XenoSonic Construction / Troubleshooting / Tesla Coils / Forums

Forums

4hv.org :: Forums :: Tesla Coils

« Previous topic | Next topic »

XenoSonic Construction / Troubleshooting

first previous 2 3 4 5 next last

Move Thread

LAN_403

HV Enthusiast

Sun May 11 2008, 11:49AM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Austin wrote ...

I didn't notice this just till now but R10 is open because it said "Not Used" in the parts list however in the schematic it shows a 10k resistor.

I still get nothing out of pin 3 of U4 even after removing R9 and C9 and R10

Then something is hooked up incorrectly and/or you have a wrong part in there.
If you are getting a trigger signal into pin 2, then you should be getting an output signal.
I'd do the following:

1. Disconnect what the output of the 555 is feeding into. To ensure nothing up chain is preventing it from outputting.

2. Check your resistor and capacitor values which are connected to the 555 as well as the Vcc into the 555.

3. Read the 555 tutorial located here to get a better understanding of 555's.

This circuit is about as easy / foolproof as it comes. No reason you shouldn't be getting no output unless you have a bad part / value or something.

Austin

Sun May 11 2008, 06:39PM

Registered Member #1169 Joined: Wed Dec 12 2007, 09:16AM
Location: Portland OR
Posts: 251

Ok daniel I just went through every resistor, Cap, and Diode to make sure everything is properly in place. Other than the error i found earlier in the schematic, everything seems correct. I lifted up Pin 3 on U4 to see if something else was affecting the output. I still get no output out of U4.

I am getting a good trigger signal into pin 2. R9, C10 and R10 have been removed as suggested. Pin 8 is receiving approx 7 volts and Pin 5 is receiving approximately 4 volts. pot 19 is set to its max value as well.

Wirenut

Sun May 11 2008, 08:31PM

Registered Member #141 Joined: Sat Feb 11 2006, 01:14PM
Location: Southern California
Posts: 96

I didn't notice this just till now but R10 is open because it said "Not Used" in the parts list however in the schematic it shows a 10k resistor

I'm confused. Should r10 be a 10k resistor or should it be open? I just finished building my xenosonic, and I'm also having problems. I'm getting audio in, and the leds move in response, but nothing at the output.

HV Enthusiast

Sun May 11 2008, 08:52PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

R10 should be open. All R9 and R10 is form is a voltage divider into pin 5 of the 555.

With R10 open, you get the full voltage into pin 5. With R10 in, you get 1/2 the voltage into pin 5.

You're probably not getting anything in as you probably don't have enough gain as set by R3. This should be cranked up so you have at least 6V at pin 5 of the 555 when a note is being played.

As stated in the instructions, you should have nominally 7V during a nominal note during playback at pin 5 of the 555.

Austin

Mon May 12 2008, 04:44AM

Registered Member #1169 Joined: Wed Dec 12 2007, 09:16AM
Location: Portland OR
Posts: 251

Daniel R56 in the schematic says 100k ohm resistor but the parts list calls for 1.0M ohm resistor. Which one is it?

I have performed all all suggestions you have given me, and still I get no output from Pin 3 of U4. And now someone else is experiencing the same difficulties as me. Would it be possible for you to double check your schematic and post an updated version because there are clearly quite a few discrepancies between the schematic and the parts list. or should I just go completely off the schematic and ignore the parts list.

HV Enthusiast

Mon May 12 2008, 12:04PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Schematic is correct other than R10, which should initially be "open."

Again, the 555 timer is a very simple device and virtually fool proof. If you aren't getting output, than something is fundamentally wrong in your circuit. Here is the list you need to check out:

1. R18, R19, and C18 are not correct. In particular, check (which means MEASURE out of circuit) that R19 is not shorted - as pots do have a habit of shorting out as a failure.

2. Trigger pulse present: Trigger needs to go less than 1/3 Vcc voltage to trigger. MEASURE with oscilloscope.

3. Control voltage at pin 5. Still not enough. Check your input signal. What is the amplitude of that signal? Maybe your computer output isn't putting out enough? Try switching to the headphone jack and try that as well.

4. Just not reading your oscilloscope properly. At 500Hz, the period is 2ms. If you don't have the timescale properly set, especially with analog scope, you may miss a short 50us pulsewidth.

I'm still betting you're not getting the proper control voltage or that R19 is bad.

I've already fielded about 50 of these units for a variety of groups, and all have shown demonstration level success including a local boy scout troop who built 10 units (for 10 DRSSTCs they have).

If its still a problem, just send it back to me and i'll troubleshoot it for you free of charge (minus shipping of course)

Austin

Mon May 12 2008, 12:34PM

Registered Member #1169 Joined: Wed Dec 12 2007, 09:16AM
Location: Portland OR
Posts: 251

ok Daniel thank you for the support, I will give those suggestions a shot please stand by.

quick question tho, what did you mean by R18 and C18 is wrong? and what should the voltage be at pin 5 even with R9 and C9 removed?

HV Enthusiast

Mon May 12 2008, 06:42PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Austin wrote ...

ok Daniel thank you for the support, I will give those suggestions a shot please stand by.

quick question tho, what did you mean by R18 and C18 is wrong? and what should the voltage be at pin 5 even with R9 and C9 removed?

R18+R19 and C18 are the RC values which determine the length of the output pulse. If R19 was shorted, for example, you'd only have R18 and C18 as your timing components leading to an almost zero length pulse.

With R9 and C9 removed, the voltage at pin 5 should be 2/3 Vcc.

As I said before, you should take a look at the following link which describes everything you need to know about a 555 timer.

http://www.uoguelph.ca/~antoon/gadgets/555/555.html

The 555 in your circuit is working as a monostable operation as described in the tutorial. That is for each trigger input, it only puts out a single pulse.

Austin

Wed Jul 09 2008, 05:38PM

Registered Member #1169 Joined: Wed Dec 12 2007, 09:16AM
Location: Portland OR
Posts: 251

Ok Daniel its working however i'm still getting noise/static in the signal. I was running a stereo .mid song which could be part of the problem. However the xenosonic makes my coil oscillate even if there is no audio input to the coil. This makes me believe there is something wrong. Any suggestions?

here is a video to show what im talking about. notice how the coil runs even if there is no audio input to the xenosonic.

Herr Zapp

Fri Jul 11 2008, 06:08AM

Registered Member #480 Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644

Austin -

For all those who have been following your tribulations with this coil, what did you do that finally got it running? Found a wrong component value, a soldering defect, or something else? In your previous update on coil performance (Sunday, May 11) you mentioned that you still were not getting any output from U4. Suddenly on July 9th the coil is working.

What changed?

Regards,
Herr Zapp

first previous 2 3 4 5 next last

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob