converting AC to DC?

[jasonober]

I built the Tube Driver from GGG and was planning to use that circuit and a ts-808 in the same enclosure.  however the tube driver runs 12.6 ac (using 13v wall wart) is there a way to easily convert this to 9v dc so i can power both from the same supply or should i use separate supplies?

[R.G.]

Read GEO (http://www.geofex.com).

Preferably all of it, but in this case, start with "Power Supplies Basics".

[jasonober]

well i read Geo's Power Supply Basics     maybe i'm dull but i still don't understand

[Hal]

you need a rectifier, 9v regulator, and large filter caps.  Thats about it.

[jasonober]

I wonder if anyone can elaborate on this?  This is scheme:
http://www.generalguitargadgets.com/diagrams/tube_driver_sc.gif

Help would really be appreciated.  I'm still really new to this, prior to this project I've only built a LPB and a mini booster.  Thanks

[jasonober]

I wonder if i can just tap cathode pins 3,8
Is that what is suggested here

Peter Snowberg
The easiest way would be to drop the filament supply to 9V using an LM7809 or an LM317, but you might also want to see what the TS sounds like with a 12V supply.  

Does the tube driver use a DC supply for the filaments?
It will have no problems with the extra voltage and the only side effect will be a slightly modified tone which you may like better or worse. Don't you love those ambiguous answers?  

Yes, the filaments are running from DC.

Build away!

[Paul Perry (Frostwave)]

If you want +9 volts, just take the + on JD Sleep's ckt & run to a 3 terminal 9v regulator.
Confusingly, JD doesn't seem to have put the filament connections in!

[jasonober]

If you want +9 volts, just take the + on JD Sleep's ckt & run to a 3 terminal 9v regulator.
Confusingly, JD doesn't seem to have put the filament connections in!

Will this work?
http://www.njr.co.jp/pdf/ae/ae06004.pdf

if so how do I use it?  thanks for the help

[Peter Snowberg]

A 78L09 will work perfectly for powering pedals....

See the datasheet page 6 for an example of use.

There are also examples all over the web. This is a family of different regulators, but they all work the same. You'll get lots of results if you search for '7805 power supply' because you find these things all over digital logic circuits from everywhere. The 7812 is probably the next most common. 7809s can be hard to come by if you're not ordering from a large distributor.

These parts are pretty generic.... just put a big cap (say maybe 220uF) at the DC input to ground and put a 0.1µF cap across that cap in parallel for best noise peformance. Put another 0.1µF cap from the output to ground and there you go. Instant regulated 9VDC.

Just keep in mind that these types of regulators want at last 2 volts more than the output voltage. 3 volts is the usual spec.

[jasonober]

Thanks for the help!!!!

Do I get the plus voltage where power enters the board from tranformer or should it come from V+ from after C15? sorry for so many (probably basic) questions!
http://www.generalguitargadgets.com/diagrams/tube_driver_sc.gif

http://www.generalguitargadgets.com/diagrams/tube_driver_lo.gif

[Peter Snowberg]

No problem.

This place exists to ask questions. Please don't be sorry.... ask more questions!

Thanks for including the link to the schematic you're using. That really helps.

You are correct.... take a line from C15 and bring that to Vin of the regulator. Add a small cap (0.1µF to 1µF) across the regulator input and ground, but do it right at the regulator so that lead lengths are minimized. Do the same with a 0.1µF film cap across the output and ground. The little caps eat the bulk of the noise generated in the regulation process so that the regulator can output a stable voltage.

[Paul Perry (Frostwave)]

For the 9v reg, I'd use a LM7809 in a TO-220 case (those flat rectangular packs with a metal tab at one end with a hole in it) because, they can handle more current. In fact they will handle anything except being reversed.
for example Mouser part # 512-MC7809CT

[jasonober]

that's exactly what i ordered from mouser today along with the parts for TS.  just to clarify I'm going to tap tube driver circuit at C15 and that is going to go to input of regulator with 220uf in parallel with .1uf to ground and the output will go into TS as usual with a .1uf to ground of regulator?


I hope i understand this right.  I truly appreciate all the help and anticipate getting this project done as I'm very happy with the Tube Driver(much better than tube works tube driver) and have (I think) a pretty good plan for the enclosure graphics.

[jasonober]

Is this right?   thanks!

[Paul Perry (Frostwave)]

Looks right to me, but I only just woke up..