What are my next tools?

[The Documentary Sound Guy]

I've been diving into a couple repair projects as a way of deepening my skills. A microphone and a crossover at the moment.
I've realized I need to up my soldering (and, especially desoldering) game if I'm going to start doing repairs of this type. Up to this point, my main experience has been soldering cables and connectors, with a few very basic component replacements here and there (e.g. fans or antennae).

The list of specialized tools and equipment that can help test and repair electronics seems quite long, and I'm looking for advice about how to step into this slowly and wisely.
Right now, I own a basic, cheap soldering iron & stand, a cheap jig for holding cables, a cheap multimeter, a couple decent wire strippers, tweezers, and a bunch of specialized tooling for audio connectors. All this has served me well so far.

My next step, I think, are the tools I need to remove and replace components, so desoldering wick, flux, a solder pump, some better alligator clips, maybe a better (or different) jig for holding things in place. I also think I should invest in a fume extractor, since I'm largely working in my home office.
Long-term, I assume I'll need an oscilloscope and some kind of signal generator.

What I'm wondering is what tools are missing from my list that I simply don't know that I need? I'm entirely self-taught, so I don't have the advantage of seeing how other people set up their workspaces. My main needs at the moment revolve around having what I need to test equipment (so I can more easily diagnose dead components), and replacing said components. I could also use suggestions around ergonomics (stands, clamps, etc.).

Please share insights about what's missing from my current equipment cupboard and my shopping list! My approach to buying tools is buy cheap ones first until I understand the drawbacks and why I would want to buy an expensive tool. Then I buy for life, and I'm willing to lay down money for it.

 

[cyrano]

Are you planning on repairing SMD boards?

 

[gyraf]

recently found this basic method of de-soldering complex stuff from plated-through boards: (try to ignore the annoying clickbaiting, soundtrack and lengthy talking) - it works well, and I'd wish I'd known this long ago.

For audio type repairs, I'd recommend

- some cheap oscilloscope, preferably analogue (more readable and cheaper second-hand). 20mhz is plenty, but you want sensitivity down to 5mV or better for chasing hum-
- audio oscillator (or isolating transformer if you want to use your phone/computer)
- a multi-component tester - the cheap far-eastern types are surprisingly usable, e.g. https://www.aliexpress.com/item/1005005237553083.html
- for hot-air type work, some of the cheap options are pretty alright too, e.g.: https://www.aliexpress.com/item/32879815225.html
- for power amp work, a variac and a dummy load (e.g. 8ohms total worth of power resistors)
- for live work, possibly a mains isolation transformer (or at the very least, a known-working ground-current-interruptor relay)

/Jakob E.

 

[ruffrecords]

recently found this basic method of de-soldering complex stuff from plated-through boards: (try to ignore the annoying clickbaiting, soundtrack and lengthy talking) - it works well, and I'd wish I'd known this long ago.

I have seen several videos showing a very similar technique. However, I am nt convinced the big fat soldering iron required is any improvement on a heat gun.

Cheers

Ian

 

[The Documentary Sound Guy]

Are you planning on repairing SMD boards?

I have no pressing need at this stage, so no, not yet.

audio oscillator (or isolating transformer if you want to use your phone/computer)

Can you say more about this? I was wondering if there was a good solution for using my computer as a test source.

Thanks for pointing out the multi-component tester. That looks handy. All your recommendations are great, though I think I'll leave the high power stuff for later (nearly everything I work on is battery operated, and I don't own any power amps)

 

[pucho812]

For repair you need
1.solder iron
2.desolder gun. The pump and wick can do more damage than good at times.
3. O-scope
4. Tone generator. A daw with an interface can cover this nicely.

While we can get into expensive tools like an audio precision and the ilk, for basic repairs you can go without.

 

[The Documentary Sound Guy]

4. Tone generator. A daw with an interface can cover this nicely.

Can this cover the whole range of outputs I might need? I'm working on a microphone capsule at the moment; I would have assumed I would need lower outputs (possibly with different impedance?) than a DAW interface would readily provide. And at the other end, I assume loudspeaker testing probably needs higher outputs...
On the other hand, I'm happy a regular output can work ... maybe I'll treat the capsule test as a special case.

 

[The Documentary Sound Guy]

Can this cover the whole range of outputs I might need? I'm working on a microphone capsule at the moment; I would have assumed I would need lower outputs (possibly with different impedance?) than a DAW interface would readily provide. And at the other end, I assume loudspeaker testing probably needs higher outputs...
On the other hand, I'm happy a regular output can work ... maybe I'll treat the capsule test as a special case.

