Hiya :)
Looking for schematics for AF filtering made from commonly obtainable parts. DSP a plus :p
Hiya :)
Looking for schematics for AF filtering made from commonly obtainable parts. DSP a plus :p
I've enjoyed island life for 17 years. That's 13 years more than the Confederacy was around.
RIP Albi
When do you tell a woman you're a ham?
It's a jungle out there. Many EQ stupidly with poor articulation.
~TKX
YIAH
"And, of course, the Gym Teacher being his usual self."
W3WN
"The enablers ride on the top of the pile."
WZ7U
“The basic tool for the manipulation of reality is the manipulation of words. If you can control the meaning of words, you can control the people who must use the words."
--Philip K. Dick
Charles, I have to take care of business this morning, but when I get back, I'll help you out here. You can purchase a small prototype board, a few inexpensive op-amps, and various resistors (resistor kit) and non-polarized capacitors between 1uf and 10 uf. We will build some filters!Originally Posted by KG4CGC
In the mean time, do an internet search on Sallen-Key low pass and high pass filters. We will start from there, and post the links here so we have a common source to discuss.
Chebyshev or Butterworth?
But, but, we don't need no stinkin' circuits...
http://www.io.com/~n5fc/res_spkr.htm
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
Reminds me of the old Dixie Cup cw speaker. Years ago some ham accidently discovered that a particular size of the plastic Dixie Cup line of plastic cups had a resonant freq of exactly 750 or 800hz? Outside it's self resonant freq it would hardly respond at all. I built one and it worked like a charm.
But, but, we don't need no stinkin' circuits...
It was about like the 100hz bandwidth audio filter in an R-390A, very careful tuning required or your received station went away instantly.
I don't know that it matters yet. I've looked at some stuff online, there are a lot of schematics out of the UK and Asia. Note that values there need some translation, for example: a 4K7 resistor in American terms translates to 4.7K.
Yes, I want to use commonly available parts from RS. Common ICs and transistors. I built a CW filter some years ago from a Vectronics kit but it had 4 set values and sounded hollow. Not good on the ears. Tried some freeware DSP software but I can't get past the excessive oversampling that results in echo echo echo. Using that last night, DSPFIL V1.0 2000 and BR-universal-Filt resulted about the same but the BR program seemed a little better other than having to figure out German to English translations. Yeah, stuff gets stuck in your brain from years of comedy in HS and somehow helps you figure out what foreign words mean LOL.
I may fiddle about with that old Vectronics kit some. I also have an assembled and unassembled amp consisting of a 1458 and a 386 op amps. I believe I can add variables "R's" and switched caps and fiddle about with those results.
I've enjoyed island life for 17 years. That's 13 years more than the Confederacy was around.
RIP Albi
When do you tell a woman you're a ham?
It's a jungle out there. Many EQ stupidly with poor articulation.
~TKX
YIAH
"And, of course, the Gym Teacher being his usual self."
W3WN
"The enablers ride on the top of the pile."
WZ7U
Very cool. Stuff that can be inserted in the first IF section would be of interest too :)Charles, I have to take care of business this morning, but when I get back, I'll help you out here. You can purchase a small prototype board, a few inexpensive op-amps, and various resistors (resistor kit) and non-polarized capacitors between 1uf and 10 uf. We will build some filters!
In the mean time, do an internet search on Sallen-Key low pass and high pass filters. We will start from there, and post the links here so we have a common source to discuss.
I've enjoyed island life for 17 years. That's 13 years more than the Confederacy was around.
RIP Albi
When do you tell a woman you're a ham?
It's a jungle out there. Many EQ stupidly with poor articulation.
~TKX
YIAH
"And, of course, the Gym Teacher being his usual self."
W3WN
"The enablers ride on the top of the pile."
WZ7U
It's hard to beat a nice simple Butterworth for voice band audio.
I don't know that it matters yet.
That's certainly something to take into consideration.It's hard to beat a nice simple Butterworth for voice band audio.
I don't know that it matters yet.
I've enjoyed island life for 17 years. That's 13 years more than the Confederacy was around.
RIP Albi
When do you tell a woman you're a ham?
It's a jungle out there. Many EQ stupidly with poor articulation.
~TKX
YIAH
"And, of course, the Gym Teacher being his usual self."
W3WN
"The enablers ride on the top of the pile."
WZ7U
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