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threshold s/450e bias
threshold s/450e bias
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Old 19th November 2019, 09:24 PM   #1
miguelnoda is offline miguelnoda  Spain
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Default threshold s/450e bias

hello I want to adjust the bias of my threshold s / 450e and I don't know at what points I should take the readings and how much they have to give me can you help me
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Old 19th November 2019, 10:12 PM   #2
UserAbuser is offline UserAbuser
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Your answer is here.
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Old 19th November 2019, 10:25 PM   #3
miguelnoda is offline miguelnoda  Spain
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I don't understand.
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Old 19th November 2019, 10:58 PM   #4
Nelson Pass is offline Nelson Pass  United States
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threshold s/450e bias
Perhaps he is living up to his name....

There will be a bias pot for each channel. You can read the voltage off
of the emitter resistors of the output transistors which I recall to be 1 ohm.

Check several of them. The S450e has 6 of those in parallel, so the
bias current with the 1 ohm resistor is 6 times the voltage you read.

.1V = .6 amps bias

You will want to be careful, as you can damage the amp or yourself
doing something like this. Make adjustments in small steps and allow
the amp to sit with the cover on for a while before re-checking.

Best advice - bribe a technician to do it for you.
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Old 20th November 2019, 11:04 PM   #5
miguelnoda is offline miguelnoda  Spain
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Take measurements from the base to the emitter and it gives me 562 mv
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Old 20th November 2019, 11:06 PM   #6
Zen Mod is offline Zen Mod  Serbia
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threshold s/450e bias
not that

measure voltage across 1R emiter resistor

check that at several of them , write here
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Old 21st November 2019, 10:31 AM   #7
miguelnoda is offline miguelnoda  Spain
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He wants me to measure the emitter of ground on the two rails in the 1ohm resistor
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Old 21st November 2019, 10:40 AM   #8
Zen Mod is offline Zen Mod  Serbia
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threshold s/450e bias
OK , if you said so

though , then we can't help
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Old 21st November 2019, 11:43 AM   #9
miguelnoda is offline miguelnoda  Spain
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Default threshold s450e

from ground to emitter measures 78.2 vol and 76.8 volts
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Old 21st November 2019, 11:52 AM   #10
coolnose is offline coolnose  Europe
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miguelnoda,

NP wants you to do the same thing ZenMod has asked for 100%...

Measurements on several resistors to confirm consistancy of measurement as to tolérance of source/emitter resistors I suppose.

The measurement you give are of no use to help you.
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