Mission 5E3 Kit... - Page 6

JohnnyCrash · June 27th, 2008, 01:42 AM

I believe another Volume mod is to make the Volumes independent, instead of interactive.

sjhusting · June 27th, 2008, 03:12 AM

Yeah, that's what it does. The side effect is that it stays clean further up the dial. The sound with the volume all the way up is the same, but saturation sets in around say 12:00 instead of 09:00.

steven

BrassRat · June 27th, 2008, 09:51 AM

Quote:

Originally Posted by sjhusting

...Unless you are a hopelessly obsessive neurotic...

I went this route. The whole thing start to finish probably took me about 24 hours on the bench. Here are a few of the things I did:

1) make spare copies of the layout diagram and the electrical schematic. Use a highlighter to mark what you've done on the layout diagram as you go. Toward the end (while you can still see the back of your board), trace the circuit as built and highlight electrical schematic. This is good for insuring that you have the right number of connections at each junction. Finish highlighting the layout diagram and schematic in lock step as you install the board and finish the final connections.

2) There are two posts in this thread that are pure gold:
Test Protocol - thanks Steven
Connection details - thanks Johnny
Print these out. Use the highlighter you bought for #1 above to check off info that you verify and tests that you do. Johnny's is the Rosetta stone if you don't already know how to read the electrical schematic.

3) Before I ever put B+ to the filter caps, I took a final pass at DC resistance between each pair of tube lugs to be sure I didn't have any accidental shorts in my socket wiring (or elsewhere). This goes faster than it sounds because once you've tested V1p1 against all others (on all tubes, not just V1), you don't never have to return to that pin, then you do V1p2 (test against all lugs except V1p1 - you've already done that), etc - so the process get progressively faster as you go. The whole test probably took 5 minutes, but gave me a lot of confidence that any bridged pins are supposed to be.

My reward: zero bugs at power up. Turned it on and it worked. Priceless.

T_red7882 · June 28th, 2008, 02:05 PM

is there a video anywhere on youtube of someone draining filter caps?

koen · June 30th, 2008, 10:22 PM

Still chasing some noise...

I resoldered all V1 connections, and it seemed a bit better. I also found that when I measure the resistance between the potmeters housing and ground, it isn't completely zero. Could this be a cause? If so, how do I make sure that they are all grounded - I could just solder a wire between all of them and then to the brass plate, but I don't want to introduce any ground loops.

sjhusting · July 1st, 2008, 02:53 AM

What does 'isn't completely zero' mean to you? Nothing is a perfect conducter and you will get a fraction of an ohm resistance when measuring through the chassis.

steven

JohnnyCrash · July 1st, 2008, 04:05 AM

Quote:

Originally Posted by koen

Still chasing some noise...

I resoldered all V1 connections, and it seemed a bit better. I also found that when I measure the resistance between the potmeters housing and ground, it isn't completely zero. Could this be a cause? If so, how do I make sure that they are all grounded - I could just solder a wire between all of them and then to the brass plate, but I don't want to introduce any ground loops.

First, what kind of noise?

Low frequency hum?
High frequency hiss?
High frequency crackles and pops?
Buzzing caused by the amp running loud, or on low/Bass notes?

Is it intermitten or all the time? Does it only become a problem when the amp is turned up? Is it in one channel but not the other?

How did you setup your 6.3v heater center tap? Artificial 100 ohm resistors or a real center tap? Have you tried putting the AC heaters on top of DC like at the 6V6's cathodes?

Are you using shielded wire? Are your connections longer than they need to be? Have you tried new tubes (I had a noisy triode on a 12AY7, while the other triode was fine)?

We'll iron out these kinks - it'll be sounding great and noiseless in no time :)

koen · July 1st, 2008, 07:50 AM

Quote:

Originally Posted by JohnnyCrash

First, what kind of noise?

Low frequency hum?
High frequency hiss?
High frequency crackles and pops?
Buzzing caused by the amp running loud, or on low/Bass notes?

Is it intermitten or all the time? Does it only become a problem when the amp is turned up? Is it in one channel but not the other?

It's mostly high frequency hiss. Als when I tap lug 2 of V1 there is some crackle and pop noises.

With all three pots at zero, there's no noise.
With both volume pots halfway and the tone at zero, there is no noise.
With both volume pots at 3 quart and the tone at zero, there is almost no noise.
The noise really becomes suddenly louder when I move the vol pots from 10 to 12 (either channel).
No matter where the vol pots are, the noise gets louder when I open the tone pot.

Quote:

Originally Posted by JohnnyCrash

How did you setup your 6.3v heater center tap? Artificial 100 ohm resistors or a real center tap? Have you tried putting the AC heaters on top of DC like at the 6V6's cathodes?

Not sure if I understand that question. The two 100 Ohm resistors are soldered on the socket from 2->8 (V4) and 7->8 (V3).

Quote:

Originally Posted by JohnnyCrash

Are you using shielded wire? Are your connections longer than they need to be? Have you tried new tubes (I had a noisy triode on a 12AY7, while the other triode was fine)?

