PCB design again/ Another layout posted

[Bob-I]

I'm still struggling with PCB design. My goal is a single PCB version of the D-Lite but with relay switching on the PAB and channels. I used the expresspcb free software expresspcb.com . Since this is difficult at best to export, I'll post the file. If you want to take a look you'll need to download the software.

http://www.patmedia.net/bob-ingram/DClo ... e_ODS4.pcb

The off board pots and tube sockets will of course be removed for production, but I placed them there for checking the wiring. Also I've placed the tubes on opposite sides of the board, ALA Slo, preamp tubes near the pots, power tubes at the rear.

Don't worry about offending my PCB layout abilities, I have none so you can't offend me.

[odourboy]

You might get more 'takers' if you print the output of the pcb software to PDF format and post that. Then everyone can look at it without having to install that software. (In an effort to keep things tidy, took it off my PC and I'm loath to re-install it again!!)

[mdroberts1243]

You might get more 'takers' if you print the output of the pcb software to PDF format and post that. Then everyone can look at it without having to install that software. (In an effort to keep things tidy, took it off my PC and I'm loath to re-install it again!!)

Not everybody has the ability to create PDF... so I've taken the liberty of posting this one.

[odourboy]

Not everybody has the ability to create PDF... so I've taken the liberty of posting this one.

Get the ability here... free:

http://www.cutepdf.com/Products/CutePDF/writer.asp

[ampdoc1]

Bob-I,

I'm printing this out and will take a look. I designed a Dumble schematic a couple of years ago, but I was going to put the preamp sockets on the PCB. I also added in the HRM, PAB, and the Dumblator. I think the design was pretty good, but it was gonna' be ~$400 for the board.
I'll check in tomorrow.

ampdoc

[Bob-I]

You might get more 'takers' if you print the output of the pcb software to PDF format and post that. Then everyone can look at it without having to install that software. (In an effort to keep things tidy, took it off my PC and I'm loath to re-install it again!!)

Not everybody has the ability to create PDF... so I've taken the liberty of posting this one.

Thanks my friend. I did not have that ability so this is a huge help.

[Bob-I]

Bob-I,

I'm printing this out and will take a look. I designed a Dumble schematic a couple of years ago, but I was going to put the preamp sockets on the PCB. I also added in the HRM, PAB, and the Dumblator. I think the design was pretty good, but it was gonna' be ~$400 for the board.
I'll check in tomorrow.

ampdoc

I thought about mounting the tube sockets on the board too but the cost factor was a big issue. This board will cost about $60 each in quantities over 6.

[Bob-I]

ampdoc pointed out a few mistakes which I corrected. Turns out I had a pot designation wrong so middle and bass were reversed. Also, this is not exactly a D-Lite schematic, it's an HRM schematic that I've used before successfully, I only called it a D-Lite because that seems to be the de-facto standard name around here lately.

[heisthl]

I thought about mounting the tube sockets on the board too but the cost factor was a big issue. This board will cost about $60 each in quantities over 6.

I never liked heater paths on a PCB but the space savings with putting components around the tubes is a benefit. The best of both worlds might be to chassis mount the sockets and run the heater wiring and make the PCB have 1" holes where the tubes are mounted with a ring of solder points around each. Mount the board on standoffs enabling short lead lengths to the tubes. Some might say its harder to service but my feeling is if you build it right you should be able to replace anything without removing the board.

[ampdoc1]

Heisthl has a good point. All the Rivera amps I have seen are made like this. He has the holes/pads close enough to just bend the tube socket terminals over and solder them to the board. Mount the sockets with tap screws from the top of the chassis, and the whole thing can be pivoted out if required. Rivera also uses PCB connectors for all the other connections, so the boards can be completely removed. I don't know that I'd recommend this as these can get noisy, loose.

ampdoc

[mdroberts1243]

ampdoc pointed out a few mistakes which I corrected. Turns out I had a pot designation wrong so middle and bass were reversed. Also, this is not exactly a D-Lite schematic, it's an HRM schematic that I've used before successfully, I only called it a D-Lite because that seems to be the de-facto standard name around here lately.

Just a couple of nits... the pads to ground trace for C25, C26 and Ground don't seem to connect to the ground copper.

I'm an expressPCB newbie, but I like the way you use the external components from the PCB... is there a way to link them to the schematic?

[Bob-I]

Just a couple of nits... the pads to ground trace for C25, C26 and Ground don't seem to connect to the ground copper.

Yep, I missed that. I too am an expressPCB newbie. You have to right click and make the bottom layer pad shape a "thermal pad to filled pane".

I'm an expressPCB newbie, but I like the way you use the external components from the PCB... is there a way to link them to the schematic?

Yes you can. Just draw them in your schematic and link the schematic to the PCB. When you use "Highlight net connections" it will highlight all of them. My plan is to remove all the off board components and traces before ordering.

[mlp-mx6]

Is it your intention to have tube connections and pot connections from the same edge of the board? Don't these generally go to opposing edges of the board? Will this create long pot wire runs?

[mdroberts1243]

Have you considered having the AC in and DC rectification/filtering for the relay supply on the same end as the HT supply? Then you can use the 5V winding on the transformer (if it has one) like the D'Lite Relays version without a long run of AC twisted pair to the other side of the amp.

[Bob-I]

Is it your intention to have tube connections and pot connections from the same edge of the board? Don't these generally go to opposing edges of the board? Will this create long pot wire runs?

The intention was to have the pots and preamp tubes on the same side of the board as drawn. Soldano does this and it makes for a clean build. My reasoning was that the power lines are across one side of the board, signal on the other.

I'm not sure this is best and it won't work for any of the chassis made by folks here. Maybe what I'll do is draw up one in a more standard tubes all in a row layout.