Airmail version 3 is now released for general consumption in two editions. Click one of the following links to go to the appropriate Airmail-3 page for download files and instructions: Airmail 3.0 for ham users. Airmail 3.0 for SailMail users. Airmail’s Weatherfax Companions (Grib/fax Viewer, weather-fax program). Crop jumper Round neckline Long sleeves Drawstring waistline Match it with Sia Trackpants Model is wearing size S Height: 180cm Bust: 86cm Waist: 61cm Hips: 92cm Material: cotton polyester ESTIMATED DELIVERY: 2 - 5 Business Days in Australia. First Airmail Issues (The “Curtiss Jennys”, 1918): Scott #C1, C2, and C3 With air mail service scheduled to begin May 15, 1918, there was an urgent need for air mail stamps. A Congressional act signed on May 11th authorized the Postal Department to carry air mail at a rate of twenty-four cents per ounce. Make sure “Account Active” is checked, and then click OK. Airmail will send a settings-message to the server and it will start monitoring your account. Mail is checked every 6 hours and you will get a message from the server (“shadow-reply@saildocs.com”) whenever new mail is. 6 Airmail routes, July 1, 1934 On February 9, 1934, Postmaster General James Farley canceled all domestic airmail contracts following a political scandal. For several months the Army flew the mail, at the direction of President Roosevelt. New airmail contracts were signed with domestic carriers in April and May 1934, for more service at less cost.

DIY and Hi-Fi Audio Schematics

This is our collection of DIY and Hi-Fi Audio Schematics. Feel free to send us your hi-fi audio schematics and we will add them here. If you have built any of these circuits, we would love to hear from you so send us your comments.
Many of these diy Audio Books contain schematics. You can also find more schematics through some of the sites noted on the DIY Audio Links page.
Last update: 24 July 2016

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DIY Audio Schematics

Tube Linestage Preamplifiers

  • 4S Universal Preamplifier for 12A*7 Tubes - (Project) NEW
  • 12AU7 / ECC82 / ECC802S Tube SRPP Preamp Schematic - (Project)
  • 12AX7 Tube Hi-Fi Preamplifier Schematic - (Project)
  • 5687 (LED bias) Tube Hi-Fi Preamplifier Schematic - (Project)

Tube RIAA Phono Hi-Fi Preamplifiers

  • 12AX7 / 12AT7 Tube RIAA Phono Preamp Schematic - (Project)

Tube Amplifiers

2A3 - directly heated power triode

  • SET 2A3 Tube Amplifier Schematic (EF86 input) - [3.5 Watts, SET, class-A]
  • SET 2A3 Tube Amp Schematic by Loftin-White (6SL7 SRPP input) - [3.5 Watts, SET, class-A]

300B - directly heated power triode

  • SET 300B Tube Amplifier Schematic (6SN7 driver) - [8 Watts, SET, class-A] - (Photographs)
  • Parallel PP 300B Tube Mono Block Amplifier Schematic - [25 Watts, PP, class-A] - (External Link)
  • DIY 300B Single-Ended-Triode (SET) Hi-Fi Amplifier - [8 Watts, SET, class-A] - (Project) NEW

EL84, 6BQ5 - power pentode

  • SE EL84 Tube Amplifier Schematic by Mullard (EF86 input) - [3 Watts, SE, class-A]
  • SIPP 6BQ5 Tube Mono Block Amplifier (6C4 input) - [6 Watts, SIPP, class-A] - (Technical Paper)
  • SIPP EL84 (6BQ5) Tube Stereo Amp Schematic (ECC802S SRPP input) - [12 Watts, SIPP, class-A, UL] - (Project)
  • SIPP EL84 (6BQ5) Tube Stereo Amp Schematic (5751 SRPP input) - [5 Watts, SIPP, class-A, UL] - (Project) UPDATED
  • SIPP EL84 (6BQ5) Tube Mono Block Amp Schematic - [5.8 Watts, SIPP, class-A, UL] - (Project)
  • PP EL84 Tube Amplifier Schematic (ECC83 input) - [15 Watts, PP, class-AB1]
  • PP EL84 Tube Amp Schematic with Dynaco A-410 (12AX7 or 6SL7 input) - [12 Watts, PP, class-AB1]

Airmail 3 6 60 Amplifier

6V6 - beam power pentode

Airmail 3 6 60 Amp Adapter

  • SE-UL 6V6 Tube Stereo Amplifier Schematic (6SN7 input) - [4.5 Watts, SE, UL, class-A] - (Photographs) NEW
  • SE 6V6 Tube Amplifier Schematic (ECC83 input) - [4.5 Watts, SE, class-A]
  • Cathode Follower 6V6 Tube Mono Block Amp Schematic (6SJ7 input) - [4.5 Watts, CF, class-A] - (Technical Paper)
  • PP 6V6 Tube Stereo Amplifier Schematic (6SL7 input) - [12 Watts, PP, class-AB1] - (Photographs)
  • PP 6V6 Tube Amp Schematic with Dynaco A-410 (12AX7 or 6SL7 input) - [12 Watts, PP, class-AB1]

EL34, 6CA7 - power pentode

  • SE EL34 Tube Amplifier Schematic (EF86 input) - [8 Watts, SE, class-A, Pentode]
  • SE EL34, 6CA7 Tube Stereo Amplifier Schematic (6N1P input) - [4 Watts, SE, class-A, Triode or UL] - (Project)
  • SIPP EL34, 6CA7 Tube Mono Block Amp Schematic (5751 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Kit)
  • SIPP EL34, 6CA7 Tube Mono Block Amp Schematic (12SL7 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Project)
  • PP EL34 Tube Amp Schematic by Mullard with Dynaco A420 (EF86, 6CG7 input) - [50 Watts, PP, Class-AB1]

