7MHz cw - am transmitter

I made a simple cw/am transmitter for 7 MHz [hamradio]

The design is from Nitin VU3GAO.

Just one tube [EL84] and you are on the air.

As a modulator for AM I used a TDA2005, just one section because it's a stereo amp.

To finish it off a boxed it in a cabinet I had on the shelf.

Hamradio is always fun :-)

Link : http://nmwilliam.tripod.com/el84.html [original design - website VU3GAO]

Link : http://animals.home.xs4all.nl/files/TDA2005_AM_Modulator.jpg [Modulator]

Category:

Science & Technology

Tags:

• hamradio
• transmitter
• mhz
• 40meter
• 48meter
• 41meter
• pirate
• sender
• zender
• am
• cw
• homebuild
• homemade
• vu3gao
• pa3dmi
• zendamateur

[LZ2SM]

Hello!I am currently working on that project and the oscillator is working but I wonder would it matter if the coil is wound with thin copper wire?Will it drop the output power?

[PA3DMI]

@LZ2SM Hi Sergey,

The wire on the resistor is 22swg or 0,7mm, the wire on the tankcoil is 20swg or 1,0 mm.

Do not make it to small because the current has to go through the wire and if the Amps drops the outputpower drops.

Bye from Amsterdam

Jarno - PA3DMI

[m0dad]

Hello Jarno

I have also started building this transmitter so I was pleased when I came across your youtube video. Great video and I like the enclosure. I was wondering what you have used for the two 2.2mh rf chokes? Have you wound your own,used commercial chokes or used resistors instead?Thanks for sharing the video 73 M0DAD

david

[PA3DMI]

@m0dad Hi David,

I used commercial chokes. Maybe Maplin, or otherwise search the internet for the correct value.

Bye from Amsterdam

Jarno - PA3DMI

[m0dad]

HI Jarno

Do you know what voltage you have from the power supply off load?

Thanks M0DAD

David

[LZ2SM]

Thank you very much!The best I had was 0.8 mm wire and the dummy load bulb lights up really nice!Great project!

[perentaart]

ThebShadows are good. Nice casing for your transmitter btw!