Immediately you say "choke" you have modified and peaked the bandwidth.
I'll buy that you can feed it with a resistor for broadband, but in my
humble opinion the construction of a grain of wheat bulb won't get up into
the UHF region with noise. Do you have any idea of the output level of this
circuit?

Jim



"Mark" wrote in message
oups.com...
I have seen a small "gain of wheat" type light bulb used as a noise
source...

Feed it with DC through a choke and AC couple the noise out ....

and you can vary it too!!

Mark

Try this
http://www.noisecom.com/

"RST Engineering (jw)" wrote in message
.. .
Immediately you say "choke" you have modified and peaked the bandwidth.
I'll buy that you can feed it with a resistor for broadband, but in my
humble opinion the construction of a grain of wheat bulb won't get up into
the UHF region with noise. Do you have any idea of the output level of
this circuit?

Jim



"Mark" wrote in message
oups.com...
I have seen a small "gain of wheat" type light bulb used as a noise
source...

Feed it with DC through a choke and AC couple the noise out ....

and you can vary it too!!

Mark

I've used noisecom for some years, but they are hard to buy in
onesie-twosies and are rather expensive in quantity when you only need one.

They USED to sell seconds that didn't meet spec, but I don't see that offer
on their current website.

Jim



"Clark" wrote in message
...
Try this
http://www.noisecom.com/

Just ask for samples, I got five of them a few years ago.


"RST Engineering" wrote in message
.. .
I've used noisecom for some years, but they are hard to buy in
onesie-twosies and are rather expensive in quantity when you only need
one.

They USED to sell seconds that didn't meet spec, but I don't see that
offer on their current website.

Jim



"Clark" wrote in message
...
Try this
http://www.noisecom.com/

depends upon the resistance and temperature of the filament

a small grain of wheat bulb will work to 500 MHz..


Mark