led don't light and no voltage readings on any terminal

leviathan · 1938

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Offline leviathan

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Hi.
I just finished building the crack and I am having an issue where the led do not light (one lit when i first plugged it in but has since gone out) and all voltage checks come up as 0. The resistance checks are perfect though
« Last Edit: August 02, 2018, 07:19:51 PM by leviathan »



Offline adydula

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Reply #1 on: August 03, 2018, 03:56:12 AM
All voltage checks are "0"....

Be careful probing around, but have you checked the fuse and make sure its not blown?
If so you may have a short to ground?

I would recheck all the wiring for the power supply, input from 110VAC to the switch, power transformer etc...

Alex



Offline leviathan

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Reply #2 on: August 03, 2018, 05:58:50 AM
All voltage checks are "0"....

Be careful probing around, but have you checked the fuse and make sure its not blown?
If so you may have a short to ground?

I would recheck all the wiring for the power supply, input from 110VAC to the switch, power transformer etc...

Alex
the fuse has not blown, since I started the thread have also checked between the 11-16 to 17-20 tabs and those seem to have voltage. its just the 1-5 and 6-7 that dont.



Offline adydula

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Reply #3 on: August 03, 2018, 08:23:12 AM
Post a few pictures of the assembly...



Offline Paul Birkeland

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Reply #4 on: August 03, 2018, 09:06:42 AM
0v AC or DC?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline leviathan

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Reply #5 on: August 03, 2018, 10:08:20 AM
0v AC or DC?
DC
Post a few pictures of the assembly...
Ok I’ll upload some

Also one thing I did notice after looking very closely is that my small ceramic resistor (5 watt 270ohms) is cracked. Is that an indication of damage and if so where do I get a replacement?
Thanks



Offline leviathan

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Reply #6 on: August 03, 2018, 01:11:06 PM
here are the images the resistor was just slightly cracked but after i touched it it pretty much fell apart
https://imgur.com/a/x6E9udl
« Last Edit: August 05, 2018, 06:16:06 PM by leviathan »



Offline adydula

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Reply #7 on: August 05, 2018, 08:45:46 AM
Hello, I am trying not to be real critical but many of the solder joints look like they need some work.
Several of your leads are excessively long some seem close to shorting stuff out?

Some of those leads should be clipped shorter IMO.

The focus in you pix is not the best to really see them best.

I notice some melted wiring as well.

I would take some more detailed pix and try to focus in a smaller area so we can better see whats there.

I will let the experts speak to the resistor falling apart. Usually when a resistor gets really hot, due to a short it may do this.
Which would indicate you have some stuff touching other stuff improperly.

Alex




Offline leviathan

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Reply #8 on: August 05, 2018, 06:15:49 PM
Hello, I am trying not to be real critical but many of the solder joints look like they need some work.
Several of your leads are excessively long some seem close to shorting stuff out?

Some of those leads should be clipped shorter IMO.

The focus in you pix is not the best to really see them best.

I notice some melted wiring as well.

I would take some more detailed pix and try to focus in a smaller area so we can better see whats there.

I will let the experts speak to the resistor falling apart. Usually when a resistor gets really hot, due to a short it may do this.
Which would indicate you have some stuff touching other stuff improperly.

Alex
Yes I am still pretty new to soldering and my first non pcb based project, I have since replaced the resistor and cleaned up some of the solder joints and slightly melted wire (that was a bit of carelessness while re soldering). I used my voltmeter to test the led that wasn't working and determined it was dead and have ordered a replacement. Oh and I believe mis-wiring 15 and 18 caused the resistor to heat excessively.   
« Last Edit: August 06, 2018, 08:16:20 AM by leviathan »



Offline Paul Birkeland

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Reply #9 on: August 06, 2018, 05:28:08 AM
This amp is miles off from what's shown in the manual.  We have a lot of specific instructions for problem areas, and these instructions have not been followed.  You have blown the first 270 ohm 5W resistor in the power supply, so it's not a matter of moving a wire or reheating a joint to get this amp working.

Did this amp pass its resistance checks?  Almost always, the amp will fail the resistance checks prior to roasting those power supply resistors.

My strongest suggestion here would be to purchase a replacement set of hardware and electronics from us and just take everything off that plate except the power transformer, then start over.  If I had this amp in for repair, this would be my course of action to effect repairs.

While you're waiting for the parts order, you might send us photos of the tools you have for the build.  Often times I've found that builders are struggling not necessarily because of a lack of skill, but because the tools they are using are limiting their capabilities.
« Last Edit: August 06, 2018, 05:31:20 AM by Caucasian Blackplate »

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


4krow

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Reply #10 on: August 06, 2018, 06:09:20 AM
  I have to second the part about tools being used here. My solder joints were embarrassingly bad using a 25 watt pencil. The solder was not much good either. Then I tried my first soldering station, and couldn't have been more impressed. Better solder helped too. Using the right tip on the pencil is also worth discovering. Once you get this set up and use it (the correct soldering tool) you will be impressed as well. Don't lose hope, it gets better.



Offline leviathan

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Reply #11 on: August 06, 2018, 08:13:51 AM
This amp is miles off from what's shown in the manual.  We have a lot of specific instructions for problem areas, and these instructions have not been followed.  You have blown the first 270 ohm 5W resistor in the power supply, so it's not a matter of moving a wire or reheating a joint to get this amp working.

Did this amp pass its resistance checks?  Almost always, the amp will fail the resistance checks prior to roasting those power supply resistors.

My strongest suggestion here would be to purchase a replacement set of hardware and electronics from us and just take everything off that plate except the power transformer, then start over.  If I had this amp in for repair, this would be my course of action to effect repairs.

While you're waiting for the parts order, you might send us photos of the tools you have for the build.  Often times I've found that builders are struggling not necessarily because of a lack of skill, but because the tools they are using are limiting their capabilities.
It passed the resistance tests before I burned out the resistor and has since passed the resistance and voltage test after I replaced the resistor and fixed the 15 to 18 wire.  Do you have a link for the replacement set of electronics? The parts section on the website only shows the leds (which I have already bought) and rocker switch. And I am going to invest in a better set of tips and soldering station for changing the parts out.  I also realize I may have gotten a little overeager and rushed through the assembly, definitely going to take a bit more time with the new parts
« Last Edit: August 06, 2018, 08:31:23 AM by leviathan »



Offline Paul Birkeland

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Reply #12 on: August 06, 2018, 08:58:01 AM
You'll have to e-mail replacementparts(at)bottlehead(dot)com and reference this thread.  I forgot to include the wire bag in there, which should also be on the list.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man