|
Post by tonycamphd on Jan 24, 2016 23:45:43 GMT -6
I'm sure Unit7 was talking about the led legs that i mentioned to you, those are also called diodes. If the tranny's are wired properly? i'd think you still have a cold solder joint somewhere, i scanned everything on your board, and unless id missed something.. it looks right, although i do not see the 1/2 watt 10ohm resistor that I have on mine(might be a litz thing?), anyway, did you reflow the switches as well? when you reflow, put light pressure on the leg of the component, as well as the pad at the same time, don't try to lay solder on top of solder.
|
|
|
Post by ragan on Jan 25, 2016 0:00:04 GMT -6
Man. I just gotta say that with this crew, I almost have the courage to build something. I've soldered a lot of cables and guitar pickups and switches but never built any real gear. You guys are great help.
Good luck, JK. I'm sure you'll be passing signal soon.
|
|
|
Post by porkyman on Jan 25, 2016 1:52:18 GMT -6
are you testing it in the the rack or with a test jig. had a problem with the test jig once. it took me forever to figure out it wasnt the comp i was working on. had a problem from not cleaning the board before too. even though i use no clean solder. it was not visible anywhere, and i went through and retouched everything, but it still didnt work. then i gave it a good scrubbing and it worked. those are the only solutions i can come up with from my limited knowledge... good luck
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 25, 2016 3:53:07 GMT -6
John, all good tips in here. I would also think you have still cold solder joints. Obviously, part of the problem went away just by reflowing. From the first pictures i instantly thought: Solder iron not hot enough, not enough flux. What is the wattage of your solder iron / what solder iron do you have anyway? Is there a chance to give more temperature? Do you have pictures how the board looks now, just like the first ones? Then we could see where you are now with your soldering art. Don't worry, i saw much worse first soldering results. MUCH worse ... actually, some solder joints on your board look already professional. So be encouraged you can sort it out. If the soldering iron is hot enough, you can, with a bit of excercise, solder in a good speed, touching the solder and the pad in one point with the iron and have it done in a second. Many of my broken/cold solder joints in the beginning really just were the result of too weak soldering irons and too little temperature. Many first time DIYers think they should use exactly the temperature recommended and tend to use too low temperatures because they fear to damage the board with the heat. But- an iron that is not hot enough needs much more time to heat up pad and solder, damaging boards or components is more likely if the soldering iron is not hot enough, even if it sounds counter-intuitive.... Also, with these small pads, a properly heated iron can solder them in a second. Literally, and without any hassle. Yes, you can use q-tips. On the back side/solder side you can even use a toothbrush! it cleans up better, Afterwards, inspect the board in an acribic manner, square inch for sqare inch, with a looking glass. Not only on the backside, also on the component side. Don't worry, it will be sorted out, no doubt!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 25, 2016 4:03:16 GMT -6
Btw..... AWESOME, you really started into DIY, and right into a good project that will be very rewarding, so chances are good you stay positive and will have fun with other projects, too. Honestly ... i am really surprised, i somehow did not expect seeing you diving into serious electronics DIY anytime soon - but you do and it's quite a bit bigger than a Bo Hansen DI. You have reason to be proud of what you already achieved in your first project.
|
|
|
Post by unit7 on Jan 25, 2016 4:29:33 GMT -6
The legs on those diodes seemed to be awfully close to the joints of the switches. Some cables on the xformers seem to have melted a bit so if there is bare metal check that there isn't a short. Could be the pic but there seem to some solder residues so use magnifying glass and check for shorts. Keeping my fingers crossed! Can you explain a little further what you mean by the diodes being close to the switches? Do you mean the on the back side, the solder joints might be touching? You mean the red/black diodes? Yeah - so the melt that you see is because I didn't really have a wire stripper, so I melted the plastic coating on the wire a bit and then stripped. Maybe I'll go by a wire stripper and re-solder all of those. I left enough length because I was scared of screwing it up. Do I just use alcohol and a q-tip? Yeah, sorry, as tonycamphd said I meant the legs on the leds, on the backside yes. And regarding the melted coating, I just noticed that on one of the xformers the cables were laying vertically and if the cables are bare there's a risk for shorts. Leaving a bit extra length was probably a good thing so you can cut and resolder later to tidy up a bit.. But hey, big improvement that you got the signal in and the green led reacting! So if that happened after reflowing, then perhaps there are more cold joints. Hard to tell because me too think most joints look ok. I'm sure with some assistance from Jeff, the master on troubleshooting these, you'll sort it out!
|
|
|
Post by unit7 on Jan 25, 2016 4:35:13 GMT -6
Man. I just gotta say that with this crew, I almost have the courage to build something. I've soldered a lot of cables and guitar pickups and switches but never built any real gear. You guys are great help. Well, I guess he's getting a little extra support, for some reason.. Though if I was a moderator I'd give him an infraction for not posting in the DIY section..
