Gauss Drive 1N4448 and also 19k resistor in general

[burger-patty-and-bacon]

https://docs.pedalpcb.com/project/GaussDrive.pdf

On the GAUSS DRIVE, is this a TYPO on the DIODE of 1N4448 or is that correct? I am not finding those on tayda or stompboxparts.

Found on eBay the 1N4448

So here is an odd one.. I am almost done, but I cannot find a 19kohm resistor. Stompboxparts and tayda, no go on the 19k resistor. whats up with that?

 

[burger-patty-and-bacon]

wtf with no 19k resistor at stompbox or tayda.. ODD!!

 

[Danbieranowski]

I'm not familiar with this circuit, but if you need to put together a 19k resistor, you could throw a 16k and 3k in series.

 

[Danbieranowski]

And one limited note on the 1n4448. It looks like the 4148 is an option here. Socket and try! https://www.diystompboxes.com/smfforum/index.php?topic=18820.0

 

[burger-patty-and-bacon]

Just find it super super odd that neither places carry a 19k? why is a 19k considered an odd or non normal value?

so just leg any combo of 2 resistors together that add up to 19K and have one funky looking spot on board?

If I choose to put an 18K or a 20K in place of the 19K, what is the sonic difference that happens between the lower 18k and higher 20K value?

 

[burger-patty-and-bacon]

And one limited note on the 1n4448. It looks like the 4148 is an option here. Socket and try! https://www.diystompboxes.com/smfforum/index.php?topic=18820.0

Thanks. I was able to source the 4448 on ebay here

1970-pcs Diode/rectifier Philips 1n4448/at 1n4448 1N4448AT for sale online | eBay

Find many great new & used options and get the best deals for 1970-pcs Diode/rectifier Philips 1n4448/at 1n4448 1N4448AT at the best online prices at eBay! Free shipping for many products!

www.ebay.com

and another part I could not find I also had to source on ebay

10pcs New 2SJ201 2SJ 201 2S J201 TO-92 TO92 Ic Chips Replacement | eBay

Find many great new & used options and get the best deals for 10pcs New 2SJ201 2SJ 201 2S J201 TO-92 TO92 Ic Chips Replacement at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[Betty Wont]

There is a good chance those j201 are fakes and will not work. Pedalpcb sells legit smd ones presoldered.

MMBFJ201 JFET (Pre-Soldered) - PedalPCB.com

JFET

www.pedalpcb.com

An 18k or 20k resistor will likely sub just fine for 19k with no noticeable effect.

 

[BuddytheReow]

An 18k or 20k resistor will likely sub just fine for 19k with no noticeable effect.

Agreed. I would still socket this to be on the safe side

 

[burger-patty-and-bacon]

There is a good chance those j201 are fakes and will not work. Pedalpcb sells legit smd ones presoldered.

Well that is GREAT! So ebay cannot be trusted from china for parts?

 

[Danbieranowski]

Well that is GREAT! So ebay cannot be trusted from china for parts?

I'd avoid ebay wherever possible. Some folks on here will find reputable sellers on there, but it takes looking through reviews etc. If the price or the availability seems to good to be true, it likely is. For through-hole J201s check out GuitarPCB. For pre-soldered SMD on a board you can get those here through PedalPCB. Other parts will be available at StompBoxParts who are my most trusted vendor. Tayda, Digikey, and Mouser are all good legit electronics supply companies as well (not pedal parts specific).

 

[Danbieranowski]

Just find it super super odd that neither places carry a 19k? why is a 19k considered an odd or non normal value?

so just leg any combo of 2 resistors together that add up to 19K and have one funky looking spot on board?

If I choose to put an 18K or a 20K in place of the 19K, what is the sonic difference that happens between the lower 18k and higher 20K value?

Yes you can stick resistors together in combination to add up to a value that you need (resistors in series add up). It's worth noting that resistors have tolerances. Tayda carbon film resistors have a 5% tolerance. 5% of a 20k resistor is a 1k tolerance one way or the other, so you may measure a 20k resistor and get the 19k value you need.

