@barry
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UPDATE 1: I tested this on my bench unit and confirmed this to be true. I substituted a genuine 2N5457 with a genuine J201 and while the Tremolo still works the Depth control is not as effective. I am looking into acquiring more suitable through-hole JFETs for this project asap. J201 is not a suitable substitution.
UPDATE 2: I can now confirm that J113 works very well and they are more readily available as through-hole.
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UPDATE 3: One more trick I have had up my sleeve which I have not mentioned in the build document yet but if you look closely at all of the NostalgiTone PCBs that require JFETs you will see there is a place to solder SMD components. While it requires a fine conical point and a bit of skill it will future proof these builds for a long while to come.
see Q5 pads in image below (SMD will lay nicely on the top 3 pads which includes the square pad = Gate)
So for example:
The SMD equivalent of 2N5457 is MMBF5457, J113 is MMBFJ113, etc. Google.
As I recall now, you changed your 2N5457 out for a J201. While I would have thought this would work, and it does, after further investigation, it has a very high minimum channel resistance which won’t shunt the emitter bypass cap effectively. So, while it does work, it is probably the least suitable JFET for the job. I would suggest finding a more suitable JFET such as “Genuine” 2N5457, J113, 2N5486, or MPF102.
Thanks for that Playsforfun.
I will create a section here for them.
I will be also getting proper Tayda drill templates asap guys.
Yes I plan on that soon. It is obviously a good idea.
Its not going to be this week, but soon. I will put out a notice when I do.
GuitarPCB does not sell kits. We do provide support though.
If you have kit purchasing questions you will have to go through whomever you purchased from.
“The one piece I did NOT receive is labeled in the diagram is listed as R18.”
R18 is the current limiting resistor for the status LED (see schematic) which you are using on the 3PDT wiring board since that is where you mounted the status LED, therefore no need for R18 on the main board. So CLR placement is an option, or preference, depending on where you like the status LED (by foot switch, or higher). If you bought this from PedalPartsandKits there should have been a note mentioning that.
“Also C7 and C8 that were sent to me don’t look like resistors, but more like capacitors?”
C7 and C8 are capacitors. (see schematic) and also why the bill of materials and part number is labeled with a “C” and not “R”. Also the capacitor code indicating value is printed on the side.
“The provided picture from your build website has C7 and C8 not looked at all like what I was sent.”
There are many different types of capacitor materials. The ones I see you have are MLCC and are very good capacitors and accomplish the job within the space required. MLCC are perfectly good and I use them all the time.
If you go to our Guides Page (Main Menu Bar) and scroll down there are many helpful guides that will help.
The section I refer to look like this:
I hope that helps.
A big, fat super, congrats!
Now make a separate post and show off that build and tell us all about it.
Note: This is the first circuit I ever sold which has helped keep GuitarPCB afloat for all of these years.
Tonmann approved even, and I cannot believe that it is just a few months shy of 15 years ago.
I probably hand etched, drilled and cut 1,000 pieces of that circuit in the first two years.
As for power filtering it just never came up before, (except Wilkie once, also very recently) but in most cases using good pedal board power supply, or battery, I can assure you I have never experienced noise in the loudest of conditions. That said I can see scenarios where it could be a problem and it is obviously a super easy fix.
The NostalgiTone series will be doing a new revamped version of this great little boost soon enough and power filtering will be one of the many upgrades. I have some new projects just about ready for release first.
If Q3 was a bad FET you should probably replace Q5 with a known good FET as well.
The FET is very important and unfortunately there are a lot of bad FETs out there. Amazon and eBay are highly questionable. When I have them I always batch test first (hoping to get more in a month). You can find them from legitimate sources still, like stompboxparts.com
You may also use J113, J201, MPF102, and all have the same pinout. Make sure it is a reputable source.
Also you will notice what is going on, and where exactly, if you use an audio probe. It saves a ton of troubleshooting when you can hear exactly where to look.
FYI: I will have J201 in stack again, probably tomorrow. Hopefully, J113 as well, in a few weeks.
And one more thing I have just now noticed.
The backs of the showing potentiometers do not have covers.
If the potentiometers that are not showing are the same, (no protection), then you are likely shorting out the circuit against the solder joints.
From the first picture at the top this appears to be the case.
You need some sort of plastic cover.
While an audio probe is the quickest, and best bet, you can also make sure to:
- Re-flow the Tremolo section of the circuit board.
I can’t tell if it is a trick of light but for example this transistor location looks questionable.
Like I said I would re-flow the entire Tremolo section. Also be careful not to stress the ribbon cable solder joints while moving things around.
- Verify that the combination of both transistors and JFETs are in the correct locations. If you subbed any values, double check orientations, etc..
- List voltages you are getting at each pin of the JFETs and transistors and be sure to make it easy to understand which pin, of which Q is receiving a specific voltage.
At this point I suggest an audio probe to easily locate where the problem is.
Whether that be the JFETs, transistors, bad soldering joint, or other items I cannot tell from pictures.
I am not sure what is going on there but I would do a complete reflow and make sure all grounds are good.
