Tube boost + overdrive running off a 9 volt battery

[mth5044]

Ah that .pdf file is wonderful. Thanks for answering everything to promptly.

I think I'm going to go with this twincaster schematic
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Twincaster+rev+0_11.jpg.html

with the R1 pulldown on the second half, seeing as that one fellow had quite a bit of trouble. I am also thinking about adding a switch to cut in and out the second tube. What if I take a SPDT on/on switch, wire C3a to the middle lug, a wire on another lug going V2a where it usually connects then on the other lug, a wire between C3b and C4? I believe that would make it so in one switch direction it would make it like the regular valvecaster then the other way it would be a twincaster.

As for the booster, I'm a poor college student so ordering and building a bunch of different boosters will have to loose out to getting more grocerys  So of the people that have put boosters before, what ones sound best? I play a strat and LP into my 2watt gilmour jr (which is a bit darker to begin with) with whatever effects inbetween.

Also, would it be a good idea to put an on/off switch in the back or something to get the tubes to warm up? Kind of like a standby?

Final question of the post - That fixed voltage regulator, is it necessary? It seems that adding that and then a heatsink would take up a lot of room (even though I'm planning on building it in a large enclosure anyway).

[Jimmy-H]

A.  Also, would it be a good idea to put an on/off switch in the back or something to get the tubes to warm up? Kind of like a standby?


B. Final question of the post - That fixed voltage regulator, is it necessary? It seems that adding that and then a heatsink would take up a lot of room (even though I'm planning on building it in a large enclosure anyway).

A. I don't think it is necessary, no one did it anyway.

B. It's only necessary if you have a bad regulated and filtered power supply.
    I used an old printer (switching)power supply.
success with your build!

[served]

I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?

I actually built Pepper Shredder, but its the same deal.

[frequencycentral]

I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?

I actually built Pepper Shredder, but its the same deal.

Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine

[mth5044]

I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?

I actually built Pepper Shredder, but its the same deal.

Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine

So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?

Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26

I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too 

[frequencycentral]

I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?

I actually built Pepper Shredder, but its the same deal.

Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine

So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?

Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26

I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too 

I would guess the Stratoblaster should run on 12 volts, but as its a JFET you may need to re-bias it for 12 volts by changing R2. I think the process would be to build and test the SB at 9 volts, measure the voltage at the JFET's 'Drain', power it up at 12 volts and use a trimpot to replicate the voltage at the JET's 'Drain'.

Alternatively, I built a LPB into my second Valvecaster, and didn't do anything at all about the voltage change! So - it might work out just fine without doing a thing to it - just give a little more gain maybe........

[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

Are you referring to this dialogue between ambulancevoice and Renegadrian?
http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550659#msg550659

I'll add this note to the summary.

Thanks!
-bK

[snap]

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

Are you referring to this dialogue between ambulancevoice and Renegadrian?
http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550659#msg550659

I'll add this note to the summary.

Thanks!
-bK

http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550722#msg550722
similar is true for FET gates: don`t let them float.

[mth5044]

I added a DPDT switch in there between C3 and the new R1. Once you cut out the second tube, it should be exactly like a valvecaster right? Am I missing anything big here? Is there going to be an awful pop or something with the switch is engaged?

I'm going to add in a two color LED to the other side of the DPDT to show what tubes are being used. I found a 3 color LED while searching for the two color one. Is it bad if I want to build something just to use a three color LED   

[kurtlives]

Put the final connection of the switch before the last coupling "blocking" cap (C3).

[mth5044]

You mean the one right before the tone pot setup? If I did that, would that make 2 C3's in a row?

[snap]

yes, it will pop, and bytheway there are already 2 C3`s in that schematic ?

[Franky]

The names are not that important, but BTW yeah, it's a little bit confusing..

To put both C3 in series by switching will definitely pop out..

Anyway, are you sure of that wiring for your 1M R1(bis) resistor, right after the switch? Isn't that supposed to go from the plate to the ground?


Good idea about the LEDs, I'm planning to put some RGB automatically color changing in my tubes sockets.. Cool effect.. 

[mth5044]

based on my inferior knowledge of the recomendations, here is an updated schematic. I added a's and b's so hopefully it wont be as confusing, changed R1b and put the switch before C3b, although that doesnt make too much sense to me.

If there is no way to solve the popping part, I guess ill just build two valvecasters but use dual pots for the tone and volume. Pretty much the same thing I guess.

[Renegadrian]

So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?

Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26

I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too 

I would guess the Stratoblaster should run on 12 volts, but as its a JFET you may need to re-bias it for 12 volts by changing R2. I think the process would be to build and test the SB at 9 volts, measure the voltage at the JFET's 'Drain', power it up at 12 volts and use a trimpot to replicate the voltage at the JET's 'Drain'.

Alternatively, I built a LPB into my second Valvecaster, and didn't do anything at all about the voltage change! So - it might work out just fine without doing a thing to it - just give a little more gain maybe........

Either you could use a 9AU7 tube, which is the 9v version of the 12AU7...use a 7809 if you need a regulated v and run both fx at the standard 9v. I'd say 500mA or more as for the wall wart, try 300mA too but the more the better I believe.

[snap]

for less popping, add another 1M from the righthandside of C3a to ground.

[frequencycentral]

It might be best to uses a DPDT switch to isolate the second Valvecaster from the output.

[mth5044]

I think I'm just going to do it so that there are technically two valvecasters in one box, rather then going for a switchable twincaster. So it will go stratobooster -> valvecaster which when turned on will take to to the switch for the second valvecaster, and when off will take it to the out. That way when I want to go from 2 valvecasters to none, I'll only have to hit one switch. Then the second valvcaster switch will go to the out also. Kind of like this (sorry about the huge picture, my photoshop skills are lacking):

VC1 and VC2 are valvecaster 1 and 2 and the two left sides of both switches reserved for LED indicators. Should I ground the 2nd lug on the third horizontal row on the VC1 switch? Usually not grounding something screws me over so I thought I'd ask.

\I'm also debating if I want to go with the dualgang volume and tone pots or do seperate ones for each. I like the dual gang for the less clutter, but I'm one for versitility, so maybe combining using two volumes and tones at the same time would be cool, like combining different tones and volumes on the middle switch of a les paul. I think I've got a pretty good layout design too, just need to see if pedalpartsplus can drill holes for tube sockets 

Thanks again for your help.

[served]

Hey. Im starting to build that  circuit for fixed voltage. Is it wise to use one power supply and add two regulators to it? 12V and 9V? Is it wise to save some parts and put 7812 and 7809 parallel after 0.1uF and 470uF, but all that is after the regulator is independent, 7812 is with its own 3 caps to output and 7809 has its own?
I hope you ll understand what i mean.

[Renegadrian]

I didn't get what you mean...Do you want it to be powered at 9v or 12v?
You have to use either 7809 or 7812, depending on the choice above...
Else I don't see the need of 2 regulators...