pirate radio transmitter components + eliminating hum & interference

Pirate radio transmitter components.
Below where to buy:

http://www.progressive-concepts.com/index.php
http://www.jtcomms.com/
http://store.rf-modules.com/
http://www.ramseyelectronics.com/
http://www.panaxis.com/

important! low pass filter:
http://www.progressive-concepts.com/info/item.html?id=375

Cast Aluminum boxes:

Mouser Electronics
http://www.mouser.com/catalog/636/1873.pdf
MCM Electronics
http://www.mcmelectronics.com/browse/Large/0000000736

To help one stay out of trouble, each pc board of whatever device should be mounted in its own metal box. Each + audio and D.C. power lead should be bypassed with a .001 uF capacitor, one side of the capacitor to the lead and the other to the metal case. The ground lead of the audio and D.C. power lead should be directly mounted to the metal box or rf bypassed to ground with a .01 uF capacitor, one side of the capacitor goes to the metal case and the other to the ground lead. At a minimum, there should be an RF low-pass filter on the last RF amplifier stage before the coax feeding the antenna. A deviation limiter should also be employed. PLL should be used to stay on frequency.

How to eliminate RF feedback problems. This is heard as hum and buzzing in the audio equipment such as a cd player and microphone. The audio and power leads leading in and out of such equipment must be RF bypassed! The audio is done in the same manner as the audio leads that pass through the metal box in any of the FM or AM transmittter components. For ac power leads make sure that the voltage rating of the capacitor is much greater than 120volts or 240volts. Both of these ac power lines(hot and neutral) cannot be connected directly to the metal case. They both must be bypassed with a .001 uF capacitor!

The total length of leads of the rf bypass capacitors must not be any longer than about 2"!

For microphones that hum and/or have a buzzing noise, do the same as for the audio lines. If after by passing with a capacitor there is still some noise, try a balanced line and a balanced line microphone. Radio Shack carries them. I have completely eliminated any RF feedback problems.

Here is a picture of how to do all of this:
http://mysite.verizon.net/vzeo38ur/rfbypassing.jpg

Pirate radio guide
http://libcom.org/organise/pirate-radio-guide

Please feel free to ask for any help.

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[DarkMystic182]

I see a ton of links for components, but no link to a schematic?

[jimbobubbadj]

@DarkMystic182 Its near the bottom, under the "more info" section where one can buy components. This is it here "Here is a picture of how to do all of this:" I would post a link here but YT does not allow links in the comments section.

[johnu78]

Great setup!

[jimbobubbadj]

@johnu78 Thanks!

[poirob2]

dude, could you post a link to the schematics of how to build something like this?

[jimbobubbadj]

@poirob2 Its in the info section of the video, click view more below the video. Just click the link. If you can't find it let me know. Good luck.

[heresboomer]

What a classic lineup! I always saw Stellatron exciters in electronics magazines and wanted one, but never could afford it as a student.Oh, to put out an actual stereo signal was a dream then.. I think the one I wanted was 20 milliwatts output. Thanks for the show-and-tell and memories..

Boomer

[DarkMystic182]

@jimbobubbadj Oh, so this video is only talking about where to buy general components and how to filter out the noise? I was looking for a schematic for the transmitter

[maikaamer1337]

thats that , but does it bend ?

[khaled6100]

cool thanx