cdwillis
Well-known member
Robert, can we get a BOM for this Scabbard overdrive?
Scabbard Overdrive
- Thread starter cdwillis
- Start date
AlphaMoose
New member
I figured I might point out for anyone getting parts together for one of these, SmallBear has a frankly stupid good deal on D9B diodes if you buy 100. https://smallbear-electronics.mybigcommerce.com/germanium-diode-soviet-era-d9b/
Bricksnbeatles
Member known well
Rad! Anyone tested the leakage on the small bear D9Bs? Based on the quantity in stock I’m guessing it’s from a lot of sources, and therefore might be pretty varied, but I’m curious as I’ve seen a lot of old posts from a decade ago about them being relatively comparable to 1n34A in leakage, but all of my D9Bs are super duper leaky
AlphaMoose
New member
I’ve never to my knowledge played around with D9Bs, but I did place an order for 100. If I remember (which is a big if tbh) I’ll report back once I get them and test a few
AlphaMoose
New member
Ok, I received the diodes this afternoon and I had a chance to check a small handful. My method of checking leakage may be primitive and/or wrong, so I gladly accept correction if I’m simply being dumb. I measured a random set of 20, by measuring their forward voltage drop with a DMM and then checking their resistance value in reverse. All of them were pretty consistent in terms of FV, right around .24v, as you might expect. Reverse biased resistance was in excess of 500kohms for all but 4 of the diodes. Of the remaining 4, 2 were in the high 300kohms and 2 were in the high 100kohms. I suppose whether that constitutes high or low leakage depends on your definition and needs but that’s what I found with my batch.
AlphaMoose
New member
I’m in the same boat, have to wait and see the schematic. IIRC the Longsword was stated to have “hard clipping” diodes and I know the Dagger is an outgrowth of the Longsword so I wouldn’t be surprised. And to be honest, I’m not entirely sure what kind of effect the leakage may have on the circuit in such a case. As far as using the other 98, at least for my part, I wound up discovering I liked them quite a bit in an overdrive circuit I’d been developing and thusly they provided the final puzzle piece to another finished design, so I’m not complaining.That's a crazy good deal, but am I ever going to use 98 more of these d9b diodes? Hmm.
Is leakage something to consider in a hard clipping circuit? I'm assuming this is some kind of hard clipper, but the schematic isn't out yet and I didn't trace the pcb when I got it.
