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Serge VCS trigger in problem
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Ali M



Joined: Sep 01, 2009
Posts: 96
Location: uk

PostPosted: Tue Dec 11, 2012 7:05 am    Post subject: Serge VCS trigger in problem Reply with quote  Mark this post and the followings unread

I have just built the serge vcs onto stripboard and for some reason the trigger input doesn't work.

I can trace the trigger in right to pin 13 of the LM3900, then pin 9 is high regardless of a trigger signal. I have tried swapping the IC, no joy there. From what I can tell the diodes seem to make the pulse at pin 13 very small, about 40mV. But according to Tim Stinchcombe's page the outputs should be low until a trigger signal.

Has anyone got any ideas on this? The signal input works fine, from what I can tell. As do the pots and CV inputs. I'm having a hard job understanding everything surrounding the LM3900. Even through reading Tim's page...

I just really want to get this module nailed as it does so much, especially when it behaves like an oscillator!

Thanks in advance
Ali
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Tim Stinchcombe



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PostPosted: Mon Dec 17, 2012 5:16 am    Post subject: Re: Serge VCS trigger in problem Reply with quote  Mark this post and the followings unread

I just happened to chance upon this thread whilst searching for something else VCS-related. So lots of questions:
Ali M wrote:
I have just built the serge vcs onto stripboard and for some reason the trigger input doesn't work.

I can trace the trigger in right to pin 13 of the LM3900, then pin 9 is high regardless of a trigger signal.
So pin 9 is high in the steady-state, i.e. nothing applied to module - what is pin 10 doing? What is the output (TL072 pin 1) doing? Does the setting of the trimpot have any affect on what happens? (Do you have a scope, or are you limited to a DVM?)
Quote:
I'm having a hard job understanding everything surrounding the LM3900.
Don't we all! They are pretty hard to get ones head round normally - in Serge circuits, doubly so!

Tim

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Ali M



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PostPosted: Mon Dec 17, 2012 12:43 pm    Post subject: Reply with quote  Mark this post and the followings unread

Hi Tim, thanks for the reply! (wicked website btw)

My VCS is at work atm, where I have a scope and a dual bench PSU. So I will have to test pin 10 tomorrow.

The trimpot doesn't seem to be doing anything. I oddly got it to oscillate for a while but then it died away to never return again.

I will check it out tomorrow then report back Smile

Ali
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Ali M



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PostPosted: Tue Dec 18, 2012 9:16 am    Post subject: Reply with quote  Mark this post and the followings unread

With no input or trigger signal applied..

LM3900;
Pin 9 = +14.11v
Pin 10 = +0.11v

TL072;
Pin 1 = -0.12v

If I check 072 pin 1 with a scope I get nothing unless a signal is present on the Input.
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Tim Stinchcombe



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PostPosted: Wed Dec 19, 2012 3:15 pm    Post subject: Reply with quote  Mark this post and the followings unread

Well other than the fact that that is not what you want, those readings don't look anything untoward! Having now re-familiarised myself a bit more with the circuit (there's a thread at Muff's on a not unrelated DUSG problem!), it looks as though your problem could be in many places, so you are just ('just'!) going to have work through it methodically to try and spot what 'doesn't fit'. As a first-off, I would suggest trying to force the trigger circuit into the correct steady, untriggered state - centre the trimpot, and momentarily touch the trimpot wiper to the +12V rail, which should force pin 10 to go high, and 9 to go low. You can then check out some of the other signals to see if they make sense, and also if it stays in the steady-state, see if it will respond to a trigger properly.

You should also check out the 'end out' signal - in the steady state this is normally high - when it goes low, about half way through attack, it will prevent any trigger getting through (the diode connected to it will clamp the other diode on pin 13 so that no trigger can get through to pin 13!)

Tim

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Ali M



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PostPosted: Tue Jan 08, 2013 6:02 am    Post subject: Reply with quote  Mark this post and the followings unread

Ok, I think I have been through it pretty methodically. I'm fairly sure there is something I am missing though.

I tried forcing the trigger circuit as mentioned. It appeared to have little effect. The pins don't appear to change state.

One thing I did notice was that applying a CV, I was using a LFO, to rise/fall/both inputs makes the 'end out' output a pulse. But with no CV no pulse....


