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NPD - Lovetone

Started by LaceSensor, July 01, 2012, 11:01:17 PM

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Haberdasher

Jim that is awesome.  I hope you get it going!
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electricstorm

Thanks guys, really appreciate the encouragement.

I have verified the LFO and am working on verifying the Delay section. At the moment, no delay, I'll figure it out, hopefully. May be asking questions about the BBD's and LDR's.

Haberdasher, couldn't have got this far without your help on the boards! It almost looks like the original!! I did use all 1% resistors as that is what I had here and didn't want to order 5% resistors. Hopefully it won't affect the sound. Once this is done, someone will need to compare it to the real thing, but we'll cross that bridge when we get there. I think Bean said in a seperate post somewhere that he wouldn't mind building one.

I'll keep everyone posted and when I get close to a fully functioning pedal, I'll make a seperate build report.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

LaceSensor

Quote from: electricstorm on January 10, 2013, 10:56:12 PM
Thanks guys, really appreciate the encouragement.

I have verified the LFO and am working on verifying the Delay section. At the moment, no delay, I'll figure it out, hopefully. May be asking questions about the BBD's and LDR's.

Haberdasher, couldn't have got this far without your help on the boards! It almost looks like the original!! I did use all 1% resistors as that is what I had here and didn't want to order 5% resistors. Hopefully it won't affect the sound. Once this is done, someone will need to compare it to the real thing, but we'll cross that bridge when we get there. I think Bean said in a seperate post somewhere that he wouldn't mind building one.

I'll keep everyone posted and when I get close to a fully functioning pedal, I'll make a seperate build report.

Jim

Hi

Once its done (and I intend to help you with the parts and voltages) I would be more than happy to compare it to my original, if you were happy to ship it to the UK for me to do so.

Ian

alanp

That is a scary, scary board, and I kinda want one now. Gaaah.

What is the '1200' component in the top right?
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electricstorm

QuoteOnce its done (and I intend to help you with the parts and voltages) I would be more than happy to compare it to my original, if you were happy to ship it to the UK for me to do so.

When it's finished, we can work something out. Thanks for the offer!

QuoteThat is a scary, scary board, and I kinda want one now. Gaaah.

It really isn't that bad as far as a build. Just have to take your time and check your work. The verification part is a bit time consuming though.

Quote
What is the '1200' component in the top right?

It's an isolation/matching transformer for the "Time Out" portion of the pedal.
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

LaceSensor

Hi

Here are my updates to the fairly long list of debugging points.
I didnt get time to take the PCB out, requires desoldering and lots of screws. I will do that as soon as I get time. For what its worth here are most of the other answers.

Supply voltage was 11.2v. That shouldnt really matter - you can assume supply and 1/2 supply voltages and go from there. For some reason none of my PSUs wanted to put out 9v on my bench. My decent regulated one is all wired into my pedalboard and I have rehearsals tonight and show on the weekend so I cant take it off right now.


Here is the list:

Daughter board:

1) Color of the LED. I know it is water clear, but is is a high
brightness green LED?

-   Don't know how to answer that exactly. Its  Clear Green and says HB on the PCB. So yeah, it's a high bright in my opinion.

2) What are the voltages at all pins for both IC's?

-   1      0v      7.57v
-   2       2.75v      2.79v
-   3      3.56v      0v
-   4      6.97v      3.04v
-   5      7.48v      3.52v
-   6      2.99v      3.63v
-   7      4.29v      3.66v
-   8      4.28v      7.04v


3) What is the voltage on pin 2 of the 22k trim pot (center pin/lug)?
-   3.77v

4) What is the voltage on the banded side of the vertical diode (far
left hand side of the daughter board)?
-   0v
- to the "right" of the horizontal diode its reading ~7.5v

5) What resistance is the light and dark resistance of the LDR?
-   not desoldering unless absoutely essential, sorry.


Main board:

1) What is the voltage at pin 2 (center pin) of the 22k trimmer?
-   2.79v

2) What are the voltages of each pin of IC1?
-   1   9.20v
-   2   5.07
-   3   4.7-6.0 approx fluctuating
-   4   10.5
-   5   5.25
-   6   5.06
-   7   4.6 – 6v fluctuating
-   8   3.5 – 7.5v fluctuating
-   9   5.27v
-   10     5.22v
-   11    0v
-   12    4.93v
-   13    5.18v
-   14     5.19v

3) What are the Emiter, Base, and Colector voltages of each transistor?
-   Gonna take too long to measure right now...

4) What is the value of D2 (1N4148 or something else. May be a zener)?
- requires board removal, see above

5) What are the values of the two diodes in front of Q9 (the rats nest)?
- requires board removal, see above

6) What is the value of the cap in front of Q9 (rats nest)?
- requires board removal, see above

7) What resistance is the light and dark  LDR's (LDR1, :LDR2, LDR3)?
- requires desoldering, see above

8) Do the LDR LED's (LED1, LED2, LED5) go completely out when oscillating?

