THE PERCOLATOR 2 Watt Tube Amplifier Kit Assembly Instructions INTRODUCTION ...................... 3 CAUTIONS, WARNINGS, DANGERS ................. 3 BUILDING THE AMPLIFIER ..................5 WHAT YOU WILL NEED ..................5 WHAT’S IN THE BOX ..................... 6 POPULATING THE PRINTED CIRCUIT BOARD ............10 LOADING THE CHASSIS ..................
“Compactron.” Compactron tubes have multiple amplifier sections in one bottle. The tube in the Percolator has two triodes and one sharp cut-off pentode. That’s the same topology as the Fender Champ, but in one bottle! This tube was never intended to be used in an audio circuit (it was originally designed for use in various parts of a TV circuit), but it works and sounds great in a guitar amplifier.
If you do not know what you are doing, and you handle the capacitors recklessly, YOU COULD KILL YOURSELF OR THE GUY NEXT TO YOU! Zeppelin Design Labs LLC takes no responsibility for any harm that may come to anyone or anything through this product.
• Wire stripper, to strip 18-gauge stranded and 20-gauge solid core wire • Flush cutters or small diagonal cutters • Needle-nose pliers • X-Acto knife, or razor blade • Solder sucker or solder braid – optional, but very handy if you have to remove / repair any components! 2.
Table 1: Percolator Bill Of Materials Loose in the box: Part # Description Notes CA05.1 Cabinet Top/Bottom Longer CA05.2 Cabinet Side Shorter CB03 Power Cable IEC 6’ CH03.1 Chassis Top CH03.2 Chassis Base Plate GC02 Grill Cloth Black/Silver/Beige GF02.1 Grill Frame Top/Bottom Longer GF02.2 Grill Frame Side...
SC63 Philips Sheet Metal Screw - Pan head 8x1/2” Assembling the chassis SC66 Philips Sheet Metal Screw - Pan head 6x5/8” Attaching the feet SC67 Philips Sheet Metal Screw - Flat head 6x1” Installing the chassis in the cabinet SC68 Philips Sheet Metal Screw - Pan head 10x3/8 Attaching the fins SP11...
“component side” of the board, which is the side that has the Zeppelin Design Labs logo on it. The other side of the board is called the “solder side”, which, as the name implies, is the side on which the legs of the components are soldered to the board.
Resistors R13 & R17 are exceptions to the normal hole spacing, so for those two components you’ll have to estimate where to bend the leads. Figure 2: Component Values and Locations a. Start with the 22K resistors (R1, R6, R11), labeled RED, RED, ORANGE, GOLD. Compare to its picture in the BOM.
b. Continue with the 220K resistors (R5, R9, R10), labeled RED, RED, YELLOW, GOLD. c. Continue with the 1.5K (or 1K5) resistors (R7, R14, R17), labeled BROWN, GREEN, RED, GOLD. R17 has a larger lead spacing than most of the other resistors so estimate where to bend the leads.
Capacitors: The Percolator uses 3 different types of capacitors: Film capacitors, tiny ceramic disc capacitors, and electrolytic capacitors. Film and ceramic caps can be installed in either direction on the circuit board (the legs can be reversed in their holes). But electrolytic caps are polarized, meaning they will only work when they are installed in the correct orientation.
has “+” signs where the positive (longer) lead goes. The negative side of the caps have white stripes pointing to the negative lead. d. Install all of the smaller electrolytic caps (C2 ,C5 ,C8 ,C12). Solder and clip the leads. e.
Jumper wire: Use one of the leads that you just clipped off of the big electrolytic capacitors (C9, C10, or C11) as this jumper. Use your needle nose pliers to bend the lead in the shape of a staple. Install the jumper in the holes and solder the leads. Bridge rectifiers (Part # BR1, BR2): Bridge rectifiers have 4 leads and it is very important to make sure each lead goes in the correct hole.
Input jack (Part # J1): Remove the plastic nut from the input jack and put it aside until the next section. Snap the input jack into its holes on the circuit board. Make sure you solder the leads well. The leads are too short to cut on this component so don’t bother. Potentiometer (Part # VR1): Remove the nut and washer from the shaft of the pot and put them aside until the next section.
the board because this component is switching high voltage. The front two pins just act as anchors for the switch and are connected to the large piece of metal on the front of the component. Extra heat may be needed to secure these pins properly because the large piece of metal tends to act as a heat sink.
11. Feedback loop wire (Part # CB10.1): Strip about 1/4” (6mm) of insulation from each end of the 10.5cm single stranded hookup wire. Solder one end of this wire to the FBL hole so the wire is emerging from the component side of the board. The other end of the wire will be used in the 35, 36 next section.
