Help Replacing BA634 flip flop with CD4013 - BOSS DD2/DD3

[Cozybuilder]

The Japanese data sheet also shows pin 3 is V_EE, which is shown with a limit of -16V, which has to be relative to pin 4; thus (not using ground as a definition) pin 4 is the more positive connection, pin 3 is the more negative.

[ilcaccillo]

Thank you all for your help and explanations.

anotherjim I connected it as per you last suggestions:

Input to Clock
Output to Q
/Q tied to Data
Vdd to High (9V)
Vss, Set1, Clock2, Reset2, Data2, Set2 connected to Low (0V)
Reset connected to Q13 collector

The pedal doesn't turn on at, Output is always zero , doesn't change to 9V when the switch is pressed

With the Set connected to high and reset connected to Q12 collector like you said before, the effect worked with led on, but it was always On, didn't turned off when I pressed the switch

[anotherjim]

I think that those connections are correct.

Does the voltage on the Clock input change when you press the pedal switch? It should be +9V and drop to 0V with the switch pressed. The effect status should change when the switch is released and the clock voltage goes back up. If pressing the switch don't take Clock input near to 0v, guess what the fault actually is?

What voltage is on Reset? It (Q13 collector) should be Low after the reset period. Service sheet says that's 5 seconds after power-on. This also the junction of R60 & R65. Note that if the 4013 Reset pin stays high, it over-rides everything else and won't let Q go high & it won't ever see the pedal switch change .
Yes, if Set input is High the Q output will be over-ridden to high. Set must be Low.
See how in Flip-flops, everything refers to the state of the Q output and the multiple of terms we have for logic levels.
Binary1=Set=On=High=Hi=True=+9V
Binary0=Reset=Clear=Off=Low=Lo=False=0V
So if Set pin is True, then Q is Set. Logical yes?

It is possible for the 4013 to go wrong in this arrangement. CD4000 series chips with a clock/trigger can fail to work properly if the clock input is too slow changing from low to high. To de-bounce the switch, R58 & C48 does cause a slower change. The issue is the clock input circuitry in the chip jitters rapidly causing several triggers when there should be one. You'd need a scope to see it on the Q output -  its too fast for a DMM. There is a way to use the unused half of the 4013 to help solve this if it becomes necessary.

[ilcaccillo]

What voltage is on Reset? It (Q13 collector) should be Low after the reset period. Service sheet says that's 5 seconds after power-on. This also the junction of R60 & R65. Note that if the 4013 Reset pin stays high, it over-rides everything else and won't let Q go high & it won't ever see the pedal switch change .

I'm not at the shop at the moment, I will check the voltage on Reset tomorrow and let you know

Thank you for your help and time,
flip flops are new to me and I'm still learning and trying to understand how they work so your explanations are really helpful

[duck_arse]

In a recent job lot i got a Logic Probe , Would these be used to set / check pin high or low .

a logic probe is like a digital break-out box, it lets you see where your 0's and 1's are/ /are. it does not/ should not "set" the circuit conditions, tho.

(I include the /are joke for Jim.)

[ilcaccillo]

Does the voltage on the Clock input change when you press the pedal switch? It should be +9V and drop to 0V with the switch pressed. The effect status should change when the switch is released and the clock voltage goes back up. If pressing the switch don't take Clock input near to 0v, guess what the fault actually is?

Sorry, had to rectify my measurements.

On clock input I have 4V and bot 9V.
Pressing the switch it changes from 4V to 0V.

If I disconnect the input wire from the 4013 clock, I have 9V there, solder it back the voltage goes to 4V.

"What voltage is on Reset? It (Q13 collector)"

I measure 0V there, no change when switch is pressed.

This is the wiring diagram at the moment:

[PRR]

Not to change tracks on you, but...

The toggle latch in R.G. Keene's relay driver does what you need and is a known-good design.
http://www.diystompboxes.com/smfforum/index.php?topic=116550.0

Note that you must be able to disconnect the pushbutton switch from ground.

You only need the first 3 inverters (ignore the right half of the diagram). The Q12-R59 junction goes to the output of the second inverter. Take the OUT from the output of that inverter; if it comes up in the wrong state, take the output at the third inverter. (Too many inversions for me to work-out clearly.) The unused inverters, ground the inputs and ignore the outputs.

[ilcaccillo]

Hi PRR,
thanks for your input, and you are not changing tracks at all, your suggestions are always welcome.

Actually after your first posts explaining the possible problems in the change of flip flops I decided to just by the BA634 of ebay.
At first when I did this thread "flip flops" were something unknown to me and I thought that changing from BA634 to 4013 was like changing from 2 different Opamps that work the same way but have different pin outs.
I understand after you replys that the change was not that simple.

I only continued trying to use the 4013 because "anotherjim" was so nice and helpfull and I had some 4013 around that why not trying.
So I gave it a go and tried to learn more in the process.
thank you all for that and your patience.

I'm not going anywhere at the moment, I can't seem to make it work.
If I'm not able to make it work with an 4013 I will just buy the dam BA634 of ebay.

Thank you

[PRR]

The CMOS Cookbook has many pages on flip-flops, and I think he expected you to have digested the TTL (or RTL!) cookbook first.

No, it isn't much like opamps. The simplest flop has real problems. The fix is different for different applications. You can make a "universal" flop with a lot of extra pins wired different ways, but that's bad for compactness. (You got just the one; big digital systems go dozens to hundreds and millions of flops.) Then you can define "true" or "not true" as high or low, which is why I'm confused about the reset input and which output you want. So there's like 19 combinations of features and density (flops per chip).

