Ruby Amp problem

Started by mvotre, September 21, 2014, 05:04:38 PM

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mvotre

hi there. First project, first problems.  :icon_neutral:

Trying to build this one:

http://www.runoffgroove.com/ruby.html

I'm building on a protoboard by the way. Besides a power switch and a led (had those at hand), wich i used at the start of the circuit and works as planned, everything is just as shown in the schematic, except...

I'm trying to send the output to a jack, and then plug it in a cabinet (same thing I do with my Smokey amp, but it got the speaker). So, instead of plugging a speaker, i send the + output to a jack, and ground to ground. Don't work. Checking with my multimeter, I got 4 volts BEFORE the last capacitor, and after it, zero. Any ideas on where I should start checking, or how can I try to find the problem with my multimeter? What I did:

- checked the pins for MPF102 - seens correct.
- checked the polaritys for the capacitor - seens correct also.

So, did I need another wiring for a speaker output, or I'm missing something? Tomorrow I will go to the component store (damn seller sold me a 220v iron, and I just found at home - stupid me), and I can buy the same speaker from my smokey. Should it be worth a try?

I build the schematic TWO times. First didn't worked, then tried to start soldering on a board (stupid move, but whatever). My iron seens to be dirt or something like that, and so my solder doesn't stick. It just flows in the iron. I will buy some flux also, and try to work on that problem too. Then rebuild everything on the protoboard. Same result...

Anyway, it's all fun, in a masochist kind, I guess  :D

tonyharker

I assume you mean DC volts?
If so what you get is correct.  The last capacitor isolates the DC.
That's so you can connect the other side of the speaker to earth/common/ground.

mvotre

sorry, DC volts, yeah..

hmmm, so if i got a current to the last piece, the circuit should work? Maybe my cabinet is the one to blame? I know the cabinet works, but maybe in this setup i got something not quite right. Couldn't find how the Smokey amp got the speaker output...

will buy the speaker tomorrow (I can alway leave that one wired to test some things). Maybe later I will build a test probe (from the Wampler guy books), and try to find where I failed.

mvotre

#3
Update! Got sound!!!

opened my Smokey, and wired extra cables to the speaker. Then removed the pots, and tried to find some problem with my multimeter.

Then I touched the pins on the Jfet and I got sound. Strange, but it only works if i wire it other way. Input where it looks it should be pin 2 on the MF102 I grounded (with the resistor), and on pin 3 the input.

Worked fine, and then I put all the rest (gain and volume tone). Really nice. So tomorrow I will just buy a nice enclosure. :)

mvotre

can I change the title? Now would be something like "Noobie first circuit!"  :icon_lol:

struggling with the solder on my board. The damn thing would'nt stick to the board, and just flow away. Bought some flux, and it helped a bit, but after some effort. Then I remembered some tutorials I saw, and got some steel wool, and cleaned a part of the board. Tadaaaa, the damn thing is super shiny, and the solder sticks like glue.  :icon_redface:

nothing to add at the moment from my building, but I'm sharing the stupid move for some laughs. Now, is there anyway I can really clean the board to start it all again, or it´s better to just buy another? the desoldering wire don't seen to work that nice (used a solder pump, or whatever it is called a long time ago, and i liked that more, but for completely cleaning of the board, I think nothing would do).

So, that's it noobs. Proper plan before you plug the iron in the outlet. I was arrogant because of the sucess with the protoboard, but from now on, I will be humble

duck_arse

what sort of board are you trying to clean, and wot you trying to clean off it? methylated spirits will remove all the flux crap. if it's solder, you can use the "heat and then bang" method, where you molten the solder and then bang the board on the table or a block of wood or something, and the solder (still molten) flies off in all directions. this method is frowned upon, but quick and effective. you can also trail your de-solder braid across the results, and pick up the left over.

you always need to be careful with the sucker, as they will often find the pads and tracks with the bad glue, and quickly remove them from your board. cursing ensues.

if it's a bit of vero, chuck it.
don't make me draw another line.