Low Output Help

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jpet4387
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Re: Low Output Help

Post by jpet4387 »

Well I went thru and did the highlighter test(twice) and only found a miss labelling of V2 and V3 on the schematic. Confirmed all cap and resister values. Revamped the grounding.
FINDINGS...no change.
Suggestions on where to go next before I chuck it in the garbage can(lol)...
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Bieworm
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Re: Low Output Help

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The problem probably is narrowed down to the PI, power section or the output section. Since both channels have the same result...

Could you post sound clips to see if it sounds at least normal? How many guitars and cables did you try?
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Re: Low Output Help

Post by JMPGuitars »

Post a new / fully completed voltage chart along with a sound sample of your amp.

Inspect your amp very closely for frayed wires or anything that might be grounding out that shouldn't be.

EDIT: Please also post clearer updated photos of your build.

Thanks,
Josh
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jpet4387
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Re: Low Output Help

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I will do all the above . It may be a couple days before I get it done. Got some other things to do .
Thanks again to all...
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jpet4387
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Re: Low Output Help

Post by jpet4387 »

Here are the items you requested. I hope they are satisfactory.
The amps volume is at best around 90 db per my decibel meter. The sound clip is a les paul with the amp wide open.
today when I turned it on to record the clip I had no output (first time for that) I now may have a tube or a socket that is bad. Got it to work by chopsticking. Geeeee!
Thanks
John
PS. I will get the grounds off the transformer screws but I need to make a trip to the hardware store first.
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Bieworm
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Re: Low Output Help

Post by Bieworm »

Your components are hardly soldered to the lugs. Thats a severe problem. On some photos it even looks like some resistors and caps are not soldered at all..
And those caps.. I used them before.. really no good. I removed all of those for good ones. I use RS components right now.
The heater wiring is not ideal either. Lots of signal wires touching them.. possible hum inducers...
You should really read Josh’s links in his signature. Soldering techniques.. you'll benefit from this a lot!
Look at how my heater wirings are done. I'm no expert, but hey.. this works very well.
20201124_052103.jpg
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coolidgeamps
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Re: Low Output Help

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What Bieworm said.

Image
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crgfrench
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Re: Low Output Help

Post by crgfrench »

Jpet, maybe we can help you improve that soldering -- tell us about your technique:
1) what iron are you using?
2) what temperature do you keep it at?
3) how long are you applying the iron to the joint usually?
4) what solder do you use?
5) can you describe the technique specifically?

I would recommend you read this primer:
https://mightyohm.com/files/soldercomic ... mic_EN.pdf

I would also recommend you use a eutectic solder like 63/37 rather than 60/40 -- you will have much less chance of cold solder joints that way.

I like to keep my Hakko at 750 degrees F and only heat components for a second or so to flow the joint. I also always use heatsink clip when soldering passive component leads.

Good luck!
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Re: Low Output Help

Post by Bieworm »

I suspect those fork turrets are not letten the solder stick/flow on them. Have had turrets like that too. It's sooooo frustrating!!! You apply so much heat, for tens of seconds and still they don't flow. That's why I used gold plated ones on my last build. And those caps are seriously fragile. If you pull too hard the wires come loose. On the build with those turrets and caps I threw away that board and started all over...
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jpet4387
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Re: Low Output Help

Post by jpet4387 »

Thanks for the input. This build was my first experience with a turret board. It has not been a pleasant one. I had watched the videos on you tube that Josh mentions. Did this months ago.
I used Kester 60/40,iron on 750 to 800,even wiped the turrets down with alcohol and still fought to get the solder to take. I will agree that the solder job looks like a first grader did it on some of the turrets,but when the parts stuck all was good. I had considered getting a different board but at this point I am trying to deal with the items supplied with this kit and get it functioning. It has been a learning experience all the way around.
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Re: Low Output Help

Post by JMPGuitars »

jpet4387 wrote:
Wed 11/25/20 6:21 am
Thanks for the input. This build was my first experience with a turret board. It has not been a pleasant one. I had watched the videos on you tube that Josh mentions. Did this months ago.
I used Kester 60/40,iron on 750 to 800,even wiped the turrets down with alcohol and still fought to get the solder to take. I will agree that the solder job looks like a first grader did it on some of the turrets,but when the parts stuck all was good. I had considered getting a different board but at this point I am trying to deal with the items supplied with this kit and get it functioning. It has been a learning experience all the way around.
get some kester no clean 63/37 solder instead.

