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Anyone good at making PCBs?

Started by joecool85, March 25, 2006, 07:03:05 AM

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joecool85

I have a preamp I want to do.  It is the preamp off a Dean Markley K-20X.

Here is the schematic:


I actually just need someone to make the PCB design, I was going to have 5-10 of them printed by a place online.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

trevize

you should learn to use the free pcb-cad program EAGLE and etch your own pcb at home :tu:
it's really a rewarding experience and gives better understanding on what you're working on.

joecool85

Where can I get that?  Is it for PC or Mac?
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

Crystallas

Eagle has been around for a while now, and runs on everything but native solaris and OS/2. Solaris 10 runs it in linux mode just fine, so I dont expect that to change LOL.

http://www.cadsoft.de/

I was going to say for you to use eagle. But its such an obvious answer, I figgured you didnt want to learn eagle to convert it.

trevize

the program is very easy to learn. I wish it had Pspice capabilities for simulation...

Since you are building a new pre i would try to add a fet buffer in front of the ic. It's not
very good to have the guitar signal directly hitting the opamp.

You can fet buffer and boosters everywhere. Look for the "fetzer valve" in the Runoffgroove webpage.
www.runoffgroove.com

Try a fet buffer before your  Dean Markley exisisting amp.

joecool85

I'd have to double check, but from what I remember, the first half of the TL072 is a buffer.

Thanks for the link chris.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

joecool85

Quote from: Crystallas
Eagle has been around for a while now, and runs on everything but native solaris and OS/2. Solaris 10 runs it in linux mode just fine, so I dont expect that to change LOL.

http://www.cadsoft.de/

I was going to say for you to use eagle. But its such an obvious answer, I figgured you didnt want to learn eagle to convert it.

I downloaded it and went to install it, only to find that it only works on OSX 10.3, I'm running 10.4.5 lol.  Luckily my external hard drive is running 10.3.9, so I'll boot that up later and try installing it on there.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

joecool85

Got it working on my external hd.  Wow, I suck at it lol.  I'm sure I can get the hang of it eventually though.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

teemuk

Quote from: joecool85 on March 28, 2006, 07:48:33 AM
I'd have to double check, but from what I remember, the first half of the TL072 is a buffer.

No it's not: TL072 Contains two separate opamps that share the same supply. The first stage of an opamp is always a differential amplifier not a buffer - unless we are talking about a special IC, which TL072 definitely isn't. Note that all TL07x IC's are packed in a standard opamp DIL package: Following this logic, TL071 contains one opamp and TL074 four. The first half is a buffer only if you connect it to be one, see:
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/buffer.html
http://ourworld.compuserve.com/homepages/Bill_Bowden/opamp.htm
http://dolphin.wmin.ac.uk/~alan/components/opamps/
http://www.web-ee.com/primers/files/slod006b.pdf

The input impedance of K-20X seems quite small (220k) for a guitar use. (The common rule of today is that the impedance should be more than 1 Meg). I have never tried K-20X so i don't have experience of it's tone but i seriously doubt the need of separate buffer. The guitar signal can hit opamp directly as well as it can hit a buffer if the input impedance is set correctly and all "safety precautions" are taken into consideration. Placing the buffer before the guitar cord is a different matter. As far as i see it, this preamp should be good as is.

Sorry for being off-topic.

Teemu K

joecool85

I don't know about all that, but it has a really good tone as is in the K-20X.  I don't see why it wouldn't when using it for my preamp.  Right now I have it lined out to my lm3886 and it sounds great.  I like it anyway lol.

Now I just need to make a decent looking PCB design and get it printed.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com