When faultfinding the circuit, I pretty much did things in this order;

Checked supply voltage on the rails and then the IC's.
Checked for shorts across stripboard tracks.
Checked for bad solder joints.


Then I started to check through the trigger circuit with my scope by;
Appling a square wave to the trigger input
Tracing the signal with my oscilloscope to the LM3900 starting from the first resistor, then through the capacitor.
Square changes shape to a very small spike (Maybe 20mV - I haven't got the circuit in front of me) after two of the diodes going into pin 13.


I initially thought that the signal is too small to be any use to the LM3900, but then remembered that it operates current. Which then got me scratching my head wonderin g how to test it without having to remove the chip and make a bodged breadboard sub board.
But then I'm not 100% what I am actually looking for with regard to current opertations and it would be a lot of work.

I did check the diodes, just incase one was dead from overheating or anything..
I also checked the orientation of all the trannies on my multimeter and everything seemed to be correct.
I swapped all the IC's and got exactly the same results...

Stumped for a while Confused
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Tim Stinchcombe



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PostPosted: Thu Jan 10, 2013 3:26 pm    Post subject: Reply with quote  Mark this post and the followings unread

Ali M wrote:
I tried forcing the trigger circuit as mentioned. It appeared to have little effect. The pins don't appear to change state.
Then I think this means either a build error in this flip-flop part of the circuit, or that the '72 pin 1 small negative voltage you reported above is holding the flip-flip in the 'set' state.

For the former, carefully check your build, especially that the 220k coming off pin 9 is off pin 9 and not pin 11, which I think most definitely would hold the flip-flip in the set state (of pin 9 high, 10 low). Measure the voltage at the 220k/68k/base - for pin 9 high it should be at the rail; if 9 is low, or the 220k is going to the wrong place, it will be about a diode drop below the rail (and the PNP will be on).

If the error is not there (most likely I feel), then I suggest lifting one end of the 100R at '72 pin 1, to isolate it from the flip-flip - then we can concentrate on checking if the flip-flop works. If lifting the 100R changes the state of pins 9 and 10, to the correct non-active one of pin 9 lo and pin 10 hi, then we are on to something. You should also be able to get the flip-flop to change state: when 9 hi and 10 lo, touching the trimpot wiper to rail should now change the state to 9 lo, 10 hi, and releasing the wiper from the rail shouldn't make it change back; to do that, you will need to apply a trigger input (pin 13).

If you can get the flip-flop to work, then still with the 100R lifted, take a look at the comparator output, TL072 pin 7: with pin 9 hi the PNP should be off (measure volts at its base...), pin 5 should be halfway between the envelope out (pin 1) and -12V and climbing (as should pin 1 be), and pin 7 should be at the negative rail. If pin 1 makes it to the positive rail, you may have to try resetting the flip-flip by touching the trimpot wiper to rail again, and otherwise juggle rise/fall settings to try and get your head round things....!

When pin 9 is low, the PNP is on, the diode on its collector goes reverse-biased allowing pin 5 to follow pin 1, and pin 7 should be saturated at the positive rail, and the envelope falling.

That is probably enough to overload you with now, suffice it to say that if/when you find something that doesn't fit any of this, then that is when you can start (trying) to home-in on the error (fingers crossed!).

Quote:
One thing I did notice was that applying a CV, I was using a LFO, to rise/fall/both inputs makes the 'end out' output a pulse. But with no CV no pulse....
Well at least that shows that some parts of the circuit are doing something, and so this is useful information - you should try and determine if the pulse is appearing at the correct part of the LFO cycle, so as to check that something isn't 'backwards'!

Quote:
But then I'm not 100% what I am actually looking for with regard to current opertations...
Current or otherwise, bridging the hole in your understanding is really the necessary part involved to find the bug!

Tim

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Ali M



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PostPosted: Wed Feb 06, 2013 4:23 am    Post subject: Reply with quote  Mark this post and the followings unread

Sorry Tim, didn't get a notification for this.

Thanks for the reply, I am about to get this back on the bench!
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Ali M



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PostPosted: Thu Feb 07, 2013 9:11 am    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
For the former, carefully check your build, especially that the 220k coming off pin 9 is off pin 9 and not pin 11, which I think most definitely would hold the flip-flip in the set state (of pin 9 high, 10 low). Measure the voltage at the 220k/68k/base - for pin 9 high it should be at the rail; if 9 is low, or the 220k is going to the wrong place, it will be about a diode drop below the rail (and the PNP will be on).


