[amb]

Oh and four layer boards? I hope you have a pretty deep pocket

. They will be spendy in small quantities.

 

[dgardner]

I don't mind the cost of the four layer board if it provide real benefits. I've been building up 6 dynahi boards (2 layer) and working on the prototype dynahi power supply (2 layer) lately.

BUT... I'm getting back on *this* project on Monday. I'm thinking that a two layer board with a topside ground plane and some bottomside power rail fills might do the trick and then the price stay under $200 for a 20 piece proto run. Otherwise, four layer boards from North American suppliers seem to fetch a minimum of $400 for a 20 piece order.

I think there's lots of people who will want to build this board. The dynahi is too big, hot, and expensive for a lot of folks. Hope to post a few updates later next week...

 

[Garbz]

Indeed there's a lot of people who have built this

 

[jogor]

hi, been searching for a resonably priced dynalo/dynamid pcb. dgardner, thank you for initiating and sharing. i will definitely join in the group buy if my wallet permits. by the way, is MPS8099/MPS8599 a much better choice compared to 2SA1015/2SC1815 specs/performance wise (to anyone who tried them)? i could not find mps8x99 specs sheet

and vendor as well, thanks again.

 

[amb]

Quote:

Originally Posted by jogor hi, been searching for a resonably priced dynalo/dynamid pcb. dgardner, thank you for initiating and sharing. i will definitely join in the group buy if my wallet permits. by the way, is MPS8099/MPS8599 a much better choice compared to 2SA1015/2SC1815 specs/performance wise (to anyone who tried them)? i could not find mps8x99 specs sheet and vendor as well, thanks again.

The MPS8099/8599 were Motorola, but is now On Semiconductor:
http://www.onsemi.com/site/products/...PS8099,00.html
http://www.onsemi.com/site/products/...PS8599,00.html

These are good transistors and can be used in lieu of the 2SC1815/2SA1015. Note the pin-outs are different! Here are some basic comparisons:

2SC1815/2SA1015:
Vce 50V, Ic 150mA, Pd 400mW, hfe 100 typ, Ft 100MHz

MP8099/8599:
Vce 80V, Ic 500mA, Pd 625mW, hfe 100 min, 300 max, Ft 150Mhz

One advantage of the 2SC1815/2SA1015 is that its hfe is very linear over a wide Ic range. This makes them easier to match.

The MPS8099/8599 are available from Digikey. The 2SC1815/2SA1015 are available from BD Enterprises.

 

[dgardner]

Quote:

Originally Posted by amb The MPS8099/8599 are available from Digikey. The 2SC1815/2SA1015 are available from BD Enterprises.

The 2SC1815/2SA1015 are also available from MCM.

 

[dgardner]

Can anyone tell me what the hole spacing, hole size, and body diameter would be for Black Gate caps in the 100-200uF range. I can't seem to find a datasheet out there. Right now, I have 0.300" leadspacing for eletrolytic bulk caps. I've heard that's too small for Black Gate users. Help!


I found ELNA Cerafines Caps. These have 10mm diameters and 5 mm lead spacing. Should live happily in a 0.200 lead space cap footprint if the holesize is generous enough.

What other esoteric electrolytic caps do people want to be able to use???

 

[Garbz]

What that's not what i said further up. 300mils holespacing is fine for 470uf 16v blackgates which I use in my Dynalo. 200mils (5mm) is suitable for the 220uf 25v BGs i had in my old one.

Also now that i've got mine working i can confirm that a 1k pot inplace of the 500ohm bias resistor does wonders for DC offset. No matching required

 

[dgardner]

Garbz - what's the body diameter on the .300 caps?

 

[Garbz]

600mils

/EDIT: take a guess what changed in this post

 

[dgardner]

EDIT: See post below for latest updates...

I'll add some notes to this thread about the layout. But for now, here is something to look at...

 

[skyskraper]

hey has there been any progress on this?

im assuming this is a lot easier to work on then the dynahi, and can fit in a smaller enclosure? if so then im in

 

[dgardner]

Update hopefully tomorrow....

 

[dgardner]

Schematic

Bottomside and Silkscreen

Bottomside, Silkscreen, Ground plane

Silkscreen and pads

Fabrication

Please take a look and provide any comments you have.

Notables:
Fits a Eurocard size.
Two amps per board each with a servo. (bridgeable for one XLR input).
Plenty of capacitor size options.
Pots in desired locations.
Two layer construction with power and ground planes.

Target date for first pass ordering of about a dozen boards is end of the day 12/22/2004.

 

[dgardner]

10 peices of the first pass boards have been ordered. Anyone with an interest in building up a few can PM me.