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 Post subject: Re: very VERY Brown rca not playing audio
PostPosted: Oct Wed 06, 2021 10:29 am 
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well after a bit of back and forth making sure im touching the right contacts (shining bright light through the board helps a lot) i found that the two resistors in between the volume and the transistor both read basically nothing just shows 00002 on the meter. i checked a couple other near by resistors and they were reading and were more or less in the ball park of what they needed to be.
while i cant imagine 2 resistors both being bad (a 15 and a 5.6k)i will just get some in the next order of parts since their cheap and when i get them i will just tack them on the back side and flip the power on and see if it works...

EDIT: and if i'm looking at it correctly i think the 15 comes off the volume pot and goes to the transistor which then goes through the 5.6 and then goes to the speaker. so if the 15 is bad then neither the transistor or the 5.6k resistor would work correctly.....


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 Post subject: Re: very VERY Brown rca not playing audio
PostPosted: Oct Mon 11, 2021 6:47 am 
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okay now im really getting confused. i pulled out both them resistors and once out they both test just fine. and as soon as i put the new ones in place they become ''unreadable'' and give the same reading as the old ones. what could be causing this?


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 Post subject: Re: very VERY Brown rca not playing audio
PostPosted: Oct Mon 11, 2021 3:48 pm 
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A parallel component...

Unless you're sure there isn't another resistor, coil, etc that going to skew in circuit readings(probably at least 50% of time), always disconnect suspect part.

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 Post subject: Re: very VERY Brown rca not playing audio
PostPosted: Oct Wed 13, 2021 3:38 pm 
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Here's why the 5.6K ohm reads very low in circuit... Connects to audio output xformer, down to the B- common, back to 15 ohm & opposite end of 5.6K. Assuming 15 ohm is OK, should measure approx 15-16 ohms. In real world, higher value resistors are 99.99999% never shorted.

That 5.6K will not cause a no play even if missing. Creates a feedback path to Q3 that lessens distortion.


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Last edited by 35Z5 on Oct Thu 14, 2021 3:38 pm, edited 1 time in total.
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 Post subject: Re: very VERY Brown rca not playing audio
PostPosted: Oct Thu 14, 2021 2:57 am 
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hmmm well than that puts me in a pickle....


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