What's the latest in Desoldering gadgets?

One of these.

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Jeff-1.0 
wa6fwi 
http://www.foxsmercantile.com

For through hole type stuff I love my DP-100. It pays to clean up the o-ring every now and then.

George H.

Well, you are certainly asking a lot of good questions!

I keep a number of things on the bench - and my wife, entirely unsolicited, purchased a fancy solder & rework station for me with hot air and such. Ye s, it is from China, but she even as she is aware of my resistance to thing s from China, she also a very practical individual, and spending many hundr eds vs. less than $80 does appeal. The hot air wand does a great job on boa rds, and the 'tunable' soldering iron can get hot enough for even 50-50 sol der to liquefy.

._SX342_.jpg I s an excellent tool for fine work.

g?v=1431988566 What my wife got me.

A bulb is fine in most cases, but manipulating it can be awkward.

Soldering braid is critical for board work.

Note that for years, I got away with a simple 38-watt pencil, a bulb, denta l picks and patience. But when I became more seriously involved with audio and boards, I got fancy.

As to pot and switch cleaner - there are several schools of thought on this - and Jeff is a purist. Rather than start a dead debate all over again, De Oxit in the quantities you will use (with care) is just fine.

Peter Wieck Melrose Park, PA

If you are going to recommend a desoldering pump I suggest you stick with the Solda-Pullet (made in USA). I have used the no-name knockoffs and they don't last a month in our shop, whereas I have three Solda-pullets that I bought over ten years ago that see daily duty and other than replacing the tip from time to time just last and last. We bought a fourth one recently and it too is running fine.

The knockoffs are just a waste of money.

De-Oxit is pretty good for what it does I hear.

We use Nu-trol from MG Chemicals and it gives long term repair to pots and contacts.

John :-#)#

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Didn't ElectroVoice sell a 30 inch speaker? It wasn't as big but you could actually buy one.

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Jim Mueller wrongname@nospam.com 

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Our church has a pipe organ that uses electronics for the lowest notes as they don't have room for the length required for a pure pipe bass. That sub would be perfect..

Sigh. That goes way back. I graduated to a pump type desoldering tool as soon as they were available: For $1.15/ea, get a pile of them.

Solder wick is useful for some things, but I avoid using it. Details if you want them later.

Next, I bought and rebuilt a Pace desoldering station: It worked well for me for many years. I now have several similar machines.

I then went to a hot air SMT desoldering station. Not this one, but this is what I would recommend: However, I would not use it on terminal strips or tube socket. It's made for PCB's only.

For recapping, I use just a soldering iron to heat both leads of the capacitor alternately and just rock the capacitor out. Or, I cut off the capacitor and extract the leads one at a time. That leaves the holes plugged with solder, which I remove with either the hand pump or the Pace desoldering station. I suggest something like this:

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Jeff Liebermann     jeffl@cruzio.com 
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Skype: JeffLiebermann     AE6KS    831-336-2558

I did not find that one on the web, but I did find THIS:

The Woofers are 80 inches each.... Handle 5000 watts per channel.

Heck, that would involve a power amp with around 200 6L6 or 807 tubes in Push-Pull Parallel-Parallel-Parallel-Parallel etc... For EACH channel...... (And an output transformer about 3 foot big, weighing close to the weight of a Harley motor cycle, and costing 10X the price for a brand new Harley).....

I do recall hearing about such a speaker.....

I recall in the early 70's when 15" was the biggest speaker sold, that some company came out with an 18". Of course I wanted a pair of them until I saw the price....

The red bulb ones don't work very well; the bulb is too small. The ones with a larger blue bulb are much better. But the main problem with bulb type solder suckers is cleaning them. You can shake a fair amount of the old solder out of the bulb but quite a bit remains. You have to be imaginative and patient to get it out.

--
Jim Mueller wrongname@nospam.com 

To get my real email address, replace wrongname with dadoheadman. 
Then replace nospam with fastmail.  Lastly, replace com with us.

I've never seen the blue ones, but I remember having a lot of problems with the tip getting clogged in the red one.

ElectroVoice did briefly offer a 30" woofer. It didn't sound very good and didn't last very long on the market.

Here's the backstory:

Paul Klipsch (father of the Klipschorn) had cut a deal with EV where EV provided 15" woofers with special characteristics to Paul to use in the 'Horns, and in exchange Klipsch licensed EV to produce both kits and ready-built versions of a modified K-Horn. (It was the EV "Georgian" in case you're interested).

