Light bulb radio

Fuzzy Clam

One for Watty maybe;)
Components found in a Philips energy saver (!) light bulb.
8 Diodes
10 resistors
6 capacitors
2 transistors
1 transformer
1 choke
1 ferrite ring with 3 sets turns

and maybe a little mercury:eek:

Enough to build a radio with I think. In fact with the transformer and all those diodes it could possibly work on mains voltage.

watty

I've used some of the parts in 90v Battery radio PSU...

The transformer is high frequency, useful maybe 15kHz to 50kHz

The transistors work direct on 275V DC. Four of the diodes are bridge on the mains. One of the capacitors is likely 4.7uF 400V.

You could certainly build a simple radio, but for safety run off battery rather than 275V direct and unisolated from mains :eek:

The RF Tech Guy

Rather than playing with HT voltages why not consider using a 9 Volt battery along with your list of parts.

You could make a very simple AM radio using the diode (probably silicon rather than germaninum) as the detector and the transistors and capacitors as an RF amplifier and an audio amplifier.

Some very simple info on crystal radios at this link http://sci-toys.com/scitoys/scitoys/radio/homemade_radio.html

A little more in-depth and requiring a few more components http://www.somerset.net/arm/fm_only_one_transistor_radio.html

A trawl of google will bring up a range of simple transistor designs.

Fuzzy Clam

No harm in "playing" with HT if you know what you doing.

The point I was really making was with that number of components, you can make a radio out of a light bulb, just about.
Personally, I probably won't actually make it.

The RF Tech Guy

Fair enough

watty

Yes, just a mind exercise.

There are ample components to make all kinds of stuff from Innards. Maybe I should run a competition with some sort of appropriate technical prize for the best ideas...
Categories:
* Most interesting, but not actually built.
* Most interesting and works
* A Radio or Radio related and works.
* most impressive construction and works

Ideally it should work off batteries.

Now to find a sponsor...
It would be on www.techtir.ie of course

amcc

this guy made an 80m cw transmitter and receiver out of parts from an old CFL -

http://www.aa1tj.com/dasderelicht.html
http://www.aa1tj.com/dasderelichtreceiver.html

Mike 1972

Interesting concept using fluorescent lights to enable one to listen to the radio. In my experience they tend to do the opposite

watty

Well, just the parts from the electronic ballast. The tube is of no use.

Even the traditional "choke" ballast fluorescent lamps generate RFI simply because it's Plasma discharge. But the electronic ones vary from a bit worse (filtered) to terrible (no filter).

Mike 1972

watty wrote: »

Even the traditional "choke" ballast fluorescent lamps generate RFI simply because it's Plasma discharge. But the electronic ones vary from a bit worse (filtered) to terrible (no filter).

There is a hell of a difference between different models though.

There are regulations regarding this sort of thing but are never enforced :mad:

Incidently mains operated LED lamps seem to be little better from an RF point of view

watty

They would be worse without better filtering.