13. 10.5cm Twisted pair hookup wire (Part # CB10.2): This wire is used to transmit the 6.3V heating filament voltage to the tube. Untwist about 1/4” (6-7mm) of each end of the twisted pair and straighten the ends out with your pliers. Strip off about 1/8”...
14. Tube socket (Part # SK10): a. Before installing the tube socket, we need to help prepare it to easily seat the tube. These sockets come a little tight from the factory, so it is helpful to loosen up the place where the tube pins fit in.
The circuit board is now complete! Double check all your solder joints and make sure everything is well soldered and making good connections. If anything looks at all sketchy, touch-up each solder joint. It’s much easier to fix a problem with the board now than once it is installed in the chassis.
LOADING THE CHASSIS Note the chassis face with the big square hole is the BACK of the amp! Generally, hold the chassis with the back AWAY from you unless told otherwise! This will help avoid building the thing backwards. Grommets: Pop the 4 rubber grommets (Part # GR02) into the holes on top of the chassis as shown.
b. The power transformer goes on the RIGHT side of the chassis (with the back of the chassis AWAY from you). Pass the red and brown wires through the rear-right grommet, and the black wires through the front-right grommet. Align the transformer mounting holes with the holes in the chassis.
c. Now you need to twist the wires. Twist the black wires together somewhat tightly, but do not over twist the wires near where they emerge from the transformer. You do not want to stress the wires near the transformer coil, because they can easily break on the inside of the transformer, and that would be very bad.
machine screws (Part # SC38) and two M3 keps lock nuts (Part # NU10). c. Twist the green and black wires together, and twist the red and blue wires together, in the same way as the power transformer wires. Once again, be mindful not to over twist the wires close to the coil.
Label (Part # PL11): Clean the front of the chassis with a clean rag moistened with isopropyl alcohol, denatured alcohol, or rubbing alcohol. Clean it thoroughly, and allow any liquid to dry completely. Be careful NOT TO TOUCH the face AT ALL after cleaning.
b. Carefully place the circuit board in the chassis with the standoffs down (the standoffs resting on the top of the chassis) and the component side of the board up. The input jack side of the board should be closest to you. Slide the PCB forward as the input jack, pot, and switch fit through the holes on the front of the chassis and the tube socket is seated in its chassis hole.
d. Place the washer and nut back on the pot, and snug down with your pliers. Place the plastic nut back on the input jack, and snug it down with your pliers. Do not over-tighten this nut or the label could start warping. e.
Wiring the PCB: Once the PCB is affixed to the chassis you can attach the transformer wires. All of the wires will pass around the side of the PCB, and you will solder them on the component side of the board. a.
the wire. Thread the hook through the small hole on the grounding lug (Part # CB20) and crimp it tight with your pliers. Solder that connection. Put this assembly aside until next step. 11. IEC Power Receptacle (Part # J3): a.
c. Now solder the wires to the lug. Be careful not to use too much heat or the lug could start melting out of the plastic. d. Bend both wires slightly forward and push the power receptacle through the chassis. BE SURE TO INSTALL IT WITH THE CORRECT SIDE UP (look at the picture).
e. Place the wire coming from the right side of the power recepticle (the wire without the ground lug on it) in one of the 3 square ground pads on the PCB next to the power recepticle. Solder this wire in place on the component side of the board. f.
13. Wiring the IEC power receptacle: WARNING: If you make a mistake here, you could expose yourself or others to electric shock. Double check all your connections. a. Retrieve the lengths of wire that you cut off the power transformer earlier. Cut each of the two black wires to 4-1/4”...
14. Output jack (Part # J2): a. Remove the nut and washer from the output jack and install it on the back of the chassis. Orient the jack so the lugs are facing up, as in the picture. The washer goes on the outside of the jack, between the nut and the chassis.
15. Tube (Part # V1): a. Take the tube out of its box and closely look at the pins. Sometimes a few of the pins get bent in the handling TIP: You can tell if or shipping process from the factory. If any of the the vacuum is bad in your tube because the “getter flash”...
ONLY USE AN 8 OHM CABINET WITH THIS AMPLIFIER. WHENEVER YOU APPLY POWER TO THIS AMP, MAKE SURE IT IS FIRST PLUGGED IN TO AN 8 OHM LOAD. Make sure the Percolator’s power switch is in the off position (when the amp is upside down, the switch should be up).
Before you turn the power switch on, set your multimeter to test AC voltage. Measure the AC voltage across the IEC power receptacle as shown. Depending on several (mostly uncontrollable) factors, you should measure between 115VAC and 120VAC. The amplifier was designed to use 118VAC from the wall outlet, so the voltages listed in the test procedure are based on that.