 

[benny_profane]

Just find it super super odd that neither places carry a 19k? why is a 19k considered an odd or non normal value?

19k is a non-standard value. Check out the following pages for more information as to why. Note that you don't see 19.0 listed in any of the decade listings on the site and doesn't even show up in the E192 series.

Standard Resistor Values: E3 E6 E12 E24 E48 E96 » Electronics Notes

Understand the E3, E6, E12, E24, E48 & E96 series of standard resistor values: what they are, tables of values, why they are used, how they were derived, etc.

www.electronics-notes.com

E series of preferred numbers - Wikipedia

en.wikipedia.org

 

[Danbieranowski]

Just find it super super odd that neither places carry a 19k? why is a 19k considered an odd or non normal value?

so just leg any combo of 2 resistors together that add up to 19K and have one funky looking spot on board?

If I choose to put an 18K or a 20K in place of the 19K, what is the sonic difference that happens between the lower 18k and higher 20K value?

And to answer your question, the likelihood of a resistor value not being available is usually due to its rarity in use. There are various reasons for this. It could be that the person(s) who designed the circuit used a trimmer to find what sounded perfect to them, which was 19k, so they used that value specifically. It could have been that at the time 19k was a more common value than it is today. It could have been that their supplier did have 19k regularly available. Etc.

 

[benny_profane]

The block with the 19k resistor is essentially the Tube Screamer tone control in a fixed position. Take a look here for an analysis. I wouldn't be terribly concerned with getting that value exact.

 

[burger-patty-and-bacon]

Thanks for education on the J201.. I see that is a long discontinued dealio and that the only way to do it now is with the SMD. Crap.. wish I knew that before I placed my $50 PCB order here.. thanks for all the help here, guys. never ending process of learning.

 

[Danbieranowski]

Thanks for education on the J201.. I see that is a long discontinued dealio and that the only way to do it now is with the SMD. Crap.. wish I knew that before I placed my $50 PCB order here.. thanks for all the help here, guys. never ending process of learning.

GuitarPCB intermittently has through-hole J201s. Keep an eye on this page: https://guitarpcb.com/product/jfet-j201/

 

[Mcknib]

Sticking SMD J201s on an adaptor board ain't too difficult

Can't be, I've done it

Get yourself some solder paste use a resistor leg or pin or get a tube of paste with the nozzle on it, dab some on the solder pads stick yer transistor on (the solder paste will act a bit like glue but you'll still be able to move it till it's perfectly placed) then hold it in place with tweezers or small screwdriver on top and simply touch it with your iron for 3 seconds and watch it melt

Solder paste is grey so you'll see it turn silver when it melts

Once the first joints done keep holding it in place with said tweezers and do the other 2

Under magnification of course unless you consume a lot of kryptonite and have amazing super hero vision

 

[burger-patty-and-bacon]

I will have to order the

MMBFJ201 JFET (Pre-Soldered) - PedalPCB.com

JFET

www.pedalpcb.com

from here so i can do my build. I did not realize the "history" of the J201. My new rule shall be to source the bom first before ordering the PCB! I have had a very good fortune up until this big 5 PCB motherlode order I just did where I had a hard time finding 4 or 5 of the components needed.

 

[BuddytheReow]

I will have to order the

MMBFJ201 JFET (Pre-Soldered) - PedalPCB.com

JFET

www.pedalpcb.com

from here so i can do my build. I did not realize the "history" of the J201. My new rule shall be to source the bom first before ordering the PCB! I have had a very good fortune up until this big 5 PCB motherlode order I just did where I had a hard time finding 4 or 5 of the components needed.

These are pretty good. They're a little annoying to solder some old leads into the DSG holes.

 

[Betty Wont]

These are pretty good. They're a little annoying to solder some old leads into the DSG holes.

40 Pin 2.54mm Right Angle Single Row Pin Header

Tayda Electronics - Get It Fast - Same Day Shipping

www.taydaelectronics.com

Header pins make for easy legs. You can do a whole strip at once and break them off as you need them.