Don't let them scare you. They're veterans, you know.
If you have a good vocabulary, many of the technical terms are self-explanatory. With a good memory, the bits and pieces you read eventually come together and you suddenly discover you know how tolerance works. A calm mind also greatly aids in remembering what you read and being able to put it into practice dynamically.
Much of the above is available at youth, and one must learn to use it wisely while it is there. Believe me, a strong being of self (and not just a "sense" of self) allows one to be far more aware of their reality and to use their special abilities at command. Discovering Self is the most important journey in life and living comes after this, not before.
Etc.
The key is focus, on life in general. This includes the past, the future, the ever-present NOW. It also includes dusting the chips off whenever the drywall collapses. Over time we (hopefully) learn to breakdown our "boxed" thinking but the structure has to collapse before this happens. If you allow the change to come naturally, it is much more bearable and you are faster to your feet when it all ends.
I agree with Andrew, I don't think this is so off-topic. But it depends on Daniel how much "bandwidth" we wish to cover.
Many threads like this have a tendency to drop cold, something I don't like to see. I do hope we end up with a finished project, and a nice picture of Dan in his victory pose.
- keantoken
If you have a good vocabulary, many of the technical terms are self-explanatory. With a good memory, the bits and pieces you read eventually come together and you suddenly discover you know how tolerance works. A calm mind also greatly aids in remembering what you read and being able to put it into practice dynamically.
Much of the above is available at youth, and one must learn to use it wisely while it is there. Believe me, a strong being of self (and not just a "sense" of self) allows one to be far more aware of their reality and to use their special abilities at command. Discovering Self is the most important journey in life and living comes after this, not before.
Etc.
The key is focus, on life in general. This includes the past, the future, the ever-present NOW. It also includes dusting the chips off whenever the drywall collapses. Over time we (hopefully) learn to breakdown our "boxed" thinking but the structure has to collapse before this happens. If you allow the change to come naturally, it is much more bearable and you are faster to your feet when it all ends.
I agree with Andrew, I don't think this is so off-topic. But it depends on Daniel how much "bandwidth" we wish to cover.
Many threads like this have a tendency to drop cold, something I don't like to see. I do hope we end up with a finished project, and a nice picture of Dan in his victory pose.
- keantoken
Know what?
Now, kids, this is what happens when you have TOO MUCH BASS.
I once tried to breadboard one of my circuits. Nothing I've ever tried to breadboard has ever worked. Once I kidded myself into thinking that I'd just point-to-point solder everything from then on.
In one of my circuits, I turned the pot a bit too far. It started glowing this strange orange color inside, spewing out smoke that did not rise.
Perhaps this can be utilized for stage effects.
- keantoken
Now, kids, this is what happens when you have TOO MUCH BASS.
I once tried to breadboard one of my circuits. Nothing I've ever tried to breadboard has ever worked. Once I kidded myself into thinking that I'd just point-to-point solder everything from then on.
In one of my circuits, I turned the pot a bit too far. It started glowing this strange orange color inside, spewing out smoke that did not rise.
Perhaps this can be utilized for stage effects.
- keantoken
the finished thing is done (on 1/1/09 to be exact, as promised)
http://71.203.202.83/pdf1/Electronics/Projects/Audio_amp/Frugalamp/
It is FA1_full.zip ...all dan needs is some laser printer/copier
time and a clothes iron..
OS
ostripper said:
I need some ,too..
OS
Howabout some gin&tonic's instead? Good enough?
I was playing, trying to discover what happens when you try to pipe an audio signal through only a diode. Well, that's an awful noise. However, I grabbed a big red LED, and it sent a nearly-clean signal, albeit less volume.
Okay, that's quite the difference.
AndrewT said:
How? line level source, diode in series with the input of a hi-gain amp. Not a recommended practice by any means, but it was interesting.
The 5v LED wasn't harmed. It didn't light up. It was also quite difficult to tell any difference in audio output from polarity.
But, there was a huge difference between the LED and the regular diode.
The regular diode became warm, wheras the LED was unimpressed and would not have failed.
The regular diode made really loud distortion, wheras the LED was quiet and mostly clear.
