In setting bias for the hartke ha3500 amp,,where exactly do I place my probe to monitor?..............I recently changed the 2sc5200 and 2Sc1943 and repaired the eq section..amp works now but the transistors get too hot before 1min.
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HI!
Measure the voltage between Tp301 &Tp302, and adjust on SVR302 for about 20 - 25mV.
With the device switched on, repeat the setting after half an hour.
The SVR301 controls the DC level of the output.
Hifista.
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Okay,,so I measured BTW tp301 and tp302...and I got a 1.22v instead of milivolt...I turned the SVR 302...but voltage remains 1.22v and wouldn't even change..
what do I do mow?
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I don't know exactly what parts have been replaced so far, but I will describe what I would check.
First, the SVR301 is not used to adjust the base current, but to set the output DC level to zero.
So 1.22 V is a lot. If it cannot be regulated, then the Q308 transistor (2sc3200), the D303, D304 diodes, and the R319, R320 resistors should also be checked.
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Should I adjust the svr301 for any reason??
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Thanks hifistar...but my question is where do I place my meter probe to get this setup done....?
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You have to find the points TP301 and TP302 and measure between the two points.
These are the same points as the emitters of transistors Q313 and Q314.
The Voltmeter should be in the 200mV position.
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This is more detailed...
thanks Hifista....I'll try it out wen I get back ti work tomorrow...
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Hello
SVR302 1Kohm trimmer
Measure bias current at B+.
Schematics
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Thnks Mr took,,,,but do you mean while adjust the svr301 my probs should be between PNP base and ground??
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Measure current between power supply positive and power amp positive pin.
(cca 100mA)
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Okay ,then I presume I'm to put my meter in series btw rectified power + and amp + terminal ?
If not pls make it more easier to understand pls
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