BM/HRM w/Loop on Smaller Board--Tight Layout--Parasitics?

[David Root]

The pic is of my draft layout for a BM/HRM, based on Henry's schematic and a recent BM/HRM layout, with Normster's '97 ODS loop inserted. The HRM tonestack components are on the board, designed to lead out to pots on the front apron.

This makes for a fairly tight layout.

Other than I missed showing the 47 pF parasitic killer betweeen the PI plates, does anyone see any obvious layout problems in regard to parasitics?

Henry, O Master of Crammage, I hope you are around!

[Structo]

The only problem I can see that may cause a problem is the size of the orange drops (if you use them) may prove to be too big for the way you have it drawn.
You may want to pull out a couple of the right value and place them on the layout to see if they cause problems.
That is something I have run into before when drawing a layout.

[David Root]

Thanx Tom, I did that, with the caps and the RN65s and trimmers too. Everything fits.

It looks like it wouldn't, but remember where in most D-layouts there are several 0.1 uF caps, these are all .02 uF in the BM, except of course the 0.1 uF in the PI and in the loop section, where I left room.

The board is only 8 1/2 " long but it is a little wider than most at 2 7/8".

[Structo]

David I'm not sure if you have Viso but I made this mock up of a ODS board.
Probably more work than a pencil but it was fun to do.
This is a rough draft and not the final image.

[img:797:345]http://lh3.ggpht.com/_MHnI-B0pJ8k/TG13x ... ulated.jpg[/img]

[David Root]

No I don't. Is that the one everyone seems to use? It looks good. Where can I get it? Is it hard to learn how to use? I am all thumbs on software.

[ChrisM]

No I don't. Is that the one everyone seems to use? It looks good. Where can I get it? Is it hard to learn how to use? I am all thumbs on software.

Hey David,

I am working on a ODS type amp right now. It actually has more features than an ODS and is in a Princeton Reverb chassis (I'm trying to say it's tight!!!).

Anyways like you I was going to do a hand layout as I am not that good with computers. A friend recommended I give Visio a try as he said it will be way better than hand drawing in the long run. I had it installed on my laptop (if you don't have it, torrent it). I got Normsters parts library from the forum. All his Orange Drops, resistors, eyelets, etc are all to scale so it makes the layout work easy. No guessing on if parts will fit.

I got the entire board done in less than two days. Very easy to pick up and learn, quite intuitive. I know Henery uses Visio for his tight ass layouts as well.

Anyways give it a try I say.

[Structo]

Yeah, there is a bit of a learning curve, but if you persist you can make some nice layouts.
Having a nice library of parts like Norms is very handy too.

[David Root]

Chris, what is "torrent it"? No comprendo, "internet impaired".

Where is Normster's parts library, in the Dumble Files?

[boldaslove6789]

David,

Download Utorrent ( Its a program that lets you download bit torrents )

http://www.utorrent.com/downloads

And go to the Pirate Bay and download w/e you want

http://thepiratebay.org/

[David Root]

Thank you 6789. So I am in Pirate Bay with about 20 options on Visio downloads and no idea which one I need. Like I said, internet impaired.

[M Fowler]

The cheap visio 2003 is what I bought and use Barry witt and Normster's library.

[bluesfendermanblues]

David,

Download Utorrent ( Its a program that lets you download bit torrents )

http://www.utorrent.com/downloads

And go to the Pirate Bay and download w/e you want

http://thepiratebay.org/

Am I the only Boy Scout around here?? what you are suggesting is illegal. BTW piratebay has been banned in Scandinavia.

[ampdork]

Hey guys.

I got Visio Beta 10 (I think) for free.....at microsoft....

Not sure it is still available but dig around..

[talbany]

Iv'e tried the last 3 versions of Visio and the one I like best is 2007 version..If your just learning the program this is the one you want IMHO.. I still have all 3 and like this one the best.. Thought I would mention..

Hope this helps

Tony