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The rule of thumb is that the load impedance of a power tube is roughly 1/10th that of the plate resistance. The data sheets regarding that tube type don't specify a load resistance. I would say an OT with a primary of 4Kohms would be a good start. If you're going PP, use a transformer that has a primary impedance of 8K center tapped. Each output tube should see its respective appropriate load. In other words, each tube should only be presented with the appropriate amount of current, which is limited by the output transformer, along with any plate resistors, which I don't use with space charge tubes.

Edit: Bah! I meant CATHODE resistors! Don't drink and type, kids!
Is this your Palomino V32? I'd have to stick a 'scope on it, but my first guess is that perhaps one of the op-amps in the reverb circuit is faulty, maybe oscillating. Op-amps can behave erratically depending on ambient temperature. I don't think it's the reverb tank itself. One step beyond cleaning connections would be to ensure that the connections to and from the reverb tank are intact using an ohm meter.

All in all, I'm suspicious of those op-amps.
If you connect it according to the diagram, it will work. You must have it connected improperly. Pics?
Of course, what are you using to turn it "on?"

"Larger values will yield less treble content." There's nothing more to it. It's a treble bleed. The higher the value, the less treble will get through, and vice versa.

Sure, switch the supply, switch the signal, switch both... whatever you want.

Not really. Learn more about what each component does, and then how they work together in the circuit.
Dark stain with 10 coats of gloss clear.
Does the wah pedal you bought have a pot in it? You could try using that. As far as connecting to your effects pedal, I'm guessing all you'll need is a mono 1/4" plug. It depends on the effects pedal, however. Attempting this shouldn't wreck your pedal. Simply connect a two conductor cable between a 1/4" plug and the pot.

It would help us a lot more if you could list the brand and model of effects pedal you're using.
It depends on what the effects pedal requires. I would think the only requirement is a pot, in which case, any wah/expression pedal could suffice.
You guys missed a clue. If it was a rectifier, the volume of the buzzing would still change with the volume pot. I'm thinking the amplifier chip is shot. And I just had to laugh... "quite small, about the size of a 100 watt resistor." LOL
But then you'll also be cancelling the wet signal, which will also be 180 degrees out of phase with the "boosted" signal. I'd have to see the signals on an o'scope. Can you post some pics of the wave forms after it's operational? I prefer using volume pots on each gain stage, myself. A boost switch is only useful for switching between rhythm/lead sound, and can be accomplished with a simple cathode capacitor switch. But hey, whatever strangles your goose
Did you solder the end (opposite the hot) pot lugs to ground?
I think they're basswood... only one place I found listed them as alder.

Yeah, if you can get it for $100 or less, do it. Definitely provide it with some decent quality humbuckers and electronics. Also want to replace the bridge and tuners. According to reviews, these guitars had trouble staying in tune. I think it would be a good foundation for beginning modders.
Or, you could use an adapter. That pedal is made to run on 12VDC. If you use an adapter, you wouldn't have to worry about batteries.
Jim, he's talking about adding a 4 X 10. The amp is a 2 X 10. If the extension cabinet's total impedance is mismatched, damage could occur.
Just a question about the boost section. Isn't it more of a cut section? The signal goes into V2, which is both triodes connected in parallel. Then, the signal with the boost switch gets fed back to V3A. V2 is going to invert the signal. V3B is providing double duty: amplifying the wet signal, and inverting the signal again, so it adds to the dry signal instead of subtracting from it.

Am I understanding the circuit correctly?
Does the level pot work? Do you hear any effect at all, or just a dry signal?

Edit: After reading the instructions, I would try replacing the battery. The circuit is designed to run on 12 volts, and 7 is probably too low.
We need to know the output impedance of the amp, as well as the impedance of each speaker. The speakers can be wired in different configurations to change load impedance, but it must match the amp's output impedance requirements.
It doesn't matter in what order the tone pot and cap are connected to the rest of the circuit. It just needs to be connected in parallel with the output, so it can cut high frequencies to ground. Potentiometers are variable resistors. Resistors RESIST the flow of electrical current. Capacitors, depending on value, pass only higher frequencies. So together, the pot and cap form a filter. Depending on the resistor's value (pot position), more or less of the signal's higher frequencies will be routed to ground.

Go to this page and read up: https://www.ultimate-guitar.com/forum/showthread.php?t=547959
Cool sites. I have a medium-size aluminum rack my employer threw away... perfect condition. The only rack-mount equipment I have, though, is a crappy old ASI mixer/amp unit we used when we started gigging in HS. Building your own sounds like fun!
12U7: http://store.tubedepot.com/nos-12u7.html

Reading material: http://www.sophtamps.ca/mambo/index.php?option=com_content&task=view&id=25&Itemid=37

As far as the PP design, I just used conventional tube designs and tweaked while powered up. That's the advantage to low voltage circuits: being able to replace component values without shocking yourself or destroying a tube. And if you do wreck a tube, who cares? They're $6.

Match the OT to the recommended tube load.
I hate it when something begins to work again without determining the root cause(s). Can't learn much when that happens. Congrats, anyway!
Quote by kurtlives91


What would happen if a power tube was put in it's socket the wrong way?



Aren't your sockets keyed?

Define "wrong way." Look at the pinout diagram, and determine what would happen if the wrong pins are inserted into the sockets.
LOL SYK! Burned wire = short, period. Somewhere, your filament circuit is shorted. Check with an ohm meter.

I highly doubt it is the PT, but check each winding's continuity anyway, making sure each separate winding is isolated from the rest as well as the transformer case.
I'm also interested in your project, jewbaby667. It would require quite a few 12K5 tubes to produce 1W output. Each tube is only rated for about 40mW. You would need a hefty battery to provide enough current to power all of those heaters.

I think you're better off sticking with what you've come up with so far. Please post pictures following your progress. Good luck, and learn much!
As far as perf boards go, try using plated-through type. The pads don't lift as easily.

https://www.alliedelec.com/Search/ProductDetail.aspx?SKU=2370119&MPN=8000-45&R=2370119&SEARCH=2370119&DESC=8000-45

I get ones like these and then cut to size.
Try checking the continuity of the breaker with an ohm meter.

FYI: You have your alligator clips connected to the negative side of the cap. It's not discharging anything, unless it's a positive ground amp

If the amp doesn't power up at all, it's 99.9% unlikely the chip has anything to do with it.

What diode are you guys referring to?
The "push to reset" switch is a breaker. If it doesn't stay in, it's broken. That's probably your problem.

WTF is with the alligator clip?

Are the new caps part of the H.V. power supply filtering? I would think that a cap rated for that low of voltage would have exploded a long time ago if that was the case. Either that, or the power supply's voltage was reduced.
Those shoe straps only work if the floor you're walking on is coated in conductive wax. A wrist strap connected to metal water pipes or the ground socket of a receptacle will do it, too. Standing in mud with bare feet will also work.
Go here: http://www.ax84.com/
Read and learn as much as you can. They cover just about everything having to do with tube amps. In order to attain your goal, you require some fundamentals first.
You could also drive a reed relay, which would last longer than a mechanical relay, and probably be less noisy: http://www.hamlin.com/product-group.cfm?prodcatid=3
Use a 555 timer circuit in astable mode: http://home.cogeco.ca/~rpaisley4/LM555.html#3
that turns on and off either an optocoupler: http://en.wikipedia.org/wiki/Opto-isolator
or an SSR: http://en.wikipedia.org/wiki/Solid_state_relay
that switches your effect loop on and off.
I like these ideas. Build your own analog effects processor. Beat Z. Vex at his own game