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sparkey

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Posted: 04:41am 09 Aug 2011

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does any body have a circuit for a flip flop with a clock input ive tried several but cannot sem to get a modified square wave out put ..thanks to all who reply ..sparkey

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rhamer
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Posted: 06:19am 09 Aug 2011

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sparkey said does any body have a circuit for a flip flop with a clock input ive tried several but cannot sem to get a modified square wave out put ..thanks to all who reply ..sparkey

What are you trying to get out? And what is your clock?

I think you are asking for something like a 4013 with the NOT Q output connected to the D input.

Then the Q output will be half the clock frequency.

Regards

Rohan

Rohan Hamer
HAMFIELD Software & Hardware Solutions

Makers of the Maximite Expander.

http://www.hamfield.com.au

sparkey

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Posted: 06:32am 09 Aug 2011

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yes thats what i have built but i only have a single trace cro but by putting the probe accross the two out puts should i see a modified square wave
when i disconnect the positive i get a modified square wave ..wierd,,,but when i probe each output one at a time with the posite connected i get a square wave from each pin ...i have to look for some parts and a transformer and see what happens i guess ...regards sparkeyEdited by sparkey 2011-08-10

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rhamer
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Posted: 07:46am 09 Aug 2011

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sparkey said yes thats what i have built but i only have a single trace cro but by putting the probe accross the two out puts should i see a modified square wave
when i disconnect the positive i get a modified square wave ..wierd,,,but when i probe each output one at a time with the posite connected i get a square wave from each pin ...i have to look for some parts and a transformer and see what happens i guess ...regards sparkey

Sorry, I have no idea what you mean.

How have you got it wired and what signals are on the inputs?

Also what are you calling a modified square wave?

Rohan

Rohan Hamer
HAMFIELD Software & Hardware Solutions

Makers of the Maximite Expander.

http://www.hamfield.com.au

sparkey

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Posted: 08:16am 09 Aug 2011

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i have the maxi pin(7) output to the clk on the 4013
gerards sent me a prog and a sorce code have no trouble with that side of things when i hook the cro up to pin (7) its steady as a rock bueatiful signal better than any tripple 555 timer i have used .....

i have on the 4013
pin 1 q
pin2 q-
pin 3 clk
pin 4 earth
pin 5 to pin2
pin 6 flot and pin7 -tve
pin 14 ptve
the other half is floting on f/f 2

but i am getting a modified sq wave think most of the chips had been zapped but it has a ripple through it ,,could be that even this chip is a little cagged

regards sparkey

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sparkey

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Posted: 08:24am 09 Aug 2011

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basically a sinewave that is square shaped sorry icannot draw one and so sorry ,,,..regards sparkey ...gotto get more chips on thursday

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rhamer
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Posted: 09:47am 09 Aug 2011

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Ground pin 6

If you leave it floating it won't work.

Rohan

Rohan Hamer
HAMFIELD Software & Hardware Solutions

Makers of the Maximite Expander.

http://www.hamfield.com.au

sparkey

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Posted: 10:57am 09 Aug 2011

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done that i think that maybe the top flat line is like peeling off ..could be the chip ..i have it setup on bread board atm did help thogh also how would i amplify the square wave out its ony 3 volts but need it to be higher say 12 volts tried putting the out put to base of bc549 then putting 12 volts on the collector and it really only made it move up the screen didn`t make the wave taller...regards sparkey....oh also juast a short note about the powerd hub nice worh there but u could per haps ad a set of those green screw terminals for easier straight acess to the pins ,,,just a thought .. but i guess then i dont have any four port straight expander boards just the 10 port ..havent had a look at you flyer to see if you do have ...but that hub is a must for any serious jobs ..you make some cool gear,,,sincearly sparkey

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sparkey

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Posted: 12:32pm 09 Aug 2011

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ok so i now have a lm833 running on the outputs its a dual 8 pin op amp and have it powerd by 12 volts doesent seem to have made much difference but the signal is a lot sraight and doesnt seem to be drifting or smearing as far as connts go i have the +in as in the neg in going to the out put straight conn ...i am not shure weather to put a resistor in series here i think it could in crease gain if i am correct ....any constructive critizism welcome ..regards sparkey

technicians do it with least resistance

seco61
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Posted: 01:10pm 09 Aug 2011

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Hi.

