Elecraft T1 Assembly Manual - Manual (Page 28)

28
Tune Mode Tests
Put your T1 in Normal mode by tapping PWR/TUNE, then while the yellow LED is flashing, tap
BYP/INFO until you see the green LED on steady. It will stay on for about two seconds then go off.
Connect an antenna to your T1 (see page 9 of your Owner’s Manual for antenna recommendations).
Set your transmitter’s power output to a safe level for auto-tuning (normally 2 to 5 watts). Do not use
full power unless you’re sure your transmitter is protected against high SWR. If you are not sure, use
no more than 1/2 of its maximum power output during tuning.
Start an auto-tune operation by holding PWR/TUNE until the green LED is on, then transmit within
three seconds. You should hear the relays operate and the LEDs flash as described under Autotuning and
SWR Display on page 6 of your Owner’s Manual.
Troubleshooting
i
Observe ESD precautions while handling the tuner PC boards with the MCU installed.
Touch an unpainted ground frequently or wear a wrist strap grounded through a 1 megohm resistor.
Use an anti-static pad if you have one.
If your tuner fails any of the performance tests, remove the battery, disassemble your tuner and do a very
careful inspection. Look especially for the following:
 Missed or cold solder joints or solder bridges on either board. Use a magnifier to inspect each
joint carefully.
 Diodes with the band at the correct end. The black bands on D1 and D2 on the main PC board
must be at the end of the diodes closest to BNC connector J2 (See Figure 2). On the control
board, D2 must be oriented so the black band is on the end closest to S2, and D1 must be oriented
so the black band is on the end closest to R14 (See Figure 12).
 LEDs installed correctly. The LEDs will not light unless they were installed with the correct
polarity. Use the diode check function on your DMM to ensure they are installed correctly as
described on page 22.
 Check the toroids for properly-tinned leads. If your leads were not carefully tinned, they may
appear to be soldered but may not make electrical contact with the solder pads.
 Check the value of each part installed against the assembly procedure or schematic diagram.
Additional troubleshooting information and a complete schematic diagram is included in your Owner’s
Manual.