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Topics - whitebread47

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16
I populated this etched board over a month ago, it didn't work and am just now getting to troubleshooting it.  Indicator LED and bypass work fine, but there is no effect when engaged.  I've now quadruple-checked the wiring, everything looks good.  I will continue checking, though.  I can't find any cold solder joints or traces, but ran a pick through just to make sure.  I'm getting GND continuity and 8.95v to the center pin of the DC jack.  No substitutions were made for the components, and I've triple-checked values for good measure.

I did accidentally lift off the negative lead LED and SW pad, so I soldered those respective leads to each other since the trace between them was connected and isolated as well, so I don't think this could cause a problem since the switch and LED appear to be functioning properly.  The clipping LEDs are not lighting up at all.

Now for voltage readings.  Here's what I'm getting on the CA3130EZ:

1 = .07    8 = 4.26
2 = 4.10  7 = 8.25
3 = 2.95  6 = 4.11
4 = 0.00  5 = 0.00

From my limited understanding (and reference to the datasheet) this looks pretty close to what it should be (I think input should be around 4.5v and output around 9v?).  Please correct me if I am wrong, however, as I'm used to dual opamp readings.  Since pin 4 is V- and pin 7 is v+, should I be getting -8.25 at 4?  On the schematic, both 4 and 8 go to ground, so I'm a little confused on how voltages should read here.  ???

Also, the drain of the 2n5457 is getting 8.19v.  My uneducated guess is that I may have a grounding issue, though I can't seem to find where.

I have to step away from my workstation to run an errand, but I will take some close-up pictures when I return.  Thanks in advance for any suggestions or tips!

17
Open Discussion / Soldering Iron Recommendations
« on: May 29, 2012, 08:47:11 PM »
Some of you may recall my "soldering iron woes" thread from a couple of weeks ago.  Last time, my iron quit working after being accidentally left on for about 6 hours.  No biggie, I replaced it the next day with (unfortunately) the same one.  However, my recent one has quit working all of the sudden.  It worked last night, I tinned it and unplugged it as usual.  Went to fire it up today and...nothing.  :-\

Up to this point, I'd been going the quick and easy route by purchasing Weller 40 watt irons from Home Depot.  It appears that these just don't last very long.  I also think I may need more like a 25-30 watt iron or one with variable temp.

So my question is this:  What is a good, reliable iron?  I've heard good things about Hakko, while I initially thought Weller was a proper product.  I don't have a whole lot of budget for one, so I'm seeking the best value while maintaining quality.  Under $100 is ideal, closer to 50 or 60 to be honest.

Though I've had some shoddy tools from there, I have a local Harbor Freight and recall their prices being pretty low.  Can anyone verify that they have decent irons, or maybe someone can testify to their iron they got from there and provide a model #?

Many thanks in advance.

18
Build Reports / A Blue Serendipity
« on: May 26, 2012, 04:33:27 PM »
Got this etched board in a trade (Haberdasher etched).  Overall, this was an easy build and a fun one.  I got to squeeze into a 1590B, which makes me happy.  The enclosure is from Mammoth, pre-drilled and painted.  The only sub I made was the IC, which is a JRC4558 in mine, sounds great.  Oh, and I didn't have any 3n3's, so I subbed a 3n9 for C4.  I ran into a little trouble testing it last night, but it only turned out to be a bad joint and a simple grounding issue.

Though I've owned a lot of boutique brand OD pedals, I've never desired or played a Zendrive.  Maybe the demos just weren't great, I don't know.  Anyways, I plugged this circuit in before boxing it and...BAM!  This thing sounds amazing, spanky w/ single note clarity and sustain for days.  I love it.  The knobs are very interactive, and a good many tones can be summoned from this beast.

This is my 6th build thus far, and I think it's the most sturdy and well put together yet as well.  Anyhow, here's some pedal porn.






