Joined: Jun 09, 2007 Posts: 198 Location: portland, or
Posted: Mon Jun 01, 2009 2:43 pm Post subject:
Frequency Shifter Subject description: FrontPanelExpress
jhaible wrote:
I heard about this, too, but never really tried it. I guess I'm wasting a lot of money with tick marks for pots that are made from rotated "I"s and such stuff.
JH.
I have used two colors for legends on a panel. I used dual position switches where the up controlled a completely different function than the down. I used different colors to group the controls. It worked well.
I used the 'scale-o-matic' to make HPGL legends for both full size and 3/4 size. The way the program ran, I had to make one HPGL for the major tic marks, and another for the minor tic marks. I then grouped these together with the hole and number legends. BTW, it really took a lot of trial and error to come up with the right thickness and spacing using this tool.
Thanks, Jurgen. It's just a Front Panel Express panel.
That's the US branch of Schaeffer, isn't it?
Yes. They use the same software - in fact, although most of the original German programming has been translated into English, if you ever get an error message, they're always in German.
jhaible wrote:
sduck wrote:
Most people use the default white infill for all the engraving. Adding colors is a one shot price upgrade - I think 7-8$, then you can add any colors infills you want.
I heard about this option, but had never seen it till now.
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I balance the added cost by saving money with no infills on a lot of it - on this panel, everything that looks white in the picture is actually not infilled - just etched aluminum, which looks really great in real life.
That's what I often do as well. I think it saved me 200 Euros on the the PolyKorg Clone front panel!
Quote:
The way I do panels is actually relatively inexpensive - the cheapest fonts they have, as much hpgl as I can use
I heard about this, too, but never really tried it. I guess I'm wasting a lot of money with tick marks for pots that are made from rotated "I"s and such stuff.
JH.
Yes - I've saved a LOT of money by using Dave's and some other hpgl I've found. Definitely worth poking around on Dave's site, and the modularsynthpanels site for.
I have a question at step 2. Shape 2 is fine - I get the triangle wave with rounded edges, easy to adjust. Shape 1 is odd - here's a picture of what I'm getting - the trimmer adjusts the width of that shape, but it's clearly not what I'm supposed to be getting - ? Any ideas?
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Joined: Feb 20, 2008 Posts: 414 Location: Stockholm
Posted: Tue Jun 02, 2009 1:25 pm Post subject:
I just got my FS1A up and running!
I think it works OK. Probably not. But it shifts the incoming sound up and down when I turn the knobs. Sounds instant sci-fi!
The only problem - it stops functioning after a few minutes. It just fades out slowly.. Need to look into that later. Right now I need to run more sounds through it!
edit: After running my TR-606 through it I can hear that I got massive oscillator bleedthru. Will need to trim it in and hope goes away. _________________ http://www.thehumancomparator.net/
I have a question at step 2. Shape 2 is fine - I get the triangle wave with rounded edges, easy to adjust. Shape 1 is odd - here's a picture of what I'm getting - the trimmer adjusts the width of that shape, but it's clearly not what I'm supposed to be getting - ? Any ideas?
Looks like something overdriven ...
Wrong resistor value somewhere?
JH. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Looks like something overdriven ...
Wrong resistor value somewhere?
JH.
I've taken the board out, and have gone over it. No wrong resistors. Bear in mind that this is a copy of Dave Brown's build (and using his BOM), so there are some resistor changes - specifically R2 changed from 51K to 36K, and R51 is changed from 430 to 51K. There is also a 36K resistor added at pin 6 of U1. Would any of these make this effect? (Feel free to chime in, Dave, if you had a similar problem - probably not though)
I've also gone over the board with a magnifying glass (again) looking for potential solder shorts, but found nothing.
There's always the possibility that I hooked up my probes wrong (!?) - stranger things have been known to happen, and my 21$ ebay scope and diy probes are not exactly surgically precise. I did get step 1 accomplished with no problem. and the second part of step 2, so I know the equipment works to enough of an extant to carry out this calibration.
Joined: Jun 09, 2007 Posts: 198 Location: portland, or
Posted: Wed Jun 03, 2009 9:31 pm Post subject:
Frequency Shifter Subject description: parts changes
sduck wrote:
[Bear in mind that this is a copy of Dave Brown's build (and using his BOM), so there are some resistor changes - specifically R2 changed from 51K to 36K, and R51 is changed from 430 to 51K. There is also a 36K resistor added at pin 6 of U1. Would any of these make this effect? (Feel free to chime in, Dave, if you had a similar problem - probably not though)
I had no problems. The three resistor changes are quite simple. Rather than an attenuator and inverting switch for the exponential CV, I changed it to a reversing style like the linear CV so it's wired similar to the linear CV circuit.
