Build Your Own Clone Message Board

It is currently Tue Jun 18, 2024 10:29 pm

All times are UTC - 6 hours




Post new topic Reply to topic  [ 12 posts ] 
Author Message
PostPosted: Thu May 09, 2024 8:55 am 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
So, first time asking anything here. Not native english/american but swede so please be patient with me. Probably forgetting useful info as well except pictures. I know its valuable but I think you can lead me a bit without for now.

Have put together the Analog Vibrato. Led works, bypass works. I know I should reflow every joint (have done a few obvious bad ones) but my pride forbids me at this moment (I also know that pride may kill you....) however, I made me an audio probe and I have sound at leg 3 on the 3207 chip. I think I just may need a little nudging on to the next step.

The sound disappear when turning bias trimpot in either way, stays in the middle.

Am I right when I believe I should have sound on moore legs than nr. 3 as well? Leg 2and 6 has a high pitched squeel that changes with the delay trimpot.

In this thread viewtopic.php?f=20&t=60019&hilit=Analog+vibrato&start=0 I could see that my voltage is very different but I'm not experienced or smart enough to understand if it is a faulty 3207 or another component that gives wrong voltage to 3207.

Legs....
1 0V
2 3,65-3,71V
3 10-12mV
4 7,16V
5 7,65V
6 3,65-3,69V
7 3,78V
8 3,78V

This with a battery 8,55V

Is it leg nr. 1 on 4558 that is output to the output jack?

Well, that one has about 4,23V on every leg except nr 4 with 0V and nr. 8 with full battery V.

Ok, should I swallow my pride and reflow everything and do you still want pictures or can you by this info tell me were I shall put my probe next since I don't get it myself :oops:
And yes, I will do something else a couple of hours now before frying my brain thinking to much.... Been sitting hours with this today.

By the way, I think you have very good instructions but I would gladly pay a little bit moore for a small explanation of whats happening with the signal when it passes the components, with every schematic as well. I love to read such when I sometimes find it. It is very educational when you professionals explain it in detail instead of me making guesses! :oops:


Top
 Profile  
 
PostPosted: Thu May 09, 2024 1:29 pm 
Offline

Joined: Mon Nov 23, 2020 1:39 pm
Posts: 188
Location: Vermont
Quote:
Am I right when I believe I should have sound on moore legs than nr. 3 as well? Leg 2and 6 has a high pitched squeel that changes with the delay trimpot.


Yes, you should have signal on pins 7 and 8 (which are tied together) of the 3207; and having pins 2 and 6 squealing, changeable with the trimpot (trim2, DELAY) position, is expected. (It's not part of the desired audio path; it's part of the signal that times the shuffling the charges through the bucket brigade device.) So you can start there (pins 7/8) to continue your tracing with the audio probe. If it's a good signal there, try the emitters of Q3 and Q4, and yes the 4558 pin 1 should have the signal as well.

It is sensible that the signal cuts out when you turn the trimpot (trim1, BIAS) to extreme positions.


Top
 Profile  
 
PostPosted: Fri May 10, 2024 8:59 am 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
WMP1 wrote:
Quote:
Am I right when I believe I should have sound on moore legs than nr. 3 as well? Leg 2and 6 has a high pitched squeel that changes with the delay trimpot.


Yes, you should have signal on pins 7 and 8 (which are tied together) of the 3207; and having pins 2 and 6 squealing, changeable with the trimpot (trim2, DELAY) position, is expected. (It's not part of the desired audio path; it's part of the signal that times the shuffling the charges through the bucket brigade device.) So you can start there (pins 7/8) to continue your tracing with the audio probe. If it's a good signal there, try the emitters of Q3 and Q4, and yes the 4558 pin 1 should have the signal as well.

It is sensible that the signal cuts out when you turn the trimpot (trim1, BIAS) to extreme positions.
Thanks! The 3207 has no sound on leg 7or 8. Neither does 4558 on leg 1.

The outer transistor of the two that are between 4558 and 3207 has sound but rather weak. The other one has no sound on the emitter. Gaaahh! How can it be sound on one of the transistors but not on the other one when leg 7 and 8 on 3207 doesn't have any sound at all?!? I wish the instructions had the transistor nr on it as well.

Obviously I need a lot moore practise in reading and understanding schematics.... Someone has a good page to read to learn?

