On 5/2/07, earthtodylan2000 put forth:
>Hi,
>
>I'm working on the Ken Stone Power delay and Tube VCA projects for
>my MOTM system.
So what are you using for a panel?? :)
If you are buying it from Front Panel Express, perhaps we should try
to get a bunch of orders together so we can avoid duplicating set-up
charges, and get a volume discount.
>Trying to find the correct parts is driving me insane. Does anyone
>have the correct part #'s for mouser, digikey, or whatever for these
>projects?
Well, the parts for both those projects seem rather common. In fact,
except for the tubes, I might not have to order any parts to build
the Tube VCA. When I get the boards, I'll see if the caps and
trimmers I have fit (Bourns trimmers and those poly caps in the
little yellow boxes don't have much wiggle room with their tiny
leads).
Always use caps with an appropriate voltage rating, eg. 50-100V. For
the three capacitors in the signal path, I would use poly caps with
radial leads. Polyester, aka Mylar, caps are inexpensive and space
efficient but their dielectric absorption is terrible. So I would go
with either polycarbonate or polypropylene (tantalum caps are polar,
and polystyrene caps are large, expensive, and generally overkill).
For the bypass caps, please see Richard's last post on the CGS list.
The Tube VCA uses an op-amp which can swing to its negative rail (a
TL072 can't do that). Although not singular in that ability, the
LM358 specified by CGS is both inexpensive and widely available:
http://www.mouser.com/search/Refine.aspx?Ne=1447464+254016&Ntt=∗LM358∗&Msb=0&Mkw=LM358&N=1323038Just make sure that you order IC's in DIP packages!!
Also, while I'm typing, I'm thinking of using bullet connectors for
the tube. That way I can replace the tube without soldering the PCB.
Looking at the Power Delay, it uses a 741, which is an antique, but
afaik, you can still buy them. Although, you should be able to
replace it with a modern op-amp with the same pinout. The switching
transistor also seems pretty generic:
http://www.mouser.com/search/refine.aspx?Ntt=512-BC338Sorry, I have no idea which relay would fit.