Any body out there have a PCB layout for the Matchless Hotbox? My band's lead singer wants me to build him a clone. I have the schems and know how to breadboard, just figured i'd check here first.
Hmmm... not sure I have ever seen a layout. However, it's a relatively simple build. I usually build things directly from a schematic and let the layout be whatever it is. As long as all the right points are connected you're good.
Be careful on this one because it does use a high voltage on the plates :)
Have fun.
He wants this as a pedal. Told him this was a schem for an amp, not a pedal. Not sure if anyone has tried to design the circuit to go in a pedal enclosure.
It actually *was* a pedal. Big one though, but it came with it's own footswitch on the box and everything.
It does carry high voltage - if you have any doubt whatsoever on dealing with that - don't. DC at tube plate voltages can and will kill, potentially even when the unit isn't plugged in.
Knowing Matchless this thing was built pojnt-to-point. Turretstrip is probably the easiest way, and incredibly sturdy too.
hih
Thanx for the info. I assumed it was an amp because of the voltage level and the tubes. Never built an amp before, just pedals. Not sure I want to attack this one. The schem doesn't look that hard, and I figured it was probably point to point, but the voltage level kinda frightens me. I might decide to try it eventually.
It is a point to point wired unit, runs on 110V. Great unit, high gain, although tends to add a lot of brightness. It is never really bypassed; it has two channels, like an amp: clean and dirty. There is no indicator (other than screaming distortion) to tell you which channel is on. It is big, 1/8" chromed steel chassis, weighs a ton.
But to answer the initial question, there is no PCB layout as it has no PCB!
Here's a link to JD. Sleep's site with schematic, bill of materials and an eyelet/turret board layout. As Mike Burgundy mentioned, you could just use turretstrips or even Terminal strips instead of a board.
http://www.generalguitargadgets.com/projects/17-distortion/96-hotbox
Hoffman Amps actually has a Tube pedal chassis that looks like it would work for this as it has hole for 2 tubes and a metal guard for the tubes.
(Scroll down to about the middle of the page)
http://www.hoffmanamps.com/MyStore/perlshop.cgi?action=template&thispage=Chassis&ORDER_ID=286411742
It does run at high voltages though....
I have had some pretty good luck building high voltage designs and then just undervolting them actualy. You might try to build one and use just a simple voltage doubler so you can use a 12volt dc walwart for the heaters and then run the doubler leads to the plates at 24. I may not sound like the actual hot box but it might sound really good... I will try to build the low voltage version for fun. I need more caps.... :icon_sad:
Why not go this route ?
http://www.diystompboxes.com/smfforum/index.php?topic=46806.0
ROG J-Fet emu amps can be great and give the "Flavor" of the real thing, you may need to make a few adjustments
for the "Hotbox" version.
MM.
Damn. Didn't even think of checking at GGG. I've never built anything with tubes yet. Kinda been shying away from it because of my lack if experience with tubes. I just finished the Dr.Boogey layout from Atlantic PCB (gaussmarkov) and still have to bias it. Might tackle the Matchless next.
Another first for me is biasing. Can I assume it is similar to biasing the channels on an old 2", 24 track tape machine?