The mods EV had made offended Klipsch, so he was already pissed at them (picky, he was), and then when the woofers they were sending started showing up with cracked magnets Paul cancelled the agreement and found another source for his woofers.

EV, no longer able to offer an enclosure with the bottom end provided by a horn woofer, tried to replace it with that 30" behemoth in a more "standard" enclosure. Didn't work out.

Later, EV tried a scaled-up version of the horn, using an 18" woofer (the "Patrician IV"). Paul told them that wouldn't sound right but they didn't listen. As usual, he was right.

Isaac

No, certainly not! You use the modulator from an old AM broadcast transmitter. I was at a Grateful Dead concert in 1969 and they wheeled out this THING on the stage with big glass globes, and when they lit up I realized they were TUBES (valves to the British)! Not sure of the type, but at least several thousand Watts. I borrowed a set of ear muffs and sat back for a show!

Jon

I was at several Grateful Dead concerts in the late 60's and afterwards. I never saw any such thing. Are you sure you were not "tripping"? That may have just been a common 6L6 tube in a guitar amp, and your hallucinations made it look really BIG.... :)

Who ever heard of wearing earmuffs at a Grateful Dead concert.....

And since you mentioned it. What the hell is wrong with them British? Valves are plumbing parts. Tubes are electronic parts!!!

Seriously, I have heard of using AM transmitter tubes for audio amps. I dont know what those tubes are numbered, or how much power they output, but I know that many AM radio stations have power output in the thousands of watts range. But to use that kind of tube would require custom output transformers that would likely mimic the pole transformers used to feed our homes....

And just for historic value, the original 1969 Woodstock concert ran Somewhere between 3500 watts to 12,000 watts, using Mcintosh mi350 monoblock tube amps for their PA system. The article below seems to conflict whether it was 3,500W or 12,000W. Either way, that PA system had to cover a very large area, and apparently it did the job.

These Mcintosh MC3500 power amps have EIGHT power output tubes

6LQ6/6JE6B. These amps had an output of 350W. (mono).

They went through various iterations, and sound people. SOmeone got hooked in at one point, maybe it was Bob Heil but maybe it was the soundman for Quicksilver Messenger Service (who was also a ham), there was s story of someone having an Electrovoice "Voice of the Theatre" or whatever it was adapting that. Owsley was involved, leading to the Wall of SOund, which almost as soon as they finally got it going right, they abandoned. They were using McIntosh amplifiers for a while, there's a story, maybe about Woodstock, where they blew them out and had to hurry to find replacements, finding a "close" dealership and getting them to open up on a Sunday or something.

Things were evolving, and bands like the Dead helped that developemnt. So they went to that Wall of SOund to adapt to the much bigger venues, then dropped it because it was too much trouble to move, but I thought the work helped other things to develop. So they may have been using just about anything at some point, including home built equipment.

If you paralleled enough tubes, the output impedance would go down, so no matching transformer for 8ohm speakers. I'm not sure if that was ever done with audio, but I have seen it done with radio amplifiers, a bunch of tubes in parallel so the output impedance is 50 ohms to match the coax.

Michael

This is a good article about the "Wall of Sound". It was (and probably still is) the greatest sound system ever built, but it nearly bankrupt the Dead, and moving all that equipmnt from show to show does seem very impractical. Those mcintosh MC3500 amps are still the best anps ever built. More powerful solid state amps have been built, but none can match that tube sound.

I dont doubt that there were fried amps, blown speakers and so on at those concerts. Everything was being run at Max power and much of this was still in development stages.

Paralleled tubes like you said, dont seem real practical for audio amps. Having that high DC voltage on the speaker leads seems very dangerous.

A pole pig would wave been useless, since they weren't designed to pass DC, and they aren't center tapped on the primary. On top of that, they would have a horrible frequency response, because they were designed to operate at 60Hz.

A 25KW, plate modulated AM transmitter would produce 12.5 KW of audio but you would have needed to a hundred amps of three phase 480VAC to power it. Something I doubt that was available on that farm, or from portable generators. You could move the modulator from a 5KW AM transmitter, but the modulation transformer weighed over a ton. We had to abandon one from a Gates transmitter that was bought from WQBQ for spate parts. Sadly, it was only a couple years old, and one of the premium replacements from Peter Dahl.

Those Mcintosh amps were not designed for that type of service.

The RCA TTU-1/TTU-25 UHF TV transmitters used 16 6146 tubes in parallel for a video amp with a response from DC to over five MHz. It was a 'Distributed Amplifier'.

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