fender blender uh ohs

[Albina Shatzman]

I just put together a circuit from a schematic I found on the web. I had
the schematic checked my an electrical engineer and he said it looked good.
So now that I built it, it doesn't work. What can I do to try and fix it?

 

[John Popelish]

I just put together a circuit from a schematic I found on the web. I had
the schematic checked my an electrical engineer and he said it looked good.
So now that I built it, it doesn't work. What can I do to try and fix it?

First, tell us where on the web we can take a look at this circuit.

 

[Albina Shatzman]

http://fuzzcentral.tripod.com/blender.html

The PCB, layout, and schematic should be on that page. The PCB and layout
are at the top and the schematic is a little further down.

 

[Gerry Schneider]

I just put together a circuit from a schematic I found on the web. I had
the schematic checked my an electrical engineer and he said it looked good.
So now that I built it, it doesn't work. What can I do to try and fix it?

Take it back to the engineer and get your money back.
Oh, it was free advice? Hmm... guess you got value for the money.

 

[Zak]

http://fuzzcentral.tripod.com/blender.html

If it doesn't do a thing at all... not even passing through audio - I'd
check the power first, because this is wied through the jack, and those
may be strange or may not even work as you expect with their plug sense
switches.


Thomas

 

[Charles Schuler]

http://fuzzcentral.tripod.com/blender.html

The PCB, layout, and schematic should be on that page. The PCB and layout
are at the top and the schematic is a little further down.

Looks rather straightforward and should work. Assuming the circuit is
getting power, connect a signal generator to the input and walk through it
stage by stage using an oscilloscope or audio signal tracer (or, get a
technician).

 

[Tim Shoppa]

http://fuzzcentral.tripod.com/blender.html

The PCB, layout, and schematic should be on that page. The PCB and layout
are at the top and the schematic is a little further down.

Assuming "it doesn't work" means that you never get anything out no matter
what you put in:

It'a a bunch of simple single-transistor amplifier stages with some
distortion thrown in for fun. Easy to debug: take a signal injector
at the output, move it back towards the input until the signal
disappears. You'll probably discover it's a bad solder joint or
a transistor put in the wrong way around.

Radio Shack doesn't sell their little signal injectors anymore but a web
search turned up several places selling them for less than $3. If you've
ever used a 555, one of those making a square wave at a kHz or so will do
just as well. If you want to really cheap out, touching an input
junction with you finger and listening for 60Hz hum at the output has
a long tradition...

Tim.

 

[Jim Thompson]

If it doesn't do a thing at all... not even passing through audio - I'd
check the power first, because this is wied through the jack, and those
may be strange or may not even work as you expect with their plug sense
switches.


Thomas

Absolutely. The schematic seems to show a "signal-router" type of
jack which typically won't work for power control.

For a recent G-job I couldn't find an 1/8" jack with N/O contacts, so
I had to do a work-around with a CMOS inverter to do the power
switching.

You may have the same problem. Perhaps use a switch instead of a
jack?

...Jim Thompson

 

[Jim Thompson]

Absolutely. The schematic seems to show a "signal-router" type of
jack which typically won't work for power control.

For a recent G-job I couldn't find an 1/8" jack with N/O contacts, so
I had to do a work-around with a CMOS inverter to do the power
switching.

You may have the same problem. Perhaps use a switch instead of a
jack?

...Jim Thompson

It just occurred to me that the jack depicted may be a stereo jack.
If you use a mono plug with a stereo jack the power switching should
work... just make sure the battery connects to the terminal furthest
from the tip.

...Jim Thompson

 

[Neil]

Nice reply DOUCHEBAG......
I thought this was a forum to help out people........oh I guess you don't
have the qualifications to.

 

[Tony]

http://fuzzcentral.tripod.com/blender.html

When will I ever learn not to click on a link that has tripod.com in it. I HATE
$#%^($*%^$&#@###*@$!@!(*^#)$#)*$(*$*^ ING POPUPS.

