Hi, can anyone tell me if the BFO freq on this set
runs at half the IF ie 280khz before I go mad
from Ron...

I don't know the circuit or radio, but it's a common trick to run an
oscillator a 1/2 it's intended output (use it's second harmonic) for
better spectral performance as well as oscillator loading stability.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

I don't know the circuit or radio, but it's a common trick to run an
oscillator a 1/2 it's intended output (use it's second harmonic) for
better spectral performance as well as oscillator loading stability.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

Hi,

Hi, can anyone tell me if the BFO freq on this set
runs at half the IF ie 280khz before I go mad
from Ron...

Yes, it does!

I guess they used the second harmonic to reduce the de-
sensitization that could happen if the BFO were at the IF
frequency and activated the AGC. It might also have helped to
reduce pulling of the oscillator by a strong IF signal.

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.


Cheers - Joe

Hi,

Hi, can anyone tell me if the BFO freq on this set
runs at half the IF ie 280khz before I go mad
from Ron...

Yes, it does!

I guess they used the second harmonic to reduce the de-
sensitization that could happen if the BFO were at the IF
frequency and activated the AGC. It might also have helped to
reduce pulling of the oscillator by a strong IF signal.

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.


Cheers - Joe

"Joe McElvenney" wrote in message
...
Hi,

(snip)

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.

Cheers - Joe

It's been a while since I passed these up in Lyle Street, London, UK, at "10
quid each" in the 1950's (some new, big mistake!) BTW, didn't they have one
of the best slow motion drives going at the time?

Cheers,

Roger
--
Roger Jones, P.Eng.
Thornhill, Ontario
Canada

"Friends don't let friends vote Liberal"

"Joe McElvenney" wrote in message
...
Hi,

(snip)

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.

Cheers - Joe

It's been a while since I passed these up in Lyle Street, London, UK, at "10
quid each" in the 1950's (some new, big mistake!) BTW, didn't they have one
of the best slow motion drives going at the time?

Cheers,

Roger
--
Roger Jones, P.Eng.
Thornhill, Ontario
Canada

"Friends don't let friends vote Liberal"

Hi,

I have quite a bit of info on this set, including pictures, circuits,
component layouts, model variants etc. Plus companion Tx, the T1154.

See http://www.zipworld.com.au/~sb/radio/

Simon VK2UA

On Mon, 13 Oct 2003 23:46:50 +0100, Joe McElvenney
wrote:

Hi,

Hi, can anyone tell me if the BFO freq on this set
runs at half the IF ie 280khz before I go mad
from Ron...

Yes, it does!

I guess they used the second harmonic to reduce the de-
sensitization that could happen if the BFO were at the IF
frequency and activated the AGC. It might also have helped to
reduce pulling of the oscillator by a strong IF signal.

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.


Cheers - Joe

Hi,

I have quite a bit of info on this set, including pictures, circuits,
component layouts, model variants etc. Plus companion Tx, the T1154.

See http://www.zipworld.com.au/~sb/radio/

Simon VK2UA

On Mon, 13 Oct 2003 23:46:50 +0100, Joe McElvenney
wrote:

Hi,

Hi, can anyone tell me if the BFO freq on this set
runs at half the IF ie 280khz before I go mad
from Ron...

Yes, it does!

I guess they used the second harmonic to reduce the de-
sensitization that could happen if the BFO were at the IF
frequency and activated the AGC. It might also have helped to
reduce pulling of the oscillator by a strong IF signal.

A great receiver for its day although the build-state was
typical Marconi of the time. I think however, that the average
operation life of a Lancaster precluded the receiver ever
reaching old age.


Cheers - Joe

Engineer wrote:

Cheers,

Roger
--
Roger Jones, P.Eng.
Thornhill, Ontario
Canada

"Friends don't let friends vote Liberal"

Roger. What happened during the recent election ? My brother and
two sisters say that they didn't vote Liberal, so want to know who did ?

Regards
Reed - VE1NU



-------------------------------------------------

Looking for information on the following

Marconi SMR-3 receiver
Northern Electric R8119A receiver and
KING, Director KX150 dual comms and nav receiver
and
Rogers Majestic (Motorola design)trunk mount FM radiotelephone
1949 RCAF Receiver Type CPA 8333 A/12 volt
Ref. No. 10EU/5820-21-801-4183
1949 RCAF Transmitter Type CPA 8329 D/12 volt
Ref. No. 10EU/5820-21-801-4182