That is yours in the Picture, I have never used this Marking?
PedalPCB sells 2N5457 by Central, curious if the Marking is the same?
The other one would be Fairchild but I have seen Fakes with them also!
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Clandestine (Chase Tone Secret) noise increases when putting on back lid
- Thread starter harmaes
- Start date
PedalPCB sells 2N5457 by Central, curious if the Marking is the same?
The other one would be Fairchild but I have seen Fakes with them also!
I bought 3 new ones from a trustworthy source in the Netherlands which probably arrive tomorrow.
It might be that the CEN one (which I have a spare one off as well) is not performing correctly?
I will see what happens if I replace it.
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Ok, I had a little fight with the pedal removing the 2n5457 but ended up getting it out and replacing it with a socket.
So I replaced the 2n5457 and the same issue at 9v was still there.
So I tried to connect a 12v out of my Eventide Powerfactor 2 and the noise was gone!
Connecting a 9v from the same power supply introduces the noise again, 12v removes it?
Any explanation on that?
So I replaced the 2n5457 and the same issue at 9v was still there.
So I tried to connect a 12v out of my Eventide Powerfactor 2 and the noise was gone!
Connecting a 9v from the same power supply introduces the noise again, 12v removes it?
Any explanation on that?
What happens if you run it at 9v & adjust the bias so the2N5457 is getting more voltage as it would with 12v???
This circuit is nearly triple the input voltage, 9v is 24 internally.
With 12v, your'e exceeding the Electro's 25v
The voltage I measure using 12v is 27.3v and at the 2n5457 it's 17.0v.
The strange thing is that using 9v the voltage at the 2n5457 is 16.8v. So that's very close already and strange that the pedal behaves so different.
So is the 27.3v or the 17v passed through to the elco caps?
I read this in the Aion Ares documentation:
Charge pump: An LT1054 is recommended for the charge pump, but you can also use a TC1044SCPA. If using a TC1044, jumper the “OSC” pads under the IC socket or you will hear an audible whine. Not sure what he means by audible whine but maybe that can be related to my issue?
Overall it seems like the Ares is better documented IMO.
The strange thing is that using 9v the voltage at the 2n5457 is 16.8v. So that's very close already and strange that the pedal behaves so different.
So is the 27.3v or the 17v passed through to the elco caps?
I read this in the Aion Ares documentation:
Charge pump: An LT1054 is recommended for the charge pump, but you can also use a TC1044SCPA. If using a TC1044, jumper the “OSC” pads under the IC socket or you will hear an audible whine. Not sure what he means by audible whine but maybe that can be related to my issue?
Overall it seems like the Ares is better documented IMO.
Have you tried with a 9V Battery???
Robert has designed this for the TC1044S Or 7660S so Pins 1 & 8 will have a jumper on the PCB.
I would not advise you to try the LT1054!
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I haven't tried with a 9v battery yet. I normally use an external battery to 9v cable but all my 9v batteries are dead so I have to order some.
Which type of batteries do you use for pedals?
In general it's good to know if the pedal works better with a 9v battery but in practice this is still a problem.
Or I can replace the elco caps with higher rated ones.
The issue is the TC1044S & 7660S are on max voltage also @12v.
The LT1054 which I believe is in the Original takes up to 15v so it would be more suitable at 12v power supply.
I would want to confirm with Robert to cut the trace between pins 1 & 8 & also I think C104- 220uF is over the 25v threshold!???
Your in the Nederlands so I don't know if you have clean power or stable power as it should work at 9v.
The 1 Spot 9V is the most reliable power supply I know of for filtering.
I also use the 1 Spot 9v to 18v converter with no issues.
The LT1054 which I believe is in the Original takes up to 15v so it would be more suitable at 12v power supply.
I would want to confirm with Robert to cut the trace between pins 1 & 8 & also I think C104- 220uF is over the 25v threshold!???
Your in the Nederlands so I don't know if you have clean power or stable power as it should work at 9v.
The 1 Spot 9V is the most reliable power supply I know of for filtering.
I also use the 1 Spot 9v to 18v converter with no issues.
Just found this, here is an Original & look at the voltage above the Transistor, maybe it's being starved at lower voltage & that is why your getting a better
result. It is deigned to be at 22v like the Echoplex.
You could try 9v again and crank the trimmer to higher voltage to see if it cures your issue????
Note 35v Electro's!
result. It is deigned to be at 22v like the Echoplex.
You could try 9v again and crank the trimmer to higher voltage to see if it cures your issue????
Note 35v Electro's!
Ok, I took the 9v battery out of my multimeter and tried it. It doesn't make any difference to a 9v PS.
I also increased the bias voltage to above 17v on 9v which didn't make a difference either.
So this isn't related to power I guess? It's concentrated aournd the elco caps and the transistor I guess? Doesn't seem to be the charge pump either.
I also increased the bias voltage to above 17v on 9v which didn't make a difference either.
So this isn't related to power I guess? It's concentrated aournd the elco caps and the transistor I guess? Doesn't seem to be the charge pump either.
Did you use the D105 - 1N4748A in your build?
As you can see inthe Original, no filtering going on in the wiring department!
Did you sawap out the 2N5457?
Yes, I used the zener diode.
I swapped the 2n5457 with the one I had. Receiving some others today hopefully.
Aion uses other transistors. I could try an alternative to the 2n5457 as well. Any other transistors I can try?
I received new ICL7660SCPAZ and 2n5457 today. The 2n5457 were all marked with CEN in front (Central?) and had different gain levels.
I tried all combinations but none resolved the issue with the noise. On 12v it works perfect on 9v it doesn't.
I think replacing 4 of the 5 elco caps to higher ratings is the best way to go for this build and leave it as is.
I tried all combinations but none resolved the issue with the noise. On 12v it works perfect on 9v it doesn't.
I think replacing 4 of the 5 elco caps to higher ratings is the best way to go for this build and leave it as is.
the issue you are having still seems odd, since you get the noise when a metal flat surface is simply held over the PCB even without the lid touching the case. right? any change in the noise when the lid is held over the PCB compared to when the lid makes contact with the case? and compared to when the lid is in place? not sure I have seen anything where the enclosure traps noise inside the case like this seems to do.
It's even stranger that this noise isn't occuring when the pedal is powered with 12v. I can place the lid at the switch side 1/3 and at the top 1/3 and no noise occurs. Only over the elco caps and 2n5457 area does it increase the noise. And even my hand position over it without closing the area produces the same noise. And again not at 12v?!
What I'm curiuos about is if not more Clandestine preamp builders have this but never listened that detailed to it to notice it?
What I'm curiuos about is if not more Clandestine preamp builders have this but never listened that detailed to it to notice it?
It doesn’t, it’s not related to grounding.
With my hand I meant covering it over the open back (without cover). When the cover is on it the hand has no influence. It seems that any material that reflects or bounces back is picked up?
But thanks for thinking with me.
Almost like putting the back on is trapping noise inside the enclosure, which doesn't make any sense.