|
|
|
Post by matt555 on Jan 25, 2016 7:44:41 GMT -6
Looking good John. I would also ask what solder Iron and solder you are using because you should see an even flow of solder back to front both sides of the board. Definitely when you zoom in you can see a few resistors where the solder didnt penetrate through the board to the front side, and some indeed look like they are cold. Also dont be afraid to turn up and down your soldering station or change tips/sizes depending on the solder joint your working. If a pad or component is bigger or if its on a ground plane (heat will disipate) in the board it will require much more heat and time before the solder will flow freely than say if its a small pad or component leg. I run my solder station around 420 celsius/780 fahrenheit and adjust tip sze and temp for different situations. I use a good quality rosin core solder 0.5mm and clean with IPA. When using IPA take care around switches/pots/poly caps as some builders suggest it can damage those components. Around all resistores, wire connections, diodes, etc.. use liberally (I use old toothbrush) and use more than 1 application as once the flux impregnates the IPA it just spreads the flux around and will leave you with a clean but sticky board!! There are some fantastic videos by a guy on the EEV Blog on youtube (search for soldering as he has like 500 videos) that show soldering for newer builders. Even though I had only done some primative soldering before doing my diy builds his videos definitely helped a lot and gave the confidence needed I also agree with the other posts that your LED legs appear to be touching some of the other components near them so have a look at this too. Good luck and dont let this put you off, once you get it working and the hang of soldering you wont be able to stop DIY! Its so rewarding to build a piece of gear that sounds amazing. Thanks, Matt
|
|
|
Post by Guitar on Jan 25, 2016 8:36:10 GMT -6
Just to echo others I would probably use a little more heat, and a little more solder. Some of the joints seem to not have as much solder on them as I would like. You want a nice round mound (who doesn't? hehehe).
|
|
|
Post by Johnkenn on Jan 25, 2016 11:06:14 GMT -6
Hell - I don't know where this gun came from. It's a Radio Shack wand that plugs directly in to the socket...30 W. Might go to the store today.
|
|
|
Post by Guitar on Jan 25, 2016 11:22:39 GMT -6
Make sure the tip of the iron is clean and shiny silver colored at all times. Some copper wool is a great way to keep a tip clean, but a wet sponge can also work (although it tends to put additional wear and tear on the business end of the iron over time).
|
|
|
Post by jsteiger on Jan 25, 2016 12:12:27 GMT -6
Johnkenn I echo what the other folks are suggesting. I do see some joints that look possibly cold. Like someone mentioned, the fact that a reflow did make some improvement makes me think there could be more. Its hard to tell in the pic but there appears to be a solder bridge between the wiper pad and one of the other pads for the preamp gain Grayhill. Could be a reflection though. I also see that the fader Grayhill pins look better/more solidly soldered than the gain switch pins. Also, the signal flows in and out of the HPF board twice so that has been a common place for signal to stop. Maybe you could get those pins easier now that the assembly has been taken apart.
|
|
|
Post by Johnkenn on Jan 25, 2016 13:11:44 GMT -6
Oh - btw - I'm less proud of myself now.
Went to the store bought some rubbing alcohol, mag glass and wire strippers. Gonna go at it again. I'll post a pic of the back when I'm done.
|
|
|
Post by tonycamphd on Jan 25, 2016 13:47:15 GMT -6
Oh - btw - I'm less proud of myself now. Went to the store bought some rubbing alcohol, mag glass and wire strippers. Gonna go at it again. I'll post a pic of the back when I'm done. Don't be less proud! (unless of course you're referring to your new avy? haha) Remember, with that sharp point tip on your iron, it's going to be harder to transfer heat to the pad and component leg, pre tin the tip with a bit of solder right before you go to the pad, and lay the tip on it's side a bit as you go in, it's a feel thing, the only thing you have to worry about is dropping too much heat on film caps, everything else can take quite a bit of heat before any damage occurs, you are CLOSE MAN! good luck!
|
|
|
Post by NoFilterChuck on Jan 25, 2016 14:03:39 GMT -6
|
|
|
Post by Guitar on Jan 25, 2016 14:57:50 GMT -6
Oh - btw - I'm less proud of myself now. Went to the store bought some rubbing alcohol, mag glass and wire strippers. Gonna go at it again. I'll post a pic of the back when I'm done. Troubleshooting is the hardest and most frustrating part of learning DIY. It can be disheartening, almost heart breaking the first time, but if you keep at it you'll probably be a better troubleshooter and have more and more success as you go into new builds/mods/repairs.
