The Nixie Clock Works!

[aphex]

Update #2 - Fixed it!!! Needed to pop in the CR2032 battery Works great now!

Update, so swapping out the power supply ended up fixing the problem. Dropped it down to a 9v 1A PS (which is putting out 12.4v) and the voltage is coming out perfect 162v, not blowing fuses anymore.

So after I turn it all on, the digits seem to be refreshing way too slowly (or something else?)

Check out the video of what it does below;

Nixie 1
Nixie 2


----Old Text Below----
Ok, so I finished the build for my Nixie Clock and i'm trying to set the voltage before I mount the tubes.

According to the instructions,

After successful assembly set high voltage using R26 trimmer, measure the voltage across C6 capacitor. Set the voltage to 160V for IN-14 nixie tubes and 170V for IN-18 nixie tubes. Check power supply temperature after 10 minutes of operate, if switching transistor (M1 ? IRF640) and/or inductor are very hot set lower voltage.

So I flip the board upside down, set my Auto Ranging DMM to Vdc, plug in the power and measure across C6 capacitor from the back, it doesn't even show 1V (its down in like 300mV range). It also seems to be nearly the same when the cord is unplugged.

Any ideas what might be wrong? As far as I know, it doesn't have a power switch, the switches on the back are to program the unit. So I assume the power should be hot as soon as its plugged in.

 

[MrDudeMan]

Don't assume it's powered up just because the plug is in then. Start checking the obvious stuff from one end of the schematic to the other. Post the schematic if you have it.

 

[aphex]

The schematic is part of the Build/Owners Manual - http://www.tubehobby.com/datasheets/NCV2.0_manual.pdf

 

[jdobratz]

Make sure the polarity on your power supply is correct. I blew the fuse on mine first thing because the PS polarity was incorrect.

 

[MrDudeMan]

Check the power supply voltages with your meter. Plug it in and check the output of the voltage regulator (U1) which is node VCC5. What is the reading?

Did you assemble the entire thing? As a rule of thumb, it is always a good idea to assemble power components first and make sure everything is within spec before adding additional components.

 

[gorcorps]

Can't help you... but now I want to build one.

 

[mugs]

Isn't there an **OFFICIAL** Help Aphex with his Nixie Clock thread somewhere? There should be.

 

[aphex]

Originally posted by: mugs
Isn't there an **OFFICIAL** Help Aphex with his Nixie Clock thread somewhere? There should be.

I agree! Lol, or just create me my own subforum

 

[Rumpltzer]

Hey, take a pic of what you've got so far. I want to see.

 

[aphex]

Ah yes, well that would certainly be the problem. Fuse is blown. Double checked the voltage on my 12v wallwart and its 16.8v

Doh!

Regulated PS's are 2x as much, so maybe if I get the 9v unregulated adapter I'll be closer to 12v.

 

[EvilYoda]

Originally posted by: aphex
Ah yes, well that would certainly be the problem. Fuse is blown. Double checked the voltage on my 12v wallwart and its 16.8v

Doh!

Regulated PS's are 2x as much, so maybe if I get the 9v unregulated adapter I'll be closer to 12v.

LOL...so in the end you'll have spent the same amount as doing it right the first time. doh

 

[Born2bwire]

I uploaded a video that has some procedures that will troubleshoot most problems with your Nixie Clock.

http://www.youtube.com/watch?v=rHGDaISne2I

 

[So]

Originally posted by: aphex
Ah yes, well that would certainly be the problem. Fuse is blown. Double checked the voltage on my 12v wallwart and its 16.8v

Doh!

Regulated PS's are 2x as much, so maybe if I get the 9v unregulated adapter I'll be closer to 12v.

16.8V isn't too bad. That voltage will dip under load. Assuming this thing is properly designed, there should be a voltage regulator somewhere between the power plug and the main power rail.

What kind of HV power supply are you using to get your 170V? A transformer or a switch mode supply?

<-- sitting here tinkering with the PCB layout for my home designed nixie clock.

 

[aphex]

Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

 

[Born2bwire]

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

 

[aphex]

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

 

[Born2bwire]

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

No, that means that the wallwart is rated to provide up to 1 A, but the current drawn is dependent upon the load. The first thing to do is check the connections using a continuity checker. Make sure you do not have any soldering bridges and that the leads are given a proper connection. The continuity check sometimes gives false shorts when it comes to stuff like diodes since it basically applies a DC voltage (and non-linear devices like diodes or transistors may turn on when given a bias). The next thing to check would be the validity of the parts. Sometimes the fuse doesn't blow fast enough to protect the parts, resulting in a damaged part that may repeatedly blow the fuse despite fixing the original problem (I like to use fast blow fuses myself, but meh).

