Welcome to Solid State Guitar Amp Forum | DIY Guitar Amplifiers. Please login or sign up.

July 20, 2024, 09:29:51 PM

Login with username, password and session length

Recent Posts


DIY amp directions

Started by Lauren, August 25, 2014, 07:10:38 PM

Previous topic - Next topic


Quote from: Lauren on September 10, 2014, 06:05:37 AM
You. Are. Awesome.

{I know  8)}

After you, there are others; you are the pioneer blazing the trail.

a) It isn't verified, we don't yet know it's error (or misleading) free - you are the gen guin test stunt hampster.

b) What's the exact Radio Shack part number on that board (on the label hopefully "CatNo.")?

c) Is there anything about the drawing that you find confusing, need clarified?

d) As long as the various bits stay connected as indicated you have latitude to move bits around if you have trouble making them fit (the caps mainly, and their lead spacings), just so long as each of the pathways between points stay the same.

e) with this layout you shouldn't have to wait for missing parts 'coz I've tried to make them easy to retro-fit.
If you say theory and practice don't agree you haven't applied enough theory.


Well, looky here...  :)

I just happen to have the same board in my junk that Lauren has...

Radio Shack Cat-No 276-150.
A bit hard to see in the picture but the # is on the copper/solder side of the board.
If it ain't broke I'll fix it until it is.


Okay, after a few quick PM's this is now a dual build thread, both Lauren and galaxiex are going to build identical Ruby amps using the same RS Cat-No 276-150 boards - I feelz a truly Awesomeness thread coming on here now.   :dbtu:

L>No clue what an 8-pin DIL is

Dual In-Line package, the sort your IC is in, two parallel rows of legs.

An 8-pin DIP socket matches your little LM386, even has a notch on the pin one end.  It's  nice touch, but it is not essential

BTW - important point - it should say on that layout that it is the TOP SIDE or component-side view, not the bottom of copper-side view.  Another assumed convention, 'tho you would have worked it out when you looked at the top of the IC.  It has a notch at one end to show the pin-1 end, but they almost always have a little dot or molding mark next to the actual pin-1.

{I have a funny feeling that this was an accident.  In the early days some DIPs had a molding mark next to pin one when the goop had been injected, and not all chips had it, but it was informal, a blemish.  Then some manufacturers started putting deliberate dimples next to pin one and it seems to have become a de facto standard ('tho I know of no literature/datasheet on it).  The official mark has always been the D-shaped checkout in the end, but I've used the dimple since whenever.}
If you say theory and practice don't agree you haven't applied enough theory.


Very awesome! and VERY nice of you Lauren! Thank You! :dbtu:

I'm not sure how far along you are with getting the rest of your parts, so I'll start...

Some housekeeping...  ;)

First off, I'm not going to be following Roly's drawing from post #27 as it doesn't match our circuit boards exactly. (sorry Roly  :))

Edit; It does match, I was looking at it "wrong"  :-[

I will use the Ruby schematic from > http://www.runoffgroove.com/ruby.html to help wire the board.

I printed off the entire page to have a handy reference beside me while I work.

Just a note; in some of the early pics you will see Roly's drawing.
That was before I decided to use the schematic from runoffgroove.

Again apologies,
I am going to break the steps up into many individual posts as I hope it will make more sense that way.
There will be lots of pictures and I don't want to clutter one post with a bunch of steps making it hard to follow.

I work a day job and may not be able to make consecutive posts of the steps, as I'm sure there will be others posting and questions asked in between steps.
And I hope Lauren will be posting pics of her progress too!

Ok, sooo... here we go...  :) (assuming you have all parts at hand...)

The board and schematic.

The socket and the LM386 chip, mine is marked LM386N-1
Which makes it the low voltage version, but still able to handle up to 12V according to the Data sheet.
Not necessary and not shown, I also printed off the Data sheet for the chip. (a good reference to have anyway)

Planning where I will mount the parts, no solder yet.
This looks like a good place for the chip socket.
Notice pin 1 is at the bottom left corner and the socket straddles the 2 center copper strips.
The 2 center strips will be my power and ground connections.

The socket pin numbers as oriented to the picture...



Following the schematic, test placing more parts. no solder.
The schematic does not call the parts by numbers such as R1, R2, etc
so I will refer to the parts by their values and what each part is, eg. *the .100 cap*, or *the 3.9K resistor*.
There are not so many parts, so hopefully this won't be confusing.