The only piece of shielded wire provided with the Mission kit goes from one of the volume pots to lug 2 of V2, and only one side of the shield is soldered to ground. I did try another 12AY7 tube in V1 but that didn't help.

koen · July 1st, 2008, 07:59 AM

Quote:

Originally Posted by sjhusting

What does 'isn't completely zero' mean to you? Nothing is a perfect conducter and you will get a fraction of an ohm resistance when measuring through the chassis.

steven

Ok, thanks - it's not that bad then

teleamp · July 1st, 2008, 09:50 AM

Quote:

Originally Posted by koen

It's mostly high frequency hiss. Als when I tap lug 2 of V1 there is some crackle and pop noises.

Resolder that joint. It either is a bad mechanical connection or a cold solder joint.

Quote:

Originally Posted by koen

With all three pots at zero, there's no noise.
With both volume pots halfway and the tone at zero, there is no noise.
With both volume pots at 3 quart and the tone at zero, there is almost no noise.
The noise really becomes suddenly louder when I move the vol pots from 10 to 12 (either channel).
No matter where the vol pots are, the noise gets louder when I open the tone pot.

Some noise is normal, the way the tone control is wired in the 5E3 circuit, it adds gain as it is turned.

Quote:

Originally Posted by koen

The only piece of shielded wire provided with the Mission kit goes from one of the volume pots to lug 2 of V2, and only one side of the shield is soldered to ground. I did try another 12AY7 tube in V1 but that didn't help.

You don't need any shielded wire anywhere else.

Sounds like all that is wrong is minor lead dress issues and at least one bad solder joint.

Can you post some pics of the socket wiring?

koen · July 1st, 2008, 10:41 AM

Quote:

Originally Posted by teleamp

Can you post some pics of the socket wiring?

See the link under my avatar. I can add more later if these aren't clear enough.

teleamp · July 1st, 2008, 11:08 AM

Quote:

Originally Posted by koen

See the link under my avatar. I can add more later if these aren't clear enough.

Do you have any pics of the socket wiring? It could be as simple as one wire too close to another.

koen · July 1st, 2008, 11:45 AM

Quote:

Originally Posted by teleamp

Do you have any pics of the socket wiring? It could be as simple as one wire too close to another.

I will take a picture tonight and post it here. Watch this space...

koen · July 1st, 2008, 12:00 PM

Quote:

Originally Posted by teleamp

Some noise is normal, the way the tone control is wired in the 5E3 circuit, it adds gain as it is turned.

Any idea why the noise level suddenly increases much faster between 10 and 12 on the volume pots?

BTW, all these observations were without a guitar plugged in.

teleamp · July 1st, 2008, 12:19 PM

Quote:

Originally Posted by koen

Any idea why the noise level suddenly increases much faster between 10 and 12 on the volume pots?

BTW, all these observations were without a guitar plugged in.

Some noise is normal as you add more gain.

With the amp at volume and making the noise (nothing plugged in), ground pins 2 & 7 of V1, if that quietens the amp, you have issuses with the input jacks or wiring.

koen · July 1st, 2008, 07:57 PM

Here are pics for V1 and V2 - hope everything is visible.

T_red7882 · July 6th, 2008, 08:32 PM

well, i finally got started on my mission kit today. my buddy and i took turns doing the little stuff (he already builds great cabs, and we're doing this kit together to learn... its my amp though), and we're ready to start soldering. Its ridiculously hot, so we're going to hold off till tomorrow for the meat of things. Here are a few pics:

here you can see we got the switches and such put in:

we, know we have ot rotate some stuff a little, but it moved along swimmingly. Can't wait to get into the meat of things tomorrow.

JohnnyCrash · July 6th, 2008, 11:16 PM

Very cool.

Perhaps we should start new threads? Since the original poster, two new builders are making this one hard to follow...

Besides, having multiple threads with more amp photos is fun :)

I can't wait to see how your first build goes!

koen · July 7th, 2008, 08:59 AM

Are you doing the dishes a the same time?

1293 · July 7th, 2008, 10:21 AM

Your cathode caps are backwards.

T_red7882 · July 7th, 2008, 02:24 PM

Haha, my current pad has no garage (ahh the joys of renting) so the kitchen table is my build area. And yeah, we know they're backwards, thays why i said we had to rotate some stuff. I'll be posting the rest of this build at this thread:

http://www.tdpri.com/forum/amp-centr...-2x12-cab.html

koen · July 22nd, 2008, 10:08 PM

*bump*

As reported earlier, there was -imho- quite some hiss in my 5E3 build. So today, I took it to a local repair shop. The guy turned it on, and said, "Oh, that's normal".

He also complimented me on a nice job I did soldering it. He only found one place that may need a resolder.

So, I'm done!

Thanks everyone on this forum for their help, tips, suggestions, etc!!!

Cat · September 11th, 2008, 11:42 AM

Just read this whole thread and it has been fantastic. There's some real knowledgeable guys on here (already knew that) who have put a lot of time and effort into providing invaluable information on the build process.

