Avoiding soldering by using double-sided conductive tape + shrink tubes

Factual Questions
61

Not only do I have carpet, but it is the filthiest carpet!

I found one screw just now that was embedded such that the head was at normal angle/perpendicular to the surface.

Not deep shag carpeting, but…yeah…it’s not that good for “treasure” hunting!

More concerned about the correct length hex screws for mounting the top panel…I have two out of four.

It’s not really necessary, in my experience, for all the screws to be there for stability’s sake, but tends to be the kind of thing people notice.

Well, I can probably buy some replacements that will work perfectly…but I’m enjoying procrastinating the final countdown…which tune this synth can probably nail perfectly! For all I know it might have been used on Europe’s recording.

Seems not, but the Ensoniq can definitely do that Roland sound.

62

I may have missed this earlier; potting compound could be used to provide mechanical strength and resistance to rough handling for your solder joints. Polyurethane or ordinary silicone sealants could be used.

63

Thanks! I may look into that for the joins to the battery posts on the PCB…but my time spent on this project is well exhausted.

The joins to the coin battery holder seem more than adequately strong (and, yes, I’ll tack it down inside the chassis probably with some hot glue or something…well, no probably about it…that’s the one area where things will be “flapping in the breeze” especially being delivered by UPS.

This lady who bought the instrument though is getting to be a nudge (the payment is held in escrow by Reverb until it is actually in her possession and she’s satisfied). I’ve kept her in very close details about the issues and my progress, and even offered to expedite the shipping at my expense. To which offer she said, “No, do not expedite shipping! Just send it as you were going to.” Not one day later she’s again asking for an update.

Which is fair, but make up your mind, ma’am! She’s insisted again and again, “No, speed of delivery is not as important as that the instrument be 100%.” And recently, “No, do not bother expediting shipping.” I understand she’s frustrated, or at least I would be, but it seems she wants it both ways.

I’ve already told her the situation, from my end, and the specific steps I’m taking to minimize any possible damage to the board done in transit.

Just for that, I’m not testing the floppy drive! I’m not sure what shoving some ancient non-double-sided non-double-density disk in there is going to prove anyway. The drive has never been used since it was brand new. It either works or it doesn’t, and I don’t much care either way.

Anyway, tonight’s the night I’ll clean the kind of crappy chisel tip the Weller 60W came with, as well as the battery posts, make those two simple joins, put a protective little sheath of heat shrink tubing over the middle portion of the wires, cram in whatever CR2032 I can find around the house, then fiddle with pushing the various connectors back onto the mobo and screw down the internal metal housing.

Flip the lid down, power up, and try to make some noise.

If it works, then I can buy a high quality lithium CR2032, put that in there, screw down (well…three of the four hex screws for the main assembly), give her some spit and polish, (a really good, thorough cleaning…the dust in my place is quite…abundant), make a short video of running the diagnostic self tests described in the Service Manual (because I can’t really remember how to fully operate this synth), and head to UPS to have them “Pack and Ship.”

So she had to wait ten days for me to prepare the instrument! I’m not some music shop, just some dude with a synth she wants, and I sold it to her at a hundred less than asking price, plus a deep discount on shipping.

And she could have cancelled the order at any time and got all her money back immediately.

Sorry about that minor venting episode…that’s just the reasoning I’ve come to that is empowering me to finish the job, stop lollygagging in analysis paralysis, and get 'er done.

64

https://www.youtube.com/watch?v=9jK-NcRmVcw

65

Whew.

Goddamned, it’s like defusing a bomb or some shit.

I just went sloppy and bent as much of the wire around the posts as I could…even my smallest binder clips couldn’t get much purchase and it turns out a third hand would have been very helpful.

Meh. Joins seem solid. After I finish having a heart attack or two, I’ll fire her up with mains power.

And those apparent burn marks on the big ribbon cable? It was like that when I found it. Probably other kids. Meh, it’s fine. Don’t worry about it. A little Bondo and some mascara, and it’s like it didn’t run into a door or nothing.

Oh SHIT!!! Blue was negative/ground! Fuck!

Uh…that’s a problem!

Can be easily fixed, though!

Well, it can be!

OH, yeah, I’ll just flip the wires at the battery holder. I’m not going into that Hanoi pit of Hell again!

Whew!

And note how I did not forget to put a little piece of shrink tube over the midriff of this bit of cable! I rule!

Lesson learned, though: good cleaning with isopropyl and a Q-tip makes nice shiny giant blobs of solder! Hey, at least it’s shiny!

No, I don’t have a suck bulb or desoldering tape, but I have a bunch of spare battery holders, and there’s enough extra length on the wire/leads. Trust me, it’s fine. Here, hold my beer!

66

So blue is the new white, and white is the new blue, and blue is the old black, and white is the new red.

Wait. Well, you know what I mean.

Got it.

Man with the plan.

You’re welcome, by the way, for the demonstration of skill, foresight, cunning and mastery.

I meant to do that.

67

The eagle has almost landed!

She still gives a low voltage warning, but that may be because I put some CR2016 in temporarily that came with some cheap gadget just because that’s what I could find easily at home.

BTW, that metal plate is not that fun to fidget in there among all the cables and that big ribbon cable.

