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Old 28th March 2010, 02:26 AM   #7561
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are the shorted input necessary for testing? i didn't see it anywhere in the guides, so i didn't do it.
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Old 28th March 2010, 02:29 AM   #7562
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Quote:
Originally Posted by acold7dusta View Post
are the shorted input necessary for testing? i didn't see it anywhere in the guides, so i didn't do it.
If the input is floating it might pick up mains hum and rf which might confuse readings.
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Old 28th March 2010, 03:10 AM   #7563
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it won't cause damage without it though, correct?
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Old 28th March 2010, 04:15 AM   #7564
ichiban is offline ichiban  United States
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Quote:
Originally Posted by acold7dusta View Post
it won't cause damage without it though, correct?
True.
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Old 28th March 2010, 07:11 PM   #7565
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Originally Posted by acold7dusta View Post
pots read 0.3R, the fuse is fine, and my 0.47R resistor reads 0.5R. not sure why my other resistors are all now out of wack though...
Most, not all, DVMs have a small offset at very low resistance ranges... check to see if you get 0.00 with the leads connected or not.

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Old 28th March 2010, 08:48 PM   #7566
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Originally Posted by bear View Post
Most, not all, DVMs have a small offset at very low resistance ranges... check to see if you get 0.00 with the leads connected or not.

_-_-bear
I get 0.2 ohms when they're connected directly. The 0.47R reads 0.7ohms uncorrected, and the pots read 0.3, which is 0.1 corrected
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Old 28th March 2010, 09:51 PM   #7567
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here are my resistor values that are out of wack. This is for the left channel, and the right channel is similar (as well as my other boards)

R1&R2: 8.1R, 8.5R (10R)
R5-R8: 12.3R, 15.8, 7.2, 15.8 (100R)
R15&R16: 1.6K (2.2K SERIES 4.7K)
R17&18: 130R (1K)
R19&R20: 130R (150R, NOT TOO BAD)
R21&R22: 130R, 173R (22K!)

does anyone know what is going on with my amp? my other boards read the same numbers and that's why i bought new parts and boards because they read so much off.

The resistors were all normal before they were loaded (didnt check after they were mounted though)

readings were as the amp hooked up to the PSU, but not 120V wall power
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Last edited by acold7dusta; 28th March 2010 at 09:56 PM.
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Old 28th March 2010, 09:55 PM   #7568
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You cant measure the value of a resistor once you put it in the board. It ends up being in series and parallel with other resistors. Maybe you put in a 1k resistor that goes to ground and elsewhere you put in another resistor of 100R that goes to ground and if you measure from both sides of the 1k you measure the value of a 100R in parallel with a 1k. That would be kind of simple but then you resistors in series somewhere between those two and others going to ground and it ends up a mess to measure while in circuit.
Like look at your R21 and R22. They must be parallel to a resistor that is close to 150R. Probably R19 and R20 but I am not looking at the schematic right now.
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Old 28th March 2010, 10:05 PM   #7569
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well that clears that confusion up thanks
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Old 30th March 2010, 02:47 PM   #7570
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I was looking around for caps for my F5 and came across this deal on FleaBay 200pcs 15000uf/25V Capacitor.
At about 63 cents a piece before shipping they're not a bad deal for those on a tight budget.

Regards,
Dan
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