Tube boost + overdrive running off a 9 volt battery

[served]

Ill build a powersupply for my pedals. All the transistor based pedals use 9V so i need it too. Guess it wont change anything if i put two 78xxs like i wanted. The point is, why do i have to waste 1x0.1uF and 1x470uF if i can keep thouse.

[tranceracer]

In that summary on page 4 the Dual Valve Casters schematic 3. triode still missing a gridleak resistor.
http://www.diystompboxes.com/smfforum/index.php?topic=68759.0

Revised summary:

http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf
Includes the 'caster's 2nd 1Meg Resistor and the schematic and discussions re: the switch mod.

Thanks!  (:
-bK

[c.wright]

Hmmm.... Ok - hi -  long time lurker - very rare post-er....

Here's the kind of problem you LOVE:
"Model-builder with lousy parts and barely passable solder skills seeks help with HUM."

First, apologies if I missed something in the 38+ pages, I have tried to read it all thoroughly.
I'm just hoping for some general advice before I scrap this one and re-build from scratch.

Massive hum problem - but the circuit boosts and distorts freaking GREAT.

Built the 7812 power regulator.
Caught a an ungrounded lug on a pot - that fixed some of the hum.
Caught a silly mistake, when I used a NP cap for C3 (the DC blocking cap, correct?)
BUT - that didn't seem to fix the problem at all.
Tried 3 12AU7s, 12AV7, 12AT7
Also, have tried 6v 500ma, 9v 200ma, 9v 500ma, 12v 500ma - all wallwarts, all hum. Higher voltage = more hum.
And OF COURSE, those are all QUALITY parts (sarcasm here), from various telephones, answering machines, baby monitors etc.

Here is where it all went off the tracks - I initially had my stupid DC wiring backwards (CANNOT get my mind around a negative tip. Call me wet behind the ears, I don't mind)  and so I'm wondering if I cooked something? The weird thing is, the circuit seems to work very well - just very very loud hum. Used to be as loud as the guitar signal, but the regulator and fixed grounding issue reduced the hum by about 50%
It's just on the verge of being usable now.
I'm not concerned about hiss, buzz, or any other noisy racket - just this loud HUM.

NOW - I'm getting about 4 VDC on the output! (surprised?)
So that means blocking cap (C3) and/or resistor (R3), right?! Or something else?
Could it be that every 1uF cap that I own (about 6, all salvage) doesn't work?
Could it be that my soldering skills demonstrate borderline dementia?
Did I mention the incredible quality of salvaged parts I'm using?
...actually, all but the 1uf were new parts... except the tube(s)... and the socket... and the jacks...

SO. Scrap it and start again (with newer parts) or is it salvagable?


Again, apologies if I shoulda started a new post or something, I do a LOT of reading, but not much posting. Prefer to keep my mouth shut when I don't know what I'm talking about.
Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.

[frequencycentral]

Hmmm.... Ok - hi -  long time lurker - very rare post-er....

Here's the kind of problem you LOVE:
"Model-builder with lousy parts and barely passable solder skills seeks help with HUM."

First, apologies if I missed something in the 38+ pages, I have tried to read it all thoroughly.
I'm just hoping for some general advice before I scrap this one and re-build from scratch.

Massive hum problem - but the circuit boosts and distorts freaking GREAT.

Built the 7812 power regulator.
Caught a an ungrounded lug on a pot - that fixed some of the hum.
Caught a silly mistake, when I used a NP cap for C3 (the DC blocking cap, correct?)
BUT - that didn't seem to fix the problem at all.
Tried 3 12AU7s, 12AV7, 12AT7
Also, have tried 6v 500ma, 9v 200ma, 9v 500ma, 12v 500ma - all wallwarts, all hum. Higher voltage = more hum.
And OF COURSE, those are all QUALITY parts (sarcasm here), from various telephones, answering machines, baby monitors etc.

Here is where it all went off the tracks - I initially had my stupid DC wiring backwards (CANNOT get my mind around a negative tip. Call me wet behind the ears, I don't mind)  and so I'm wondering if I cooked something? The weird thing is, the circuit seems to work very well - just very very loud hum. Used to be as loud as the guitar signal, but the regulator and fixed grounding issue reduced the hum by about 50%
It's just on the verge of being usable now.
I'm not concerned about hiss, buzz, or any other noisy racket - just this loud HUM.