19
Tech Help - Projects Page / Serendipity: No Bypass, Much Noise
« on: May 25, 2012, 10:07:02 PM »
So I fired up my etched Serendipity build and....nada ting.  I've looked over it a number of times, no solder bridges, correct component placement/orientation, wiring done as illustrated in build documents, etc.  I'm getting continuity throughout, and see no cold solder joints.  I'm getting 8.95v at the DC jack as well.  The IC (JRC4558D) is the only subbed part and seems to be getting reasonable readings (though I don't know exactly what they should be):

1 = 4.49  8 = 8.95
2 = 4.49  7 = 4.48
3 = 3.05  6 = 4.49
4 = 3.05  5 = 4.44

I'm not sure how to measure the transistors (datasheet for Fairchild 2n7000 doesn't use the "BCE" orientation, which added to my confusion).  Basically, two of the leads on Q1 are reading 4.49, one at 4.16.  Q2 shows two leads at 4.49, one at 4.31.  If there's any more information that would be helpful I can get it.  I'd love to learn a little bit here, so feel free to school me on troubleshooting.  I'll see about getting some pics up here soon, but may be going out of town tomorrow.

Thanks in advance.

20
Build Reports / The Sunking That Almost Wasn't
« on: May 19, 2012, 11:21:31 PM »
I got an old ver.3 Sunking board in a recent trade, so I had to get on building it.  However, I accidentally plugged the AC input cord for my DC Brick into the DC jack.  Some of you may have seen me in Tech Help freaking out about my nonfunctioning Sunking some hours ago.  All that was needed was a diode swap and I was in business.  I've owned a couple of Klones before, and this hangs in there with the best of 'em for sure!

The oddball knob is because the knob I was planning to use wouldn't tighten up to the pot for some reason, so this is a temp on the gain pot.

As usual, the wiring leaves something to be desired, but it works and is my favorite build yet (I think it's the 5th pedal I've built so far).




21
Tech Help - Projects Page / Silent Sunking, no LED, no bypass
« on: May 19, 2012, 05:10:26 PM »
I got my hands on an old fabbed Sunking ver.3 a couple of days ago.  I populated and wired it all up and....nothing.

A helpful anecdote:  I went to test it at about 3 in the morning in an area that has terrible lighting, so I accidentally plugged in the cord from the wall that was supposed to go into my DC Brick into the DC jack of the Sunking.  As expected, it did not work when I used the correct cable.  Having made this mistake (yes, it's true  :-[) before on a Klone, I immediately looked at the diodes for observable damage.  None of the diodes seem blown visually.  I substituted the stock diodes as follows:  BAT41's in D1 & D2, D3 is a 1N4739A, and D4 & D5 are 1N4001's.

I also switched out the 2 TL072's and put a new TC1044SCPA in, but to no avail.  I remember when I had my Klone (Sagittarian Charger board) fixed a year or so ago from the same problem, all that needed replacing was the 9.1v Zener and I think the 1044.  I have not replaced the 1N4739 yet, as it doesn't appear damaged like the one I had before.

I've triple-checked my wiring and all checks out.  Also, I'm getting continuity in all the jacks (DC included)  All my solder joints appear to be secure enough (will take close up pics in a moment).  There is also continuity from the DC jack to the positive LED lead. 

As for the "box it before you rock it" thing, I have no testing rig right now, so I do what I call a partial boxing just to ensure grounding.  I basically just connect the footswitch and in and out jacks to the enclosure and ensure that nothing is shorting when I test it, so this isn't necessarily a "boxed" circuit that's been pulled apart.

I'm getting no bypass at all.  I used a 2PDT switch (first tie with those) and 2 of the lugs lifted a tad from their positions.  Of course, I impatiently proceeded after that red flag, so I'm not sure how to check and see if that is working correctly.  Would a ruined switch prevent both sound and no bypass, leaving voltages normal?

I also used my DMM to check voltages.  This particular area is where some assistance is needed.  I have my DMM set on 20VDC and am getting a reading of 0.34 from ground to the DC jack.  I don't know what these decimals equate to or what calculation to perform to test against proper voltage.  ???  I also tested the Opamps, which read as follows: 

IC1 -
1 = 0.16   8 = 0.34 (same as DC jack reading)
2 = 0.16   7 = 0.11
3 = 0.08   6 = 0.15
4 = 0       5 = 0.16
IC2 -
1 = 0.16   8 = climbs anywhere from 0.07 to 0.34 and then drops rapidly.
2 = 0.16   7 = 0.16
3 = 0.16   6 = 0.15
4 = 0.16   5 = 0.16
IC3 (1044)
1 = 0.34   8 = 0.34
2 = 0.01   7 = 0.02
3 = 0       6 = 0
4 = 0.03   5 = 0.17

I'm going to take some pictures once I post this and follow up with those. 

Thanks in advance for any help or advice.  I'm really trying to learn here, so dropping some knowledge on me is truly appreciated!

Pictures (pardon if this is overkill, but I wanted to be thorough):






22
General Questions / 2n5088 Transistor Orientation in LaVache?
« on: May 17, 2012, 01:48:19 PM »
I searched the forum, but still couldn't quite figure this one out.  I opted for a 2n5088 instead of the 2n3565, and the transistor is obviously shaped differently.  To anyone who has used these, when looking at the top (component side) of the board, will the flat side face the left or right of the board?

23
General Questions / Omitting The Boost On LaVache Question
« on: May 09, 2012, 02:47:39 PM »
I'm building a LaVache right now.  I had a Les Lius at one point, and am considering just omitting the boost switch/toggle and drilling the enclosure similarly to the Lius with just the shape switch.

So I have two questions, really:  One, does anyone who has built the LaVache highly recommend using the added boost switch (does it add a significant amount of gain)?  Second, if I want to omit it, would I need to jumper anything or could I just not wire up a switch to the boost section?

Many thanks in advance!

24
Open Discussion / Soldering Iron Woes
« on: May 09, 2012, 01:14:57 AM »
So I accidentally fell asleep earlier with the iron plugged in.  I woke up, noticed, and immediately unplugged it.  It was still good and hot when I did this.  It had probably been on for at least 5 hours.  Later, I decided to solder in some caps that just came in on one of my project boards.  Well, just as I had feared, the iron doesn't heat up at all.   :-[  I guess I burned something out (not sure what, but I don't rightly know the parts that comprise one; seems simple enough).

It was a 40-watt Weller I bought from Home Depot.  So, my question is:  Is there a certain length of time that one should avoid using a soldering iron?  Like, for example, "unplug it once it's been on and used for X amount of hours." 

I'll be buying another one tomorrow I suppose, but would like to avoid burning out any more if I can help it.

25
Build Reports / My Flapjack Build
« on: May 06, 2012, 10:39:58 PM »
This is my fourth build thus far and the most complicated.  Okay, so it is a fairly simple build all in all, but all my builds up to this point had been positive ground, no DC, no LED.  I even did away with my usual footswitch PCB and wired the 3PDT the old fashioned way.  

This has definitely been a build that helped me in building my skills up, though.  It didn't work initially, so I took a day off, came back and found that the ground wire had not bonded properly to the lug on the footswitch; easy fix.  I used an LM741CN and cream pre-drilled 125B from Mammoth.  I was first a bit disappointed that I got top jacks, but it didn't really make building it any harder.  I also opted for the B10k for the Gain pot.  I have a TL071 and a C50k lying around, so I may throw those in for comparison sometime.

As for the sound, it is definitely reminiscent of the Hotcake (I've owned two).  I immediately recognized the quick fizzy decay and unique tone.  The only difference that I can surely note is that the Gain range reacts a bit differently, but that may be because I used the 10k pot.  Everything just below or at noon works well for me through my AC15 (just as the NZ built ones did).

Oops, just realized that I forgot to glue the LED in place (it appears to have fallen back into the box).  :-\ I'll post gut pics after I get that done.




26
Build Reports / My First RangeMaster Build
« on: May 01, 2012, 03:20:07 PM »
This is the third pedal I've built so far, the first with no immediate issues.  The caps were just whatever I had/found cheaply in those values.  The transistor is an OC75 I got from Smallbear.  The wiring is very sloppy, that's my biggest need of improvement I think.  I may order various Ge PNPs, but this one works just fine.  With an overdriven AC15 and boost engaged, I get a nasally Brian May tone for days! 

Man, this hobby is addictive.  I can't wait to show off the Flapjack and Yellow Shark I'm building, and I plan to spend more time with my wiring on those.  ;)



27
Open Discussion / Replacing Copper Foil Pad On Etched Board?
« on: April 26, 2012, 09:26:52 PM »
Hi folks,

Up until now I have only worked with fabbed pcbs from madbean, but am now working on one of the etched boards I got from Haberdasher.  He did a great job on them, but I botched a pad yesterday.  The copper foil must have had too much heat applied to it from the iron and it lifted the pad and a small section of the track.  What I'm wondering is if I bought some copper foil tape and meticulously cut a small piece and connected to where the one I overheated lifted, would the pad work?  It happened in a relatively isolated area, so there's little chance of it touching another track that it shouldn't.

My apologies if this is the wrong section in the forum.  I assumed the troubleshooting area was for pcbs bought directly from bean.

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