However, wouldn't it come sound from 3207 leg 7,8 since it comes in to nr 3? Is 3207 broken? Or am I thinking upsidedown :roll:


Top
 Profile  
 
PostPosted: Fri May 10, 2024 12:29 pm 
Offline
Site Admin
User avatar

Joined: Sun Jan 22, 2006 1:39 pm
Posts: 6009
Location: Richland, WA
Your bias voltage at pin 3 is not sufficient. Pin 3 is biased from the output voltage of pin 7 of IC1B, so you most likely have a bad solder joint in one of the components that lay between those two points. So please put aside your pride and reflow your solder joints.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com


Top
 Profile  
 
PostPosted: Fri May 10, 2024 1:32 pm 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
byoc wrote:
Your bias voltage at pin 3 is not sufficient. Pin 3 is biased from the output voltage of pin 7 of IC1B, so you most likely have a bad solder joint in one of the components that lay between those two points. So please put aside your pride and reflow your solder joints.
Well....I hear you and I will do. Sometimes you have to bow for reality. 9:20 pm in sweden now so tomorrow it begins. No soldering with https://res.cloudinary.com/anora/image/ ... d-snow.jpg in your body :D
It may be good for steady hands after one but more is to much!

Happy friday and thanks byoc, I'll let you know if it works. I really need this to work. It sounds wonderful. Heard it before ordering. Love the "Hawaii sound" you can get from it.


Top
 Profile  
 
PostPosted: Fri May 10, 2024 6:25 pm 
Offline

Joined: Mon Nov 23, 2020 1:39 pm
Posts: 188
Location: Vermont
Quote:
I wish the instructions had the transistor nr on it as well.


Perhaps the map in this post is what you were looking for?

http://www.byocelectronics.com/board/viewtopic.php?p=499109#p499109

(look in the 4th post in that thread, which as of this writing is the last post of that thread)



Based on this description of transistor locations:

Quote:
The outer transistor of the two that are between 4558 and 3207 has sound but rather weak. The other one has no sound on the emitter.


it seems that you have signal on Q2 ("outer"), which makes sense because that transistor's output is what feeds the 3207 pin3; but no signal on Q4 ("other one"), which is consistent with your other observations.


Top
 Profile  
 
PostPosted: Sat May 11, 2024 2:08 am 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
WMP1 wrote:
Quote:
I wish the instructions had the transistor nr on it as well.


Perhaps the map in this post is what you were looking for?

http://www.byocelectronics.com/board/viewtopic.php?p=499109#p499109

(look in the 4th post in that thread, which as of this writing is the last post of that thread)



Based on this description of transistor locations:

Quote:
The outer transistor of the two that are between 4558 and 3207 has sound but rather weak. The other one has no sound on the emitter.


it seems that you have signal on Q2 ("outer"), which makes sense because that transistor's output is what feeds the 3207 pin3; but no signal on Q4 ("other one"), which is consistent with your other observations.
Thank you!! Now that I see it I knew I saw that picture somewhere! Perfect!

Have reflowed almost every joint between leg 3 on 3207 and leg 7 on 4558 but no results yet. Keep trying to understand what I don't understand :roll:

I have put together things like this https://www.velleman.eu/products/view/?id=461832 or this one https://www.velleman.eu/products/view/?id=460644 and smaller just educational builds but they have always been working so I haven't been forced to learn like I do now.

The last week has been challenging for my poor brain but I do thank you for coming to my help!

I also put together the "Bone Bender 2" by Björn Juhl in Sweden. A colleague at work plays in a small band and choosed that one and I soldered it for him a couple of weeks ago. Very fun and sounds really cool with its old germanium transistors.


Top
 Profile  
 
PostPosted: Sat May 11, 2024 5:06 am 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
Ok now, battery 8,43V.... R8 goes from 4,5 V to 2,25V R9 takes it down to 0,005V. Q2 e has 12mV so it works but 3207 needs 4V or more, right?

So leg 7 on 4558 must higher in V. And to get 7 higher then leg 6 has to go higher as well? Is that right? Well, now I'm only speculating. Read the datasheet for 4558 but I still don't get it :cry:

Have reflowed all joints in that area but its time for a cup of strong coffe now.


Top
 Profile  
 
PostPosted: Sun May 12, 2024 5:58 am 
Offline

Joined: Mon Nov 23, 2020 1:39 pm
Posts: 188
Location: Vermont
Quote:
Ok now, battery 8,43V.... R8 goes from 4,5 V to 2,25V R9 takes it down to 0,005V. Q2 e has 12mV so it works but 3207 needs 4V or more, right?


