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only as a quiet spot, a BFO is an oscillator built into the radio, found only on shortwave radios it operates at a slightly different frequency than the IF and is usually adjustable to create the desired tone when the CW transmitter is keyed this creates the beep beep sound you've heard in...
80 meters refers to the wavelength of the frequency - for instance a 1 wavelength antenna would be 80 meters long, this is the 3.5-4.0 amateur radio band - an excellent resource would be the ARRL Handbook - you can buy it or search for it somewhere else.
SiGiNT
CW is continuous wave with no modulation, so AM and FM do not apply it is simply a no sound quiet spot when listened to on a receiver, it only makes a sound when you have a BFO, (beat frequency oscillator), a built in feature on most shortwave receivers that adds a tone to it - exactly like one...
It looks as though your transmitter is for the AM broadcast band, (about 1 Mhz), the NTE replacement should work with no problem, you might want to make the 465 pfd variable or put a 100 Pfd variable in series with a 365 Pfd fixed or what ever the available closest is - it will allow you to...
I think you missed the point of my post, germanium transistors did not vary wildly in requirements, things were simple back in those days - the NTE100 is a general purpose replacement and may be a replacement for your transistor, but my recommendation just for educational purposes is to find a...
NTE100 is a germanium PNP transistor suitable for high frequency oscillation, you might be able to drop this into your circuit with little or no change. A cw transmitter is simply an oscillator operating at the desired frequency power is increased using amplifier stages.
SiGiNT
Aside from the predictable glitches on any new forum update, I like the look, however people were reporting lost history, I'd like to see that restored.
JMHO
SiGiNT
I see my registration date is closer to accurate, however I believe my post count is low - no big deal just a comment and a...
Re: Help with timer
Your timing cap should easily charge in less than a second, unless you have a limiting resistor in series with the charging source, if you are using a 555 you may want to switch to a simpler transistor switch.
SiGiNT
Re: pcb to screen problem
Make gerbers as cyberrat says, print to a PDF printer, (many free ones out there), at 11x17" size 1 to 1 then send PDF file.
SiGiNT
I use my computer 90% for engineering and Win 7 Pro has worked flawlessly for virtually everything, as opposed to Vista - which, when it functioned at all had problems too numerous to number, I couldn't be happier - not to mention a 50% greater download speed over XP - yes I still use XP but...
Re: rotation in allegro
Right mouse context menu allows you to set many parameters, remember the more expensive the software the less user friendly it becomes.
There are no doubt keystrokes, or you could define a mouse stroke for convenience, often not understood by Designers who've never used...
Re: Wire---frequency
Wire has no frequency limitations up to a reasonable frequency, (many GHz.), the property you should be concerned with is impedance, a bare wire in air has a dielectric constant slightly above 1 and would offer a high impedance as would a PVC covered wire, if your source is...
Re: ANTENNA HELP
My best results have been with plastic coathangers drilled out 1/4 wave and a metal rod glued to the interior, the base of the coathanger can be done like-wise to use as a tuning stub. coax may be soldered to the the first rod and the shield can be glued to the outside, be sure...
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