-   Depends on the position of the manual control for LED1. For the other two, controlling the tremolo, this is a fixed depth, so they stay the same medium bright regarless, and just flash with the rate control. Only oscillating when Space (Red) is engaged.

9) How bright do these LED's get (do they get bright or just dimly lit)?
-   See above.

10) Does the LED for LDR3 (far right edge of the board. I believe it
is used for the Space switch, not sure) oscillate or does it just come
on when used?

Is it bright or dimly lit?

-   Only on when Time (Green) is engaged. Medium brightness.

11) Is there a second BC397B and if so, what is the location of it
(Q14 is the first)?
- requires board removal, see above

12) If there is no second BC307B, can you confirm the following:

BC549 - Q1, Q2, Q4, Q6, Q8, Q9, Q11, Q12, Q13, Q16, Q17

BC307B - Q14 (obviously)

J113 - Q3, Q5, Q7, Q10,Q15

- requires board removal, see above

13) If you have it, What is the light and dark resistance of the light
jack (I believe it to be 100K dark, but not sure)?

14) You may need to download the latest wiring diagram from
electristorm's dropbox for the following:

Confirm wiring connections, if incorrect, where does the incorrect
wire connet to?
- requires board removal, see above

If the wiring diagram is correct and if I have a connection going to a
designator that is incorrect (for instance, I have the Time Out jack
connecting to the OEP1200 transformer. The designation I gave them was
"C" and "F") would you provide the correct designation?

- requires board removal, see above

15) On the outside of the flanger, are the Red, Green and Yellow LED's
bright or dim when on?

-   With the settings as you want them, Loop (yellow) is always on but not bright when engaged. Time (Green) is on and dim when engaged, Space (Red) is on and Dim when engaged. Switching the LFO to square wave for the Space increases the brightness a tad.  Increasing manual and or depth increases the brightness of Time (Green).
-   LED 1 on the daughter board is the Time LED (flange / delay LFO control). IT behaves in the opposite to the Time footswitch LED when Manual is adjusted.

When you take the voltage readings for the transistors, IC and any
other voltage, set the controls to the following:

Manual, Depth, Rate, I/P Gain - Fully CCW (counter-clock-wise)
Reaction, Action - 12 o'clock
LFO selector - setting closest to the controls ( first selection from the top)
Mono/Stereo - Mono mode
All footswitches - OFF (or what you consider to be off)
No input signal.
Nothing plugged into any of the jacks except the power jack.

Thanks A LOT Ian! This is greatly appreciated!!!


You're welcome. Thanks for your patience.

electricstorm

Thanks again Ian! 

At least with the voltages (and setting my PSU to 11.2v) I can do some checking around the IC's.
I had been using 9v (the manual says 12v MAX) for some testing. The LFO is working, I get a
square and triangle wave output, so I assume the transistors are correct for this section. I have
also passed some signal through the I/P Gain section, although a little weak. For the time being,
I am using a tone generator for my signal input and an audio probe for tracing signals.

Missing from the list was C6 (tatnalum cap), need that value too when you get time. I have a
10uF, 35v tant in the C6 location now for testing purposes, but it may not be the right value.

Futurlec is holding me up on some of the LDR's I ordered back in December.    For now, I'll use
what I have (500k dark, 20k - 30k light) although it may not have a very large sweep.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

LaceSensor

The diodes all appear to the 1n4148 type but its almost impossible to tell 100%. They look very similar to those in the dopp, and 1n4148 work there.
The cap in front of q9 is a 10uF / 35v electro, or if you mean the box cap near there, 47nF.

Regards

electricstorm

The cap that was soldered in with the two diodes and the resistor was the one I was talking about along with the tant at C6.

Thanks for the info! Very much appreciated.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

electricstorm

I have assembled the Flange ? as if it were to be boxed. All switches, jacks and wiring has been done. The I/P Gain, Depth, Rate, Manual, Action, and Reaction controls are working (after a few bad starts, will mention this later). It is flanging and has tremolo. The bias is a bit touchy on the BBD's, but I think I have it set correctly.

It produces some very unusual sounds along with the flanging. The Action and Reaction controls are "Center Off" type of controls, moving them in either direction produces slightly different sounds. The loopage foot switch only allows you to switch in or out the FX loop, nothing more. The Time foot switch seems to control the flanging portion, but also seems to interact with the tremolo. The Space foot switch seems to control the tremolo but also seem to interact with the flanger portion. I need to do some more experimentation with it.

Futurelec is holding up my order that I placed back in December. I had ordered several LDR's from them to try in the flanger. The only LDR's I have at the moment only produce a narrow "phasing" or "sweep range". They are about 5k - 10k light and 500k dark. Need 10k - 20k light, 1m dark at least and maybe something in the range of 20k - 50k light, 10m or 20m dark.

