To etch or not to etch-that is the question?

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My first DIY is fast approaching. I would like a little input from the community about a MAJOR issue I'm confronted with. Should I etch boards for this? Should I bread board it, and go point to point? Should I wire wrap it?

1)-Etching- While I can do this, is the time worth the investment? It's been YEARS since I've etched anything(about 10 years, college was a long time ago). Will it sound better than a non etched amplifier? Any thoughts.
2)-Bread board and point to point-This I can ALSO do. While this may be the easiest to do, are there any major drawbacks to it? Will sound quality suffer from this method versus an etched board?
3)-Wire wrap-Again, I can do this, but it's a MAJOR pain in the rump(and I don't have the tools for it).

Any thoughts, inputs, suggestions welcome/needed. Should also mention a bit about this thing. Rails are about 70v+-, it's a BJT amp, not a FET. AND, for the most part, each channel is commercially available in a stereo amplifier. Each amp has a pair of devices per rail per channel. I'm planning on using BOTH set of devices paralleled per channel(total of 4 pairs per channel) for a higher operating current. It's a totally discrete amplifier, with a VERY straight forward A/B topology. I don't actually plan to double the rated power(150WPC) of this amp, MAYBE(and this is pushing it) 225 to 250 WPC, with a low THD(.09 or lower). It will be driving a pair of Monitor 12B Polk's that have had the treatment(upgraded XO's, tweets, ect.....).
 
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do you want to be a etching hobbyist or build amps?

for through hole discrete components perfboard or clearance hole gnd plane with point-to-point can be electrically better than single layer pcb - you should look closely at a number of such builds to see the possibilities

add a little work with Kapton and copper tape, xacto knife to peel up gnd plane in some areas and you can even compete with 4-layer layout quality

if you were going for more than 2 channels I would get 2 layer, plated through hole pcb made from one of the many cheap pcb houses
I think the mess, chemical disposal issues and time involved to get poor quality homebrew pcb isn't competitive with today's pro prices
 
I agree with jcx. I think you'd be a bit crazy to do the whole homebrew etching process. I use this place:
ExpressPCB
Free software, and 3 boards for $50.
There are a few others including PCBexpress which has slightly fancier software. If you do a search you'll find others. The boards are delivered in just a few days after you push send from your computer! No mess and and high quality.

If your circuit is simple enough, just buy some perf and solder point to point.
Wiring wrapping can be fine, but not for anything high voltage or high current like amps.
 
If you like your results quick, there's nothing to beat making the boards yourself. Etch or isolation rout, I've used both. The problem with etching, you have to drill manually. The problem with routing, sometimes the isolation fails. The problem with either, no plated-through holes, so all your connecting tracks have to be on the side opposite the component, and you have to create vias by hand.

It's incorrect to suggest that a homemade PCB will be poor quality.

PCB has a big advantage over wire wrap and perfboard. If your schematic is right and you stuff the board right the connections will be right i.e. it will work.

Perfboard is hygroscopic and is only really any good for short-lived prototypes and low frequencies. Plus you have to think while you're constructing on it. I'd rather make a PCB even for something simple, and because it's easy, I do.

You will be more productive and more creative if you do not depend on a PCB manufacturer and postal turnaround. It's like the difference between old-time film photography and digital. The quicker and easier you get the feedback, the more you do and the more you learn. It's easier to commit to making a board yourself than it is to commit to spending $50, and you still have the option to do that once you've proved the design.

w
 
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I think it is a matter of taste. Or you etch your own boards (like I do!), or order from those express services. Doing this at home is much cheaper, but takes time, and you MUST love that! For me, drilling is the toughest part of the whole process. Although I use a manual punching tool, larger holes ask for appropriate drill.
Cheers,
Max.
 
The "Staples" brand paper that the article mentions does not seem to be available. Does anyone have a thought as to a viable substitute?

Forget about glossy photo paper. I've used many different kinds, even the staples stuff, and it's a pain to remove all the paper from the PCB once it's transfered.

I've switched to "Glossy Presentation Paper" and will never go back to photo paper. The stuff I bought was HP brand (Q2546A).