Tony

 

[Zak]

When will I ever learn not to click on a link that has tripod.com in it. I HATE
$#%^($*%^$&#@###*@$!@!(*^#)$#)*$(*$*^ ING POPUPS.

If you do not like popups, browse the web with Mozilla. I haven't
noticed popups in a few years. And I feel a kind of flash back when
using IE on someone else's computer.

Edit -> Preferences -> Privacy & Security -> Popup Windows -> Block
unrequested popup windows.

Popups in response to a click still work, and you can 'whitelist' sites
if needed.


Thomas

 

[Jim Thompson]

If you do not like popups, browse the web with Mozilla. I haven't
noticed popups in a few years. And I feel a kind of flash back when
using IE on someone else's computer.

Edit -> Preferences -> Privacy & Security -> Popup Windows -> Block
unrequested popup windows.

Popups in response to a click still work, and you can 'whitelist' sites
if needed.


Thomas

Get STOPzilla for IE.

...Jim Thompson

 

[Rich Webb]

If you do not like popups, browse the web with Mozilla. I haven't
noticed popups in a few years. And I feel a kind of flash back when
using IE on someone else's computer.

Or Opera, for another modern browser with a built-in popup killer.

I guess MS decided that since they control most of the market there is
no need for innovation.

 

[John Popelish]

It just occurred to me that the jack depicted may be a stereo jack.
If you use a mono plug with a stereo jack the power switching should
work... just make sure the battery connects to the terminal furthest
from the tip.

I think this is exactly what the schematic indicates. I have seen
this used on several guitar effects boxes, where pulling the 1/4 inch
phone plug out of the box kills the power, this way. I don't care
much for it, because it puts the supply voltage into whatever is the
signal source at the moment the plug is pushed in.

 

[Jim Thompson]

Nice reply DOUCHEBAG......
I thought this was a forum to help out people........oh I guess you don't
have the qualifications to.

Neil,

One thing you need to get used to around here... bitching/abominable
behavior and ignorance go hand-in-hand.

Sorry!

...Jim Thompson

 

[Albina Shatzman]

Now here's the deal...

I found two crappy joints and redid them (although I'm sure there are plenty
more, if not all of them; I'm new to this stuff). Now, I can plug my guitar
into the input, and plug the output into my amp. I turn the amp all the way
up (2 12inch speakers running at 115 watts) and all I get is this really
weak ass signal that sounds like a clean guitar. Where's my clipping!? And
why's it so damn quiet!?

Thanks for all the quick support so far.

 

[John Popelish]

Now here's the deal...

I found two crappy joints and redid them (although I'm sure there are plenty
more, if not all of them; I'm new to this stuff). Now, I can plug my guitar
into the input, and plug the output into my amp. I turn the amp all the way
up (2 12inch speakers running at 115 watts) and all I get is this really
weak ass signal that sounds like a clean guitar. Where's my clipping!? And
why's it so damn quiet!?

Thanks for all the quick support so far.

I would trouble shoot this way:

First I would measure the voltage across the supply rails of the
circuit, to make sure the battery was good and connected through the
input plug to the rails.

I would connect a .1 uf capacitor to the hot terminal of an extra
jack, and connect the ground end to the ground of the circuit. I
would plug the amp into this jack (with the volume turned down low),
and use the other end of the capacitor as a signal tester.

Set all the controls to mid point. Start at the input plug and verify
that the guitar comes through cleanly, there. Then move to the output
side of the first transistor, then the next, etc., verifying each
stage from input ot output. At each stage the volume should either be
louder or more distorted. When you find a node that has much lower
volume than the previous one, you have just jumped over the problem.
You may be able to find the problem by inspection, at that point.

By the way, I hope you didn't solder this circuit with acid core
solder or use plumbers soldering flux paste. These conduct
electricity and partially short any two nodes the flux bridges.

 

[Albina Shatzman]

For soldering, I just used the stuff that cost 9.90 from the local
electronics supply store. The regular like 40/60 ratio stuff or something?

 

[Albina Shatzman]

I looked at it, it's rosin core.