My first Rocket... Need help!

[angelodp]

Heaters on the power tubes look like they may be injecting some noise into the tubes. Look at the way those heaters are typically done, away from other wires and away from the tubes. You may also be generating some oscillation with the large preamp caps up in the air like you have. I know you have heard this, but the nature of Trainwreck amps is such that topology and arrangement of wires and components is quite critical. Using Ron's build as an example one can see the minimal nature of the wiring, the chassis looks almost empty.

Ange

[showsii]

Everyone,

Thank you so much for all the feedback and help thus far on my current build. I have come to the decision that I essentially want to start over. I know now after a good conversion with Ange earlier today some things that will be helpful in the future. So instead of trying to get this thing to work, I want to zealously follow Ron's pictures of his rocket. So to hopefully start with a better foundation to work with instead of you guys trying to figure out my mess of an amp! ha.

So I will begin Tomorrow, I will spend some time with the NASA soldering file and that video that was posted.

Please feel free to suggest any tips as I begin re wiring my board (most likely with new components) and lead dressing. Anything you learned with lead dress that might be helpful, ect...

Ok, Ill be back soon with hopefully some good news!


Thanks again everyone


Ian

[angelodp]

Ever see the Great film " French Connection " with Gene Hackman, a classic and has one of the all time great chase scenes in it. Story goes they started production and after day two they looked at their dailies and stopped to confer. They decide it was not what they were after in terms of the grittiness and feel of the movie. They started all over again. You can Imagine the cost of starting a major motion picture after a few days. They went on to make a great movie IMHO.

Now be careful taking things apart and check out what you have if you are in fact starting over.

You do have a solder sucker right?

[Ian444]

Showsii, you still haven't eliminated the power tubes, power amp wiring and OPT wiring as the possible cause of the problem. Some output tube voltages would be nice before you tear it down, in case there is a big problem there. If those output tube voltages all look solid, then sure, I would then rebuild the amp. No need to use all new components unless you have to.

[amplifiednation]

What is the green wire attached to the b5 turret on the board? It has heatshrink on it. Is that the underboard jumper?

[overtone]

Showsii, you still haven't eliminated the power tubes, power amp wiring and OPT wiring as the possible cause of the problem. Some output tube voltages would be nice before you tear it down, in case there is a big problem there. If those output tube voltages all look solid, then sure, I would then rebuild the amp. No need to use all new components unless you have to.

+1 on the above quote because I guess you will be re-using the major components. Overall I think that you will be happier rebuilding the amp sonner rather than later. I think it is really great that you want to move forward and develop your skills. But if it is not too late, these are a few things I would still do before a tear down:
1. log all the voltages on each of your EL84s to see hopefully that they all come in the same ball park. If not, let us know because, one tube may be "current hogging".
2. If you can, try running it with a different GZ34 rectifier tube. There is something about that 5V cable that looks to me as though it burnt it's insulation where the twists rest against each other. It may have been caused be something else. For a test you could also rig up a diode rectifier instead, but the voltages will go much higher. (A dropping resistor could be chosen to get the B+ back in line.)
3. Change out you black silver mica caps. At this test-stage you can use any cap of similar value with an adequate voltage rating.

You asked for any other general tips:
- bending the component leads: with a pair of pliers hold the lead close to the component body and bend the lead from the outer edge of the pliers. Try never to bend the lead directly at the body. This helps prevent any stress on where the leads exit the component.
- soldering small components: place a crocodile clip onto the lead, next to the body, before soldering which acts as a small heat sink. With practice you will get to be so fast that you will not need to do that. If you think that you may have fried a component, stay on the safe side and use a new one. It will save time in the long run.

By the way. I cannot really follow how taking the bleed resistors out would bring the B+5 into line.

[RJ Guitars]

Ian,

Just made a trip overseas and missed the early posts on this thread. You've got some good guys to work with here and you'll get this nailed down. I sent you some info last night on parts.

For your photos if you have the chance to take the amp outside during the day and then photograph in a shaded spot (no direct sunlight) you'll get some natural light on everything that will help the photo quality. For some of us the eyes are getting kinda old and it's hard to see the details without more light.

It will all be worth it when you get it done.

rj

[angelodp]

Welcome back rj, are you back on Champ duty...

Ange

[RJ Guitars]

Welcome back rj, are you back on Champ duty...

Ange

Ange,

Sorry, that note was misleading or maybe I am confused. At any rate I am still away for another week. I have been busy with design work and look forward to amp building very soon...

rj

[angelodp]

Sorry, I though you were back home and getting back to the Supre Champ.

