20 Most Recent
Questions & Answers
You're getting some feedback on the secondary transformer - most likely... Try to isolate where the pitch is coming from and see if it's harmonic. May just need to be glued down or have some leverage place against it...
on Apr 06, 2013
AKAI CT 2112
This is a typical power supply problem. Please check the B+ Power Supply that goes to the LOT (FBT). It should be 110V. If that is ok, check the voltage while increasing and decreasing brightness, sound. If there is variation, the problem is in the SMPS. Look for dry capacitors, open/high value resistors, zener diodes, transistors etc. If nothing works, please download a data-sheet of the IC and check voltages at the pins and locate the adjacent components. Even a dry capacitor in the power supply can decrease the votage at load
on Jan 25, 2011
I have an Akai Lct2662
The issue you describe is consistent with a power supply board issue. This is the board where the AC goes to.
I do not think it needs replacement, rather some defective capacitors are causing this issue.
unit up and take a look at the power supply board.You will probably see
one or more electrolytic filter capacitors that are bulged up in the
top-not perfectly flat like the others. Also, there is a flyback transformer in the TV that can cause this type of problem.
The value of these
capacitors will be different, most likely they will be somewhere
around-820 to 2200uF/25 V( or /10V sometimes)
can replace them with same values but I would recommend the voltage
rating to be higher(like 35V for an original 25V) for reliability
What happens is,these bulged top capacitors will cause a
low and unfiltered DC voltage=main board will malfunction(the relay
will keep clicking until the caps are holding enough charge to bring the
voltage up over a threshold point).
You can buy these capacitors
at any Fry's or Radioshack store or you can order them online at vendors
like "mcmelectronics.com"(look for electrolytic capacitors).
After replacing these capacitor(capacitors) most likely the normal operation will be restored.
may be also some other causes for this symptom ,like a defective T con
board ,or main board,but the bulged top capacitors are the most common
cause for this issue.
If you don't know about TV repairers, take
the TV to the nearest repairman to fix the fault for you. Also, note
that TV stores a lot of current, so wait a while before opening the TV
I hope this helps.
on Dec 05, 2010
I need to know the
If you have the original fuse, it's the number stamped on one of the end caps after the three letters denoting the fuse type. Most manufacturers also print the fuse rating on the power supply circuit board ("Caution: replace fuse only with...")
I have one of these sets in the shop now, but I haven't opened it yet. Post a reply if you can't find the fuse type and rating, and I'll let you know what my project uses.
I assume you already know fuses in TV sets don't blow by themselves, but indicate another part is shorted. Check the diodes, transistors and power ICs in the power supply before plugging the set in. If you see any bad capacitors, fix those also.
on Oct 12, 2010
Not finding what you are looking for?