Appreciate the direct "Ask Me". With reference to your post here
checks are done with the power on whereas resistance/continuity check
are performed with the power off and preferably the component out of
circuit. The VOM would do.
You posted that the fuses have not blown and therefore
you are assuming that the output transistors are not defective. Pls
confirm this by performing a check on the base to collector to emitter
of the output transistors. This page
would illustrate how to check a transistor using a VOM. The output transistor once removed from the circuit (pls mark which goes to where
laying flat with the pins/feet pointing towards you would be base,
collector and emitter. Although the real outputs if 2SA1302/2SC3281
would be larger.
Most NHT sub amps are standard design amplifiers. To my knowledge, NHT amps (but not all
uses a unique design to supply power to the output transistors. The
fuses does not tie directly to the output transistors from the +/- of
the power supply. Instead the fuse goes to several power MOSFETS
(IRF640) that regulate/control/monitor the current/voltage supplied to
the output transistors. If any of the IRF640 is blown, the output would
have no voltage even if the fuses are good.
To be more specific and to confirm the above, would appreciate if you could post/share the schematic diagram.
May I also inform you that there are posts made by other members of the community (our co-experts, I am aware that you have provided solutions yourself in some other posts
) that would be of additional help. ginko
has posted the method/manner by which you could test the transistors and other components, while bunnydawg
addressed the fuse not blowing. welcomejee
has posted with an amp schematics of an NHT Subtwoi.There were however and I would expect
more posts that are too general/generic to be of any real use to you. I
would leave it to your discretion to filter through the flood of
As a site policy, once you rejected a solution or give it a "Thanks for Trying
", that particular post/expert would no longer be viewable. For your benefit, may I suggest that you copy and paste the "workable solutions
" to a document that you would have a record of previous or no longer viewable postings.