Download The Triode Board

CONTENTS
1. Features......................................................................................................... 4
2. Introduction................................................................................................... 5
2.1 What You Get....................................................................................... 5
2.2 What You’ll Need.................................................................................. 5
2.3 Choosing Configuration Options .......................................................... 5
3. Triode Amplifier Control and Protection .................................................... 6
3.1 Grid and Anode Current Metering ........................................................ 6
3.2 Meter and Surge Protection.................................................................. 6
3.3 Grid Current Protection ........................................................................ 9
3.4 Cathode Bias ...................................................................................... 10
3.5 TX/RX Switching ................................................................................ 10
3.6 24V Relay Option ............................................................................... 11
3.7 PTT Options ....................................................................................... 11
3.8 Warm-up Timer Options..................................................................... 12
3.9 RFI Protection..................................................................................... 12
4. Using Your Tubes and Meters................................................................... 12
4.1 Which Tube – or Tubes?.................................................................... 12
4.2 Choosing and Using Meters ............................................................... 13
5. Building the Triode Board ......................................................................... 15
5.1 Mounting the Board ............................................................................ 15
5.2 Board Modifications ............................................................................ 15
5.3 Assembling the Board ........................................................................ 15
5.4 Building the LED Array ....................................................................... 17
5.5 Building the HV Divider....................................................................... 17
6. Off-line Testing ........................................................................................... 19
6.1 Meters................................................................................................. 19
6.2 Cathode Bias Adjustment................................................................... 21
6.3 Control Logic and Alarm Settings ....................................................... 21
7. Interconnections......................................................................................... 24
7.1 Mains Power Control .......................................................................... 24
7.2 HV Control and Safety........................................................................ 25
7.3 CHASSIS GROUND Connection ....................................................... 25
7.4 RFI Suppression................................................................................. 25
8. Power-Up ..................................................................................................... 26
8.1 First Switch-on.................................................................................... 26
8.2 Cathode Bias Adjustment................................................................... 26
8.3 RF Testing.......................................................................................... 26
9. Updates and Product Support................................................................... 27
Schematics ................................................................................................. 28–32
Parts List........................................................................................................... 33
Appendix 1 – Higher Cathode Bias ................................................................ 37
Triode Board: AN-2
Issue 1.5 for board v2.4, January 2003
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