6L6, 5881, KT66, 7027 - beam power pentode

Airmail
  • SE 6L6, 5881 Tube Stereo Amplifier Schematic (6SJ7 input) - [8 Watts, SE, class-A, Pentode] - (Project)
  • SE 6L6, 6CA7 Tube Stereo Amplifier Schematic (6N1P input) - [4 Watts, SE, class-A, Triode or UL] - (Project)
  • SIPP 6L6, 5881, KT66 Tube Mono Block Amp Schematic (5751 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Kit)
  • SIPP 6L6, 5881, KT66 Tube Mono Block Amp Schematic (12SL7 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Project)

KT77 - beam tetrode

  • SIPP KT77 (class-A) Tube Stereo Amp Schematic (6SL7 SRPP input) - [25 Watts, SIPP, class-A, UL] - (Project)
  • SIPP KT77 Tube Mono Block Amp Schematic (5751 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Kit)
  • SIPP KT77 Tube Mono Block Amp Schematic (12SL7 SRPP input) - [15 Watts, SIPP, class-A, UL] - (Project)

6550, KT88, KT90 - beam tetrode

Airmail 3 6 60 amps
  • SE 6550 Tube Mono Block Amplifier Schematic (12DW7 input) - [7 Watts, SE, class-A] - (Photographs)
  • SE KT88 Tube Amplifier Schematic (6N1P input) - [5 Watts, SE, class-A, UL] - (Photographs)
  • SE KT88 Tube Amplifier Schematic (12AX7 SRPP input) by Jean Hiraga - [6 Watts, SE, class-A]
  • SE 6550 / KT88 Tube Stereo Amplifier Schematic (6N1P input) - [4 Watts, SE, class-A, Triode or UL] - (Project)
  • SIPP 6550, KT88, KT90 Tube Mono Block Amp Schematic (5751 SRPP input) - [25 Watts, SIPP, class-A, UL] - (Kit)
  • SIPP 6550, KT88, KT90 Tube Mono Block Amp Schematic (12SL7 SRPP input) - [25 Watts, SIPP, class-A, UL] - (Project)

KT120 - pentode

  • SIPP KT120 Tube Mono Block Amp Schematic (12SL7 SRPP input) - [45 Watts, SIPP, class-A, UL] - (Photographs) NEW

Compactron Tubes

  • SE 6T9 Tube Stereo Amplifier Schematic - [4 Watts, PP, Class-A] - (Project)
  • SE 6T9 Tube Stereo Amplifier Schematic - [4 Watts, PP, Class-A, Ultra-Linear] - (External Link)
  • PP 6T9 Tube Stereo Amplifier Schematic - [10 Watts, PP, Class-AB1] - (Project)

Legend: PP = Push-Pull, SE = Single-Ended, SET = Single-Ended Triode, SIPP = Self-Inverting Push-Pull, UL = Ultra-Linear

DIY Audio Schematics

Solid-State Amplifiers

  • Jean Hiraga's 'Le Monstre' Amplifier Schematic - [8 Watts, PP, class-A] - (Project)
  • Jean Hiraga's 'Super Class-A 30W Amplifier' Schematic - [30 Watts, PP, class-A] - (Project)
  • SE 2SK1058 MOSFET Amplifier Schematic - [4 Watts, SE, class-A] - (Project)
  • SE 2SK2221 MOSFET Amplifier Schematic - [4 Watts, SE, class-A] - (Project)

Solid-State RIAA Phono Preamplifiers

  • Boozhound Laboratories JFET RIAA Phono Preamp Schematic - [MM] - (Project)
  • Le Pacific JFET RIAA Phono Preamp Schematic - [MM, MC] - (Project)

DIY Headphone Amplifiers

  • SIPP 6DJ8 (ECC88) Tube Headphone Amplifier Schematic - [100 mW, SIPP, class-A] - (Project)
  • 12AU7 (ECC82) Tube / IRF510 MOSFET Headphone Amp Schematic - [tube hybrid, SE, class-A] - (Project)
  • 12AU7 (ECC82) Tube / IRF612 MOSFET Headphone Amp Schematic - [tube hybrid, SE, class-A] - (Project)
  • IRF610 MOSFET Headphone Amplifier Schematic - [SE, class-A] - (Project)
  • CMoy / Grado RA1 Headphone Amplifier Schematic - [class-AB] - (Project)

IC (Integrated Circuit) Amplifiers

Airmail 3 6 60 Amp Manual

  • Gobo LM1875 Stereo Amplifier Schematic - [15 Watts, class-AB] - (Kit) NEW
  • TDA2050 IC Hi-Fi Amplifier Schematic - [25 Watts, class-AB] - (Project)
  • LM3875 IC Hi-Fi Amplifier Schematic - [50 Watts, class-AB] - (Project)
  • LM3886 IC Hi-Fi Amplifier Schematic - [60 Watts, class-AB] - (Project)

Hi-Fi Audio Schematics

Airmail 3 6 60 Amps

Tube Amplifiers

  • Dynaco Dynakit Stereo 35 (ST35) Tube Amplifier Schematic - [17.5 Watts, PP, class-AB]
  • Dynaco Dynakit Stereo 70 (ST70) Tube Amplifier Schematic - [35 Watts, PP, class-AB]
  • Dynaco Dynakit Mark III Tube Amplifier Schematic - [60 Watts, PP, class-AB] NEW
  • Dynaco Dynakit Mark IV Tube Amplifier Schematic - [40 Watts, PP, class-AB] NEW

Airmail 3 6 60 Amp

Headphone Amplifiers

  • Grado RA1 Headphone Amplifier Schematic - [class-AB] - (External Link)
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