What you have described is a unity gain follower.

To provide voltage gain, connect a resistor between out and the inverting input (lets call this resistor R2), and connect another resistor from the inverting input to ground (and call this resistor R1).

The input goes to the non-inverting input as before.

The gain will equal (1 + R2/R1). So for a gain of 3 a value of 2K for R2 and 1K for R1 should work.

Regards

Gerard (vk3cg/vk3grs)

Regards

Gerard (vk3cg/vk3grs)

rhamer
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Posted: 01:15pm 09 Aug 2011

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Go back a step, you should get a nice clean square wave from the 4013 at half the clock freq.

The square wave should swing between 0 and chip vcc

What voltage are you running the 4013 from?

If it's 5v the that will be your maximum.

If it's 12v then that will be your maximum.

However remember the Maximite output only swings 3v and the 4013 with a vcc of 5v needs to see at leas 3.5v to register a logic high.

At 12v it needs about 7v.

So I suspect you are not driving the input within it's range.

Regards

Rohan

Rohan Hamer
HAMFIELD Software & Hardware Solutions

Makers of the Maximite Expander.

http://www.hamfield.com.au

sparkey

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Posted: 01:20pm 09 Aug 2011

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the op amp is running at 12 volts should i fit another op amp on the input side i`ve tried transtors but only to find very dirty jumbled trace on the cro...thanks sparkey

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sparkey

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Posted: 01:49pm 09 Aug 2011

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well gerards trick worked ..i knew i needed resistors but was not shure where.....i have built up a simple transistor transformer 12-0-12 combo with 2 2n3055`s ..and yes if i knew how to do it with fets i would but.. this is what i have ran in the past something works you should not mess with it ....bread and butter...regards sparkeyEdited by sparkey 2011-08-10

technicians do it with least resistance

sparkey

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Posted: 02:10am 11 Aug 2011

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what if i add a op amp between the maxi`s output and the input to the 4013 would this be of any advantage regards sparkey

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seco61
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Posted: 02:20am 11 Aug 2011

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Hi.

As Rohan pointed out, the logic high and low levels of the 4013 are dependant on its supply voltage.

So if you are running the 4013 from 12V, then it would definitely be an advantage (in reality a requirement) to have some form of level translation of the Maximite's 3.3V output to the required level.

An Op-Amp that is also supplied from the same 12V supply as the 4013 with a voltage gain of 3 would do the trick nicely.

regards

Gerard (vk3cg/vk3grs)

Regards

Gerard (vk3cg/vk3grs)

sparkey

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Posted: 02:24am 11 Aug 2011

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ok cool i have all ready done this with a lf 351 but i have a lot of old chips just thrown into draweres so i will build a lm833 to go between the maxi and the 4013...regards ,,am i correct here....thanks

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sparkey

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Posted: 10:48pm 13 Aug 2011

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ok now i am running a 555 timer ito the 4013 but can only get a square wave output not a modifyied waveform i dont know what i`m doing wrong the circuitit self is simplistic do i need to ad some by pas caps ,,i dunno ..

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bigmik

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Joined: 20/06/2011
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Posted: 04:35am 14 Aug 2011

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sparkey said the op amp is running at 12 volts should i fit another op amp on the input side i`ve tried transtors but only to find very dirty jumbled trace on the cro...thanks sparkey

Sparky,

You ARE using x10 or x100 mode on your CRO probe aren't you... maybe you are loading the output, CMOS devices can be very tempermental..

AND Pin 6 should be GND

Transistors could be used to boost voltages for you.

Mik

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

sparkey

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Posted: 06:12am 14 Aug 2011

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what should pin four be /gnd or high thanks...
iv`e bult seceral of these ccts in the -past i must be doing something wrong it beats me ...rrrrrEdited by sparkey 2011-08-15

technicians do it with least resistance

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