More on Pantry Transmitters.

[Joe]

Here we go:-

   

Time-base set to 0.5ms/Div, top trace output at 10mV/Div, bottom trace 500c/s AF in at 10mV/Div.

Not pretty but it does work.

- Joe

[pwdrive]

A bit less modulation maybe.

Lawrence.

[AlanBeckett]

Yes, turn the af down a bit.
Nice traces otherwise.

Alan

[Joe]

Same 'scope settings but I wouldn't now regard the output as being of a usable strength, unless via a direct connection to the aerial socket.

   

- Joe

[pwdrive]

That's better from a modulation perspective, maybe the carrier frequency is a bit low for a Collpits to give a decent output, maybe an RF choke in the emitter leg of the tuned circuit? Could you convert it to Xtal?

Lawrence.

[Joe]

It's not something I've any intention of using, Lawrence and I only built it to see if it would actually work.

As I said earlier it would be plenty good enough if built into a set with no Gram socket especially if it was a live chassis one as there'd be no direct connection.

- Joe

[pwdrive]

I'm with you now.

Just out of interest are these micro transmitters legal to use? If so would it be legal to key them?

Lawrence.

[Joe]

No - they are illegal throughout the EU. This has been covered in other threads which I'll try and find.

- Joe

[pwdrive]

Thanks Joe, it must be something to do with transmitting modulation, having said that it's what a signal generator does in many cases.

Lawrence.

[Joe]

The full legal position is here http://golbornevintageradio.org/forum/showthread.php?tid=484. I'm sure David will be only too happy to expand thereupon.

- Joe