using led as cathode resistor

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johnny riff
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using led as cathode resistor

Post by johnny riff »

greetings
ive been playing with LEDS as a cathode resisor.
v1b mostly. thoughts?
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xtian
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Re: using led as cathode resistor

Post by xtian »

johnny riff wrote: ↑Tue Mar 10, 2020 3:06 amthoughts?

You can use an LED as a...SQUIRREL!
I build and repair tube amps. http://amps.monkeymatic.com
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xtian
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Re: using led as cathode resistor

Post by xtian »

What kind of thoughts were you hoping for?
I build and repair tube amps. http://amps.monkeymatic.com
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sluckey
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Re: using led as cathode resistor

Post by sluckey »

I've been using a red or yellow LED in the cathode of tremolo oscillators for some time now. Much stronger tremolo signal plus a blinky lite on the front panel if you like eye candy.
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johnny riff
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Re: using led as cathode resistor

Post by johnny riff »

sluckey wrote: ↑Tue Mar 10, 2020 10:50 am I've been using a red or yellow LED in the cathode of tremolo oscillators for some time now. Much stronger tremolo signal plus a blinky lite on the front panel if you like eye candy.
I got the idea from you on another site.
I had only red on hand and it seems to be working well for v1b for a Princeton 5f2a based amp with an el84 output.
I considered getting some different colors to experiment with.
Have you noticed them different sounding per color and voltage/current ratings?
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johnny riff
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Re: using led as cathode resistor

Post by johnny riff »

xtian wrote: ↑Tue Mar 10, 2020 3:32 am You can use an LED as a...SQUIRREL!
"SQUIRRELS" as in tree rats? that's not an amp term I'm familiar with..
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xtian
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Re: using led as cathode resistor

Post by xtian »

Squirrel! As in..

Image
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sluckey
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Re: using led as cathode resistor

Post by sluckey »

Have you noticed them different sounding per color and voltage/current ratings?
The circuits I use them in operate at 3Hz to 10Hz. They all sound the same to me. :mrgreen:
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roberto
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Re: using led as cathode resistor

Post by roberto »

xtian wrote: ↑Tue Mar 10, 2020 3:32 am You can use an LED as a...SQUIRREL!
:mrgreen: :mrgreen: :mrgreen:
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roberto
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Re: using led as cathode resistor

Post by roberto »

I would avoid to usue them in stages that overdrive easily. At least I don't like how they sound.
Also remember you cannot shape alot the frequencies with leds, as their impedance is quite low.
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