Usually when you assemble a board you try to do so in stages. Once each stage is completed you test it. So the most logical thing would be to first build the power supply and check the voltages such and so on. A more complex project or thorough manual generally instructs the builder to follow such a procedure.

 

[Demon-Xanth]

Check the voltage across D1 and double check to make sure you got the parts in in the right polarity and the right values in the right spot.

 

[Vegitto]

Look up 'inrush current'.

 

[aphex]

Originally posted by: Demon-Xanth
Check the voltage across D1 and double check to make sure you got the parts in in the right polarity and the right values in the right spot.

I'm actually wondering if I maybe have L1 in backwards. The part I installed seemed to have polarity (one leg was longer), yet the board doesn't mark a positive or negative for L1 (so maybe it doesn't matter?)

I'm gonna go pick up a few more fuses and a 9v - 500ma Power Supply (which will hopefully come in under 12v).

 

[aphex]

Originally posted by: Born2bwire

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

No, that means that the wallwart is rated to provide up to 1 A, but the current drawn is dependent upon the load. The first thing to do is check the connections using a continuity checker. Make sure you do not have any soldering bridges and that the leads are given a proper connection. The continuity check sometimes gives false shorts when it comes to stuff like diodes since it basically applies a DC voltage (and non-linear devices like diodes or transistors may turn on when given a bias). The next thing to check would be the validity of the parts. Sometimes the fuse doesn't blow fast enough to protect the parts, resulting in a damaged part that may repeatedly blow the fuse despite fixing the original problem (I like to use fast blow fuses myself, but meh).

Usually when you assemble a board you try to do so in stages. Once each stage is completed you test it. So the most logical thing would be to first build the power supply and check the voltages such and so on. A more complex project or thorough manual generally instructs the builder to follow such a procedure.

No soldering bridges that I can see. I went ahead and reflowed a few points that looked a bit sketchy, but everything seems to be in ok. No polarity issues I can see (except maybe L1 that I noted in the post above).

The instructions just said to do it in size order, so that's what I did. From here on out though, I'll definately do it in stages. Will def. help during diagnostics.

 

[So]

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

No, that means that the wallwart is rated to provide up to 1 A, but the current drawn is dependent upon the load. The first thing to do is check the connections using a continuity checker. Make sure you do not have any soldering bridges and that the leads are given a proper connection. The continuity check sometimes gives false shorts when it comes to stuff like diodes since it basically applies a DC voltage (and non-linear devices like diodes or transistors may turn on when given a bias). The next thing to check would be the validity of the parts. Sometimes the fuse doesn't blow fast enough to protect the parts, resulting in a damaged part that may repeatedly blow the fuse despite fixing the original problem (I like to use fast blow fuses myself, but meh).

Usually when you assemble a board you try to do so in stages. Once each stage is completed you test it. So the most logical thing would be to first build the power supply and check the voltages such and so on. A more complex project or thorough manual generally instructs the builder to follow such a procedure.

No soldering bridges that I can see. I went ahead and reflowed a few points that looked a bit sketchy, but everything seems to be in ok. No polarity issues I can see (except maybe L1 that I noted in the post above).

The instructions just said to do it in size order, so that's what I did. From here on out though, I'll definately do it in stages. Will def. help during diagnostics.

Sounds like your HV PS is a switch mode unit. Double and triple check the polarity of your transistors. When I built my HVPS from a kit, I got similar symptoms to what you're reporting (virtually 0 output voltage) and the problem was I had put one of my transistors in backwards.

Also, I still think your 12V unregulated wall wart isn't a problem.

 

[Demon-Xanth]

Originally posted by: aphex

Originally posted by: Demon-Xanth
Check the voltage across D1 and double check to make sure you got the parts in in the right polarity and the right values in the right spot.

I'm actually wondering if I maybe have L1 in backwards. The part I installed seemed to have polarity (one leg was longer), yet the board doesn't mark a positive or negative for L1 (so maybe it doesn't matter?)

