1st build, need a little help

[DFMoore]

I think I'll take a few days off of troubling shooting and start back fresh going through the schematic step by step as Tubeswell suggested.

Thanks,

[nathanneedles]

I can't tell for sure from your pictures, but it looks like the 68K coming off of pin 7 connected to the red cable might be grounded to the chassis. If so, that should be elevated and connected to the pin and cable only.

[DFMoore]

That post should be shielded, but I will double check with my meter to make sure.

Thanks

[DFMoore]

Ok, back at it. The post that connects the 68k resister to pin 2 is sheilded, no grounding out there. I am confident the input is wired correctly. I have checked each of the wires ans they appear to be correct. Could i have the wires from my output transformer mixed? The wire colors are green/ black, these connect to my output, and brown/blue, to the diodes and pin 3 of the 6n6c respectively. Thoughts?

[surfsup]

DFMoore, hmm 24 hrs and back at it! Can't help ourselves can we?

On Monday you wrote:

Just rewired the input as suggested. I went from very low distorted volume to none.

If this statement was true, you would have changed the input wiring from producing sound to producing nothing, and therefore there is a problem with the input wiring...yes? Do you have any better photos or new voltage readings after the amp went totally silent?

[RJ Guitars]

does the output wiring look the drawing below? Your voltages kinda indicate that the PT is wired correct.

Also, maybe use a regular piece of wire on the input and from the pot to pin 2 rather than the coax while you trouble shoot. The coax can short out if you get it hot and that is very hard to find.

keep going... you will succeed!

rj

[DFMoore]

I failed to state that I had gone back and rewired the input jack similar to how I had originally had it. I currently get low, low volume with heavy distortion. Attached are three, hopefully, more detailed pictures. Please do not make fun of my soldering....it is my first attempt at this. And yes I couldn't let this set for a few days...I have become addicted to this project.

[RJ Guitars]

I failed to state that I had gone back and rewired the input jack similar to how I had originally had it. I currently get low, low volume with heavy distortion. Attached are three, hopefully, more detailed pictures. Please do not make fun of my soldering....it is my first attempt at this. And yes I couldn't let this set for a few days...I have become addicted to this project.

I appreciate your boldness in sharing your work here... it's a good crew and only a real low life dog would say anything but encouraging words... somewhere there is a file of their first project and you never know who might have a copy to post should things get out of hand??

Anyway, I keep thinking about this low distorted sound that you are able to get - it is telling us something. I am curious if you take the wire off of the resistor going into pin 7, and touch pin 7 with an insulated metal probe (like the test lead of you meter). Do you get hum or pop? If yes, then can you tell if it gets louder or quieter when you turn the volume control up and down? If no, then proceed to the next stage...

Remove the wire going into pin 2 , and repeat the probe test. Any hum or pop coming out the speaker when you touch pin 2 with an insulated metal probe?

If you have a chance to run those two tests and report back we can figure out which way to go next.

rj

[Tillydog]

Pardon me butting in, but I think there's a ground connection missing from the cathode resistor on the first valve (tube).

Andy

[Firestorm]

Pardon me butting in, but I think there's a ground connection missing from the cathode resistor on the first valve (tube).

Andy

Yes, check that. Also look at the wiring of your volume pot; it looks backwards.

[RJ Guitars]

Pardon me butting in, but I think there's a ground connection missing from the cathode resistor on the first valve (tube).

Andy

Yes, check that. Also look at the wiring of your volume pot; it looks backwards.

I think that is not a butt in but a rather good catch and I am betting that makes a significant difference to complete that path...

[Tillydog]

...I am betting that makes a significant difference to complete that path...

Fingers crossed!

Andy

[DFMoore]

Is this the reisister from pin 8 of the preamp tube? If so it is grounded, you cannot see the wire in the picture.

I'll double check the volume pot and probe the different pins to see if there is any popping and I'll report back.

[Tillydog]

Is this the reisister from pin 8 of the preamp tube? If so it is grounded, you cannot see the wire in the picture.

Just to be clear, I mean the resistor from pin 3 of the preamp tube - It's shown as pin 8 on the schematic & layout, but (if I'm counting pins in the right direction ) its on pin 3 the way you've wired it.

[RJ Guitars]

David,

I wanted to verify that 1st stage cathode ground. You said it was grounded but we can't see the wire. Maybe it is under the board but I wanted to verify just to make sure. In my attached drawing, do you get zero ohms between points 1 and 2?

rj