Turn on the power switch. WARNING! As soon as you turn on the Percolator, there is HIGH VOLTAGE across several parts of the exposed circuit board. Touching the board could shock, injure or kill you! NEVER TOUCH ANY PART OF THE CIRCUIT BOARD WHEN THE AMP IS PLUGGED INTO...
WARNING: Capacitors contain high-voltage electricity hours after the amp is unplugged! Handling the capacitor could shock or burn you! If you must remove or re-solder a capacitor, either let it sit unplugged overnight, or safely discharge it as described in the tip below. Figure 3 has 11 DC test voltages (in red) with arrows pointing to the place on the circuit board where these TIP: To safely discharge...
TIP: If it turns out that you need to re-solder any of the resistors, don’t bother removing the board from the chassis to get to the solder side, just solder them on the component side of the board. Once the voltages are all within spec, carefully plug your guitar (or harp mic) into the input jack, taking care not to touch the exposed circuit board.
ASSEMBLING THE CHASSIS Turn the power switch off. Unplug any cables that are plugged in to the amp (power, speaker, instrument). Carefully seat the chassis base plate (Part # CH03.2) onto the inverted chassis. is a snug fit. Use four sheet metal screws, pan head Philips #8x1/2 (Part # SC63), two in front , two in back , to secure the chassis to the base plate.
BUILDING THE CABINET While the amp is an intermediate to advanced electronics project, the cabinet is a beginner’s woodworking project. On the other hand, while the amp can be built in an hour, it takes several hours over several days to complete the cabinet! Take your time, be careful, and you should produce a lovely solid wood cabinet to be proud of.
(like a Sharpie) • Mineral spirits, for cleanup • Clean rags • A Percolator cabinet kit (no kiddin’) A WORD ON COUNTERSINKS The overall success of this project depends somewhat on your ability to accurately countersink the wood screws, so that the heads lie just below the surface of the wood, but no deeper. There are several ways to do this: •...
of plunge until the full diameter of the bit just barely cuts into the wood. The screw should then pull the head down into the wood and just below the surrounding surface. Practice setting the depth on a scrap of pine until you like the results. ALWAYS provide a 1/16”...
With the awl, or nail and a small hammer, carefully poke a hole into the wood at the center of each cross hairs. Remove the template from the right side, flip it over and tape it face- 127, 128 down to the LEFT side and mark that piece as well. Take care when you do this that you create a PAIR of parts, not two IDENTICAL parts.
Stand up all four pieces of wood on their FRONT edges on your clean, smooth, flat work surface. Dry-fit them together. Use the bar clamp to snug the pieces together as shown. If your clamp has no plastic pads, DO NOT OVERTIGHTEN or you’ll mar the wood. It just needs to be snug. Pick one corner and line up the pieces of wood as carefully and accurately as you can.
Continue to the other three corners, loosening the clamp and lining up the corners one by one. Drill a total of 8 holes. 8. Disassemble the four pieces and lay them flat on your worktable with the outsides facing up. Still with the 1/6”...
INNER holes, further away from the corners. They are for mounting the chassis and need to be as accurate as possible. A drill press is great for this if you have one. Otherwise, be careful to hold the drill perpendicular to the wood surface. Drill and countersink a total of 15 holes. 138, 139 When you countersink, practice on the four bottom holes, where the depth is less critical.
11. Inspect the inside faces of the wood pieces for splinters or “blowout”: bits of wood standing above the surrounding surface. Clean these off with a bit of 120-grit sandpaper. 12. Re-assemble and dry fit the parts, with the front edges facing DOWN. Apply some wood glue to one end of the TOP.
14. Now attach the BOTTOM to the same SIDE, driving the screws barely snug. 15. Now apply glue to the remaining exposed ends of both the TOP and BOTTOM. Fit four screws into the remaining SIDE and maneuver them into all four little pilot holes. Align one joint tighten the bar clamp (not shown;...
16. Check the box for overall squareness: press the face flat to the table; measure diagonally across the cabinet to see if it measures the same in both directions. If necessary, install the bar 155, 156 clamp across the longer diagonal and gently tighten it to bring the box closer to square. tighten all eight screws.
Let the cabinet sit for at least 4 hours for the glue to cure. 17. If any joints are poorly mated, grind them flush with 60 or 80 grit sandpaper. 160, 161 18. Edge Detail: If you want to apply a router detail, now’s the time. There’s only room for a small chamfer or roundover.