I'm gonna go pick up a few more fuses and a 9v - 500ma Power Supply (which will hopefully come in under 12v).

Inductors aren't polarized.

 

[aphex]

Originally posted by: So

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

No, that means that the wallwart is rated to provide up to 1 A, but the current drawn is dependent upon the load. The first thing to do is check the connections using a continuity checker. Make sure you do not have any soldering bridges and that the leads are given a proper connection. The continuity check sometimes gives false shorts when it comes to stuff like diodes since it basically applies a DC voltage (and non-linear devices like diodes or transistors may turn on when given a bias). The next thing to check would be the validity of the parts. Sometimes the fuse doesn't blow fast enough to protect the parts, resulting in a damaged part that may repeatedly blow the fuse despite fixing the original problem (I like to use fast blow fuses myself, but meh).

Usually when you assemble a board you try to do so in stages. Once each stage is completed you test it. So the most logical thing would be to first build the power supply and check the voltages such and so on. A more complex project or thorough manual generally instructs the builder to follow such a procedure.

No soldering bridges that I can see. I went ahead and reflowed a few points that looked a bit sketchy, but everything seems to be in ok. No polarity issues I can see (except maybe L1 that I noted in the post above).

The instructions just said to do it in size order, so that's what I did. From here on out though, I'll definately do it in stages. Will def. help during diagnostics.

Sounds like your HV PS is a switch mode unit. Double and triple check the polarity of your transistors. When I built my HVPS from a kit, I got similar symptoms to what you're reporting (virtually 0 output voltage) and the problem was I had put one of my transistors in backwards.

Also, I still think your 12V unregulated wall wart isn't a problem.

They all seem fine to me, all matching the silkscreen layout and all of them match the place they are supposed to be in.

I need to head down there to get some fuses, would swapping for the 9V be fine though?

 

[So]

Originally posted by: aphex

Originally posted by: So

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex

Originally posted by: Born2bwire

Originally posted by: aphex
Can anyone help me understand how the fuse works in this case?

The wallwart was putting out 16.8v, but the fuse is a .8A 250v fuse (I think, the fuse says F800mAL250V). So I assume the 16.8V ramped up to higher than 250V and blew the fuse?

There is a voltage regulator, at R26, but its pretty far away from the power supply & fuse, so I dunno if the fuse blows before it gets to that point.

Usually it's due to current, not voltage. Too much current can be drawn if you have a short or something like that but it is rather difficult to up the voltage unintentionally.

Gotcha. Would the fact that its a 1A wallwart with a .8A fuse be the problem possibly?

No, that means that the wallwart is rated to provide up to 1 A, but the current drawn is dependent upon the load. The first thing to do is check the connections using a continuity checker. Make sure you do not have any soldering bridges and that the leads are given a proper connection. The continuity check sometimes gives false shorts when it comes to stuff like diodes since it basically applies a DC voltage (and non-linear devices like diodes or transistors may turn on when given a bias). The next thing to check would be the validity of the parts. Sometimes the fuse doesn't blow fast enough to protect the parts, resulting in a damaged part that may repeatedly blow the fuse despite fixing the original problem (I like to use fast blow fuses myself, but meh).

Usually when you assemble a board you try to do so in stages. Once each stage is completed you test it. So the most logical thing would be to first build the power supply and check the voltages such and so on. A more complex project or thorough manual generally instructs the builder to follow such a procedure.

No soldering bridges that I can see. I went ahead and reflowed a few points that looked a bit sketchy, but everything seems to be in ok. No polarity issues I can see (except maybe L1 that I noted in the post above).

The instructions just said to do it in size order, so that's what I did. From here on out though, I'll definately do it in stages. Will def. help during diagnostics.

Sounds like your HV PS is a switch mode unit. Double and triple check the polarity of your transistors. When I built my HVPS from a kit, I got similar symptoms to what you're reporting (virtually 0 output voltage) and the problem was I had put one of my transistors in backwards.

Also, I still think your 12V unregulated wall wart isn't a problem.

They all seem fine to me, all matching the silkscreen layout and all of them match the place they are supposed to be in.

I need to head down there to get some fuses, would swapping for the 9V be fine though?

Depends on your clock design. That 9V is going to dip to <9V under load, and that will mean more current draw (assuming you have a voltage regulator) which may make your problem worse, rather than better. I'd triple check for shorts first, as that would be a good explanation for your fuse blowing.