5U4 type fullwave rectifier tubes. It also describes when and how you can substitute the tubes with other common varieties and how to replace them with solid-state diodes.
Keywords: FULLWAVE RECTIFIER TUBE
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This file is a simplified description of how rectifier tube circuits work.
Keywords: RECTIFIER TUBE CIRCUIT OPERATION
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This file is a simplified description of the differences between vacuum and gas rectifier tubes.
Keywords: GAS RECTIFIER TUBE CIRCUIT OPERATION
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This file is a one page ad for the Amphenol magic eye tube mounting assembles It includes a detailed description of the assemblies and example diagrams for wiring eye tubes into existing circuits.
Keywords: AMPHENOL MAGIC EYE TUBE ASSEMBLY
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This is a short text file that describes how to replace certain magic eye tubes with other similar magic eye tubes.
Keywords: REPLACE MAGIC EYE TUBE
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This file contains a list of magic eye tube numbers.
Keywords: MAGIC EYE TUBE NUMBERS
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These two files are from a data sheet included in a RCA UY-227 globe tube box. The first is the data sheet for the tube. The second is the license agreement. Yes, you had to open the package to read the agreement. Sound familiar?
Keywords: RCA UY-227 GLOBE TUBE DATA
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This text file is a summary of the various common cathode dual triodes produced.
Keywords: COMMON CATHODE DUAL TRIODE
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This text file describes alternate solutions to replacing tripple triode tubes.
The file was updated on 26 April 2017.
Keywords: TRIPPLE TRIODE TUBES 6C10 6K11 6Q11
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This text file contains a listing of the various triode/pentode tubes.
The file was updated on 27 April 2017.
Keywords: TRIODE PENTODE TUBES 6GH8 6AN8 6U8 ALL
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This text file is a description of grid clips and how they supress microphonics.
Keywords: GRID CLIP CLIPS MICROPHONICS SUPRESSION
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This is a zip file containing eight pages (JPG format) from a Burroughs document about their Nixie tubes including, data, characteristics and circuit designs.
Keywords: BURROUGHS NIXIE TUBE DATA
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Keywords: BURROUGHS B7971 NIXIE TUBE DATA
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This is a png file containing the schematic of the stock quote circuit board. Sorry about the poor quality, it is all we have. It is a high resolution scan of a copy of a copy of a copy of a....
Keywords: BURROUGHS B7971 NIXIE TUBE BOARD SCHEMATIC
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This is a text file containing a long and rambling history of the 6SN7 and some of its successors as well as a side trip to design issues such as getters.
Keywords: 6SN7 TUBE HISTORY GETTERS
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This is a text file containing a discussion about low voltage space charge tubes. Low voltage space charge tubes are tubes that can operate at "safe" voltages (30 volts or less).
Keywords: SPACE CHARGE LOW VOLTAGE TUBE HISTORY
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This is a text file containing a discussion about tubes used in battery powered radios. A list of the common battery radio tubes is provided.
Keywords: BATTERY RADIO VACUUM TUBE
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This is a zip file containing a scan of the 1954 Everready Radio Battery Guide for battery powered radios. This is a large format scan.
Keywords: BATTERY RADIO VACUUM TUBE
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This is a zip file containing a scan of the 1954 Everready Radio Battery Guide for battery powered radios. This is a small format scan (half the size of the large format).
Keywords: BATTERY RADIO VACUUM TUBE
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This is a jpg file containing a small format scan of the 1954 Everready Radio Battery Quick Guide for battery powered radios. This is a small format scan of the last page of the Everready Radio Battery Guide which contains a summary of the full radio battery guide.
Keywords: BATTERY RADIO VACUUM TUBE
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This is a text file containing a discussion about voltage regulator tubes. A list of the common voltage regulator tubes is provided.
Keywords: VOLTAGE REGULATOR TUBE
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This is a text file describing how to build an adapter to use a 6G11 compactron tube in place of a 6GE8 tube.