Its really going too help with my first build that Im about to embark on.

Cat

June 27th, 2008, 03:12 AM	#202 (permalink)
sjhusting Tele-Holic Join Date: Jul 2003 Location: Germany Posts: 684 15 Photos	Yeah, that's what it does. The side effect is that it stays clean further up the dial. The sound with the volume all the way up is the same, but saturation sets in around say 12:00 instead of 09:00. steven __________________ "When you have to kill a man it costs nothing to be polite" - WSC

July 1st, 2008, 02:53 AM	#206 (permalink)
sjhusting Tele-Holic Join Date: Jul 2003 Location: Germany Posts: 684 15 Photos	What does 'isn't completely zero' mean to you? Nothing is a perfect conducter and you will get a fraction of an ohm resistance when measuring through the chassis. steven __________________ "When you have to kill a man it costs nothing to be polite" - WSC

September 11th, 2008, 11:42 AM	#223 (permalink)
Cat Tele-Meister Join Date: Sep 2004 Posts: 378	Just read this whole thread and it has been fantastic. There's some real knowledgeable guys on here (already knew that) who have put a lot of time and effort into providing invaluable information on the build process. Its really going too help with my first build that Im about to embark on. Cat __________________ No Telecasters = No Led Zeppelin, No Springsteen, No Jeff Buckley, No Eric Clapton, No Nothing. Long live the TELECASTER

June 27th, 2008, 01:42 AM	#201 (permalink)
JohnnyCrash Poster Extraordinaire Join Date: Mar 2005 Location: Lost Angeles and Orange County Posts: 7,128	I believe another Volume mod is to make the Volumes independent, instead of interactive.

June 28th, 2008, 02:05 PM	#204 (permalink)
T_red7882 Tele-Holic Join Date: Dec 2006 Location: San Francisco Age: 26 Posts: 828	is there a video anywhere on youtube of someone draining filter caps?

June 30th, 2008, 10:22 PM	#205 (permalink)
koen Tele-Meister Join Date: May 2007 Location: East of the Mississippi Age: 44 Posts: 208 8 Photos	Still chasing some noise... I resoldered all V1 connections, and it seemed a bit better. I also found that when I measure the resistance between the potmeters housing and ground, it isn't completely zero. Could this be a cause? If so, how do I make sure that they are all grounded - I could just solder a wire between all of them and then to the brass plate, but I don't want to introduce any ground loops.

July 1st, 2008, 07:57 PM	#216 (permalink)
koen Tele-Meister Join Date: May 2007 Location: East of the Mississippi Age: 44 Posts: 208 8 Photos	Here are pics for V1 and V2 - hope everything is visible.

July 6th, 2008, 08:32 PM	#217 (permalink)
T_red7882 Tele-Holic Join Date: Dec 2006 Location: San Francisco Age: 26 Posts: 828	well, i finally got started on my mission kit today. my buddy and i took turns doing the little stuff (he already builds great cabs, and we're doing this kit together to learn... its my amp though), and we're ready to start soldering. Its ridiculously hot, so we're going to hold off till tomorrow for the meat of things. Here are a few pics: here you can see we got the switches and such put in: we, know we have ot rotate some stuff a little, but it moved along swimmingly. Can't wait to get into the meat of things tomorrow.

July 6th, 2008, 11:16 PM	#218 (permalink)
JohnnyCrash Poster Extraordinaire Join Date: Mar 2005 Location: Lost Angeles and Orange County Posts: 7,128	Very cool. Perhaps we should start new threads? Since the original poster, two new builders are making this one hard to follow... Besides, having multiple threads with more amp photos is fun :) I can't wait to see how your first build goes!

July 7th, 2008, 08:59 AM	#219 (permalink)
koen Tele-Meister Join Date: May 2007 Location: East of the Mississippi Age: 44 Posts: 208 8 Photos	Are you doing the dishes a the same time?

July 7th, 2008, 10:21 AM	#220 (permalink)
1293 Tele-Afflicted Join Date: May 2006 Posts: 1,574	Your cathode caps are backwards.

July 7th, 2008, 02:24 PM	#221 (permalink)
T_red7882 Tele-Holic Join Date: Dec 2006 Location: San Francisco Age: 26 Posts: 828	Haha, my current pad has no garage (ahh the joys of renting) so the kitchen table is my build area. And yeah, we know they're backwards, thays why i said we had to rotate some stuff. I'll be posting the rest of this build at this thread: http://www.tdpri.com/forum/amp-centr...-2x12-cab.html

July 22nd, 2008, 10:08 PM	#222 (permalink)
koen Tele-Meister Join Date: May 2007 Location: East of the Mississippi Age: 44 Posts: 208 8 Photos	bump As reported earlier, there was -imho- quite some hiss in my 5E3 build. So today, I took it to a local repair shop. The guy turned it on, and said, "Oh, that's normal". He also complimented me on a nice job I did soldering it. He only found one place that may need a resolder. So, I'm done! Thanks everyone on this forum for their help, tips, suggestions, etc!!!