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Hamlet build on perfboard

Started by koky, December 21, 2013, 12:06:52 PM

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koky

 :( Prehistory
After few months I decided to use my SeaUrchin again.  For some reason it is not working. I tried so many times and things didn`t get any better. So I said to myself " Build another one!"
After some reading I ended with Hamlet.

One sub (because here I can`t find them) 1n5817 changed to 1n5819
I`m using TC1044SCPA
http://i608.photobucket.com/albums/tt164/kokySX/21122013242_zps986fe908.jpg
http://i608.photobucket.com/albums/tt164/kokySX/21122013243_zps81a948a3.jpg
http://i608.photobucket.com/albums/tt164/kokySX/21122013241_zpsa91a8cbf.jpg

What is the problem then?
It seams to work somehow because the status LED is working but I don`t have neither bypass or wet (IS that the right term) signal.The only thing is noise, motor-boating and iiiiiiiiiiiiiiiiiiiiiiiiii.... If I turn LEVEL trim CW or CCW it works. If I turn REPEATS pot it is getting faster or slower (that iiiiiiiiiiii is what I mean).
My DC adapter shows 10.80 v  but regardless of that here are some voltage readings:
I. 1044 - I used socket and have cut pins 4 to 7 as it is mentioned in build document
   1. 10.70  5. 2.72
   2. 9.70    6. 9.07
   3. 9.17    7. 8.60
   4. 2.78    8. 10.70
I know that this IC is voltage invertor and some of these values should be negative but this is what I have
II. 78L05  IN - 10.70 GND - 9.19 ???? OUT - 9.44 ???
III. 2399
   1. 9.43   16. 8.11
   2. 0       15. 8.09
   3. 3.07   14. 8.67
   4. 2.44   13. 8.72
   5. 8.72   12. 8.71
   6. 8.78   11. 8.72
   7. 8.78   10. 8.71
   8. 8.71     9. 8.68
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

There's something wrong with your regulator ... actually a couple things.

First, the center pin does not appear to be connected to ground. Fix that first and see if it results in 5V output.

Actually, there's a whole host of places you should be getting ground but you don't seem to be. What are the voltages on your transistors? Did you triple check all ground points on the layout with your multimeter?

Second, there are two types of regulators, the "L" which doesn't have the heatsink and without the "L" and they have opposite pinouts. If grounding the center pin doesn't fix it, you might want to turn the regulator around.

The chip is not a voltage inverter. It's a charge pump. It boosts the voltage on the audio path to +18V.

Finally, can you snap a clear picture of the underside of the board?

EDIT: Remove the PT2399 while you're getting the regulator working. Feeding it 9V could result in a dead chip. Get the 5V working first and then you can put it back in. Have another PT2399 ready to go just in case this one fried.

koky

Here is a better pic of bottom side
http://i608.photobucket.com/albums/tt164/kokySX/Picture_zps3fd18088.jpg
You are right center pin is not connected to ground . Rookie mistake.
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

Quote from: koky on December 21, 2013, 12:50:57 PMRookie mistake.

Eh, I miss stuff all the time...

Your perf work is really good. Mine rarely looks that tidy. :)

koky

#4
Grounding middle pin of Q3 - solved. Now I have 5 v on pin1 2399.
There is bypass and wet signal.  :D
But... like always happens to me ... I don`t have spare 2399 and tomorrow is Sunday and ##*@#!*!#!# I`ll have to wait till Monday.

"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

koky

#5
Bought some new IC`s today and here is what is going on after I put the new one - oscillation even with the bypass (preamp) and sound is kind of dull and distorted. Meanwhile I realized that one of the pins of Q2 is not soldered - now it is. These are the missing solder joints http://i608.photobucket.com/albums/tt164/kokySX/ad27aeb2-2b64-49b3-aa62-a2ae6714c97e_zpsf94e8e45.jpg
Then I forgot to put Q2 back and plugged the pedal again to see if this is the problem. WOW what a nice clean sound on bypass and wet ... DANG ... I saw that 2n5457 is not on its place. Put it back in and oscillation is back.
Any suggestions what to do now?

And Midwayfair thank you for kind words. It feels so good to receive approval from someone like you.
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

Quote from: koky on December 23, 2013, 01:54:16 PM
Bought some new IC`s today and here is what is going on after I put the new one - oscillation even with the bypass (preamp) and sound is kind of dull and distorted. Meanwhile I realized that one of the pins of Q2 is not soldered - now it is. These are the missing solder joints http://i608.photobucket.com/albums/tt164/kokySX/ad27aeb2-2b64-49b3-aa62-a2ae6714c97e_zpsf94e8e45.jpg
Then I forgot to put Q2 back and plugged the pedal again to see if this is the problem. WOW what a nice clean sound on bypass and wet ... DANG ... I saw that 2n5457 is not on its place. Put it back in and oscillation is back.
Any suggestions what to do now?

What type of oscillation? power whine (super high pitched), or the PT2399 is oscillating a lot?

