fired up this morning and low voltage on the filter caps?

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martin manning
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Re: fired up this morning and low voltage on the filter caps?

Post by martin manning »

Replacing the balance resistors is a start, but I don't understand why nothing seems to happen until it's switched off standby.
sluckey
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Re: fired up this morning and low voltage on the filter caps?

Post by sluckey »

He followed the Ceriatone layout and the STBY switch is between the rectifier diodes and the reservoir cap stack.
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

ok so in standby mode with the 60 watt limiter bulb i am getting.....

bias -50vdc on one and -37vdc on the other lug of the pot

on the standby switch one side seeing 392vdc and the other 0v

the relay is at 16.32v going in and 11.88v feeding the relays.
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

also when in standby and checking voltages ,the sixty watt bulb was very dim.
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martin manning
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Re: fired up this morning and low voltage on the filter caps?

Post by martin manning »

The standby has been relocated to after the reservoir caps now or no, and that's in standby? Can you switch it to play and does the limiter stay dim?
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

is it possible that the choke is wired backwards? as this is my first build i am learning.
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drew
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Re: fired up this morning and low voltage on the filter caps?

Post by drew »

The light bulb limiter is just a quick check to see if you have a short circuit. When you turn the power on, the bulb should be bright momentarily, then go dim right away. If that’s what you’re seeing, go ahead and plug the amp straight in to your electrical outlet and proceed with voltage checks.
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pompeiisneaks
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Re: fired up this morning and low voltage on the filter caps?

Post by pompeiisneaks »

skyripper2 wrote: Fri Jun 29, 2018 8:05 pm is it possible that the choke is wired backwards? as this is my first build i am learning.
This is not possible, chokes don't have a direction.

~Phil
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

martin manning wrote: Fri Jun 29, 2018 8:01 pm The standby has been relocated to after the reservoir caps now or no, and that's in standby? Can you switch it to play and does the limiter stay dim?
not sure what you are asking. if i take it out of standby the light is bright and stays bright and there does not seem to have very much voltage on the lug of the standby switch . one side see's lots the other does not. i believe my standby is before the caps.
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martin manning
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Re: fired up this morning and low voltage on the filter caps?

Post by martin manning »

That says there is a lot of current draw after the standby. Have you replaced the 220Ω resistors with either 220k or 270k?
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pompeiisneaks
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Re: fired up this morning and low voltage on the filter caps?

Post by pompeiisneaks »

martin manning wrote: Fri Jun 29, 2018 8:17 pm That says there is a lot of current draw after the standby. Have you replaced the 220Ω resistors with either 220k or 270k?
This

DO. NOT. POWER. ON. AGAIN. UNTIL. YOU. REPLACE. THESE.

:D

~Phil
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

pompeiisneaks wrote: Fri Jun 29, 2018 8:07 pm
skyripper2 wrote: Fri Jun 29, 2018 8:05 pm is it possible that the choke is wired backwards? as this is my first build i am learning.
This is not possible, chokes don't have a direction.

~Phil
Thanks Phil i figured as much but had to ask.
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

well off to see my dentist .
this will have to wait . and again thanks for trying to help me get her going.
eat,sleep,build amp.........
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

pompeiisneaks wrote: Fri Jun 29, 2018 8:18 pm
martin manning wrote: Fri Jun 29, 2018 8:17 pm That says there is a lot of current draw after the standby. Have you replaced the 220Ω resistors with either 220k or 270k?
This

DO. NOT. POWER. ON. AGAIN. UNTIL. YOU. REPLACE. THESE.

:D

~Phil

thanks Phil i won't
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skyripper2
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Re: fired up this morning and low voltage on the filter caps?

Post by skyripper2 »

well i survived the dentist.
so after seeing that i used the wrong resistors on my filter caps . I figured i had better check my main board and everything else and see if i used wrong values elsewhere. so i took the layout and started marking things using windows paint!!!!! green dots (good) and red dots (wrong needs changing) to simplify things . I found a local electronics tech who says he's got what i need so this next week i can go get the right values from him and try again. opening the drawing up in windows paint made my life a lot easier .
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