I just finished my Sharkfin 2 days ago and it's ticking(sounds like a click not a thump). The ticking speeds up with the speed control as you might expect in sample hold mode. The ticking can also be heard when bypassed. Another weird thing is that in filter mode the s/h LED flashes about every 12 seconds (no matter whet the speed is set at). It also does this when bypassed.
I have tried changing Q4-6 but that didn't reduce the ticking.
I used a LT1054 instead of the recommended charge pump and it might have quieted it down a bit.
Any ideas as to what would cause this?
did you lift the pin 1 of the LT1054? it mentions that it's required to make it work.
do any of the chips get hot or warm? check for reasonable voltage in the sample and hold portion of the circuit, around Q5-Q6. make sure all the supply pins are correct. check the solder joints, you may have a cold solder (a lead without a proper connection) or short.
Quote from: stecykmi on June 11, 2014, 01:00:14 AM
did you lift the pin 1 of the LT1054? it mentions that it's required to make it work.
do any of the chips get hot or warm? check for reasonable voltage in the sample and hold portion of the circuit, around Q5-Q6. make sure all the supply pins are correct. check the solder joints, you may have a cold solder (a lead without a proper connection) or short.
Lifted pin 1 on the LT1054. I'll check the voltages and solder joints tonight.
Thanks for the quick reply!
I checked the ICs, none are getting hot.
Here are some voltages
Ic1
-
0
.2mv
-8.61
-8
85mv
8.93
-
IC2
-
-.2mv
0
-8.6
-7.99
-.2mv
8.92
-
IC3
-9.13
2mv
0
-9.14
-9.12
255mv
9.44
Increasing mv
IC4
-9.12
0
0
-9.13
-9.12
205mv
9.44
Inc. mv
IC5
-9.13
Flux
-6.72
-9.13
-9.13
-7.06
9.44
Inc. mv
IC6
-
5.34
0
-3.92
0
2.531
1.424
9.44
I was just wondering if using a BS250 with the 1M and 10ohm resistor from the power supply of the sunking II could help with this...
well something is funny because pin5 of the lt1054 should absolutely be around -9v, that's the negative supply pin.
i think the envelope and s/h part of these circuits are fairly independent, meaning this circuit should work without the ic's for the s/h... try pulling ic4 and ic5, as well as q5 and q6 if possible, and see if the envelope portion works okay.
Quote from: stecykmi on June 12, 2014, 11:15:54 PM
well something is funny because pin5 of the lt1054 should absolutely be around -9v, that's the negative supply pin.
i think the envelope and s/h part of these circuits are fairly independent, meaning this circuit should work without the ic's for the s/h... try pulling ic4 and ic5, as well as q5 and q6 if possible, and see if the envelope portion works okay.
Rechecked the voltages because I did them kinda late. Pin 5 is -8.97, my apologies, it doesn't help if I give you bad info.
I did pull the ICs in filter mode and when I pulled IC5 the ticking in filter mode stopped. I replaced it with a different 741 and all is goo with that. I replaced 6 and 3 as well since I bought those together but it still ticks in s/h mode.
Also, reflowed solder joints and checked my grounds, all grounds have continuity. I had read on BYOC that sometimes that can cause ticking.
Tried using the BS250 with the 1M and 10ohm resistors as in the sunking II but that did nothing.
I have also tried a different power supply, no joy.
Could it be a wiring issue? Maybe my enclosure layout is at fault?
so when IC5 was pulled, the circuit worked nicely in envelope mode? when IC5 was replaced, it worked nicely in envelope mode?
when IC3 is pulled, does s/h mode tick? s/h mode works well except for the ticking? with a multimeter, see if you can notice any fluctuation on the power rails that corresponds to the ticking, i'm thinking you might see the voltage dip very briefly after the tick (you might even try probing in AC voltage mode).
obviously, this is the sort of problem that's difficult to troubleshoot, but i'm thinking there is something wrong with the s/h section, possibly something getting shorted during the switching part of the cycle. double check all component values are correct, check the voltages of Q5 & Q6 as well. check for shorts across components using the diode/continuity tester on your multimeter.
Quote from: stecykmi on June 13, 2014, 10:36:48 PM
so when IC5 was pulled, the circuit worked nicely in envelope mode?
(Yes)
when IC5 was replaced, it worked nicely in envelope mode?
(Yes)
when IC3 is pulled, does s/h mode tick?
(Yes)
s/h mode works well except for the ticking?
(Yes)
with a multimeter, see if you can notice any fluctuation on the power rails that corresponds to the ticking, i'm thinking you might see the voltage dip very briefly after the tick (you might even try probing in AC voltage mode).
(I set the speed to the slowest setting but still can't see any fluctuations.)
obviously, this is the sort of problem that's difficult to troubleshoot, but i'm thinking there is something wrong with the s/h section, possibly something getting shorted during the switching part of the cycle. double check all component values are correct, check the voltages of Q5 & Q6 as well. check for shorts across components using the diode/continuity tester on your multimeter.
Yeah this one is a real pain. LFOs seem to be my nemesis.
Q5
14.3mv
Fluctuating
-6.26v
Q6
9.1v
Fluctuating
Fluctuating
I poked around the components but didn't notice any shorts
So I shielded the input jack wire and this cut the ticking down tremendously. So it would seem I just made a poor choice with my wiring layout? When I turn down the guitars volume, the ticking goes away completely. I've tried other guitars and it's the same. I don't know if that means anything.