Sorry, just realized my reply makes no sense. A capsule requires an audio signal generator, not an electronic one. It's the power supply I'm testing, and I need to feed it the equivalent output of a capsule to rule the capsule out. But that's OT for this thread.

 

[KLDVOX]

the tool i most need is a time machine so that i can correct my many mistakes

 

[The Documentary Sound Guy]

the tool i most need is a time machine so that i can correct my many mistakes

I'll build you one. Do you have a schematic for a flux capacitor?

 

[Philbo King]

A selection of surgical clamps (AKA hemostats, roachclips) is one of the most useful things I've ever picked up. The local military surplus store had a bunch of them for $2 each.

 

[KLDVOX]

i got a few clamps following a minor work related cut. the local A&E department were putting some stitches in my hand. i commented that the clamps looked like nice quality, the nurse said they all went in the bin after a single use. so i had the set of 3 given to me. i still have them 20 years later.

 

[Gold]

A cheap multimeter is fine for everything except AC Volts. Most multimeters are made to measure mains frequencies not audio frequencies. Multimeters with wide AC bandwidth can be expensive new. A multimeter is the most used piece of test equipment by far.

A new digital o scope could probably do double duty for ACV if it’s in the budget and you like them. I would suggest getting a Fluke 8050A from the bay for round about $50. That’s going to cover most needs. As long as it works it will be accurate. I’ve never seen one out of spec any significant amount.

Other than that getting hand tools you like is important. Everyone has different tastes when it comes to cutters, pliers and strippers. You’ll want a short and long needle nose pliers. A light duty straight cutter for trimming wires and a heavier duty diagonal cutters for cables and thicker wires. A good electronics vise like a Panavise.

For a desoldering tool I’d suggest a Hakko FR3. The cheap Chinese ones are practically single use IME. The FR301 is the lowest price one that’s worth getting IMO.

A bench power supply is a good thing to have as well.

 

[The Documentary Sound Guy]

Thank you, those are all excellent! And I like the idea of surgical clamps too.

 

[The Documentary Sound Guy]

For an Oscilloscope ... there seem to be lots of used ones around CAD$200 or so in my area. Everything from '60s-era tube scopes to a cheap touchscreen unit.
I have a feeling I'll start a holy war if I ask analogue vs. digital (I notice there's been one recommendation for each so far) ... but I want to ask about age. I don't think I want a '60s era unit ... I would worry about maintenance, accuracy, and old components going. But there's a decent number of '80s era equipment around. Should I be worried about age in that era? I'd be pretty worried about the capacitors.
I've found a Tektronix TDS320 with specs that I like, but I have no idea how much age would affect that. I don't love the idea of a 320 line monitor & slow refresh rates, but for a functional first scope I think it's decent.
There's a much more recent Atten ADS1102CAL+ listed as well for a similar price. I've never heard of that brand, and I know Tektronix is well trusted. But I'd imagine a newer scope would be more reliable. Just not sure I should trust an unknown brand.

 

[Gold]

There are advantages and disadvantages to both analog and digital scopes. An analog scope will be cheap and if you pick the right one will be very low noise. A Tek 465 is a classic. This allows looking at low level signals that is not possible on cheaper digital scopes. The trace on an analog scope can tell you things by the way it wiggles that a digital scope can miss. None of these subtleties are probably much use to you unless you use things like tape machines.

A digital scope can do a bunch more stuff. It will give you an ACV readout. It will probably have an FFT mode which lets you look at the audio frequency spectrum by amplitude. A fancy RTA. But a cheap one won’t tell you what’s going on at the noise floor.

 

[pucho812]

Sorry, just realized my reply makes no sense. A capsule requires an audio signal generator, not an electronic one. It's the power supply I'm testing, and I need to feed it the equivalent output of a capsule to rule the capsule out. But that's OT for this thread.

For testing the psu, can do that with a multi meter. Easy enough to hook up the mic and probe voltages.

 

[The Documentary Sound Guy]

I did spot a Tek 465B. I counted it out because it's so old...
But good to know about the noise floor. Don't have any tape machines, but I'd imagine servicing microphones would push the envelope into the noise floor.
Do you think a 465B would be reliable enough? I read lots about how they needed a lot of upkeep these days.

 

[The Documentary Sound Guy]

For testing the psu, can do that with a multi meter. Easy enough to hook up the mic and probe voltages.

Aye ... I'm following Sennheiser's repair guide which gives directions to bring it back into spec. Those directions use a signal generator soldered in place of the mic capsule.

 

[pucho812]

Aye ... I'm following Sennheiser's repair guide which gives directions to bring it back into spec. Those directions use a signal generator soldered in place of the mic capsule.

What mic?