220k is in the correct place. The transistor base is 14.68v with pin 9 in a high state.

Quote:
If the error is not there (most likely I feel), then I suggest lifting one end of the 100R at '72 pin 1, to isolate it from the flip-flip - then we can concentrate on checking if the flip-flop works. If lifting the 100R changes the state of pins 9 and 10, to the correct non-active one of pin 9 lo and pin 10 hi, then we are on to something. You should also be able to get the flip-flop to change state: when 9 hi and 10 lo, touching the trimpot wiper to rail should now change the state to 9 lo, 10 hi, and releasing the wiper from the rail shouldn't make it change back; to do that, you will need to apply a trigger input (pin 13).


Ok, I did it in a rush and can't remember the old states of pin 9 and 10. But now I have lifted the 100R. Pin 9 now goes into a low state when I touch the wiper to +rail and it stays like that until I introduce a trig in.
Pin 10 also goes high respectively.
Now we are getting somewhere!

Quote:
If you can get the flip-flop to work, then still with the 100R lifted, take a look at the comparator output, TL072 pin 7: with pin 9 hi the PNP should be off (measure volts at its base...), pin 5 should be halfway between the envelope out (pin 1) and -12V and climbing (as should pin 1 be), and pin 7 should be at the negative rail. If pin 1 makes it to the positive rail, you may have to try resetting the flip-flip by touching the trimpot wiper to rail again, and otherwise juggle rise/fall settings to try and get your head round things....!


Although the PNP in an off state only drops from 14.68v to 14.30v at the base. Not sure if this is enough. In an off state it seems to match the voltage drop of a diode.
Pin 5 is half way, and Pin 1 rises to around 0v from -14v. 072 Pin 7 is 14v when pin 9 is low. when high its around 0v.
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Tim Stinchcombe



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PostPosted: Thu Feb 07, 2013 1:34 pm    Post subject: Reply with quote  Mark this post and the followings unread

After my last post I spotted that on my schematic I have written that the 22k coming off TL072 pin 7 is actually a 220k in my module (and printed in the silkscreen) - I can't see this causing your problem, only that your envelopes may run faster than normal with a 22k instead. So...

Ali M wrote:
220k is in the correct place.
Good.
Quote:
The transistor base is 14.68v with pin 9 in a high state.
That sounds OK - my 'at the rail' neglected the fact that pin 9, when high, will not quite reach the rail, so...
Quote:
Although the PNP in an off state only drops from 14.68v to 14.30v at the base. Not sure if this is enough. In an off state it seems to match the voltage drop of a diode.
...when you take the potential divider effect of the 68k + 220k into account, the 14.68V for off, and 14.3V for on sounds fine.
Quote:
Ok, I did it in a rush and can't remember the old states of pin 9 and 10. But now I have lifted the 100R. Pin 9 now goes into a low state when I touch the wiper to +rail and it stays like that until I introduce a trig in.
Pin 10 also goes high respectively.
Now we are getting somewhere!
So it looks like the flip-flop is probably wired OK.

Quote:
Pin 5 is half way, and Pin 1 rises to around 0v from -14v. 072 Pin 7 is 14v when pin 9 is low. when high its around 0v.
Some of that doesn't sound correct, particularly the "Pin 1 rises to around 0v from -14v": pin 1 shouldn't go negative for an envelope (and with nothing input at 'IN'), but you will need to be a bit more precise about what pins are in what state with respect to other pins, and when. Check this pic:
Posted Image, might have been reduced in size. Click Image to view fullscreen.
and the description which goes with it - the mauve is pin 7, and you'll need to check carefully that it has the right value for the different phases of the envelope, and with what pin 9 of the '3900 does:
- pin 9 hi = attack; pin 7 saturated at neg rail; pin 5 negative and 'tracking' pin 1 (pin 5 has a negative offset with respect to pin 1), from about -6V up
- pin 9 lo, not attack; pin 7 saturated at pos rail; pin 5 following pin 1
and I suggest you keep the 100R disconnected, so you'll have to flip pin 9 manually, as already mentioned, and you may manage to see the third state of pin 7:
- pin 9 lo, 'inactive'; pin 7 hovering around ground, and pin 1 at ground

Hopefully some of this won't be right, which will indicate something is perhaps amiss with all the transistors feeding pin 2...

