Bring on da muthafukknin tru0!
ge mig en BOM så jag vet om jag behöver handla nåt!
Från em av herr F själv:
1) CA3280 OTA. This is the heart of the VCO. I tried an LM13700 but it was quite a bit inferior. Bridechamber is stocking the 3280, and I have a large stash of my own, which I will let Scott have if he needs more.
2) VN0104 MOSFET. Two of these are used for the integrator discharge switches. The switches have to swing a large voltage, due to the bipolar signal, and the low capacitance of this device makes a big difference in the reset signal. They are not rare or expensive, really, probably just a bit unfamiliar to most builders. 42 cents at Mouser.
3) A pair of matched 4.3V zener diodes. Buy 10 or so, measure their breakdown voltages and pick the best pair.
4) One pair ea of LM336-5 for the subregulated 5V supplies.
5) One pair ea of 3.3V zeners and 5.1V zeners for comparator decoupling.
6) MAT03 matched super transistor pair for the expo current source. SSM2220 is probably OK and has the same footprint. I've been using 2SA798, and the board will also take that.
7) One OPA2227 precision opamp for the expo converter circuit. OPA2134 would be just about as good.
8) 2 ea OPA134 and 2 ea OPA2134. Where low leakage/high speed are needed.
9) 2 ea LM311 high-speed comparators. For the two ramp resets.
10) Other opamps: 1 ea TL072 (or similar); 2 ea TL071 (or similar); 2 ea LM741 (for spike reduction).
11) 2k 3300 or 3500 ppm tempco resistor.
12) 6 ea ferrite beads. The power supply is split into three separately decoupled branches.
13) +/- 12V power supply. That's all I can support right now. I'll try to eventually do a +/- 15V version, but I don't want to give suggested changes without trying them out. For sure, the 5.1 and 3.3 V zeners will need to be increased, probably to 8.2 and 6.4 V.
Antar de löst 15 volts grejen. Men kollar det med Scott sen....
För de som inte har ca3280 så kan jag köpa det samtidigt från brudkammaren. Tempco med. Ev så kör vi även kits på det här. Om ork finns
