DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: rosssurf on May 05, 2006, 01:02:49 AM

Title: How can a lower a Diodes foreward current?
Post by: rosssurf on May 05, 2006, 01:02:49 AM
I have a build (Flatline) that requires four 1n34a diodes. I just found out one of them must be bad. It reads no foreward current. I have a bunch of other 1N4148's but thier foreward current is much higher. can I series, or parallel the 1N4148's to get a lower foreward current somehow?
Title: Re: How can a lower a Diodes foreward current?
Post by: petemoore on May 05, 2006, 01:30:11 AM
  You're going to have to get or find a GE diode.
  An otherwise 'less desirable for gain' [because of leakage or gain] Ge Transistor has one in it.
Title: Re: How can a lower a Diodes foreward current?
Post by: rosssurf on May 05, 2006, 02:05:35 AM
Thanks Pete
Title: Re: How can a lower a Diodes foreward current?
Post by: George Giblet on May 05, 2006, 01:47:20 PM
You can't significantly change the voltage drop of diodes through paralleling.

You can use a Schottky diodes on one half of the rectifier with minimal effect on behaviour. For the sake a symmetry you should replace two of the GE diodes with Schottkys.  The diodes connecting together at the either of the opamp outputs should be of the same type.

Take care removing the Ge's otherwise they will crack.

There is no concept of gain or leakage for this circuit, it's all about voltage drop.
Title: Re: How can a lower a Diodes foreward current?
Post by: WGTP on May 05, 2006, 02:21:21 PM
R.G. mentioned the 1N5819 the other day as being Schottkey's with lower forward voltage.  My meter measured .223v on them.   :icon_cool: