It Works

Well sort of.

I made the suggested changes the amp tech told me to do, but it didn't help. So I hit a couple of the solder joints again, but the biggest change I did was to connect the white (8ohm) output tranformer wire directly to the speaker output - I basically disconnected the switch.

I am getting a guitar sound out, but it is very soft (low volume). It needs to be louder and infact for a brief second it sounded like it became louder almost like something that wasn't fully connected made sudden contact.

I know it's working and now I just need to do some more trouble shooting.

Fixed and about to fire her up

Here what I've fixed:

The very first thing the amp tech noticed was my ground connection at the power transformer - The weren't connected so I actually had no ground.

Then as we were looking he noticed one electro cap that was in backwards - it was a small one; not one of the large ones that can explode. As we were talking I noticed another small one that was backwards.

He also found a couple of weak solder joints and two of them he was able to disconnect with a tug. He recommended that I put a little more heat and solder on a couple of places.

Overall, he said for a first time build it looked pretty good at least as far as soldering and running the wire. He wants to hear it after its finished. Since it is near tax time, I probably won't buy the cabinet until after April 16. - I hope in mid May to order it.

Here are the pics.

In each of these first two pics there is a black capacitor. On these caps at one end there is a small + sign. Those + signs need to be towards the bottom of the board. If you look at some earlier pics I posted you can see two big one on the far left of the board and those + are a LOT easier to see.

In this pic you can see the ground connection inbetween all of the wires. It is fastened to one corner of the power transformer. I made the ground connections to each of the lugs so they are all ground together, but I didn't make a connection from those lugs to the actual ground. There is a small wire in there, but it's hard to see unless you know what you're looking for.

I'm ready to fire her up. I'll take one (or 2) last looks and put the tube in and power her up!

Found some Problems

I just got back from my local amp tech/repair shop - he offered to take a quick look and see anything obvious that may be wrong.

He found some things right off the bat and I'll begin working on them later this evening. Most of the fixes are easy, but there are two things that I may or may not have to remove the board containing all the caps and resisters. I have two caps that were in place with the wrong polarity. Fortunately, they are small caps and not the big ones.

I take some pics and post of my mistakes and the fix.

Fired it up and...

Ok I fired up the amp last week and nothing! I've been trying to trouble shoot it for the past week. Here are a few of my mistakes that I have fixed but there is still no sound. I say no sound, there is a slight hum in the speaker, just no sound from the guitar.

I had the wrong input jack. I don't know how I missed this - The output jack I used only had two prongs and the correct jack is a switched jack with three prongs.

I found a wire that may have been shorting the circuit. It was the wire going from the volume pot to the tone pot. When the pots were screwed into the chassis the connections touched the brass grounding plate. I moved the wire around to the bottom side of the pots.

That's the latest update. I'll be out of town all next week and I think when I get back I'll have to take it to my local amp tech and see if he can help me.

I did buy the speaker today. I bought a 12" Eminence Wizard speaker from http://www.nationalspeaker.com/ as they are 6 miles from my house. After taxes the cost was $85

Few more pics

Here are a few more pictures

It is Finished!

I finished the last bit of soldering tonight!

Here are some pics

The next steps are to double and triple check all of my connections for both the correct wiring and to check the solder joints. A cold solder joint has a dull appearance. All of the solder connections should be shiny.

As for plugging in and fireing up. Well there are some safety concerns. First amps, even small ones like this produces lethal voltages. Some safety precautions are in order.

I need to make a circuit in the power cord to check for problems. Here is a quote from the Aikens Amp web site, "make a fixture with a light bulb in a socket that is in series with one side of the AC line - if the amp has a major short, the light bulb will light up instead of blowing the fuse or vaporizing your new power transformer."

In fact, go to the web site and read their whole safety page found here: http://www.aikenamps.com/SafetyTips.html

It has some great advice that could save your life.

I have to go out of town this week, so I won't get to fire this puppy up for at least a week - I need to buy the stuff to make the safety curcuit. It shouldn't be long now!!

Tools for the build

I thought I'd take a minute and list some basic tools needed for this job for those who are considering this build or any amp build. Keep in mind this is my first build so I'm not an expert.

• Wire cutter & stripper.
• Small screw driver - phillips and standard depending on what type of mounting hardware you buy.
• A small set of needle nose pliers - I have a set of small tools I bought at sears a long time ago and I think they still sell them. See the picture below. The long needle nose ones have been extremely helpful in bending cap/resistor wires.
• Drill - The main thing for this amp was that I had to drill a hole for the ohm switch. For the twisting of the wires it is helpful, but you can build a small amp like this without it. If you build an amp with a bigger chassis and longer wire runs then it would definately help.
• Soldering iron - a variable temp iron. Why variable temp? For the light electronic parts you don't want to burn them up with a high watt iron, but when making ground connections to the chassis you need a hotter iron. If you have two irons already then this doesn't matter. I picked up this soldering iron for around $50 + shipping here: http://www.howardelectronics.com/xytronic/379.html and this place has it for $40 + shipping http://www.assemblyoutfitters.com/shop/item.aspx?itemid=2163 It also helps to have a tip with a fine point because some of the connections are small.
  

Off the top of my head that's a basic list. Here are some pics