Keywords: VOLTAGE REGULATOR TUBE
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This is the substitution guide for tubes replacable by the RCA SK3756 High Voltage solid state rectifier
Keywords: RCA HIGH VOLTAGE RECTITFIER SUBSTITUTION
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This is the substitution guide for tubes replacable by Sylvania ECG Solid State HV Rectifier Parts
It consists of two jpg files stored in the zip file.
Keywords: SYLVANIA HIGH VOLTAGE RECTITFIER SUBSTITUTION ECG508 ECG509 ECG510 ECG511 ECG512 ECG513 ECG514
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This is a text file containing a description of the four basic tube tester types you will encounter, what makes them different from each other, and which will likely work for your situation.
Keywords: TUBE TESTER TYPES
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This is a zip file containing 17 pages of Hickok 539A Operator Instruction Manual including the schematics.
Keywords: HICKOK 539A TUBE TESTER OPERATOR INSTRUCTION MANUAL
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This is a zip file containing ten pages of tube setup charts for the Superior model 820 tube tester. It also includes a page describing how to use the crt test adapter with the model 820.
Keywords: SUPERIOR 820 TUBE TESTER CHARTS
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This file contains the schematic for the Jackson model 648R Tube Tester.
Keywords: JACKSON 648 TUBE TESTER SCHEMATIC
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restr666.txt Buying restoring and calibration the tester
Bytes: 48567, Date: 31-May-13 - Updated 31 Mar 2019 - Revised 31 Dec 2023
eico666-667-repair.txt Detailed Troubleshooting and Repairing the Tester
Bytes: 55502, Date: 22-Feb-19 - Updated 31 Mar 2019 - Revised 31 Dec 2023
666-667-mod.png Circuit diagram of the tester protection mods
Bytes: 11726, Date: 31-May-13 - Updated 30 Mar 2019 - Revised 31 Dec 2023
eico666meter-power-notes.txt A description of the meter calibration circuit
Bytes: 8731, Date: 14-Jul-17 - Updated 31 Mar 2019 - Revised 31 Dec 2023
eico666tester-meter-check.txt How to check the meter circuit.
Bytes: 16368, Date: 14-Jul-17 - Updated 31 Mar 2019 - Revised 31 Dec 2023
eico666parasitics.txt Parasitic oscillation problems in the Eico Tube Testers.
Bytes: 21,431 bytes, Date: 10-Mar-24
how-eico666-works.txt How the Eico 666 and 667 testers test tubes.
Bytes: 11627, Date: 1-Mar-24
eico666-667-parts.txt Eico 666/667 repair parts
Bytes: 3911, Date: 30-Mar-19 - Revised 31 Dec 2023
eico666all.zip This is a zip file that includes all of the above Eico test and repair files.
Bytes: 762,726 bytes, Date: 14-Jul-24
Click on the filenames above to download the files
These files contain information on buying, restoring, troubleshooting, repairing and calibrating the Eico 666 and 667 Tube Testers.
Keywords: Eico 666 667 TUBE TESTER BUY CALIBRATE MODIFY
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This file contains information about parasitic oscillation problems with the Eico 666 and 667 Tube Testers.
(This information relates to all tube testers, not only the Eico testers.)
Keywords: Eico 666 667 TUBE TESTER PARASITIC OSCILLATION
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This file contains information about testing tubes with the Eico 666 and 667 Tube Testers.
How to verify existing test setups and how to create your own.
Keywords: Eico 666 667 TUBE TESTER
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eico666-instruction-manual.zip
Bytes: 3.67MB, Date: 25-Mar-17
eico666-construction-manual-small.zip
Bytes: 1.86MB, Date: 4-Oct-17
eico-666-667-addenda.zip Addenda for Eico 666/667 Tube Tester Instruction Manuals
Bytes: 113824, Date: 17-Aug-19
Click on the filename above to download the file
These three zip files contain the instruction and construction manuals for the Eico 666 Tube Testers (1959 version).