You can see my results with it here.....

http://www.diyaudio.com/forums/equipment-tools/162498-laminator-toner-transfer-2.html#post2150475
 
2)-Bread board and point to point-This I can ALSO do. While this may be the easiest to do, are there any major drawbacks to it? Will sound quality suffer from this method versus an etched board?
3)-Wire wrap-Again, I can do this, but it's a MAJOR pain in the rump(and I don't have the tools for it).

Forget wirewrap. It works fine for 3V logic signal swings, with gold pins, but my H182 organ has some on the preamp, and even with 40 mv Hammond signals, some of the pins had to be soldered by dealer service. Music goes too soft and low voltage for wirewrap. There should be tons of wirewrap surplus on the market now, but I think it all went immediately to the gold recycler. I used to do it professionally, liked doing it, but logic only.
I don't know the world, but newark is charging about $20 for perfboard drilled, and triodeelectronics is charging $10 for a turret board with about 40 turrets. The turrets are so far apart, it is more suitable for tube circuits, not for signal transistors. I've got 6 transistors and about 20 other things crammed on a 1.5"x2.5" board that fits in my ST120 amp where the new smaller bypass caps left a little room. At my income level I found some surplus HV circuit breaker boards at a sale of stamping presses. Have been stripping the big brass screws and drilling them myself, at 4 pockets full of boards for $1. I realize now, if I didn't luck into that, I could buy lexan sheet at the lumber supply and cut it with my sabre saw and drill. Neither is hydroscopic. Much cheaper than pro perfboard, and I haven't broken a #33 drill yet. (I sharpen them myself with a 7" grinder). Some teflon or kynar wire to resist inadvertant burns, I've done a couple of projects. Fatter wire for power circuits, I've been salvaging from dead PC power supplies. Triodeelectronics has some fabric 22 solid wire in 10 colors, resists burns better than pvc and he sells a twist of each color for $2. I'm making standoffs to hold the board off the chassis or heat sink by cutting up 1/4 nylon air tubing and using #6 screws and nuts. Been salvaging heat sinks from dead factory VFDrives.
My computer is too weird to run windows compatible layout software. Anybody got any linix compatable routing software,pipe up. I would think about it if I want to sell something.
Been looking at little microamp pcb's from tonepad for little 1 dual op amp circuits. Not everything can be done with TO92's. Those little dip pins are awfully close together for soldering, and easy to overheat. These would be installed on a bigger perfboard for the rest of the circuit.
 
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I didn't even think about using an etch house(which is kind of ironic since I live about 4 blocks from one-Lectra Circuit). I might go that route then. This is a "prototype", but it's for my personal use. I have NO plans of trying to mass produce this thing. It's just a hobby, and I need a little more umph to make my Polks dance a little better. I might post the modified scat(don't know if I can get into trouble for that or not-I'm thinking yes). Posting pictures is a most definite, otherwise it never happened. Now all I need to do is acquire the other amplifier, and a few other parts. Hopefully by the first of the year it'll be operational. Thanks for the responses.
 
Well,
depending on the size of the circuit I see two options.

When I do small circuits, I use an unetched as a base. I then draw all connections in the air. I usually works fairly well.

On the other side, if you have spent so much time designing your new circuit, I think you could afford the cost of a well manufactured board.

Some friends of mine are really good at etching their own PCBs, but I think it takes a while to get good at it.
 
You all need robo drill, LOL:
 

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Forget about glossy photo paper. I've used many different kinds, even the staples stuff, and it's a pain to remove all the paper from the PCB once it's transfered.

I've switched to "Glossy Presentation Paper" and will never go back to photo paper. The stuff I bought was HP brand (Q2546A).

You can see my results with it here.....

http://www.diyaudio.com/forums/equipment-tools/162498-laminator-toner-transfer-2.html#post2150475

That is pretty impressive but I do like double sided and 4 layer boards. I've never tried 4 layers for audio but it's excellent for HD video (30 MHz - audio on steroids). Is it possible to do double sided plate throughs that way?

 
Bernie Hutchins, electronic music expert/wizard and electronics instructor taught me years ago, around 1981, how to do "surface mount" because he didn't like having to drill holes in his boards. You just take DIP components and bend the leads out. Wish I had a picture of our project that was built this way.
http://electronotes.netfirms.com/

Some of his free online issues of Electronotes - Bernie is able to explain the most complex topics with amazing clarity. Variations on some of these publications were used as lab notes for graduate courses:
NEW ISSUES AND SPECIAL REQUESTS
 
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