(Infinity^2) writes:

I am working a a Daytek DT-1704C 17" monitor. It powers up with no
HV. I was prodding around the power supply unit and inside is a
TF341M thyristor (I looked up the datsheet). Using the diode test on
my DMM it measures 0.266V between gate and cathode both ways. Is this
normal? or can a thyristor even be tested with a DMM? If the part is
bad I suspect it is preventing some sections of the monitor from
receiving power. Any advice is appreciated. Thanks.

+ o----+-----/\/\---------+-----o Test+
| 100, 2W __|__
| _\/\_ Device Under Test - DUT
12 VDC | R2 / | (SCR or triac).
+---/\/\---o --' |
1K o |
| |
- o----------------+------+-----o Test-

Apply the 12 V. The device should be off.
Touch the gate R2 - it should turn on and stay on.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: The email address in this message header may no longer work. To
contact me, please use the Feedback Form at repairfaq.org. Thanks.