Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - HamSandwich

Pages: [1]
1
Open Discussion / Harbinger 1 donít like the daisy chain
« on: October 20, 2018, 01:14:41 PM »
Odd Harbinger 1 behavior. Iím using the Dunlop 18V adapter for it. When I power the pedal directly from the adapter, it works fine. I have a Aion colorsound powerboost that I plug into the 18V adapter as well, which works ok. So I got a daisy chain and plugged them both in. Boost works fine. Harbinger 1, all the lights light up, LFO is going, sound is passing, but there is no vibe, just clean signal. I thought maybe itís drawing too much power with both pedals, even though everything seems functional. But the harbinger 1 still doesnít work when the boost is disconnected. When itís just adapter into the daisy chain into the pedal, I still get the same symptoms; LEDs are on, LFO is going, only clean signal when pedal is engaged, but no vibe/movement. Vibe comes back when daisy chain is removed from equation, even though the daisy chain is essentially acting as an extension cable for the adapter. Thoughts? Thanks!

2
Open Discussion / 250mH inductor?
« on: October 06, 2018, 12:35:05 PM »
Hola,

Iíve read the great vox wah / precursor to the Clyde McCoy was a similar circuit but with a 250mH inductor and the 100k series resistor removed. Any leads on where to find a 250mH inductor? Iím located in CA - USA. Looking mainly for that Zeppelin I kind of wah.

Thanks!

3
Open Discussion / Jig to hold enclosure while drilling?
« on: September 08, 2018, 02:15:53 PM »
Looking for advice on how to hold an enclosure down while hand drilling.

Iím tired of banging up the enclosure, scrapping the paint, banging knuckles on spinning enclosures. I have a few C clamps but I use a plastic folding table and it isnít really cutting it, especially when drilling holes on the sides.

Is there any jig that can do these things? Thanks!

4
General Questions / Beginning My First Madbean Builds!
« on: August 08, 2018, 09:24:45 PM »
Hard to believe I signed up for this forum in 2015 and never bought a PCB from the shop. I got an Aquaboy PCB second hand to build back in 2015, but nothing from Madbean himself. Ordered a Harbinger One and a 4:1 Compressor on Monday and they were in my mailbox today, Wednesday. That is totally absurd. Fastest shipping? And best yet, they were in THE SAME SANDWICH BAGS I use for my sandwiches.

Iíve never played a compressor, but this one seemed like a good jack of all trades comp to try out. I have a shin-ei univibe somewhere in storage, but itís huge, is a pain, and I donít really want it sitting around, so I wanted to build the Harbinger as well. Going to do an 18V adapter on the Harbinger with the smaller bulb from SB. Unsure how Iím going to light shield yet.

Will update the thread as I go along! Iím very excited. Iím thinking of finishing the pedals in ďBook of the New SunĒ theme.

Thanks Brian!

5
General Questions / Aion Plasma Colorsound Powerboost debug help!
« on: July 28, 2018, 12:51:43 PM »
Hola - thanks for your help.

I'm attempting my second power boost, this time from Aion's Plasma project.

https://aionelectronics.com/wp-content/uploads/2015/05/aion-plasma-colorsound-overdriver-documentation.pdf

I attempted this pedal on perf in 2009 and it didn't work. Now, 9 years later, the second try still doesn't work  ;D

I built it based on the Power Boost parts in the build doc. Things I changed:
- I'm using a MAX1044 based voltage doubler on perf, pins 1/8 connected, to get 18V.
- I left of D1 because it's present on the voltage doubler.
- I used a 10kA for the Gain pot rather than the 1kC (acceptable based on the build doc and the original pedal).
- I ran the the CLR directly from the power jack as to not draw the limited mA from the 1044 to power the LED. LED does work in this set up. So rather than the board LED switching, it goes power jack -> resistor -> LED on board -> Switch -> Ground
- Not really a mod, but C12 is an electro in the powerboost and the PCB doesn't have a polarity marked, so I put the negative side towards the volume control per some schematics of original units I've seen online.
- Also not a mod, but I'm using enclosed jacks, so the enclosure isn't grounded. I've grounded jacks, switch, PCB and power jack via wire. Don't think that's an issue, but thought I'd provide as much info as possible!

Voltages:
1Spot
9.45 V

Supply to board
18.04 V

Q1 2N5088
Q1
C 5.83
B 3.66
E 3.12

Q2 2N5088
C 9.99
B 5.83
E 5.18

Q3 2N5088
C 10.10
B 2.64
E 2.02

There is some issues with biasing the transistors. All three trimmers are basically turned all the way down. For Q1, I can't get it to go any lower than the 5.83V (build doc says 5V). Q1 and Q2 are almost all the way down, but have a little bit more travel on the trimmer before they bottom out.

It does pass sound, the EQ and the volume control work, but the gain control does nothing - no boost. With volume maxed, and the EQ set in the center, I get a slight volume drop. For testing, I've been plugging the pedal directly into my focusrite into my PC. I'd think if this thing was functioning, I'd be able to clip the input stage of the focusrite, but it isn't happening.

I have checked all resistor values using their color bands and all capacitor ratings. I have checked the pin out the transistors (they are also facing in the direction of the silkscreen). Working on getting a photo of the board up.

Any and all help is appreciated! Thanks.

Thanks,
Matt

6
Open Discussion / Hypothetical Flanger Questions
« on: July 13, 2018, 06:29:57 PM »
From what I understand, your basic through zero flange is taking the dry signal of a flanger and slightly delaying it so the modulating flangeíd signal gets to slower delay speeds than the delayíd dry signal.