NOW - I'm getting about 4 VDC on the output! (surprised?)
So that means blocking cap (C3) and/or resistor (R3), right?! Or something else?
Could it be that every 1uF cap that I own (about 6, all salvage) doesn't work?
Could it be that my soldering skills demonstrate borderline dementia?
Did I mention the incredible quality of salvaged parts I'm using?
...actually, all but the 1uf were new parts... except the tube(s)... and the socket... and the jacks...

SO. Scrap it and start again (with newer parts) or is it salvagable?


Again, apologies if I shoulda started a new post or something, I do a LOT of reading, but not much posting. Prefer to keep my mouth shut when I don't know what I'm talking about.
Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.

Hi Chris! Test your voltages and post them here.

Here's mine, running at 12 volts:

Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v

[Renegadrian]

Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.

we'd say it's better for you to stay, but even if you don't you gotta have your valvy up and running silently...

C3 (1µF) can be P or NP, I used them both...

[c.wright]

WOW. You guys are FAST.

OK, here's my numbers from 2 different wallwarts:

12v 500ma (meters at 17.5v)

1.   11.65
2.   -0.491
3.   0
4.   0
5.   13.42
6.   8.96
7.   -0.534
8.   0

9v 300ma (meters at 15v)

1.  9.86
2.  -0.335
3.  0
4.  0
5.  11.14
6.  8.02
7.  -0.330
8.  0

(pesky numbers - in my perfect world, all science is based on COLORS...)

Soooooo.... since my pin 1 is off the charts, am I to assume that my 220K (R2) is cooked, shorted, cold-jointed or otherwise?

Man, i was all proud thinking i'd troubleshot that C3 and now you blow it for me Renegadrian!! 
I'da thought a blocking cap would need to only let stuff go one-way?
Welp, showing my ignorance here.
I've built about 40 projects, and I'd say my hit/miss ratio is a good 60/40!
- I can build models & puzzles real good, but I'm only so-so on the theory.

Thanks again for the quick replies, and thanks in advance for the help!

[frequencycentral]

12v 500ma (meters at 17.5v)

1.   11.65
2.   -0.491
3.   0
4.   0
5.   13.42
6.   8.96
7.   -0.534
8.   0

Soooooo.... since my pin 1 is off the charts, am I to assume that my 220K (R2) is cooked, shorted, cold-jointed or otherwise?

Thanks again for the quick replies, and thanks in advance for the help!

Yup, it's pin 1 that's the problem as you correctly identifed! Check the resistor with your meter for ohmage/continuity. And shorts, cold-joints or otherwise!

All the other voltages look good, but your 12 volts DC looks like its actually 13.42 volts, judging from pin 5. I think that may still be within the heater tolerance, but it would be worth you checking that out on a 12AU7 data sheet. It might be overheating the heater! Ideally the heater wants 12.6 volts, though 12 volts would be fine.

Good luck!

Rick

[Renegadrian]

WOW. You guys are FAST.

Man, i was all proud thinking i'd troubleshot that C3 and now you blow it for me Renegadrian!! 
I'da thought a blocking cap would need to only let stuff go one-way?

Thanks again for the quick replies, and thanks in advance for the help!

Look where the question comes from...
It's a P in the schem but a NP in the wiring layout---



And read that I've been thru the same doubt...
http://www.diystompboxes.com/smfforum/index.php?topic=63479.180

So no, that's not the issue...I've used both and don't find such a difference...

[mth5044]

Hey man, post some sound clips when you get it all worked out. I love listening to these thing.

I can't wait to get mine up and running. Two valvecaster and a booster, but I can't quite deside on the booster. I was going to do the stratoblaster, but someone said the SHO was good infront of it. I read they were noisy though. Any other easy, simple, CLEAN booster that have been tested good with this thing?

[frequencycentral]

Hey man, post some sound clips when you get it all worked out. I love listening to these thing.