If you have any buffered pedals, put one in front of the sharkfin. See if that kills the tick.
does it tick while on/engaged but with no guitar plugged in?
Quote from: Morgan on June 15, 2014, 03:08:37 PM
If you have any buffered pedals, put one in front of the sharkfin. See if that kills the tick.
Yeah I think it'll be fine for my use at this point. I always use a tu2 in front so that will probably do the trick. I'll give it a try when I get a sec
Quote from: stecykmi on June 15, 2014, 03:41:37 PM
does it tick while on/engaged but with no guitar plugged in?
Yes it the ticking was noticeable with or w/o the guitar plugged in.
Since shielding the input, I don't really notice the ticking now so much when it's on, maybe because of the filter reducing the highs a bit. But when it's off yes.
does it tick even when the effect is off? maybe check that the jacks/enclosure is properly grounded.
Quote from: stecykmi on June 16, 2014, 03:28:06 AM
does it tick even when the effect is off? maybe check that the jacks/enclosure is properly grounded.
It does tick when it's bypassed. I'll double check the jacks when I get a chance. Thanks again for all your help with this.
matt,
have you been able to solve the ticking issue? Yesterday I've finished my sharkfin build - filter mode seems to be working fine, but in SH mode I get quite loud ticking noise - and it is even worse when the effect is bypassed! When I turn off the SH mode while in bypass the ticking goes away. Ticking corresponds with the LED flasing. Also in SH mode it does that funky kind of sound but not at all as nice as in some demos I've seen. Mine sounds bit muffled, kinda lo-fi..
I'll check the usual stuff - solder joints, etc, but the ticking in bypass is kind of weird..
thanks
Quote from: sumac on August 25, 2014, 10:02:52 AM
matt,
have you been able to solve the ticking issue? Yesterday I've finished my sharkfin build - filter mode seems to be working fine, but in SH mode I get quite loud ticking noise - and it is even worse when the effect is bypassed! When I turn off the SH mode while in bypass the ticking goes away. Ticking corresponds with the LED flasing. Also in SH mode it does that funky kind of sound but not at all as nice as in some demos I've seen. Mine sounds bit muffled, kinda lo-fi..
I'll check the usual stuff - solder joints, etc, but the ticking in bypass is kind of weird..
thanks
I still haven't gotten around to fixing mine completely.
Try moving the filter/sh switch and wires farther away from the input jack and see if the reduces the ticking. If so, then use shielded wire for the input jack and maybe even for the filter/sh switch.
As for the muffled lofi sound, have you messed with the trim pots? There is a wide range of sweep available. Different transistors also affect this. Try a few different 2n5088 in Q4
Thanks Matt
sure I did adjust the trimpots, but I dont seem to be able to get it to sound right. I always end up with T2 fully clockwise and T1 around noon. Will try to swap the Q4 transistor and see what that does.
I did try to move the wires around, I redid the grounding of the whole pedal and.. ticking issue remains.
I thought that if the pedal is true bypass, then it is TRUE bypass :) but this ticking is much more noticable when the pedal is bypassed, but it will go away as you turn down the volume knob on the guitar! Weird stuff
I'm gonna check everything again and post voltage readings.
thanks!
Quote from: sumac on August 27, 2014, 09:30:46 AM
Thanks Matt
sure I did adjust the trimpots, but I dont seem to be able to get it to sound right. I always end up with T2 fully clockwise and T1 around noon. Will try to swap the Q4 transistor and see what that does.
I did try to move the wires around, I redid the grounding of the whole pedal and.. ticking issue remains.
I thought that if the pedal is true bypass, then it is TRUE bypass :) but this ticking is much more noticable when the pedal is bypassed, but it will go away as you turn down the volume knob on the guitar! Weird stuff
I'm gonna check everything again and post voltage readings.
thanks!
No problem. Hopefully that helps
It's also a good idea to post some pics so that people who know more than me can take a look.
Don't know if this is relevant but in a post where ticking (in a different circuit) was an issue, placing a cap across the power pins of the LFO IC fixed it. Ticking comes from power spike drawn by chip. Cap adds additional PS filtering and a bit of power reserve for the chip. Hope this helps.
Is the ticking noticeable when you ae playing also? in the youtube videos and the build docs, it says ticking is just going to be a fact. I didn't think about a buffer in front though.
thank you guys for your replies. I was very busy so the project was put aside for a while, but I will look into it in near future.
well, ticking is noticable while playing, but I can easily live with that... it is not very loud. It is however much worse while in bypass! You always have to bypass AND switch to autowah mode at the same time, otherwise ticking is very noticable.
blearyeyes: thanks for the tip! sorry for my ignorance, but which one would be the LFO IC? I guess something like 100uF will do?
For anyone who might have the same problem..
I've been able to cut down the ticking in bypass down substantially by shielding wires that go to input and output jacks and also shielding the (plastic) jacks with alu foil.. Some slight ticking remains, but it is much better now..
blearyeyes above suggests "placing a cap across the power pins of the LFO IC" anyone has an idea how this would be done? where exactly should I put this cap and what value should I try?
thanks!
I too have ticking when the pedal is bypassed and the switch is in S&H mode.
After poking around a bit tonight, I discovered that a 1uf box cap connected to the pads of the rate LED greatly reduced the ticking while still allowing the LED to blink. I'm using a bright blue LED. I wonder if it's possible the the LED itself is the problem.
It's funny, though, that the ticking isn't really there when the effect is on, only when bypassed.
Does anyone have any thoughts on this?