I'd almost be inclined to toss it all out and use a mechanical switch. The alternate action type IS a flip-flop. It does not need power-on "reset" because it will remember its state through power loss. Because many of the clever things you can do with an electronic flip-flop are not too practical in a mechanical flip-flop, you don't get much choice. But I've assumed they had reason to do it in logic; also I have not traced-back those diodes hung on the reset line to see if other stuff needs reset.

[anotherjim]

On clock input I have 4V and bot 9V.
Pressing the switch it changes from 4V to 0V.

Something wrong there. Whatever logic device you use, 4V will not be seen as a valid "1" High level.

If I disconnect the input wire from the 4013 clock, I have 9V there, solder it back the voltage goes to 4V.

Is that 9v on the 4013 clock pin or the wire?
Is it possible your 4013 is damaged? CMOS inputs are very high impedance and should not load the voltage down from 9 to 4v.
If the 4013 clock pin reads 9V with only the meter probe connected to it, the 4013 is probably damaged. If the wire to the clock pin when disconnected shows 9v and falls to 4v when connected, then the 4013  is also probably damaged.

[ilcaccillo]

Is that 9v on the 4013 clock pin or the wire?
Is it possible your 4013 is damaged?

When disconnected I get 9V on the wire that goes from PCB to the 4013.

The 4013 is new, I don't have any reason to think it was damaged before.  And yes tgevreadings were also strange to me, maybe I damaged it, but to be honest I havent done much, I just connected it in the 2 ways we talked in this thread


I can try to use the second unit of the 4013 and connect the first units inputs to low

[anotherjim]

I have seen cases where CMOS pins have about 4v on them and no chip was faulty. This was due to a short circuit between 2 outputs that had opposite levels -  one high and one low. That causes about half of the supply volts to measure on those pins .  If it is this kind of short, then at least 2 other pins will also read about 4volt when the Clock reads 4V. Could be short circuit between any of the Q and /Q outputs (include the unused flip-flop) and the Clock input. If your pcb is stripboard, it's very easy to get shorts due to incomplete or ragged track cuts.

[ilcaccillo]

I have seen cases where CMOS pins have about 4v on them and no chip was faulty. This was due to a short circuit between 2 outputs that had opposite levels -  one high and one low. That causes about half of the supply volts to measure on those pins .  If it is this kind of short, then at least 2 other pins will also read about 4volt when the Clock reads 4V. Could be short circuit between any of the Q and /Q outputs (include the unused flip-flop) and the Clock input. If your pcb is stripboard, it's very easy to get shorts due to incomplete or ragged track cuts.

yesterday before posting here I checked for shorts between pins and had none, everything measured fine in terms of continuity also.
I'm using a pad-per hole perfboard.

[anotherjim]

Consider that it's logic, there is no in-between. 4v is in-between. You should expect less than 1v for a "0" and more than 8v for a "1". Something must be wrong.
Another question, is there +9v on the 4013 pin 14?
By all means try the other flip-flop.

[ilcaccillo]

Hi,
I would like to thank you all for all the help given in this thread.
I ordered some weeks ago a BA634 from Ebay, fortunately it was not that expensive, the location was China.
ordered from this seller:
http://www.ebay.co.uk/itm/1P-x-BA634-CHIPS-ICs-/361101099990?hash=item54134d83d6:g:K7EAAOSwGWNUVfRk

I didnt had time recently to do the next tests on the CD4013 and in the meantime the China BA634 arrived.
The "BA634" that came from Ebay had nothing written on it, and the cosmetics were a bit different than the original unit, at first I suspected it could be a fake.
I installed it in the circuit and Voilá the pedal works again a the circuit switchs on and off perfectly, so the ebay BA634 works well and solved my problem.

Once again I would like to thank you all for your help and support.

I was able to fix 2 DD2/DD3 units recently, and I also have a third DD2 pedal from a friend to compare.
The units I fixed sound good and work properly although the Delay times are different from the third unit. This third unit also seems to sound a bit better, and the delays times seem to be more useful.
I guess I need to calibrate the Clock Frequency now with the Scope on the 2 repaired units. There's 2 trimmers inside the DD2 units for that, one is for the High Freq and another for the Low Freq

[Flaconsius]

Hi. I got some similar problem so do not think convenient to create a new Topic

Got a first generation DD3 to fix. Rewired it and changed D5, D6, D7, and D13.
Also, replaced Q13 and Q11 by a 2SA1015Q12 by a 2SC1815.
And replaced a lot of Caps, majority of Electrolitics of power lines and Switchng system and some others.
Pedal worked ok for a while, but then, it stopped turning on. Only worked in Hold Mode.
ALso, for being sure, replaced R69 and R71.



Power lines voltajes are ok. The "Stranger thing" I´ve noticed was just a few mili Volts in Pin 5 of BA634 (that damn IC). And Measuring Q12 Bas and Collector in Diode Mod, got 0,6V in one Direction and 0,8V with inverted probes.
Just to try, out of ideas, took out Q12 and the Pedal Turned on. And got 8,7V in Pin 5 of the BA634 
When I connected power  cable, it started turned on, and without the 5 second wait. It was fantastic, for a while...
In a couple of minutes Delay sound started to loss Volume and sound really distorted, like a starved OD or Fuzz. It went that way until repetitions didn´t sound anymore. I guess it was working with the reservoir charge of a Capacitor, or... just blew a thing.
May someone help me with an Idea? Thanks in advance.