Bought 3 different MN3007 from sellers on eBay to use in a Electric Mistress Clone.
Two refuse to work at all, one produces a tiny amount of flange along with a massive hum, as well as being too hot to touch after a couple of seconds.
Circuit has been tested with a genuine MN3007 I pulled from an old Boss chorus pedal and works perfectly, so I know it's definitely the chips.
Don't want to waste anymore time and money trying other eBay offerings. Anyone know of a reliable UK source for them? If not I guess I'll be putting an order in from Smallbear in the USA.
Bah.
Comments
Get them from Das Musikding or Banzai in Germany, they work.
Annoying from a design point of view as I doubted my own circuit design before I twigged
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
With something like these BBD chips, my guess is they're not fakes, but rejects that don't fulfil the specs on the datasheet and were binned by the manufacturer. Producing a chip, real or fake takes a tremendous amount of resources. I used to work in the chip industry, and faking was a problem, but the fakers have to have access to the litho mask data and a multi-million pound fabrication plant to produce them.
It doesn't seem that long ago that you could get ten 3007s off eBay for a fiver and they'd all work. Out of the last 30 I bought, precisely one of them worked. I got refunds, so no money was lost, but it's still a pain. None of them passed audio and most of them got hot.
They were all "pulls", and I suspect that they've probably been harvested by a four year old holding the circuit board over a fire (I've seen this on news reports). If the ICs aren't buggered by the heat, they'll have been zapped by static discharge.
I think I got my last few from Musikding. Not cheap by any stretch, but at least they worked.
I said maybe.....
I rarely buy components from eBay.
The price should tell you they are fakes.
Should have learned my lesson with the batch of eBay 600v caps that went leaky within a couple of hours running an amp build ...