The main board LED's are diffuse green. The daughter board has a clear LED marked H.B. and have assumed it was a high brightness LED. Using a high brightness LED there causes sever ticking in the audio. I have three different diffused and tinted green LED's and tried those on the daughter board. One of them mad the ticking minimal. Now you can only hear ticking slightly when using the square wave portion of the LFO. It might be tolerable. Anyone have any suggestions?

Now, the "few bad starts" I mentioned had to do with the BBD's. I had ordered sixteen sets of MN3102/MN3207 combos from Polida on eBay. I thought I had blown the BBD's and decided to check them out in an old Radio Shack delay I had laying around (uses the same BBD's). All of the MN3102 worked fine, but out of 16 MN3207's, only four passed a delayed signal. The rest only passed a "Dry" signal. Anyone else have any problems like this before? Out of the four that were good, the delay time was shorter on them than than the original MN3207 from the RS delay. All of the MN3102's would drive the original MN3207 with no problems. I am currently using the original MN3207 from the RS delay in the flanger for now.

The substitutes at Smallbear, does anyone know if they will plug right in or do they need different voltages? I know they are pinout compatible, but not sure about voltage compatibility. Need to find some datasheets on them.

This is as far as I have gotten on the project so far. Will post some more pictures soon.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

LaceSensor

cool update
the clear green LED On the daughter never goes that bright in the real unit, so try other ones. I found when doing the work on the DOPP that diffuse green LEDs worked well  - check my build doc for that for some hints and tips on experimentation.

With regards the flange (Time) and trem (Space circuits) they are highly interactive when both engaged, this is to be expected. on its own the Space circuit is a fixed depth, square or sine wave LFO tremolo, with only the rate (and I/P gain, which is universal and "always on" even in bypass) controlling it.

The Action and Reaction controls are centre off as you suggest - they select the amount of resonanace and of what polarity the feedback path is, and then the amount of regeneration / feedback. Biased at 9v you'll find you get a bit less range out of these controls. At 12v you'll get more "action" outta the usable sweep before onset of feedback. Also, you will find that if you have one control positive, the other negative, and vice versa, feedback will kick in earlier. This is fun of course, but is a frustration when "just" trying to get a normal chorus or flange tone outta the thing.

The Loop is behaving normally. The recommended "cool thing" for this is to add a digital delay on 1 repeat into the loop. The pedal will then turn this into an analog sounding delay with repeats controlled by the feedback (reaction) control.

I assume part of this was already known as I think the manual is online, but if you need a copy just ask.

as for the mn3207 issue, I beleive the Cool Audio reproductions are pin for pin, but might be 9v limited?

electricstorm

The testing, up until last night, had been done with a tone generator. I hooked up my guitar to it last night. Pretty neat and unusual sounds out of it. I need to do some more testing with it, especially when I get the LDR's I'm waiting on.

As for the ticking with the square wave portion of the LFO, I'll try some things there. Although I do not yet have that little bundle of parts in the lower right-hand corner of the board soldered in yet (the resistor, cap and 2 diodes). That may be part of the ticking problem as it is in the return path from the daughter board. Otherwise, not sure what that part of the circuit does just yet.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

electricstorm

#72
Here's a photo update on the Lovetone Flanger:

Top side (the LED/LDR is missing from the daughter board)


What I call the rat's nest


Back side


Switches



The big black things toward the bottom center are Vactrols (VTL5C3) that I am trying for now. So far, they sound better than the LDR/LED combos but that may be due to the fact I don't have all the LDR's yet to try. The Vactrols don't work for the daughter board. It kills the delay and re-setting the bias does nothing for it.

Using a green diffused LED on the daughter board seems to eliminate the ticking. There is a thumping sound only on the square wave selection of the LFO. The manual mentions something about thumping when selecting the square wave. I guess this is what it what it is talking about. The triangle wave gives a decent sweep, but maybe it could be better with different LDR's. Just a guess.

I have obtained some flanger sounds but can't seem to nail the chorus sound yet. The rate for the LFO is selectable from an extremely SLOW rate to an over-the-top fast oscillation. At the upper end of the rate control I can get a sort of ring modulation sound.

I added the 1N4148 diode to the D2 location and will re-test this later.

That's about it for now.

Jim
ElectricStorm

No current affiliations

Lovetone Flanger  https://www.dropbox.com/sh/3v4twi2sbs0l5p7/1Ep9NbRE2T

TNblueshawk

Y'all are just killing it.

You could email Steve at Smallbear to ask about the pin out. Tell him what you are doing and I think he will respond to you quickly. I know many folks who have emailed him for info such as this.

Damn, if I had the LDR values I'd send em'. The one time I ordered from Futurelec was the last. I'm not waiting 8 weeks for a parts order in the year 2013. For a custom amp/guitar, sure I'll wait but not parts  ::)

John

jimilee

That's a lot of knobs Jim! Can't wait to see it go.
Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.