And also hopefully your scope is dual trace and you'll have to experiment with getting some sort of repeatable triggering event on one channel, to which you can refer everything to whilst repeatedly probing different points with the other channel (if you get my drift!?).

Tim

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Ali M



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PostPosted: Fri Feb 08, 2013 6:50 am    Post subject: Reply with quote  Mark this post and the followings unread

Yep I'm with ya Tim. Resetting and then triggering is messing with my brain a bit!

Quote:
- pin 9 hi = attack; pin 7 saturated at neg rail; pin 5 negative and 'tracking' pin 1 (pin 5 has a negative offset with respect to pin 1), from about -6V up


It is doing this.

On a trigger in; 9 goes high, p5 briefly goes to -6v then floats at 0v. P7 briefly goes to -13v then floats at 0v.

On a reset (by shorting the wiper)
9 goes low, p5 briefly goes to 6v then floats at 0v. P7 goes to 14v and remains there until another trigger in.

Sorry, what I said before about pin 1 is slightly wrong. It seems to be inverted. So it starts at 0v and at a trigger in goes to -14v.
I was trying to do it all in a rush. My bad
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Tim Stinchcombe



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PostPosted: Sat Feb 09, 2013 7:50 am    Post subject: Reply with quote  Mark this post and the followings unread

Ali M wrote:
On a trigger in; 9 goes high, p5 briefly goes to -6v then floats at 0v. P7 briefly goes to -13v then floats at 0v.

On a reset (by shorting the wiper)
9 goes low, p5 briefly goes to 6v then floats at 0v. P7 goes to 14v and remains there until another trigger in.

Sorry, what I said before about pin 1 is slightly wrong. It seems to be inverted. So it starts at 0v and at a trigger in goes to -14v.
Well sadly none of this sounds like correct behaviour - it is tempting to think simply that pins 5 and 6 of the TL072 are flipped, thus making pin 7 the opposite of what it should be, but thinking your symptoms through, I'm not sure it is. However, have a thorough check in that region for shorts, that connections between components are all where they should be etc.

It is possible that the main integrator has something wrong (TL072 pins 1/2/3), especially perhaps with the transistors at its input, but since pin 7 controls both pairs (for rise & fall), again I'm not convinced that is where the error lies. But it will be worth checking that that section behaves as it should, which will be easily accomplished by lifting the 22k at the pin 7 end - attaching this to either rail or ground, you should be easily able to tell if pin 1 o/p is doing what it should:

- ground the 22k: pin 1 o/p should at or near ground regardless of the rise/fall pot settings
- tied to the negative rail, pin 1 o/p should ramp up, and when it hits close to the pos rail, stay there. Only 'rise' settings should affect the speed of the ramp
- tying the 22k to pos rail, then pin 1 should ramp down, from wherever it started till it saturates near the negative rail. Only 'fall' settings should affect the speed

You may need to juggle touching the 22k between all three to get the ramp into a suitable place to start from.

If none of this is right, you'll need to carefully check that all those transistors' bases, collectors, emitters are in the right place, and NPNs - PNPs right etc. (And whilst you are doing this, if at all possible, find the datasheet for the exact make of transistors you are using, so you can be 100% sure the pin-outs you are using is correct - at this stage of the game, all assumptions need to be checked!)

We must be getting close now, as there isn't much else left to check! If the ramping appears correct, then we'll need a think about an easy way to check comparator 5/6/7.

Tim

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Ali M



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PostPosted: Fri Apr 26, 2013 2:23 am    Post subject: Reply with quote  Mark this post and the followings unread

Sorry for the radio silence Tim. I have had so much on at work I haven't really had a chance to work on the circuit. I haven't actually had a chance to work on any of my own electronics.

Its back on the bench now, I will be testing it over the next week.

Don't give up on me Wink
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Ali M



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PostPosted: Fri Apr 26, 2013 6:28 am    Post subject: Reply with quote  Mark this post and the followings unread

Tim Stinchcombe wrote:
....But it will be worth checking that that section behaves as it should, which will be easily accomplished by lifting the 22k at the pin 7 end - attaching this to either rail or ground, you should be easily able to tell if pin 1 o/p is doing what it should:

- ground the 22k: pin 1 o/p should at or near ground regardless of the rise/fall pot settings
- tied to the negative rail, pin 1 o/p should ramp up, and when it hits close to the pos rail, stay there. Only 'rise' settings should affect the speed of the ramp
- tying the 22k to pos rail, then pin 1 should ramp down, from wherever it started till it saturates near the negative rail. Only 'fall' settings should affect the speed

You may need to juggle touching the 22k between all three to get the ramp into a suitable place to start from.