I marked the 2 center copper strips with + and - signs on the top component side of the board.
Placed the .100 cap one lead wire at pin 7 and the other lead wire at the 3 hole solder pad just to the left of pin 8.
Placed the 10 ohm resistor leads to pin 5 and to 3 hole solder pad 4 places to the right of the socket.
Placed the 47nF (or .047uF same thing) cap to the RH end of the 10 ohm resistor and to - or "ground" center strip.
Placed the 220uF cap WRONG PLACE will fix in the next pic/post.

Notice how the copper side of the board matches the white (painted ?) ink markings on the top of the board.
Handy for when a few parts need to be connected together.

Ok, that's all for now. Gotta run out and get a 1K pot that I am missing.

Edit; took the day off work today to play and have fun...  :)
If it ain't broke I'll fix it until it is.


So now I am really feeling the pressure to get started!  I know you called yourself a beginner, galaxiex, but you definitely know more than I do just based on what you are already doing and the lingo you use. :)  I am a bit intimidated by this whole thing, but am feeling motivated by your motivation.  I am going to try to put something together now and will post as I go.  I am going to stick with Roly's plans...more of a "Ruby for Dummies," which I am and need in this instance. (And it has my name on it :dbtu:)  I ordered my 1K Pot on Amazon today and should have it by Saturday (gotta love Prime!).  Still need a couple of other pieces, but I appreciate the ability to build around them just to get my feet wet. 

Wish me luck!


Is it necessary for me to mark the board "+/-" the way galaxiex did?  If so, please explain how I should be using the positive and negative sides differently.  How will I know what part of the item goes on which side? Thanks!


Ok.  So I think this would help me a bit to understand the basics.  On the circuit board I have, there are 23 holes going across (held horizontally) and they are "grouped" in twos (vertically) by a gold band.  Then there are 3 individual circles (vertically), followed by 3 circles grouped by a gold band, and a line of circles going horizontally across the board, all grouped by the gold band.  It's repeated on the other side, in the opposite layout.  Roly, your schematics for me has a row of 20 across and goes a-j (10 down).  If I were to label my circuit board, it would 23 across and have 13 holes down, a-m.  How does this affect the build and following your plan, if at all?  What's the difference between the individual circles and the ones grouped by the gold bands? 

Told ya...beeeeggggginnnnnnerrrrrr.  LOL!


I fear I will drive you all crazy soon.  I did not see anywhere in the Ruby plans that I need a socket for the LM386.  Is this something I need to purchase?


No you don't NEED to have a socket to fit the chip and solder it to the board. Many kits and people out there use them to easily swap the part out. Actually many people new to soldering fear touching the iron directly onto the legs of the IC. I think you will get along just fine without one.
"A person who never made a mistake never tried anything new." -Albert Einstein


Thanks, DrGonz78!  Etiquette question:  Should I wait to post a new question until someone addresses the old one?


Quote from: Lauren on September 11, 2014, 06:23:24 PM
Thanks, DrGonz78!  Etiquette question:  Should I wait to post a new question until someone addresses the old one?

Ask all of them that you need help any time. I am leaving the other questions for Galaxlex or Roly to help you. Take your time with the build and even follow layout and picture that Galaxlex provides as you go. Good luck you can do it.  :dbtu:
"A person who never made a mistake never tried anything new." -Albert Einstein


Thanks for your help Dr.  :)


Lauren, trying to answer your ?'s I type it up in word and then copy/paste into a reply like this one...
But don't worry about asking multiple ?'s in multiple posts... we will figure it out.  :)

Here goes... copy/paste from Word...

Hi Lauren, Sorry! I did not mean to pressure or you or have you feel intimidated.
That is the last thing we/I want.
I understand the feeling and just want to reassure you NO ONE here will think you are stupid or get down on you for "dumb" questions.
There are no dumb questions!

(stands on soapbox)  ::)

If we were to compare abilities/knowledge in this area of electronics...

You as a total beginner, are to me, as I am to Roly.
He is light years beyond me in his training, experience, and knowledge of this subject.

So yah, I have "some" experience and hard won self taught knowledge, but for all intents and purposes, I'm a beginner.

The mechanical side of things, the actual "hands on" putting stuff together is "easy" once you have done a few...

Do you play an instrument?
Can you do things like household chores? (Not meant as a gender bias, we all do them)
Mow the lawn?
Cook? Clean? Organize?
Operate a computer?
Mobile device?
Pound a nail?
Hang a picture?

Did you run as a baby? Maybe you crawled first... then walk... then run...

You get the point...

If you can do stuff... you can do this!  :dbtu:
Baby steps. We will help you.