Be well

Ange

[showsii]

Showsii, you still haven't eliminated the power tubes, power amp wiring and OPT wiring as the possible cause of the problem. Some output tube voltages would be nice before you tear it down, in case there is a big problem there. If those output tube voltages all look solid, then sure, I would then rebuild the amp. No need to use all new components unless you have to.

+1 on the above quote because I guess you will be re-using the major components. Overall I think that you will be happier rebuilding the amp sonner rather than later. I think it is really great that you want to move forward and develop your skills. But if it is not too late, these are a few things I would still do before a tear down:
1. log all the voltages on each of your EL84s to see hopefully that they all come in the same ball park. If not, let us know because, one tube may be "current hogging".
2. If you can, try running it with a different GZ34 rectifier tube. There is something about that 5V cable that looks to me as though it burnt it's insulation where the twists rest against each other. It may have been caused be something else. For a test you could also rig up a diode rectifier instead, but the voltages will go much higher. (A dropping resistor could be chosen to get the B+ back in line.)
3. Change out you black silver mica caps. At this test-stage you can use any cap of similar value with an adequate voltage rating.

You asked for any other general tips:
- bending the component leads: with a pair of pliers hold the lead close to the component body and bend the lead from the outer edge of the pliers. Try never to bend the lead directly at the body. This helps prevent any stress on where the leads exit the component.
- soldering small components: place a crocodile clip onto the lead, next to the body, before soldering which acts as a small heat sink. With practice you will get to be so fast that you will not need to do that. If you think that you may have fried a component, stay on the safe side and use a new one. It will save time in the long run.

By the way. I cannot really follow how taking the bleed resistors out would bring the B+5 into line.

Tony,

I already had the amp ripped apart before I had a chance to log the power tube voltages. I will try to get my hands on another rectifier tube if this "redo" doesn't pan out. About the burn marks, I went back and checked and it looks like a yellow film. It peels right off with not effect to the wire. So I guess no harm done? If this redo does not pan out I will definitely grab some different mica caps.

Good word about the bending and heat sink! (Ange has been walking me through the heat sink thing as well) I will definitely implement those methods.

About the bleed resistors and B+5 voltage. I have no idea if that would have made a difference. If I claimed that was the fix, I go back on what I said because I have no idea. I would assume it was some re-flowing of some solder joints, or something of that nature. Once again, no idea.

Thanks for the continued and future help. It is greatly appreciated.

Ian

[showsii]

Ian,

Just made a trip overseas and missed the early posts on this thread. You've got some good guys to work with here and you'll get this nailed down. I sent you some info last night on parts.

For your photos if you have the chance to take the amp outside during the day and then photograph in a shaded spot (no direct sunlight) you'll get some natural light on everything that will help the photo quality. For some of us the eyes are getting kinda old and it's hard to see the details without more light.

It will all be worth it when you get it done.

rj

Rj

Thanks for the links and the helpful advice. That is a great idea that I did not think of about taking the photos outside. I have a few photographer friends that I might get to take some pics once I finish the "re-build". So y'all can have some good photos to catch my mistakes.

Thanks again Rj

Is there a post dedicated to "rebuilds"..? If this thing works and is acceptable maybe there should be a "before and after" "amp make over" post.

Ian

[RJ Guitars]

Ian,

you'll get there, maybe sooner than later with your added experience. Once you get a Rocket right it will sound pretty awesome and you'll get a lot of enjoyment out of it.

Soldering is an art form that requires running the balance between running hot enough to heat all the parts up to the melting point of the solder without melting the insulation off of the wire. If you look at the Allyn Meyers Rocket build photos that is a great demo of some text book perfect soldering.

Thanks for posting your build efforts up. We all appreciate the chance to learn a little something as you sort this out.

rj

[overtone]

well said RJ.

Ian - no harm done on the 5V wires, it is probably just some stray transformer varnish!
Looking forward to the next incarnation of your Rocket.

Best,
tony

[showsii]

Hello everyone

First of all, thanks for the encouraging words and all the help. I appreciate it very much. I have heard how helpful everyone is on TAG, and you all are definitely living up to your reputation.

Here are a few low res pictures of where I am right now. (I will get some high res photos very soon, and for the final product. Just want to put some up just in case I really messed something up)

The pictures of the preamp board are NOT soldered yet. These are all just my mechanical connections. Also a few components are missing, they are on the way, will be in Wednesday.

The black stuff on the OT blue and white wires is liquid electrical tape. I was going to use it to hold down the wires. I know, I know.. Never again. I promise. :/

Also, My ground wires for the filter caps are laying next to the filter caps.. they are not connected yet.