Ok,
When I power up the circuit the 22k starts at ground.
Connecting to negative, pin 1 instantly rises to near positive rail.
Connecting to positive, pin 1 instantly falls to near negative rail.
Neither of these seem to be effected by rise or fall times as you describe. It's an instant fall or rise.

Connecting to ground doesn't reset it to 0v, the voltage at pin 1 stays the same.
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Tim Stinchcombe



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PostPosted: Sat Apr 27, 2013 6:58 am    Post subject: Reply with quote  Mark this post and the followings unread

Ali M wrote:
When I power up the circuit the 22k starts at ground.
Connecting to negative, pin 1 instantly rises to near positive rail.
Connecting to positive, pin 1 instantly falls to near negative rail.
Neither of these seem to be effected by rise or fall times as you describe. It's an instant fall or rise.

Connecting to ground doesn't reset it to 0v, the voltage at pin 1 stays the same.
Well my initial reaction to that is that you have pins 2 and 3 swapped, and so the op amp is acting as a comparator, rather than an integrator (i.e. it is now working with positive feedback, rather than negative). However, some op amps can do horrid things if the inputs are taken outside their supplies (leading to a condition called 'phase reversal', where the input pins seem to act opposite to what one would normally expect), so double-check its supplies. i.e. that you have -15V at pin 4 and +15V at pin 8.

If all does seem OK, then you could measure the voltage at pin 2, and repeat the above: if it is operating with negative feedback, pin 2 should be very close to ground all the time (probably so close you won't be able to get any sensible reading off it); anything else, more than a few mV, means it is definitely not wired/working properly.

Tim

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Ali M



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PostPosted: Mon Apr 29, 2013 2:39 am    Post subject: Reply with quote  Mark this post and the followings unread

Well the supply voltage is correct and I have looked over pins 2 and 3. Everything appears to be wired up correctly.

I have measured the voltage at pin 2 by connecting the 22k to positive and negative rails. With the 22k connected to;
Nothing = 0v
+15 = 0.750v
-15 = -0.750v

I'm going to try replacing the TL072 to see if its that, although I have my doubts.
(edit - nothing wrong with the TL072)

Ali
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Tim Stinchcombe



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PostPosted: Mon Apr 29, 2013 1:46 pm    Post subject: Reply with quote  Mark this post and the followings unread

Ali M wrote:
Well the supply voltage is correct and I have looked over pins 2 and 3. Everything appears to be wired up correctly.

I have measured the voltage at pin 2 by connecting the 22k to positive and negative rails. With the 22k connected to;
Nothing = 0v
+15 = 0.750v
-15 = -0.750v
Well I shall recant some of what I said before:
Quote:
if it is operating with negative feedback, pin 2 should be very close to ground all the time (probably so close you won't be able to get any sensible reading off it); anything else, more than a few mV, means it is definitely not wired/working properly
particularly the 'all the time' bit - I had overlooked that it is an integrator, and so when the o/p reaches either rail, the op amp is unable to keep the inverting input at virtual ground, and so it may then no longer be ground. Hence your values of +/-750mV look OKish - my simulation makes them about 500mV, but I think that is close enough (within the confines of transistor types/actual pot settings etc.).

So, next thing that comes to mind (we're fast running out of options!), is whether the feedback cap is really the desired value of 22nF - if it were way to small, it would charge quickly and make pin 1 quickly saturate, either pos or neg, with apparently little impact on the pot settings..?

Tim

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Ali M



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PostPosted: Tue Apr 30, 2013 1:09 am    Post subject: Reply with quote  Mark this post and the followings unread

Definitely a 22nF Sad

I think I'm going to have to go back over everything you have said and double check it all. I'm thinking it has to be an obvious problem with my board...
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PostPosted: Tue Apr 30, 2013 3:54 am    Post subject: Reply with quote  Mark this post and the followings unread

Might be worth re-re-re-checking for shorts. I recently had the devil of a job getting a circuit on stripboard to work - eventually found the tiniest whisker of solder shorting two strips, hidden in the shadow of an adjacent solder joint. And I'd been over the board with a jeweller's loupe so many times....