(gets off soapbox)
Sorry, I get carried away sometimes....  ::)

Next... It is "standard" in electronics to have power rails + and – to feed the circuit.
It can't operate without it. The battery power (or wall wart power, etc) has to go somewhere. Battery or other power source all have a plus or minus.
I labelled the rails I chose to use, because all parts of the circuit use power.
And those "rails" run the length of the board.
Marking them is a convenience so I know with a glance which is which.
I will be connecting parts to those rails and I don't want to make a mistake.
They happen, but we try to minimise them by doing everything we can to help ourselves. In this case, mark the rails or whatever you choose to use for power input to the circuit. (I suggest the center rails)  ;)

The difference between the different bands/circles on the board.
Those are places we will solder parts "wires" to. Those wires are sometimes called "leads" Pronounced "leeds".
So a resistor (You have lots!) has 2 leads. Each has to go somewhere. They (the leads) get soldered to a "pad" which you called "bands" and "circles".
Those are "solder pads".
The group of 3 pads will be the most useful as parts have to connect to one-another and having 3 holes all surrounded by a solder pad is very convenient for connecting parts leads to each other.

Whew! I hope that all made sense.   :)

The socket, as the Dr. said.... you don't "need" it. I chose to use one cuz I'm going to buy some different 386 chips that have a higher voltage rating so I can run the circuit from a wall wart of  possibly 12-16 volts.
So the socket is an easy way to change chips if the need ever arises. Sometimes chips "blow up" and need to be changed.
Don't worry about it too much, but if it's not hard for you to obtain a socket, (Radio Shack maybe?) by all means use one.
If not, no big deal.
If it ain't broke I'll fix it until it is.


Hey galaxiex,

Thanks for the post.  The challenge with communicating through writing is that the tone and inflection get lost...I'll be sure to use more of the emoticons in the future.  :o  I was being playful with the comment about feeling pressured, though I am intimated to get this thing going. (Not because of you guys...my own nerves about the unknown, getting zapped (LOL), and wanting to do well with this, even if it takes many attempts).  I appreciate the supportive words  :) and now promise to stop apologizing for my limited knowledge and just ask questions, so that the posts don't become about building me up and rather about building the amp. 

You all have been awesome at providing me guidance and answering my many questions.  I am psyched to show you what I can do.  :tu:

Now I just need to know if the difference in the number of solder pads on my board and Roly's directions matters.  How do I compensate...do I have to move things over in any way? Thanks!


What a great thread. As the founder of this site, I am so proud of our little online family.

No worries Lauren, if you need some confidence boosting periodically that is fine, we all go through those moments sometimes. You're doing great! I look forward to seeing your finished product.
Life is what you make it.
Still rockin' the Dean Markley K-20X


Quote from: Lauren on September 11, 2014, 07:27:07 PM
Now I just need to know if the difference in the number of solder pads on my board and Roly's directions matters.  How do I compensate...do I have to move things over in any way? Thanks!

I'm going to start quoting relevant bits so things don't get too muddled with answers to questions.  :)
(Seen that happen with other threads, other forums)

So, the total number of pads doesn't matter.
We will only use as many pads as there are circuit connection points.
Everywhere a part (also called "component") connects, we need a solder pad.

It's handy that we have a board that has multiple pad holes for component leads,
... and those multiple pad holes all connected together by a .... solder pad.  :o
In this case we have the "group of 3" pads, next to the group of 2 long horizontal "pads" (although I call then "rails"),
and the group of 2 pads near the long edges of the board.
You will notice where I test fit my socket for the chip (chip, also called an IC for Integrated Circuit, or... component, depending on the context)

(I hope I don't seem like I'm going over the top here with explanations.
Others may chime in and use different terms to describe the "same thing" so you need to be familiar with the terminology.  :) )

So my socket straddles the rails, and it's no accident this board was designed this way.
This makes it easy to make the power connections to the socket and chip, and we have the rails to connect other parts to as well.

So, (I use that word alot...  ;) ) you are free to place components wherever you choose. No compensation needed.
To follow Roly's layout... well... it might be a bit awkward since it doesn't really match this board.
(unless I missed something that is not obvious to me... Roly?)

Edit; it does match. I was wrong/looking at it wrong.  :-[

I know you like   <3) that it's called Lauren's Ruby, but since you have this board, I'm going to suggest you follow my layout.  :)

We can call it Lauren's Ruby II  <3)

Edit; No, Lauren is going to build her Ruby based on Roly's layout of Lauren's "Ruby"  :)
If it ain't broke I'll fix it until it is.