But, she makes noise, and the polyphonic aftertouch works fine. Needs a good cleaning with some alcohol swabs and such, just for hygienic purposes, but to my great surprise, probably won’t even need to clean the audio contacts with DeOxit. No crackles, no sputters, from either of the L/MONO or R 1/4" output jacks. I’ll test the MIDI as well.

But I’ll go out and splurge for a name brand CR2032 and batten down the hatches tomorrow.

If she still says “low voltage” on POST, I don’t know exactly how to remedy that…the joins I made are solid, but it’s possible there’s some kind of improper contact that could lead to a short. It’s not too late to at least insulate the joints to rule that out.

68

BTW, you can make your own new soldering iron tip from copper wire.

69

That white wire soldering job is embarrassing. Needs more practice on disposable stuff.

70

True!

But no one is ever going to see it!

Maybe some technician in the future, but they’ll just say, “Well, some kid needs to practice more or else find a new trade! What a maroon!”

Meh, the wire isn’t falling off anytime soon, so it’s putting the lotion in the basket…it’ll be fine.

Yes, I may have to redo that bit if a known-good battery continues to give improper readings to the board, but I’m fairly sure what’s underneath the solder has proper contact.

71

This thread is giving me hives because I am also a piss-poor solderer with a project to do for someone else (a gift). I hope you figure out the voltage problem.

72

Well, dammit.

Ran up to the grocery store, bought a new CR2032…“Warning Battery Voltage is Low.”

I’m just going to have to e-mail the seller and say it can’t be done.

She has a lead on another Ensoniq SQ-80 for cheaper, but with only dodgy assurances from the other seller that “it works.”

So, my days as a “seller” for anything but non-local pickup are over…what a nightmare.

At least she knows now that I’ve failed, she’ll get a full refund from Reverb, and the machine won’t have to be shipped cross-country &c.

73

Did you test this this circuit before soldering it?

74

Test across the battery posts with mains power on?

No.

Probably should have, is what I’m guessing?

75

Why are you in this business?

76

What “business”?

I’m not in any “business” except playing music.

77

Why are you doing this? What does “So, my days as a “seller” for anything but non-local pickup are over” mean?

78

It means I don’t want to sell or trade instruments online. Don’t want to deal with shipping, and would rather have some other musician come see for themselves if they want to buy or trade an amp or a keyboard or a guitar or something.

In the case of this synth, any number of local shops could do the rudimentary soldering for probably $50 at the very maximum, or I could have a pal do it for free, or a few hours table time at a local pool hall, or whatever, and I could put it on consignment at a local music store.

I don’t know if you’re aware, but there’s a long history of musicians buying/selling/trading all kinds of gear, without entering “business” as a professional merchant, nor as a finder of rare antiquities.

I thought I could fix this, told the musician buyer the exact details, day by day, and admitted that I failed. She appreciated the honesty, and now she can gamble on something else over the mail.

She lost a week’s time, which I regret, thanks to my hubris, but she didn’t lose any money, nor did she have to deal with returning the instrument in the event that it were damaged or lost in transit.

Or, she might very well decide to buy the synth from me at a reduced price, if she doesn’t find anything better, given how easy even a drunken toddler should be able to fix this.

I don’t find it very complicated.

79

Sorry, was not aware of that, I’m highly non-musical. So you were just helping out your fellow enthusiasts which is admirable. I think you just need to practice soldering on something that doesn’t count until you feel comfortable doing it. I suppose some people got it right the first time but probably most like me left some horrible looking solder blobs and cold joints on circuits boards before we got better at it.

80

Well, it wasn’t altogether altruistic: tit for tat, through the intermediary of cash.

I do think that we are both serious musicians with an awareness of the value of certain instruments beyond mere monetary value, and that we communicated candidly about needs, desiderata, and shared information about the role this particularly instrument would play in various home studios, in both our cases, helped avoid any bad feelings.

Well, then I think we agree!

What I need now is some desoldering ribbon or a decent solder sucker and start from scratch.

Clean off the mess I made, and test continuity.

Hell, for practice’s sake, I can go through the entire service manual for fun, checking readings with the multimeter. That particular part is actually fun for me, rather than soldering a bunch of crap like a robot, except less good. Maybe I can convince a nephew to learn to solder and make him do all that tedious crap.

Or, after cleaning up my gunk and goo, just have a tech make it right. Possibly reinstalling a fresh Br-2/3. Try to sell/trade it this time as “mint” (or whatever) with recent service. The instrument itself is impeccable, never been gigged, the classic “old lady only played once at church.” The exterior is flawless, the keyboard mechanism has zero faults.

No original box or printed manual are its only faults that may make it not “mint.” Well, that and the original battery dying a natural death after decades of service. The 3.5" floppy drive doesn’t appear to have any problems, but IMHO only a crazy person would use a 36 or 37 year old drive with disks that are likely nearly as old, at least in the 2-sided 2-density recommended (demanded, actually, since the OS formatting system does no error checking or flagging of bad sectors…it’s all or nothing), especially since drop-in units that accept USB/flash drives are cheap and readily available. And presumably can hold more than…what were those? A few MBs. Not that the information stored is particularly voluminous.

Or I can just fix it back up myself and keep it…except while I know the basics of how to build sounds on a traditional synthesizer, it’s not something I ever use, as a sound. I only play pianos (including vintage electric pianos) and the Hammond organ, in addition to a bit of guitar and bass guitar.