I bought a hafler dh 200 last week to match my other dh 200 I received from my brother, decided to run another set of polks..
I decided to open it up and check bias and found it had wrong transistors (not matched) still had original electrolytic caps also R39 was removed and right channel rca jack was grounded to wire in between big caps.
So I changed out all the transistors with new ones and new caps and removed ground wire..
My right channel biased perfect at 250 ma but my left channel is only showing 6 ma and with my meter set to dc of course.
So I went through the board and hit all of it wit fresh solder checked all the wires from the mosfets..
checked again and now I don’t have 120 volts across c-16 and c-17.
Could my switch be bad?
Also, I did hook it up to some garage speakers when I brought it home and both channels worked but ran a lot warmer than my other DH 200 ...
I am a novice at best any advice/ help is greatly appreciated..
I decided to open it up and check bias and found it had wrong transistors (not matched) still had original electrolytic caps also R39 was removed and right channel rca jack was grounded to wire in between big caps.
So I changed out all the transistors with new ones and new caps and removed ground wire..
My right channel biased perfect at 250 ma but my left channel is only showing 6 ma and with my meter set to dc of course.
So I went through the board and hit all of it wit fresh solder checked all the wires from the mosfets..
checked again and now I don’t have 120 volts across c-16 and c-17.
Could my switch be bad?
Also, I did hook it up to some garage speakers when I brought it home and both channels worked but ran a lot warmer than my other DH 200 ...
I am a novice at best any advice/ help is greatly appreciated..
I just want to tell you that across +/- c-16 and c-17 it need to be 60VDC not 120V.
The R39 need to be 0.5R 1/2W and at the Right CH the RCA Ground need to connect to the ground with 2.2R 1/2W (R45) BUT it will be ok if R39, R45 will be 0R
also i know that Bias need to calibrate each MosFet 100ma not more.
The R39 need to be 0.5R 1/2W and at the Right CH the RCA Ground need to connect to the ground with 2.2R 1/2W (R45) BUT it will be ok if R39, R45 will be 0R
also i know that Bias need to calibrate each MosFet 100ma not more.
My schematic says 2.2 1/2 watt resistor on R39,
I believe I’m calling right side of amp left side; I replaced R 45 with 2.2 ohm
I found the screws on the big caps not tight so I’ll check voltages again..
I believe I’m calling right side of amp left side; I replaced R 45 with 2.2 ohm
I found the screws on the big caps not tight so I’ll check voltages again..
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