Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and wireless
doorbell buttons etc.

Any help appreciated.

TIA.

ian field wrote:
Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and wireless
doorbell buttons etc.

Common base Colpitts, perhaps:
http://en.wikipedia.org/wiki/Colpitts_oscillator

--
Regards,

John Popelish

On Mon, 25 Aug 2008 16:25:02 +0100, "ian field"
wrote:

Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and wireless
doorbell buttons etc.

Any help appreciated.

TIA.


This one?

http://en.wikipedia.org/wiki/Colpitts_oscillator

There are other common-base oscillator configurations.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"Spehro Pefhany" wrote in message
...
On Mon, 25 Aug 2008 16:25:02 +0100, "ian field"
wrote:

Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and
wireless
doorbell buttons etc.

Any help appreciated.

TIA.


This one?

http://en.wikipedia.org/wiki/Colpitts_oscillator

None that I've seen so far have C2 as in the wiki entry.

On Mon, 25 Aug 2008 17:27:35 +0100, "ian field"
wrote:


"Spehro Pefhany" wrote in message
.. .
On Mon, 25 Aug 2008 16:25:02 +0100, "ian field"
wrote:

Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and
wireless
doorbell buttons etc.

Any help appreciated.

TIA.


This one?

http://en.wikipedia.org/wiki/Colpitts_oscillator

None that I've seen so far have C2 as in the wiki entry.

C2 is free in a bipolar device.

RL

"legg" wrote in message
...
On Mon, 25 Aug 2008 17:27:35 +0100, "ian field"
wrote:


"Spehro Pefhany" wrote in message
. ..
On Mon, 25 Aug 2008 16:25:02 +0100, "ian field"
wrote:

Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to
emitter?

These are common in very cheap TV modulators and 433MHz keyfob and
wireless
doorbell buttons etc.

Any help appreciated.

TIA.


This one?

http://en.wikipedia.org/wiki/Colpitts_oscillator

None that I've seen so far have C2 as in the wiki entry.

C2 is free in a bipolar device.

In the lack of any better suggestions I'm looking into the possibility that
it might be a capacitively coupled variant of the Meissner oscillator.
Although it probably has a name of its own.

Reinartz? But that has two coupled windings in the C and E circuits.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

"ian field" wrote in message
...
Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and
wireless doorbell buttons etc.

Any help appreciated.

TIA.

Colpitts. They are using Cob as the capacitor from collector to emitter
through the AC grounded base.

Jim

--
"It is the mark of an educated mind to be able to entertain a thought
without accepting it."
--Aristotle


"Tim Williams" wrote in message
...
Reinartz? But that has two coupled windings in the C and E circuits.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

"ian field" wrote in message
...
Anyone know the correct name of the oscillator which is essentially a
grounded base amplifier with a small capacitor from collector to emitter?

These are common in very cheap TV modulators and 433MHz keyfob and
wireless doorbell buttons etc.

Any help appreciated.

TIA.

"Tim Williams" wrote in message
...
Reinartz? But that has two coupled windings in the C and E circuits.

That's the oscillator that the Raymond Haigh series of articles in the 1999
issues of EPE describe as a Meissner, this oscillator was fairly common in
pocket radios of the 70's era, I wondered if the oscillator I'm trying to
identify was a capacitor coupled variant.