Recent content by temol

I've just checked Malachite schematic I have - no R21/100K. I've also compared Sanguine and Malachite build docs. There is one resistor missing on the Malachite pcb layout drawing (upper right corner). But.. R21 is present on the Malachite pcb image here. Aaand.. if you take a look at the post...

G2 = G4 except: C3: 100p to 47p R13: 33k to 82k R14: 10k to 22k C11: 100p to 120p R18: 150k to 22k R21: 100k to - not present C21: 47n to 10n R29: 10k to 22k C26: 100p to 47p R31: 10k to 15k

You need a PSU that can give you 1A to 2.5A, depending on the type of the power amp. Because of this you cannot use any of the poplular charge pumps we usually use. Traditional power supply would be big and heavy (transformer). I'd search for good quality switched power supply.

If the Source is in the middle it's ok.

JBoss - you can use SMD version of the 5457 - MMBF5457. You can also use 5458 - gain of the stage with 5458 will be slightly lower than with 5457. To compensate for this you can increase value of the drain resistor from 22k to 24k. But you can also leave the original value. T.

You can start with biasing each transistor @ 4.5V (measure voltage on a drain of the transistor). Then experiment :) . Make slight adjustments - for example go up and down 1V wiht 0.2V steps and find the best setting for you.

Buy MMBFJ201. Do not waste time and money for replacement/equivalent transistors.

You can also swap places Q1 and Q2 and check the voltage on Q2. This way you'll know if it's the transistor or something else.

Q5 voltage is ok (9V on a drain). As for the Q2 - check value of the source resistor. Maybe it's 180R instead of 1k8? ps. use transistor numbers from the schematic, not their positions on a pcb :)

Do not buy J201. Buy MMBFJ201 - smd (sot23 package) version. Stay away from ebay/aliexpress J201 in to92 package. T.

No, 2N5458 is not a replacement for a J201 in a gain stage. T.

It's me again... can we see the schematic for the noise gate part? pretty please :) T.

Easier to dial in with genuine transistors. So rather stay away from to92 package J201's. T.

You should hear a difference using 50mH inductor, and that's only 1/5 of the required value. Of course you need "proper" inductor to hear the difference :)

You mean replacing 250mH with 250uH? According to the ltspice simulation 250uH inductor equals to no inductor. From left ro right - 500mH, 250mH, 100mH, 50mH, and three overlapping traces - 1mH, 250uH, inductor shorted.