What are your voltages like now?

koky

I`m not quite sure but it sounds more like high pitch.
   1. 10.50  5. 0.30
   2. 4.60    6. 4.77
   3. 0.00    7. 5.16
   4. 0.14    8. 10.56

   1. 6.07   16. 4.27
   2. 3.03   15. 0.10
   3. 0.01   14. 4.89
   4. 0.01   13. 3.05
   5. 3.52   12. 2.21
   6. 3.04   11. 3.05
   7. 1.86   10. 3.05
   8. 3.97     9. 0.30

78L05  IN - 10.60 GND - 0.01 OUT - 6.09
bc549  LEFT - 8.50 MID - 2.54 RIGHT - 8.55 (Top view like on the build doc)
2n5457 TOP - 5.70 MID - 0.40 BOTTOM - 0.00 (Top view like on the build doc)
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

Is the emitter resistor on your BC549C grounded? The emitter voltage should be maybe a couple of volts at most.

Your 2N5457 should also have something more like 10V on the collector.

Your multimeter seems to be reading about 10% too high, too. Might be time to change the battery.

After you fix the emitter on Q1:

What are you powering it with? Try sticking a 100R in series with the power supply (use alligator clips or something if you have to). Does the noise get quieter?

Also, do you have any delay? Or is the chip still motorboating?

koky

Witch one is emitter resistor of Q1? If 1K then it is grounded witch means that my trany is reversed isn`t it?
bc549  E - 8.17 B - 2.10 C - 7.09 (plugged like on build doc) C - 8.17 B - 2.10 E - 7.09 (reversed) if that makes any sense! 
2n5457 Drain (E) - 7.05 Source (B) - 0.35 Gate (C) - 0.00
DMM fixed.

I`m powering it with old router power supply only reversed -/+.
Don`t have any delay and the chip is still oscillating.
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

Quote from: koky on December 24, 2013, 04:26:02 AM
Witch one is emitter resistor of Q1? If 1K then it is grounded witch means that my trany is reversed isn`t it?

I drew the layout for a 3904. The BC549C has a reversed pinout. The emitter of whatever transistor you use goes on the right.

If you can set up an audio probe, I need to you follow the audio through the schematic and tell me where the oscillation is introduced. Set the repeats to zero for now.

Schematic is here for reference:
https://docs.google.com/document/d/1P7uOYFRH6ZW5eGoquhAiMQMyUU76bod_gNKkiSlPNJM/edit

koky

Shame on me but I don`t know how to follow schematics! ::) I am in process  of learning all this.
But I have come to this:
1. As soon as I plug Q2 in its place and begin to turn Repeats pot oscillation occurs. Delay pot slows or fastens oscillation.
2. If Q2 is out nothing of the above mentioned is happening.
3. I think that somehow I managed to solder the switch wrong. What I mean. When switch is off (LED not light) see point 1. and when switch is ON (LED light) I THINK it activates preamp section of the pedal.
Speaking of this do you think that the problem is Q2?
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

koky

After some reading I decided to sub 2n5457 for BF245A. A little step forward because when I turn R and D pots I don`t have immediate oscillation. I`ve  found also that I soldered Mix pot maybe wrong because when I turn it CCW oscillates -> CW stops oscillating. Pot is B50K - how to make it B25K?
And suddenly when I was playing with trims I touched with screwdriver pin 13 (?) and I heard repeats. But not repeats of guitar but like when you short something. All pots were full CW and I started to turn them. They behaved like they should ( I have had Sea Urchin and I know what to expect)
What do you think?
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless

midwayfair

Quote from: koky on December 24, 2013, 12:04:31 PM
After some reading I decided to sub 2n5457 for BF245A. A little step forward because when I turn R and D pots I don`t have immediate oscillation. I`ve  found also that I soldered Mix pot maybe wrong because when I turn it CCW oscillates -> CW stops oscillating. Pot is B50K - how to make it B25K?
And suddenly when I was playing with trims I touched with screwdriver pin 13 (?) and I heard repeats. But not repeats of guitar but like when you short something. All pots were full CW and I started to turn them. They behaved like they should ( I have had Sea Urchin and I know what to expect)
What do you think?

The repeats pot is a HUGE reason you're having the oscillation issue (also, it sounds like it could be backwards ... pin 1 should be ground). Anything above 25K will oscillate at like 9:00, and it should be an audio taper for best performance. The reason it's a smaller value -- and oscillates easier -- than other PT2399 delay designs is that there is far less filtering in the delay path, so more signal is present. The smaller value on the pot help correct this without relying on extra filtering.

Here's the required reading for calculating the resistors needed to make your 50K pot a 25KA:

http://www.geofex.com/article_folders/potsecrets/potscret.htm

koky

Managed to make that pot 25k. Thank you for the link.
I found another mistake. I have soldered both lugs of 220nF (blah). Now it`s how it should be.
But allow me try to explain what is going on.
1. Switch OFF -> Nice warm sound and when i turn Bias CW or CCW I have respectively more or less "room". I guess this is because of increasing or decreasing voltage if I understand the purpose of this trimpot right. If I turn LEVEL pot it goes quieter or louder.
2. Switch ON -> LED`s are light -> All of the above but there is no delay only oscillation when I play with rest of  the pots. I still have guitar signal going thru only that it is NOT delaying.
Prove me wrong but I think that somehow the signal bypasses IC2.

And Merry Christmas to all of you
"When you want something in life, you just gotta reach out and grab it." - Christopher McCandless