This could be further evidence that, as byoc indicated above, the problem is likely to to lie somewhere between the output of IC1b (its pin 7) and pin 3 of the 3207. (On my Analog Vibrato those points all come in at about 4.47 V, give or take a couple hundredths.)

It's almost as if there are wrong values at C5 or C6 or R10, maybe acting like an unwanted short to ground so that R8 and R9 form a voltage divider between 4.5 V and ground. If you have reflowed all the joints there, perhaps give a close visual inspection to those components and look for problems (for example, confirm the component values, look for short circuits from solder bridges, …).

Here’s another check you could do. Using your audio probe, how do the signals compare (esp. in loudness) at these points:

Pin 7 of IC1b (the 4558);
the R8/R9/C5 junction;
the base of Q2 (Q2b/R9/C6 junction).

I believe those are the three points at which you observed the 4.5 V / 2.25 V / 0.005 V sequence. Those voltages are really just average voltages in the presence of (we hope) varying signals, but you might notice (audibly) the amplitude of the desired signal similarly decreasing.


Top
 Profile  
 
PostPosted: Sun May 12, 2024 9:47 am 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
WMP1 wrote:
byoc wrote:


Jiippiiee! I removed both C5 and C6 and now there is sound all the way out in the jack! Obviously voltage at Q2 emitter and leg 3 on 3207 that rises on leg 7-8 that had zero Volt before removing the capacitors.

But! It also works with them put back again! Weird, it didn't help to reflow the joints but removing them completely and put them back solved the problem!

But what do they do more exact? Is it for cleaning up the signal from distortions? How do I know if they are broken? I don't have a dedicated capacitor tester but C5 has infinite ohm while C6 has 1,3 megaohm. This measured with them of the board, not connected to anything else.

Thanks for all your help! You gotta love electronics! :D at least when you get it to work!


Top
 Profile  
 
PostPosted: Sun May 12, 2024 10:06 am 
Offline

Joined: Mon Nov 23, 2020 1:39 pm
Posts: 188
Location: Vermont
Bjoern wrote:
now there is sound all the way out in the jack!


"Hawaii sound" I hope :)

Bjoern wrote:
But what do they do more exact? Is it for cleaning up the signal from distortions?


Looks like some low-pass filtering. I'm willing to call it "cleaning up from distortions" if you are! Hence it is not surprising that the circuit will nominally work even with the capacitors absent.

I don't think you can learn much about a capacitor from using an ohm-meter on it. Many of us favor getting multimeters that have built-in capacitance-measuring. (I tend to use a dedicated-purpose capacitance meter that, yes, I built from a kit.)

Enjoy your Analog Vibrato, it's quite a nice box.


Top
 Profile  
 
PostPosted: Sun May 12, 2024 1:15 pm 
Offline

Joined: Sun May 05, 2024 3:48 am
Posts: 7
WMP1 wrote:
Bjoern wrote:
now there is sound all the way out in the jack!


"Hawaii sound" I hope :)

Bjoern wrote:
But what do they do more exact? Is it for cleaning up the signal from distortions?


Looks like some low-pass filtering. I'm willing to call it "cleaning up from distortions" if you are! Hence it is not surprising that the circuit will nominally work even with the capacitors absent.

I don't think you can learn much about a capacitor from using an ohm-meter on it. Many of us favor getting multimeters that have built-in capacitance-measuring. (I tend to use a dedicated-purpose capacitance meter that, yes, I built from a kit.)

Enjoy your Analog Vibrato, it's quite a nice box.
Do you want to know something....I can't play any instrument whatsoever :roll:

It just somehow happened a month ago that I bought an electric guitar as a diy kit. And if you have a guitar you also must have a pedal....or 5. Thats the rules! As I wrote earlier in the thread I built another pedal for a colleague at work, that he choosed and payed for but I wanted to try something harder. But that "Bone Bender 2" sounds really great as well. A fuzz pedal.

I was looking for something like dist or fuzz when I saw this and listen to it. I just love the sway and wibe from it. The colleague doesn't know about this one yet but his band meet every thursday so I will ask to come along to trim the Bone Bender but will also have this one with me. It'll be fun to see their faces when they hear it!

And yes, Hawaii, here I come! Gotta learn to play something easy.

By the way, I looked on this page https://www.learningaboutelectronics.co ... -capacitor and there it was said that about measuring the capacitor with an ohm-meter but of course the oscilloscope or a dedicated instrument would be better.

Thanks again for advice!


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 12 posts ] 

All times are UTC - 6 hours


Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group