madbeanpedals::forum

General => Open Discussion => Topic started by: chromesphere on February 03, 2014, 07:59:21 AM

Title: My mn3005 Experience/nightmare
Post by: chromesphere on February 03, 2014, 07:59:21 AM
I saw a seller had them listed for $40 for 2 and thought, what the hell.  Tested the first one, not passing signal.  Tested the 2nd, worked and is definitely a 3005, has the longer delay.  Was using it for about 5 mins, bang, delay signals lost.  Mess around with the bias etc, nothing. 
The lesson in this for me is don't throw done so much coin on a 30 year old chip.  Now I have to go through all the ebay dispute bs to get my money back.  I know some people may be of the opinion that the 2nd chip wasn't faulty, as far as im concerned if your selling 30 year old chips for $20 each be expected for faulties.  I know I would.
Now im off to cry myself to sleep.
Paul
Title: Re: My mn3005 Experience/nightmare
Post by: Scruffie on February 03, 2014, 08:26:45 AM
If it has blown that was most likely down to not using ESD precautions which need to be taken with the BBDs, they don't just randomly die so I do think you shouldn't claim on that  :-\

Kinda sounds like it might be the pedal though and not the chip... or even chips.
Title: Re: My mn3005 Experience/nightmare
Post by: chromesphere on February 03, 2014, 08:42:14 AM
I was no where near the chip when it stopped working I cant see why it would be ESD.  Also, I've tested heaps of chips in this circuit, never had a problem (and probably never will after this experience).

is Styrofoam ESD protection?  According to the internet that would be a no.  This guy shipped then in Styrofoam.  Normally it probably wouldn't be a problem.  But for a $20 chip you would think that they would take some extra precautions.
Title: Re: My mn3005 Experience/nightmare
Post by: alanp on February 03, 2014, 08:42:55 AM
I'm not sure I'd ever take a gamble on Ebay BBD's -- I'd only buy them from Steve at SB, maybe PPP if I really, really wanted 'em. (I tend to go with SB, only bought from PPP once or twice.)

I'm okay with transistors and diodes from ebay, since they tend to be cheaper and sturdier, ESD-wise.
Title: Re: My mn3005 Experience/nightmare
Post by: Scruffie on February 03, 2014, 08:56:25 AM
Quote from: chromesphere on February 03, 2014, 08:42:14 AM
I was no where near the chip when it stopped working I cant see why it would be ESD.  Also, I've tested heaps of chips in this circuit, never had a problem (and probably never will after this experience).

is Styrofoam ESD protection?  According to the internet that would be a no.  This guy shipped then in Styrofoam.  Normally it probably wouldn't be a problem.  But for a $20 chip you would think that they would take some extra precautions.
Is it definitely the chip then, so you've switched back between the dead one and a verified one?

No styrofoam is not... well unless it's pink or black. Did this come from Asia I take it?

Guess you just got really damn unlucky.
Title: Re: My mn3005 Experience/nightmare
Post by: chromesphere on February 03, 2014, 09:11:53 AM
Yeah switched between my good ole 3008's.  Definitely gone.  Not the bias either, its in the same spot.

The styrofoam is white.  Yep came from asia.  For $20 a chip you would think these idiots would invest in a half square meter of conductive foam or some tubing...It was sealed in a foil pouch which is pretty much useless if they are shoving it in foam...
Title: Re: My mn3005 Experience/nightmare
Post by: juansolo on February 03, 2014, 09:16:29 AM
Stopped even trying on MN3005s a year or so ago. It's not worth the expense or effort these days.
Title: Re: My mn3005 Experience/nightmare
Post by: chromesphere on February 03, 2014, 09:56:03 AM
Im incredibly late to the BBD party.  Was hoping to have a couple of mn3005's kicking around.  Looks like that idea has gone out the window.  Or ill cough up twice what I paid for verified chips.  But idk...the mn3008's sound pretty good even if they are half the delay time.  And at least if one blows you don't slash your wrists. Pretty sure The Bean is working on a 4x3008 layout anyway  8)