That's because the diode has .6-.7V forward voltage
and the red led 1.7-2V (green yellow 2.2-2.5v, blue-white 3.5-4v)
Led's are very useful for CCS/cascode voltage sources,
(not at all usable for small signal {ac} use)
with so many different suppliers and doping (GaAlAs,Ingaalp,etc.),
it is best to power it up first to determine it's characteristics.
As far as failure, I've seen 20year old consumer
electronics with working LED's (the only components that
still were usable).
OS
danielwritesbac said:
Dan, you need to learn how things work. A diode will not forward conduct until it is biased "on". This is the voltage needed to turn the device on, same as a transistor. Once on, it will conduct - one way, of course.
An LED is a diode (light emitting diode) and below it's forward on voltage, no current will pass.
MJL21193 said:
Oh yes. I had already gotten this clue because of my urge to add a larger and larger resistor to 1N1418, which, if given a large enough resistor value, probably turned off the diode. That's when it quit making terrible noises. However, a small amount of signal still passes. Why is this?
Speaking of noises, I finally made a radio that doesn't makes noises. That was the 7th try. Really, I just wanted the tuner to work, but the thing sure did exceed my expectations. We're jammin out to "Classic Top 40" right now. That thing beats the snot out of my Super DX on fidelity. Its awesome!!! Never give up, never surrender! (Galaxyquest movie reference).
Hmm, 85 mi range. Okay I'm off to play with a BF184. I don't own anything that doesn't have some sort of "boost" feature.
EDIT: Transistors are cool!
Are you using ceramics for input caps? The one I can see is 10nF.
Use electrolytics, 10-47uF. You won't hear a thing using caps that small.
That looks weird. Do you have aschematic?
Also, the 2N5769 is actually a switching transistor, I use it mainly because of it's low junction capacitance. It has very low beta (78) and won't work very well I don't think for an amplifier. You should probably go with something like a bc550 or 2N4401, 2n5089 (my favorite).
- keantoken
Use electrolytics, 10-47uF. You won't hear a thing using caps that small.
That looks weird. Do you have aschematic?
Also, the 2N5769 is actually a switching transistor, I use it mainly because of it's low junction capacitance. It has very low beta (78) and won't work very well I don't think for an amplifier. You should probably go with something like a bc550 or 2N4401, 2n5089 (my favorite).
- keantoken
Its an FM antenna amplifier. http://braincambre500.freeservers.com/rf amplifier.htm Mine is actually running on 12.5vdc.
keantoken said:
I don't know. Okay, maybe an ecap for power smoothing? That's just a guess.
I'd sure like to know if something is missing (hint, hint).
Its hooked up on the radio now, and had the effect of preventing the radio from flipping between mono and stereo, and it also lights up the tuning light brighter than before. Its possible that the little amp actually works?
It seem like it's working. If it's powered with a battery you probably don't need a smoothing cap.
Stereo FM works by tuning to two separate frequencies for the different channels, so your amp could be interfering with the tuning.
Also, the 2N5769 is not an RF transistor. You might take inventory and look at datasheets to see which transistors have the highest Tf.
- keantoken
Stereo FM works by tuning to two separate frequencies for the different channels, so your amp could be interfering with the tuning.
Also, the 2N5769 is not an RF transistor. You might take inventory and look at datasheets to see which transistors have the highest Tf.
- keantoken
keantoken said:
Yes, there's at least two mistakes. The reference (that was measured) has a polyester cap, which is RCR (approx 7c7), and that's different from my ceramic, which is C (approx 1c1). And, since its an RF component, I need to either give it a huge ground plane directly underneath or put it into a grounded (0v rail) little metal box.
So, probably mine isn't as stable as the reference. Considering those errors any rf thing should be freakin out.
It seems beneficial, though. The radio stopped drifting anyway. It stays locked on and the tuning indicator brilliant green instead of faded. I just can't believe it was so easy! I'm so amazed. One transistor can do this?
Just like the audio amp errors, I think I have the input filter cap mistakenly too big in relation to the rest of the design. What do you think? Too big for 80mhz?
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