Viva Analog 360+ Question

[Joe Viau]

First, thanks to J. C. Maillet and Moosapotamus for all of their great work on the Acoustic 360+.  J. C. did a great job bringing this to life, and Moosapotamus' pictures and sound samples are excellent.

I was looking at the PC board for the project, on the Viva Analog web site.  I saw one picture, and noted that the componenets were soldered on the foil side of the board.  In looking at Moosapotamus' site for this project, the pictures show all componenets soldered on the blank side of the board, except for the ICs, which are soldered on the foil side.  I'm a bit confused.

Could I not take the board, invert the image horizontally, create a new board and load all the components from the blank side of the board? Of course, this might affect component orientation in some instances, although I din't see any polarized caps that were oriented horizontally.  I would prefer to stuff the board from the blank side.  By the way, I'm using Moosapotamus' DPDT layout.

Thanks in advance,
Joe

[Joe Viau]

By the way, does anyone know where to get a good quality 1 unit 19" rack mount enclosure for this? I've Googled and didn't find anything (yet).
Thanks.

[Pushtone]

Hi Joe,

A link to the files would get you more replies.

AFA a 1RU chassis...

Middle Atlantic makes a very nice one but it is expensive. $60.00 here in Canada.

There are these chinese imports that are almost half that price.
The down side is the front panel is made with two pieces of steel with a small gap in between.
That makes it a little harder to work with. Some parts might not stick out far enough to get a nut on the other side.
I buy the imports at a little shop here in vancouver called Lee's Electronics on Main St.

I don't see any enclosures on their website.
http://www.leeselectronic.com/catalog/index.php

Perhaps give them a call.

A bought a small 1/2 rack of the no-name import brand that I used for an amp.
Here are some pics of the 1/2 rack chassis. pic1, pic2

Good luck with the 360+

[Joe Viau]

Thanks for the reply, Pushtone.  I guess that links would help, wouldn't they?  By the way, the pictures you linked look pretty close to what I believe I can use.

On J. C.'s site: http://www.lynx.bc.ca/~jc/pedals360.html

Use your browser to scan for "My Hand Drawn Schematic".  Go down a little further, and you'll see the pictire of the PC board with all the components on the foil side.  A little lower, there is the link http://www.lynx.bc.ca/~jc/charlieDpdt.gif which I am using for the layout.  If you look at the NE5532 op amps in the layout, Pin 4 is tied to ground and Pin 8 is tied to Vcc if the chip is on the foil side of the board.  And yet, when you go to Charlie's site, http://www.moosapotamus.net/THINGS/360+.htm you'll see in the second and third photos that most of the components are on the blank side of the board while the op amps are on the foil side.  So, my thinking is, why not just flip the board left to right, correct the orientation of the op amps so that they can be mounted on the blank side of the board, and respect the new orientation in regards to transistors and polarized capacitors?

I guess that what I'm  doing is to treat the board like a two-layer board with a top layer and no bottom layer, and I would like to move the top layer to the bottom layer, like I'm looking through the top of the board.  My spatial manipulation isn't that good, but if I flip the board, create a transfer, and iron it on, I'm trying to get that pattern to transfer properly to the bottom of the board.

UPDATE: In going back to an older version of the web page, I found the following note:

"NOTE** ALL COMPONENTS ARE SOLDERED ON THE TRACE SIDE _ I ASKED THE MANUFACTURER TO NOT PUT ANY HOLES
IN THE BOARD SO THAT IT COULD BE MADE TO LIE AGAINST A METAL PLATE - BUT THEY THOUGHT THEY KNEW BETTER ...
DON"T USE THE HOLES LIKE YOU NORMALLY WOULD WITH THIS PCB TRACING ...

I guess that answers the question, but I find it much easer to solder with the components on the blank side.

[Eb7+9]

Joe, forget that original layout ...
try this one which was sent to me some time ago - you need expressPCB ...
highlite traces only and screenPrint to a photo-editig tool, etc ... to a laser printer, etc ...

http://www.lynx.bc.ca/~jc/360+lyt.pcb

I haven't checked it for mistakes - let us know ...
god luck

[Mark Hammer]

You don't really need to get a "rackmount chassis".  As long as the number of controls, and the intended knob and pot size works out, you can simply use a standard 1U/1.75" blank rack panel, and attach a low profile aluminum box to it.

For example, Hammond makes the 1444-15 ( http://www.hammondmfg.com/dwg21.htm ), which is 10" wide, 6" deep (front to back), and 1" high.  Assuming you use 16mm Alpha pots, and appropriately-sized jacks, and don't use chicken-head control knobs (which require wide spacing) you're good to go.  The chassis requires a matching cover plate.

The two caveats for this arrangement are that: a) installing an internal power supply may be tricky, given the low profile of the chassis (though you can always install a jack for a wallwart), and b) aluminum rack panels tend to thick-ish, so if the chassis is going to be connected to the rack panel via the pots attached from the outside, you'll likely need to counter-sink the holes you drill so that enough thread from the pot shaft sticks through the front of the rack panel to screw the nuts on.  You'll end up with slightly recessed nuts (sounds like the aftermath of a football game! ), but the perk is that the knobs will be more flush with the panel surface, which tends to be nicer-looking.

The panel and box should cost you less than the $60 Dave mentioned.  Again, it is a solution that works nicely if a number of other factors are aligned.

[Joe Viau]

J.C.:
I appreciate your posting the PC layout.  I will walk through it over the next few days to see how well it matches your hand-drawn schematic.  If I see problems, I'd be happy to relate what they are.  I'm looking forward to doing this because this will be the front-end to a nmos 400W bass amp that I'm DIYing for my son.  It will be great fun to bring this to life! I do have ExpressPCB and have printed PCB layouts in the manner that you mention.

Mark:
Thanks for the explanation regarding the front panel and the Hammond box.  That should work nicely.  I suppose I could use any suitable box, but the rack stuff looks nice when done well and painted carefully.