[sdiy] Can I use two 1/4w resistors instead of one 1/2w ?

[Gil W.]

Interesting.

I ended up using a set of two 2.2K in parallel, connected in series with  a single 100ohm resistor, to create 1.2K . They are all 1/4w.

I then let the synth run for 10 minutes. It initially worked fine, but after a few minutes it froze.

I now see that using different values makes different current flow in each of the combined resistors, which is not what we wanted in the first place.

I'll just get a 1.2K 1/2W resistor today and use it I guess....

But as for the freezing, can we assume it's the resistor combination causing it (the resistors gets hot too much) or should I replace the regulators, for example ?



--- On Tue, 6/23/09, Magnus Danielson <magnus at rubidium.dyndns.org> wrote:

> From: Magnus Danielson <magnus at rubidium.dyndns.org>
> Subject: Re: [sdiy] Can I use two 1/4w resistors instead of one 1/2w ?
> To: "Gil W." <gil_we at yahoo.com>
> Cc: "synth-diy at dropmix.xs4all.nl" <synth-diy at dropmix.xs4all.nl>
> Date: Tuesday, June 23, 2009, 2:52 AM
> Hi Gil,
> 
> Gil W. wrote:
> > A theoretical question:
> > 
> > Schematic calls for a single 1.2K, 1/2W resistor.
> > 
> > What if I use two parallel 2.4K, 1/4W resistors
> instead ?
> > 
> > Will each one of them get half the current, making it
> possible to use the two 1/4W resistors instead of
> > on 1/2W resistor ?
> Yes, that works fine. The current will divide evenly due to
> the resistance match fairly well. Current balance between
> power transistors is done with the help of resistors.
> 
> Cheers,
> Magnus
>