|
|
|
Post by formatcyes on Jan 25, 2016 15:22:54 GMT -6
At least you dident let any smoke out the hardest part is putting it all back in
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 25, 2016 15:51:12 GMT -6
Hi John - guess what - i use a soldering iron from the hardware store around the corner, 16.50€ since my old soldering station passed out after a long, long time. But it is much better, than i expected. I needed one that day, so i bought it. BUT, and yes, it is a big but(t) - 30W like your iron has IS a bit on the very weak side. I once had a 25(!)W Weller iron, that was not cheap and i always wondered why the heck i can't solder well with it. Well, it might be well suited for microelectronics repairs maybe.... Nowadays, i buy no iron below a wattage of 40W. Better is 50 or 60W, which are common values of well suited electronics soldering stations, like Hakko, Weller, Aouye etc... So, nothing wrong with cheap irons, they just might not be very durable due to the heat element construction, but if the tips are right, you can do everything with them that you might need. For a 30W iron, your joints don't look bad - it is just a weak iron, as i guessed. Btw, i also saw the possible short that Jeff mentioned - therefore i wanted to see updated pictures after rework. Stay positive - you *will* get this thing running. Stay proud. You are doing great. Let me tell you my first DIY PCBs i soldered at home looked pretty ugly compared to yours, it was an Alembic type of active bass circuit...
|
|
|
Post by Johnkenn on Jan 25, 2016 18:42:33 GMT -6
Yeah, I just need to bite the bullet.
|
|
|
Post by Johnkenn on Jan 25, 2016 18:48:44 GMT -6
So I was checking everything to the other VP28 with Litz I have (built by Joel Phillips) and I noticed I had R20 and R21 in backwards...which is phantom power apparently. I thought that might have been an issue, so I texted Jeff and before I got an answer back, I decided to heat them up and take them out...Then Jeff says that orientation shouldn't matter. DOH. Damn, that was a bad idea. I don't have a decent solder sucker thingy - just a squeeze suction thingy...The problem now is how in the hell to get the solder out an have a hole to put the resistors back in...I ended up kinda half-assedly soldering them back in...but hey, if the phantom doesn't work off the bat, that's fine. I think I screwed R20 up, so I'm having Jeff send me two more...then I'm gonna have a pro put them in (talking to you Shannon)...
Everything looks pretty damn shiny to me...I'll post a pick in a sec. Then I'm gonna try it again.
|
|
|
Post by matt555 on Jan 25, 2016 18:59:23 GMT -6
Removing resistors/wires/certain components without proper tools is easier than people make out.
Cut the legs if you can so you only have to heat up one leg at a time to remove. Remove remainder of legs by heating with your iron till solder liquifies and pliers one at a time. You will normally be left with a hole filled with solder, no problem thats what solder wick is for. It sucks all the solder up through heat from your solder iron. If at first the solder wick doesnt suck, dip it in some liquid flux to allow the solder to run and suck up faster... Ive had to do this a few times and for me its the best option other than buying the hakko desoldering tool which im saving for... Ive heard loads of stories of people pulling traces trying to get components out but I never have... Thanks, Matt
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 25, 2016 19:03:09 GMT -6
I think I screwed R20 up, so I'm having Jeff send me two more...then I'm gonna have a pro put them in (talking to you Shannon)... Naah, c'mon John. I tell you something... You are best off getting yourself a good soldering iron/station and while you are at it scratch together some dough to start another project. And order a bunch of resistors and the ones you *might* have damaged possibly. (That normally is really hard to do with a soldering iron, btw...) Maybe a small DI project as a rewarding quickie, say, the Bo Hansen with a Lundahl? Something small and useful you can't buy, but sounds good at a good price/performance ratio and that you will definitely never sell and keep forever? I am excited. Hope it works!
|
|
|
Post by tonycamphd on Jan 25, 2016 19:06:35 GMT -6
So I was checking everything to the other VP28 with Litz I have (built by Joel Phillips) and I noticed I had R20 and R21 in backwards...which is phantom power apparently. I thought that might have been an issue, so I texted Jeff and before I got an answer back, I decided to heat them up and take them out...Then Jeff says that orientation shouldn't matter. DOH. Damn, that was a bad idea. I don't have a decent solder sucker thingy - just a squeeze suction thingy... The problem now is how in the hell to get the solder out an have a hole to put the resistors back in...I ended up kinda half-assedly soldering them back in...but hey, if the phantom doesn't work off the bat, that's fine. I think I screwed R20 up, so I'm having Jeff send me two more...then I'm gonna have a pro put them in (talking to you Shannon)... Everything looks pretty damn shiny to me...I'll post a pick in a sec. Then I'm gonna try it again. take a loan out, go to harbor freight and buy these, www.harborfreight.com/6-piece-pick-set-93514.htmlthen take the end of one of these picks and poke it into the filled up hole, now take your soldering iron and put it up against the pick and pad, once it heats up the pic and solder appropriately, the pick will drop down into the hole, now remove the iron and twist the pick side to side while the solder cools, it will not grab the pick as it cools, now pull the pick out of the hole to reveal a nice new through hole for your resistor leg. You're welcome 8)
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 25, 2016 19:15:10 GMT -6
Uhm, what i meant with the above: As far as i see, you will be able to fix quite a few things by yourself in future, which is a good thing. I guess you will be more self confident about such things the moment you fire the pre up and it works - without anyone else having layed his hand on this one....
|
|
|
Post by Johnkenn on Jan 25, 2016 19:25:56 GMT -6
|
|