NEED HELP WITH MY NEOVIBE !!!!!

[Zedmin_fx]

My best guess is that you might have put the whole supply voltage across one of the diodes in the bridge rectifier, which will let the blue smoke out of that diode, so to speak.  I believe this could happen if you connected the ground terminal of the voltage coming in  at pads K/J with the circuit ground.  But, if you removed power immediately, it's possible that you just damaged the bridge rectifier (though I suppose it's possible that the 1000uF filter caps were damaged, as well, but I'd have to think about that).  So if I were you, I would replace the bridge rectifier, make sure I understand how to properly wire up the power supply, and give it another shot.  It's very important that you follow the instructions about not connecting pads K or J to ground, and not letting the power jack make electrical contact with the chassis (and hence, circuit ground).

OK I was wondering if i could make my own bridge recifier? If so what diodes would i need? Also If I have to place another order what eles do you think I should buy? Thanks

[mdh]

You can make your own bridge rectifier, but it would be hard to fit it into the board layout, because the DIP rectifier that the layout uses is pinned out differently from what you would naturally get by wiring up 4 diodes in a bridge rectifier configuration.  By the same token, you should be warned that non-DIP bridge rectifiers of similar size and lead spacing are also pinned out differently from the DIP -- generally the AC inputs are diagonal from each other rather than adjacent.  If you were going to make your own bridge rectifier, you would want to use 1N4001 diodes, but probably the simplest thing is to just reorder the rectifier that you used originally.  While you're at it, it would be a good idea to order a couple more of the 1000uF filter capacitors and another voltage regulator, since they're probably the most likely components to have suffered when you smoked the bridge rectifier.  Plus, transistors are cheap, so pick up a pile of them as well.  If you go this route, please pay attention to isolate the power jack from the enclosure.

There is another option (someone correct me if I'm about to lead the OP astray) that would probably allow you to get by with locally available parts, if you're willing to commit to always using a DC supply with the proper polarity.  You could remove the bridge rectifier, place a single rectifier diode (i.e., 1N4001, 1N4002, etc.) across the upper pair of bridge rectifier pads, cathode (band) toward the square pad (this offers some polarity protection), and a jumper across the lower pair of bridge rectifier pads.  This would mean that pad J would be connected to circuit ground, so that's where you want to attach the negative end of the supply.  Connect positive to pad K, and you should be ready to go (or at least ready to troubleshoot the rest of the circuit).  I'm assuming that the filter caps and voltage regulator survived the incident that smoked the rectifier.

But what I can't emphasize enough is that you need to pay attention to what you're doing here!  No offense, but throughout this whole process you seem to have had difficulty with attention to detail.  First the transistor pinouts were all backwards, then it would seem that you allowed one or the other terminals of the power jack to come into contact with circuit ground (this is still just my theory, but I think it's a good one).  I don't mean to lecture you, but this project *is* considered to be advanced, and one of the reasons for that is that there are a lot of little things that require attention to detail -- 50 resistors to get in the right places, 13 transistors to orient correctly (though R.G. made this easier by orienting them all in the same direction), and the somewhat unusual power supply arrangement.  So please, pay attention!

[krhnyc]

You may want to consider getting some transistor sockets and soldering them your board. These will eliminate two possible issues 1). overheating the part 2) short leads aren't a problem. Additionally, have the option to try different transistors without resoldering.

I use a photographic lupe to examine traces, solders etc. Sharp magnification and it's design allows you to view the board in quadrants.

[Zedmin_fx]

I Guess I will just place an order at smallbear. I Bought a few of the voltage regulators so I dont need thoes. I am goina get 2 recifiers 2 1000mf caps. tell me if there are anyother things ?  I was at radioshack and got some more transistors. And the pinout of thoes other transistors were different than the said they were so it wasent really my fault.

[george]

thanks R.G. ....

[Zedmin_fx]

Well I made my order for smallbear last night but, in the mean time I would like to thank all who have helped me out so far. Even if I blew the friggin thing up after I got it to work . Thank you so very much.

[george]

the lamp driver transistor can be a little bugger too ... I had pinout issues with the darlington that feeds it with the result that one shorted out.  So I replaced that then the lamp driver blew up!  Literally!

As the notes say this is a weak point in univibes and neovibes alike - so use a 2N3904 (higher current rating) and keep a few spares handy ...

Regarding pinouts, it is really worth it to download the datasheet and check what it says the pinout it is before you do anything - advice I wish I followed more often myself because like the salesman I only THINK I know everything ...lol

good luck with it - it's worth it

[R.G.]

Better yet, pick up one of the many to-220 darlingtons available. There are pads on the Neovibe PCB for them to drop right in.

It's all in previous posts.

[Zedmin_fx]

Ok I got my sb order yesterday ( Its missing my leds and one of my diodes was busted) I put in the new rectifyer and votltage regulater and the bulb lights. Its a lot brighter than it used to be But it doesnt blink yet. So do I need to get the voltages again ?? Anything else I should do ?? Thank you so very much for all of your help.

[Zedmin_fx]

Ok I got my sb order yesterday ( Its missing my leds and one of my diodes was busted) I put in the new rectifyer and votltage regulater and the bulb lights. Its a lot brighter than it used to be But it doesnt blink yet. So do I need to get the voltages again ?? Anything else I should do ?? Thank you so very much for all of your help.

[Zedmin_fx]

Know one wants to help me out any more?

[R.G.]

... So do I need to get the voltages again ??

Yes, please.

[Zedmin_fx]

Ok Sir I shall do that as soon as I can get my hands on a meter.  Anything else I should do/look at ? I cannot wait to play with one of these ( my brother did  I did not, however  I got to blow it up )

[Zedmin_fx]

Ok I have a meter tonight so I will be getting the voltages. I will prolly post em to.

[Zedmin_fx]

Ok guys Here are my voltages something is really screwed right? Do you think I cna fix it or not? Thanks



Q1
c-e   2.2
b-e   1.0
b-c   2.4


Q2
c-e   2.6
b-e   .8
b-c   2.7

Q3
c-e   7.9
b-e   1.6
b-c   7.4


Q4
c-e   15.5
b-e   4.4
b-c   15.5

Q5
c-e   8.1
b-e   4.4
b-c   8.4

Q6
c-e   15.5
b-e   4.5
b-c   15.5

Q7
c-e   4.4
b-e   4.5
b-c   8.4

Q8
c-e   15.5
b-e   4.5
b-c   15.5

Q9
c-e   8.1
b-e   4.4
b-c   8.4

Q10
c-e   15.5
b-e   1.7
b-c   15.5

Q11
c-e   23.7
b-e  1.7
b-c   23.7

Q12
c-e   23.8
b-e   5.7
b-c   23.8

Q13
c-e   6.0
b-e   .7
b-c    6.7

[mdh]

Could you post the voltages as described in the "What to do when it doesn't work" thread?  That is, rather than giving us voltages across each pair of transistor pins, give us the voltage on each pin referenced to ground.  Touch the black probe to circuit ground, and keep it there while touching the red probe to each of the test points in turn.