I can't wait to get mine up and running. Two valvecaster and a booster, but I can't quite deside on the booster. I was going to do the stratoblaster, but someone said the SHO was good infront of it. I read they were noisy though. Any other easy, simple, CLEAN booster that have been tested good with this thing?

PentaBoost

[frequencycentral]

Where do you generally have your Valvecaster "Volume" control set?

If you're anything like me, then you like gain, dirt and crunch.

That means setting the Gain pot high and the Volume pot low - right?

So, if the volume pot is set to 25% that's 75K of serial resistance cutting away at your treble.

Jeez - no wonder this circuit has the reputation of sounding a little 'dark'!

When I set up the plate resistors on my Vibracaster I set it up for unity gain between the bypassed and effected signals - it doesn't suffer from 'darkness' like the Valvecaster does - no volume control > no serial resistance dragging away the highs.

I'm gonna bridge my 100K Volume pot with a 10K resistor, it will mean I can't use the Valvecaster as a clean boost - but hey, I'll just build me a PentaBoost instead.

[mth5044]

Man, did you just write an add for your pentaboost? I imagined it being like a child in a cereal commercial. 

I will have to check into your pentaboost. Thanks.

edit: oh man, just read about the pentaboost. I think it will do lovely in the same box with two valvecasters. Have you tried it as a boost before the 12au7 type valvecasters?

Plus now I can tell people its an 'all tube' unit. 

how do you mount them buggers anyway? I was going to put the 12AU7's out the top, so I would like to have the little guy sticking out there to.

[frequencycentral]

Man, did you just write an add for your pentaboost? I imagined it being like a child in a cereal commercial. 

I will have to check into your pentaboost. Thanks.

Q:"How do you keep your teeth so shiny and white?"

A: "I only use 'PentaBoost' when I brush!"

or

"Take two bottles into the shower? Shampoo and conditioner? Not me - I just take 'PentaBoost'....."

or

"Tired of dull, lifeless guitar riffs.......?"

You get the picture! Always room for humour and shameless self-promotion around here...........

[c.wright]

Look where the question comes from...
It's a P in the schem but a NP in the wiring layout---

And read that I've been thru the same doubt...
http://www.diystompboxes.com/smfforum/index.php?topic=63479.180

So no, that's not the issue...I've used both and don't find such a difference...

Hah - Adriano, I wish I was that astute and could blame the discrepancy for my mix-up, but really i just wrote out a quick manifest and started slapping it together based on the layout... I didn't reference the actual schematic until I started having problems! Hey, like I said, I'm a model-builder...
---
SO, I had to break for dinner and all that (wives really like it when you put down the iron and the guitar) - but I did go back over my stuff, and checked R2, and my solder joints.

The resistor metered ok, the connections are all iffy though. Since it was a first-time build for me, i used an old socket I got from Mendelson's here in Dayton, and the thing was crusty and weird and sacrifice-able ... in retrospect, this sort of logic is probably 90% of my problems...
Also, I crammed all my parts onto the backside of that socket as close as I could get them for the sake of being compact. That might not be good either.

So, geez, you know, I could keep beating this thing to death, but it's like, EIGHT freakin PARTS?!
So I'm gonna start a new one from scratch tonight - now that i've got a 'proof of concept' build done, I'll use a NEW socket, and everything else NEW too!!!

Thank you Rick and Adriano, I really appreciate the help, and I'll try to get some kind of sound clips posted after I get the new one done!

many thanks -

[Renegadrian]

Right Chris, post your results when done, ok?! 

[kurtlives]

I don't know if you guys remember but I built mine then the gain pot stopped working. Turns out the actual pot went bad...never had that happen. O well on a simple circuit like this that I understand it wasn't too hard to track it down.

Stock circuit minus a 33nF input cap... I don't find this circuit dark at all. Though I always have liked and have a slightly bright stock tone. Nice boost/OD.





A great little circuit, great fun to play with.

[cheeb]

Looks great!

[andrew_k]

Great font choice man, looks professional 

Where can I get some of those knobs from? I've got a pedal underway that they'd be perfect for... thanks!

[Renegadrian]

Andrew, I know Banzai got them ---------->
They are german based, I don't know if your trusty retailer got them...Else go buy them thru Banzai...

[Franky]

Looks great! Is that an etched design?