TT-Chassis 001 - Basic - 430 x 170 x 65

• Standard size (W x H x D): ca. 510 x 220 x 210 mm
• Suitable for chassis size: 430 x 170 x 65 mm
• Chassis Cut Out: ca. 410 x 55 mm
• Tolex: Marshall black
• Hardware: Marshall Gold
• Keder / Piping: Gold
• Weight: ca. 4,5 kg
• Wood: 12 mm Birch
• Dovetail joints
• Made in Germany

• Size (W x H x D): ca. 660 x 230 x 210 mm
• Chassis Cut Out: ca. 420 x 58 mm
• Tolex: Marshall Style Levant black
• Hardware: Marshall Style Gold
• Keder / Piping: Gold
• Weight: ca. 5.5 kg
• Wood: 12 mm Birch
• Dovetail joints

Specifications

• Size: 462 x 230 x 215 mm (Outside), 432 x 200 x 215 mm (Inside)
• TT Chassis: TT Chassis 001 ( not included)
• Hardware: No Hardware included
• Weight: ca. 4 kg
• Wood: 15 mm Pine Plywood

• Standard size (W x H x D): ca. 610 x 230 x 210 mm
• Suitable for chassis size: 430 x 170 x 65 mm
• Chassis Cut Out: ca. 410 x 55 mm
• Tolex: Marshall black
• Hardware: Marshall Gold
• Keder / Piping: Gold
• Weight: ca. 4,5 kg
• Wood: 12 mm Birch
• Fingerjoints

• Power Rating: 0,25 W
• Voltage Rating: 250 V AC
• Tolerance: 20%
• Shaft: 6,35 mm, Solid Shaft
• Shaft length: 15 mm
• Drill Ø: M8 (7,8 mm)
• Termination: Solder lugs
• Dimension: 24 mm

• Power Rating: 0,25 W
• Voltage Rating: 250 V AC
• Tolerance: 20%
• Shaft: 6,35 mm, Solid Shaft
• Shaft length: 15 mm
• Drill Ø: M8 (7,8 mm)
• Termination: Solder lugs
• Dimension: 24 mm

Power Jack, Chassis mount

• Schurter 6162.0046
• Ratings IEC: 10 A / 250 VAC; 50 Hz
• Ratings UL/CSA: 15 A / 250 VAC; 60 Hz
• Dielectric Strength:    
  • > 3 kVAC between L-N
  • > 1.5 kVAC between L/N-PE (1 min/50 Hz)
• Allowable Operation Temp.:-25 °C to 70 °C
• Degree of Protection: from front side IP 20 acc. to IEC 60529
• Protection Class:Suitable for appliances with protection class 1 acc. to IEC 61140
• Material: Housing PA6, black, UL 94V-0

• Springs: 3
• Delay type: Medium
• Size: Long
• Input: 10 Ω
• Output: 2.575 Ω
• Connector: Input isolated/output grounded
• Interlock: No interlock
• Mounting: Horizontal / open side down

• Type: Chickenhead
• Material: Phenolic
• Shaft Size: 6 - 6,3 mm
• Size: 32 x 13,7 mm
• Mounting: Set-Screw

• Mounting caps: Steel, nickel plated
• Color: Brown
• Mounting hardware: included

Kit of a bias probe for indirect measurement of the quiescent bias current of a tube. The adapter is placed between the tube and the socket and is connected to a standard voltmeter (not included). Pay attention to the quality of the meter and to sufficiently charged batteries!

The quiescent current is measured indirectly via a precision resistor built into the adapter. The advantages of this measuring method are harmless voltages in the mV range at the measuring plugs as well as short ways for the current, since it does not have to be led through the measuring device (common practice with many measuring adapters of Far Eastern production). As a result, there is no risk of oscillation of the amplifier, which could damage the tubes or the amplifier itself.

Note: This adapter cannot be used when additional tube brackets are installed. These must be removed before using the measurement adapter and reattached after the measurement is complete.

Measurement procedure
Determine the resistance of the adapter, including the test leads. Connect the adapter to the meter, but do not connect it between the tubes and the amplifier. Select the ohms range on the meter and note the reading, e.g. 1.1 ohms.
For the final measurement, insert the adapter between the tube and the de-energized amplifier, connect it to the meter, select the mV range and switch on the amplifier. When the amplifier has reached a stable operating condition, read the value in mV from the meter and calculate the quiescent current using Ohm's law.

Example
Measured voltage = 47 mV, adapter resistance = 1.1 ohms.
Formula (I = V / R) or in this case
Bias Current (in A) = Measured Value (Voltage in V) / Measured Value (Resistance in Ohm)
0.047V / 1.1 Ohm = 0.042A or 42mA

For the calculation of the correct bias current as well as further information on bias measurement please refer to further documents or the bias setting instructions in the info section as well as the manual of the amplifier itself.
This adapter is suitable for all EL34, 6L6, 6550, KT88, 6V6, 6CA7 and other tubes with the same pinout.

Attention HIGH VOLTAGE ! Measurements and work on tube amplifiers should only be done by qualified personnel.

Files:

• Datasheet

• Type: Noval Socket Belton VT9-ST-C
• Version: Chassis mount
• Termination Style: solder lugs
• for Tube Type: 12AX7, 12AT7, 12AU7, EL84,
•   EZ81, EL844 etc.

• Springs: 2
• Delay Type: short
• Size: long
• Replacement: Fender

• Type: Toggle Switch
• Version: SPST, ON - OFF
• Rating: 15A / 250VAC, 10A / 400VAC
• Contact resistance: 10 mΩ max. at 1A 2VDC
• Insulation resistance: 1.000 MΩ min. at 500VDC
• Dielectric strength: 2.000 Vrms 50 Hz min.
• Operating Life: 10.000 cycles at full load
• Termination Style: solder lug / quick-connect terminals

Files:

• Datasheet