Tube boost + overdrive running off a 9 volt battery

[sundgist]

Finally got this boxed up. Built the main board a year ago and have just been adding and changing bits since then.

Valvecaster running on 48v with switchable tremolo. 12ax7 in there at the moment.
No stomp switch as it is the last in the chain and pretty much stays on.
Sounds great in front of my clean SS amp especially when being pushed by a booster.



3 gain modes, clean, dirty and treble boost.



And the guts.
Havn't decided whether to mount the regulator inside the box yet.
Gets quite hot but as the tab on the ic connected to the voltage output pin I can't think how to bolt it to the enclosure but keep it insulated.

[Renegadrian]

Nice, you used this Voltage Multiplier!!!

[sundgist]

Nice, you used this Voltage Multiplier!!!

Yes, it works really nicely.

I posted a vero layout for it further on in that thread. Simple multiplier using common parts.

[carboncomp]

Having real trouble getting my one to work, have breadboared it up and get no effect, just noise as if somethings not grounded.......for what its worth, these are my voltages.

Im using a 5963 PHILIPS ECG

1: 2.5
2:0
3:0
4:0
5:2.5
6:0
7:0
8:0
9:1.2

[iccaros]

your heater voltages are way too low, what power supply are you using?

[carboncomp]

Just a greencell 9v battery

[iccaros]

depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v

Pins 3 and 8 should be close to zero.

do you have pictures we can see and any changes you may have made.

but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)

[carboncomp]

depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v

Pins 3 and 8 should be close to zero.

do you have pictures we can see and any changes you may have made.

but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)

OK rebuilt the hole thing on the breadboard with fresh parts and a new battery, here are the measurements

9v battery @ 8.77v

Tube out

1: 8.57
2:0
3:0
4:0
5: 8.57
6:0
7:0
8:0
9:0

Tube In

1: 7.01
2:0
3:0
4:0
5: 7.01
6: 3.51
7:0
8:0
9: 3.47

Now getting a hint of signal (not even close to unity), but still lots of noise? 

[mth5044]

Sundgist that looks fantastic!

What is that awesome lightening bolt knob on your breadboard?

[nexekho]

Just saw this post, WOW o_0

This image on the front page intrigues me:


If I built that, exactly as shown, and plugged it in, would it work?  Some show a "heater" but the simplicity and safety(?) of this design are really appealing.  Does it take a while to warm up before working?  Does it get hot while running?

[tasos]

If I built that, exactly as shown, and plugged it in, would it work?  Some show a "heater" but the simplicity and safety(?) of this design are really appealing.  Does it take a while to warm up before working?  Does it get hot while running?

Yes it would totally work....
It is not dangerous at these voltages...
It takes about ten seconds to warm up...
And finally,it gets a little hot while running but nothing great!you can even touch the tube...

[nexekho]

AWESOME, thanks.  Next project once my current distortion is complete will probably be one of these to replace the op-amp booster I'm using.

[iccaros]

depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v

Pins 3 and 8 should be close to zero.

do you have pictures we can see and any changes you may have made.

but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)

OK rebuilt the hole thing on the breadboard with fresh parts and a new battery, here are the measurements

9v battery @ 8.77v

Tube out

1: 8.57
2:0
3:0
4:0
5: 8.57
6:0
7:0
8:0
9:0

Tube In

1: 7.01
2:0
3:0
4:0
5: 7.01
6: 3.51
7:0
8:0
9: 3.47

Now getting a hint of signal (not even close to unity), but still lots of noise? 

check your wiring to pin 6, that is a plate and should have voltage on it.....

[carboncomp]

Still having a nightmare with this!

I used this vero layout and still get no effect



Even had a friend play with it who know far more then me, and he had no luck?


Is there any way to test if its the valve thats faulty?

also was testing with unity on my DDM to make sure all the pins where wired right and noticed i get unity betwwn the + and - tracks on my breadboard then the valve in in the socket.....that can be right, can it?

[Renegadrian]

Are the resistors all in the right place?! The two on the right should use 4 rows right?! Also did you remember to cut the track under the first cap!? I guess you should get some sound anyway...did you check pins orientation!? Does pin 5 get voltage?! Check pin 4 and 5 with the DMM...Does the tube glow!? if yes, it gets the heater voltage...

[carboncomp]

Are the resistors all in the right place?! The two on the right should use 4 rows right?! Also did you remember to cut the track under the first cap!? I guess you should get some sound anyway...did you check pins orientation!? Does pin 5 get voltage?! Check pin 4 and 5 with the DMM...Does the tube glow!? if yes, it gets the heater voltage...

Yes, resister have been checked a hundret times, track is cut and tested with DMM, This is the pin orientation iv been using......am I about to get egg on my face?


here are the voltages

tube out
1: 7.79
2:
3:
4:
5: 8.00
6  7.97
7
8
9

tube in
1: 4.91
2:
3:
4:
5: 5.88
6  4.47
7:
8:
9: 2.89

and the plus and minus track are still making my DMM beep in diode mode, when the tube is in??

[iccaros]

voltages look better, but low.. Do you have another tube to test with?  if you look in http://www.diystompboxes.com/smfforum/index.php?topic=29816.0 they show how to make an audio probe to help trouble shoot...

as for testing a tube, well you can measure signal level with a DMM, its not the best, but put a known signal in and measure the AC voltage on say pin 2. then measure AC on Pin 7 you should see gain...

when the tube is in the heaters will look like a short to the DMM so you will get the beep.. as it increases resistance as it heats, and the DMM is not enough to make it heat up

your c3 is polarized? I would not use a polarized cap for that..

[Renegadrian]

Tube socket pins are numbered correctly, I disagree about the the c3 cap, an electro can be used with good results, with the - to the pot as is in your picture. Apart from the first one, all the others I built have an electro.

[zambo]

+ 1 on c3 electro. i always use one for c3.

[carboncomp]

voltages look better, but low.. Do you have another tube to test with? 

No I dont, guess I better order one

just checked everything, cap and resister values, pin out put, even the tracks on my breadboard.

Plugged it into my larger amp, and get a faint sound, and can here changes in the volume and gain knob......but its a whisper even with the amp at 11.