19. If there are chips, or gaps in your joints that you cannot live with, fill them with wood dough. LET THE WOOD DOUGH HARDEN THOROUGHLY BEFORE SANDING!! That’s it! Congratulations. Take a break, and when you are ready (maybe tomorrow), we’ll sand and finish the box.
FINISHING THE BOX There are lots of ways to apply a beautiful, durable finish to a solid wood box. Following is how we finish our cabinets here at the Lab. You may finish your Percolator any way you like. Please send us photos of your completed project for our gallery! Your cabinet is made of top-grade solid poplar.
Apply a liberal coat of MinWax Dark Walnut Wood Finish #2716 with a rag. This is an oil- based stain, one of the easiest to use. Coat the entire cabinet inside and out, then wipe it 169, 170 off again with a clean rag. Rub it out thoroughly and carefully, leaving no fingerprints or 171, 172 streaks.
Use a clean rag to apply a coat of MinWax Wpe-On Poly Clear Satin. This is a remarkable product that is thick enough to provide a decent finish, but thin enough to soak straight into the wood without running or dripping. Pour a little product into a disposable metal or plastic cup, like the bottom inch cut from a soda can.
Clean up your work space as best you can. Remove all the dust from the cabinet and the work table. Sweep or vacuum the floor. It is dust in the air that affects the final finish. Apply a second coat of Wipe-On Poly to the exterior. Allow to dry thoroughly. 183, 184 At this point, if the box is beautiful and satiny-smooth, you are done.
ASSEMBLING THE CABINET On the cabinet bottom, install the four little feet (Part # FT03) with four little sheet metal screws #6x5/8” (Part # SC66) into the four little 1/16” holes near the corners. Do not over-tighten. Use a short screw driver to install the handle, using the screws that came with it.
ASSEMBLING THE GRILL Lay out the four wood pieces as shown. Apply a drop of glue to both ends of both long pieces. Spread it out to coat the entire end of the stick. Fit the pieces together and place a bar clamp across the width of the frame. Gently snug the clamp down on the frame just until you see glue squeezing out of all four corners.
Now it is time to put on the grill cloth. Attaching grill cloth in a way that looks nice is not an easy task. There are 2 goals to keep in mind when working with grill cloth: 1) Keep the lines straight; nobody thinks crooked or wavy grill cloth looks good.
b. Place the frame back on the grill cloth (with the long edge against the fold) and line up one of the short sides with one of the black lines on the grill cloth about one inch away from the edge of the cloth.
d. With the frame resting between the 3 folds, find the line that is parallel and closest to remaining short side of the frame. Remove the frame and cut the grill cloth on each of the long-side folds up to this new line. ONCE AGAIN, DON’T OVER CUT. Fold and crease 205, 206 along this line.
Place the assembly face down on the table. While holding the grill cloth in its proper place, use your staple gun to put one staple in the middle of each side of the frame. Make sure the staple is right in the middle of the side in both directions (up/down and left/right). Re-examine the assembly to make sure the grill cloth lines are still straight (use your speed square) and check to make sure the back of the grill cloth is still tight against the face of the...
10. When you are done stapling and the lines are all straight, cut the surplus lengths of the grill cloth from the corners of the frame. 11. Fold the remaining grill cloth over to the back of the frame and staple it down. Leave about 1/2” from the corners without any staples.
13. Use a match or lighter to carefully singe the loose threads at the corners as shown. Move the flame quickly - grill cloth melts very fast. WARNING: Open flames are dangerous, especially around flamable material such as grill cloth and wood. Use common sense. 14.
over the entire area, warming the whole frame evenly. Be patient and take your time, and you should be pleased with the results. 221, 222...
COMPLETING THE HEAD INSTALLING THE AMP Place the cabinet upright on the table and carefully slip the amp in. It should be a pretty nice slide-fit side-to-side. Looks nice, eh? Carefully turn the amp over and stand it on-end, with the bottom facing you. Use one hand to hold the amp firmly in place against the cabinet bottom.
INSTALLING THE GRILL Fit the grill frame into the front of the cabinet, above the amp. Push it in tflush to the cabinet front. It should be an easy fit side-to-side; it may be a tight fit up-and-down. Fit a 1/16” drill bit to stick about 1-1/8” out of your screw gun, or use your combo piloting bit. Center the grill frame left and right.
1M, so most electric guitars and high impedance harp mics will work well with this amp. One of the main things to remember when using the Percolator is to never turn it on without an 8 ohm speaker load plugged into the output jack! The Percolator was designed specifically to be used with the Zeppelin Design Labs 1x8 speaker cabinet (also available in kit form), but you can use any speaker cabinet or combination of speakers you’d like, as long as the sum of the output impedance is 8 ohms.