Make sure you're using a chisel tip on your iron (no pencil tips).

Experiment on a safe turret to see where holding the iron works the best. You need the base and the fork to heat up, so heat the base. Use a drop of solder as a bridge for heat transfer. If you're not getting enough heat across, you might need more solder to make that bridge. If the turret heats up enough, and it was clean, you should be able to make a bond.

If you're still having trouble making that bond, get some flux. Dab the turret with the flux, melt it, and try the above again.

Thanks,
Josh
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Re: Low Output Help

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Expanding on Josh's suggestions...PUNCH THE TURRENT IN THE FACE with HEAT fast. Here's my method, before each soldering operation I clean my tip both on a damp sponge and scrub it in some brass fuzz. It should be shiny. Then apply some fresh solder to the tip, more than a modest amount when soldering a turret. This dab of wet solder is the conduit which heat transfers through from the tip of the iron to the turret. The bigger the dab the faster the heat will transfer but don't over do it and make a mess. Immediately upon applying the tip to the turret dab a little more fresh solder to get some flux on the turret. It will heat up fast at 800 you won't have a problem getting the solder to flow. Punch it in the face with heat fast, solder, then remove fast don't linger with the tip on the turret.

HEAT SINK components. Digikey sells small flat tipped (not toothed) alligator clips like 10 for $6 which are perfect heat sinks. They are so small they don't get in the way of soldering. Clip them onto the component leads to keep the heat away from the component body. When you hit a turret with that much heat that fast you want to protect the component and avoid cooking it.
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Re: Low Output Help

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coolidgeamps wrote:
Wed 11/25/20 1:45 pm
Then apply some fresh solder to the tip, more than a modest amount when soldering a turret.
I agree with everything except that part. I only apply solder when the tip is touching the turret. The process is still only a few seconds, but none of the flux in the solder is wasted.

It doesn't necessarily hurt to do it your way, but there are two issues: 1. is that flux is wasted and burned off; and 2. is that it opens the possibility to drop the solder somewhere you don't want it to land.

In your case it's not as big of a deal with all the blue tape everywhere, but personally I think I would drop that solder blob on a $10 capacitor. lol

Thanks,
Josh
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Re: Low Output Help

Post by crgfrench »

JMPGuitars wrote:
Wed 11/25/20 1:54 pm
it opens the possibility to drop the solder somewhere you don't want it to land.
This actually ruined a Quaverato build I attempted once, right at the very last step of the entire build.
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Re: Low Output Help

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crgfrench wrote:
Wed 11/25/20 2:19 pm
JMPGuitars wrote:
Wed 11/25/20 1:54 pm
it opens the possibility to drop the solder somewhere you don't want it to land.
This actually ruined a Quaverato build I attempted once, right at the very last step of the entire build.
The devil's in the detail 😄😄😄
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Re: Low Output Help

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JMPGuitars wrote:
Wed 11/25/20 1:54 pm
coolidgeamps wrote:
Wed 11/25/20 1:45 pm
Then apply some fresh solder to the tip, more than a modest amount when soldering a turret.
I agree with everything except that part. I only apply solder when the tip is touching the turret. The process is still only a few seconds, but none of the flux in the solder is wasted.

It doesn't necessarily hurt to do it your way, but there are two issues: 1. is that flux is wasted and burned off; and 2. is that it opens the possibility to drop the solder somewhere you don't want it to land.

In your case it's not as big of a deal with all the blue tape everywhere, but personally I think I would drop that solder blob on a $10 capacitor. lol

Thanks,
Josh
That initial tinning of an 800 degree cleaned tip can be explosive with flux and solder spattering in all directions. So I do that in a safe zone away from the turret. Also helps avoid eating a face full of smoke and fumes. But its whatever technique works for people. A good solid solder joint however achieved is good to go!