Peter
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Ali M



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PostPosted: Wed May 01, 2013 1:03 am    Post subject: Reply with quote  Mark this post and the followings unread

Ok, I resorted to waggling transistors and now if I connect the 22k to positive rail with rise and fall turned to maximum, Pin 1 will slowly fall from 15v to -15....
Result?
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Ali M



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PostPosted: Tue May 07, 2013 7:53 am    Post subject: Reply with quote  Mark this post and the followings unread

Damn thing doesn't work at all anymore. Wicked
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Ali M



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PostPosted: Thu May 09, 2013 7:36 am    Post subject: Reply with quote  Mark this post and the followings unread

Ok, I have built a new one on breadboard (the bain of my life) but this should make testing through it much easier. My cramped boards were not very much fun to work on, anyways...

It appears to be working exactly as my stripboard. The Input, rise/fall times, and rise/fall modulation... But the Trig In and End out produce no signal.

It seems a bit odd that exactly the same fault persists.

Tim, I will go though every piece of advice you have given in this thread and then report back tomorrow. Hopefully there will be something obvious that we have already covered.

Not giving up!
Ali
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Tim Stinchcombe



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PostPosted: Thu May 09, 2013 12:50 pm    Post subject: Reply with quote  Mark this post and the followings unread

Been finding it hard recently to make time to come and comment here, but I do have a few minutes tonight!

Ali M wrote:
Ok, I have built a new one on breadboard (the bain of my life) but this should make testing through it much easier. My cramped boards were not very much fun to work on, anyways...

It appears to be working exactly as my stripboard. The Input, rise/fall times, and rise/fall modulation... But the Trig In and End out produce no signal.
Following one of your previous posts, and before you posted this, I was going to suggest that since something clearly isn't making sense, then perhaps re-flowing all solder joints might do the trick - I've only run across the dreaded 'dry joint' on a few occasions, but when it has happened, the readings I was getting from the circuits made absolutely no sense at all, so I re-flowed joints around the suspect areas, and lo and behold the circuits sprang into life! But now...
Quote:
It seems a bit odd that exactly the same fault persists.
...that you have the same fault again, it does seem to be something 'systematic' rather than a chance bad-luck short or blown component. So, my mind is now thinking along the lines of:

- are you sure the chips are really what they say they are? (I'm looking at a board right now with silver-painted TL084s in it, and it is quite clear the paint is on top of some other markings on the chip, which in my experience of counterfeit chips looks mighty dodgy (though the chips do seem to be doing sensible op ampy things). It is quite easy to do a basic 'is the chip looking OK' test on LM3900s as there are so many diode drops from the pins down to ground, which can easily be checked (often even in circuit) with a standard diode checker on a DVM
- do your transistors have any sort of weird suffix to them? Can't remember the circumstances, but I was fixing something once that required an 'xxx L' transistor, and not the standard 'xxx' type, and was flabbergasted to discover that the pin-out was actually different, even though the transistors were ostensibly the same thing!

Quote:
Not giving up!
That's the fighting spirit needed to get the darn thing (euphemism!) working!

If you have different types of transistors, try those instead in the breadboard version (observing PNP/NPN of course) - the circuit should probably perform tolerably well with just about anything in there. The same is true (though perhaps to a lesser extent) for the op amps too (the LM3900 will have to be an LM3900 though, unless you have some old MC3401s floating around!).

Tim

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Ali M



Joined: Sep 01, 2009
Posts: 96
Location: uk

PostPosted: Fri May 10, 2013 8:16 am    Post subject: Reply with quote  Mark this post and the followings unread

I have tried swapping op-amps and transistors to no effect...

I have used the same IC's (other than the LM3900) in other circuits and never had a problem. The transistors I replaced with BC equivilants today and there was no obvious difference in operation.

Part of me thought there might be an error in the schematic, but I have checked my revision against many others and it all seems to be in order.

Gonna have another play on monday...
Ali
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mattyave73



Joined: May 11, 2013
Posts: 1
Location: Arizona

PostPosted: Sun Dec 29, 2013 6:30 pm    Post subject: Reply with quote  Mark this post and the followings unread

I'm having a similar, but different issue!

Any resolution to OP's issue?
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