So what happens if you split the signal into three - one dry signal, and two then paths into flanger circuitry, but have the flanger driven by bipolar LFOís? So as one path increases in delay time, the other decreases. Once the signals are summed, would something interesting happen, or would there be a lot of cancelation?


7
General Questions / H11F1 with LFO?
« on: March 24, 2018, 10:17:54 PM »
Anyone had success using an H11F1 with an LFO for use in a tremolo or delay mod? Canít seem to find any projects using them for this purpose. I see the multiple. Uses one for the ramp switch, and plenty of bypass schemes. Does it not easily work in pace of a vactrol when fed a LFO?

8
Open Discussion / LFO / LED Relations
« on: March 10, 2018, 06:11:23 PM »
Or, how to drive an LED with an LFO.

I've been goofing around in LTSpice. Below are four schematics of a couple of ways to drive an LED from an LFO. LFO is 0-5V. The LED specs are If=25mA, Vf=3.6 (not a lotta choices in LTSpice). The opamp can supposedly swing down to ground.



On a DIYStompboxes thread, the fourth schematic was recommended as the LED in the opamp loop gets a constant current in exact proportion to the LFO. I've read that the issue with the first three schematics are that the brightness of the LED won't track with the LFO as it won't turn on until the LFO reaches a certain voltage/current.

So I simulated them and plotted the current.



Note that D1 doesn't appear because it is exactly the same output as D3.

The problem with D1 (and D3 as it's basically the same thing) is the LED won't turn on until it hits that magic voltage number, so you get the big bottoming out in the troughs.

D2 and D4 appear to be similar, but flipped along the x axis. Is it safe to assume the flatline of D2 is because the LFO isn't turning on the transistor at that point?

The clipping looked a lot like headroom issues. So I tried biasing the LFO in the transistor up a few volts and messed with the CLR and base resistor, and it looks like the current tracks pretty well with the voltage from 0mA up to the If 25mA. Besides trying to get 3.1V as a bias voltage, is there anything inherently wrong with this?



The headroom issue also seemed to fix the LED in the IC loop problem. I had to guess at the CLR in this case, as I'm not sure how to determine it in this setup. They both seem to be opperating similarly. Is there any reason that one is better than the other? Real world problems that don't show up in a simulation? Transistor circuit should take up less space than a big ol opamp.

9
How Do I? Beginner's Paradise. / SMPS Project?
« on: January 10, 2018, 07:36:02 PM »
Hola,

Are there any SMPS projects out there? I see there's a few posts here and there about them, but no 'here is the schematic, layout, parts lists' etc. I don't expect to find them on a pedal building site, although Grind Custom used to have one I think, but that seems gone. An available PCB isn't critical, but from what I understand, a good layout can make a huge difference in one of these things.

Ideally it could produce 250-300VDC, and maybe enough current to power 3ish 12A#7 tubes? I'm not looking for one to fit in any particular project, but a basic SMPS circuit that could be used in a number of different ideas.

Thanks for your help!

10
Open Discussion / What to put in old TV Antenna?
« on: July 19, 2017, 09:13:36 PM »
Hello all,

I had an impulse buy of some weird looking rabbit ears, wondering if anyone has any suggestions for effects to put in. I have a single antenna theremin already, so probably not one of those. It's got two knobs and a switch and looks like this



Is there some weird fuzz/theremin/oscillating debauchery that fits the bill?

Thanks

11
General Questions / Current Lover LFO mod
« on: March 04, 2017, 09:29:52 PM »
Hola Everyone,

I'm looking to work on a PWM LFO, and I wanted to test around on the Current Lover / Electric Mistress. I'm not sure how to filter the PWM into an analog voltage, so I was going to use a Vactrol. Might help with sharp edges as well. I was thinking somewhere in the R28/29 vacinity. Any tips? Thanks!

http://www.madbeanpedals.com/projects/CurrentLover/CurrentLover_2015.pdf

12
Open Discussion / 3 Way Amp Splitter
« on: February 05, 2016, 02:08:09 PM »
Hola

Nothing too new here, but I thought I'd see if anyone with experience could comment on this schematic for a 3 way splitter. Used with at least 2 amps, possibly three, or used to send to a DAW, etc. Loops added to each channel for using effects on specific outputs.

I don't think all three need to be isolated/ground lifted, even if it's three amps. Is that correct? I was looking at the radial switchbone, which seems to only ground lift and correct phase on one output. Would the output without the transformer's sleeve be grounded to the enclosure, or would that need isolation too?

Thanks for any advice.



13
Open Discussion / Dear Person who PM'd re: Echorec
« on: February 02, 2016, 05:37:10 PM »
Sorry for taking out the personal ad, but a member here PM'd me about an echorec, and I had PM'd back, but it seems to have gotten erased in the latest round of crashes. Shoot me another PM if ya want!

Cheers

14
Open Discussion / Where do you buy bulk cable?
« on: April 27, 2015, 06:47:04 PM »
To anyone who makes their own patch cables, etc. Where do you buy bulk cable? I'm looking to make a bunch of 3.5mm or 1/8" cable, and figure they probably sell it at places that sell the 1/4" cable, but I'm not having much luck even finding that. Not really looking for George L's or Monster cable, cheap bulk please. It's used for remote switching, so not a lot of fidelity needed there.

Is there a certain gauge that goes with the 3.5mm plugs? Tayda has them but they don't have a lot of info about them.
http://www.taydaelectronics.com/review/product/list/id/1933/
A specific gauge may unlock the key to finding the stuff. I could just buy a 75ft cable and cut it up, but wanted to see what the other options are.

Thanks in advance.

Pages: [1]