The other change is I used U8A as a summer for the diffout and sumout outputs. Since they are both 10 V pk-pk, I changed the gain to 1/2 so the summation would be 10 V pk-pk.
I see now that the reference designators are repeated between boards. I'll change my website to be more explicit.
Aha! I changed the wrong resistor. I didn't do enough background checking, so to speak, and changed the R51 on the wrong board (1). Hopefully fixing this will get things going. Thanks!
Getting closer. I switched the 2 resistors I had wrong, and managed to finish all the calibrations. It seems to mostly work, except it only shifts up. The big knob (manual) shifts up from approximately the center position, both ways you turn it from there. It's probably just a simple miswire of the pot, but I'm tired and will mess with it some more tomorrow. Everything else seems to work, more or less.
Getting closer. I switched the 2 resistors I had wrong, and managed to finish all the calibrations. It seems to mostly work, except it only shifts up. The big knob (manual) shifts up from approximately the center position, both ways you turn it from there. It's probably just a simple miswire of the pot, but I'm tired and will mess with it some more tomorrow. Everything else seems to work, more or less.
I bet it does shift down.
But if the amount of downshift is higher than twice the fundamental of the input signal, it's shifted "thru zero" and into the negative, and the negative frequencies are perceived just as positives, so you perceive an upshift.
Try the same thing with starting with a very small amount of downshift, and gradually increase the downshift. And, use a familiar input signal such as human speech, and the effect will be very clear.
Thru-Zero modulation is a mind-boggling thing!
JH.
ETA: Of course there could also be a fault somewhere in the circuit, where the spinning direction of the oscillator is changed. I just read you were tired, so what I wrote was my first thought. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
No, it's definitely not shifting down. Although depending on what I put through it, the effect is different also. I've checked the obvious things, like the pot wiring, and it all looks ok. I still haven't checked the various cv ins to see if the problem is pot related or not.
My first suspicion is that perhaps I've misread Dave Brown's wiring chart - I went over it about 35 times to make sure I thought I knew what I was doing before doing the wiring, so I'm pretty sure I got it right, and consulted with him about various questions also. I hope I didn't switch the INV1/INV2 connections to the DIFFOUT/SUMOUT connections.
My other suspicion is that I messed up something during calibration - I want to go over the last few steps again to be sure.
And I just haven't had a lot of time to do any of this - it's been pretty busy here, so I'm just grabbing a few minutes here and there to go over this stuff. I'll get it going eventually!
No, it's definitely not shifting down. Although depending on what I put through it, the effect is different also. I've checked the obvious things, like the pot wiring, and it all looks ok. I still haven't checked the various cv ins to see if the problem is pot related or not.
The upshift/downshift function is hardwired on the PCB, so it's unlikely that external connections are to blame.
U3 separates the sign and magnitude of the linear control. (That is, of manual controls and CVs combined. For now, lets asume there is only one linear CV, from the "Manual" pot.)
"Magnitude" is sent to U4. You can measure that value at the anode of D3. It's always a *negative* voltage (actually, "-magnitude"). It should become zero for center position of the Manual pot (or the linear CVs combined being zero), and it should go gradually negative if you turn the Manual pot cw *or* ccw. I guess *that* part is working on your board.
"Sign" is sent to U2B. This also drives the (BiColour) Dir LED ("DirLD" connector). Here (U2 pin 7 - or just watch the LED) you should see the voltage jump from positive to negative when the Manual pot crosses center position. The sign signal controls J1 and J2, which change the spinning direction in the modulation oscillator. So if you have that switching signal at U2 pin 7, there's probably something wrong with J1, J2, D7, D8, R39, R43.
(I hope this helps. I will probably be away from the internet for a week or so.)
JH. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Ok, I had another go at it tonight. I think you were right originally - it's shifting down just fine, I just had the range knob at the wrong setting for ordinary pitch shifting. I tried a bunch of various signals, and now that I know better how the different knobs interact I can get the sounds I'm expecting as well as a lot of really neat unexpected ones. I'm going to have to add the resistor to the feedback circuit someone mentioned earlier - feedback comes on much too quickly, and having finer control over that would be nice. So I think I'm happy! Thanks for the great circuit, Jurgen!
JH. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
JH. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Here's a demo video I made of my build. There's very little to go on about this unit, to determine if it's working well or not, so I thought I'd post this, and perhaps Jurgen and others can chime in whether this sounds like it's working right or not. It sounds pretty cool to me. Don't forget to press the HQ button!
And the little notes that explain what's going on are really helpful!
And ... apparently that's the first appearance of any of my stuff on youtube!
Thank you.
JH. _________________ "I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
i must layout my Frontpanels.
I don't know FreqShifters so i'm looking for a reference Frontpanel that has NOT omitted any controls.
Is any of the Panles with clear Pictures full equipet ? ( no attenuators or CV ins omitted ) ( outgain attenuation is not important for me )
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