I also double solder turrets. On the first operation I let the solder suck down into the turret hole. Let it cool a bit then hit it again with a finishing crown of solder.
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Re: Low Output Help

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coolidgeamps wrote:
Wed 11/25/20 9:24 pm
That initial tinning of an 800 degree cleaned tip can be explosive with flux and solder spattering in all directions. So I do that in a safe zone away from the turret. Also helps avoid eating a face full of smoke and fumes. But its whatever technique works for people. A good solid solder joint however achieved is good to go!

I also double solder turrets. On the first operation I let the solder suck down into the turret hole. Let it cool a bit then hit it again with a finishing crown of solder.
lol, that's because you haven't tried the no clean solder yet. ;)

I never fill turret holes unless I'm using them, which is relatively rare. I generally try to keep all my turret connections external for the additional mechanical connection support.
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Re: Low Output Help

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JMPGuitars wrote:
Thu 11/26/20 8:08 am
coolidgeamps wrote:
Wed 11/25/20 9:24 pm
That initial tinning of an 800 degree cleaned tip can be explosive with flux and solder spattering in all directions. So I do that in a safe zone away from the turret. Also helps avoid eating a face full of smoke and fumes. But its whatever technique works for people. A good solid solder joint however achieved is good to go!

I also double solder turrets. On the first operation I let the solder suck down into the turret hole. Let it cool a bit then hit it again with a finishing crown of solder.
lol, that's because you haven't tried the no clean solder yet. ;)

I never fill turret holes unless I'm using them, which is relatively rare. I generally try to keep all my turret connections external for the additional mechanical connection support.
You have set the bar high for this no clean solder it better **** tiffany cuff links! lol Hey I'm always open to new methods and learning new tricks. If you don't fill the turret holes tone will escape. But seriously how do you wrap component leads around turret shanks without imparting pull tension on the component body?
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Re: Low Output Help

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coolidgeamps wrote:
Thu 11/26/20 11:15 am
You have set the bar high for this no clean solder it better **** tiffany cuff links! lol Hey I'm always open to new methods and learning new tricks. If you don't fill the turret holes tone will escape. But seriously how do you wrap component leads around turret shanks without imparting pull tension on the component body?
Lol! Get back here, tone!

Components can handle a little tension, but obviously you should still take care in the process.

These are my 3 most used tools:
josh-tools.jpg

I bend the leads ahead of time with the pliers on the left. Then I use the angle pliers to carefully complete the j-hook, then I snip the leads with the flush cutter.

Sometimes I use one of these measurement lead bending tools (I have 4 different sizes of these):
lead measure guide thing.jpg

More often than not though I just eyeball it, pre-bend one side, then place and bend the other side. Obviously that doesn't work as well for tighter spots, so they get premeasured.

Thanks,
Josh
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Re: Low Output Help

Post by coolidgeamps »

@jmpguitars I have a pair of those rounded needle nose in my Digikey shopping cart I want to try them. Sometimes I want to twist a nice circle or J.

I use very long slim needle nose pliers a lot because my man sized bear paws are too large for working inside a chassis. The flat spring steel spring half broke during this last build so I'm buying a new higher quality pair with the coil spring.

Centering components of course easier for me since I have silk screened the exact size of the component body onto the board. Because I solder components into the turret holes clipping the leads to the right length is super easy. Position the component across the top of the turrets. Use the outer edge of the turret top as a cutting guide, kiss my cutters up next to it and clip. That gives me about .1 inch to bend into an L. Hook that end into the turret and repeat clipping the other end to the outside edge of the turret top easy peasy perfectly centered. Also lets me avoid putting a pull tension on the lead. The tiny flat tipped alligator clips I use to heat sink have a dual use in also keeping the component positioned (weighted down) during soldering.

It's funny the little techniques you come up with. I have long been irritated with soldering ground wires to the ground buss across the pots. A big solder glob mess. This build I soldered some eye loops that hang down from the buss wire to attach all those grounds. But how to solder that to the bus wire straight. Solution, took some buss wire, bent one end into a hook, twisted a #8 lock nut to the other end as a weight, hung my eye loop onto the buss wire with this gadget weighting it down straight and level!
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