Keywords: Eico 666 TUBE TESTER INSTRUCTION CONSTRUCTION MANUAL
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eico-667-instruction-manual.zip
Bytes: 9.65MB, Date: 18-Mar-23
eico-667-construction-manual.zip
Bytes: 6.51MB, Date: 18-Mar-23
eico-667-construction-figures.zip Figures (pictures) for Eico 667 Construction Manual
Bytes: 2.7MB, Date: 18-Mar-23
Click on the filename above to download the file
Note: These files are big and will take time to download.
These three zip files contain the instruction and construction manuals for the Eico 667 Tube Testers.
Keywords: Eico 667 TUBE TESTER INSTRUCTION CONSTRUCTION MANUAL
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This file contains my annotated 666-05 setup chart for 666/667 the Eico 666 and 667 Tube Testers.
Note: this is a photocopy of my chart, so it is a bit hard to read is some areas.
Keywords: Eico 666 667 TUBE TESTER 666-05A SETUP CHART ANNOTATED
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This file contains Instructions for the Eico 610A Adapter for the Eico 666 Tube Tester.
Keywords: Eico 610A 666 TUBE TESTER ADAPTER
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These files contain the Instructions for the Eico CRA, CRU and MH3 CRT Test Adapters.
Keywords: Eico CRA CRU MH3 610A 625 666 667 TUBE TESTER ADAPTER
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eico-tr1.zip Eico TR-1 Transistor Test Data Sheet
Bytes: 247,676, Date: 17-Aug-19
Click on the filename above to download the file
This file contain the Eico Transistor Test Data Sheet for the TR-1
Keywords: Eico TR-1 TEST DATA SHEET
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eico-232-249.zip Eico 232-249 VTVM Instruction Manual
Bytes: 1.52 MB, Date: 17-Aug-19
Click on the filename above to download the file
This file contain the instruction manual for the Eico 232 and 249 VTVM.
Keywords: Eico 232 249 VTVM INSTRUCTION MANUAL
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eico-337ins.zip Eico 337 Instruction Manual
Bytes: 1.67 MB, Date: 17-Aug-19
eico-337con.zip Eico 337 Construction Manual
Bytes: 1.39 MB, Date: 17-Aug-19
Click on the filename above to download the file
These two zip files contain the instruction and construction manuals for the Eico 337 Signal Generator (1952 version).
Keywords: Eico 337 SIGNAL GENERATOR INSTRUCTION CONSTRUCTION MANUAL
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bogen-wma75.zip Bogan WMA-75 Manual
Bytes: 3.49 MB, Date: 13-Apr-20
Click on the filename above to download the file
This zip file contain the instruction manuals for the Bogen WMA-75 Amplifier. Also for the RCV-2A, REM-2A and MSK-1
Keywords: BOGEN WMA-75 INSTRUCTION MANUAL RCV-2A REM-2A MSK-1
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This file contains information on radio vibrators, their operation and their replacements.
Keywords: RADIO VIBRATOR OPERATION REPLACEMENT
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This file contains information on transformer wiring color codes.
Keywords: TRANSFORMER COLOR CODE
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This file contains information on ballast resistor identifier codes.
Keywords: BALLAST RESISTOR TUBE CODE
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This file contains information on how to build a voltage doubler to drive a 12.6V tube heater from a 6.3V filament supply.
Keywords: TUBE FILAMENT POWER SUPPLY DOUBLER
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This is a text file containing a discussion about hearing aid batteries. A list of the common battery types is provided.
Keywords: BATTERY HEARING AID
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This is a text file containing a discussion about problems with ceramic capacitors.
Keywords: MLCC CERAMIC CAPACITOR PROBLEMS
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The Stanley GMF64020ABTW datasheet in the form of a pdf file.
This is a 640x200 LCD display. The display area is 70mm tall by 210mm long.
Keywords: STANLEY GMF64020ABTW DATASHEET
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Links: Go back to the TOP , MDB Ventures Home,
Email: MDB Ventures info@mdbventures.com or info@fourwater.com