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R1155 info req
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 |
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 |
On Mon, 13 Oct 2003 22:21:13 GMT, Gregg wrote:
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. So helpful! |
On Mon, 13 Oct 2003 22:21:13 GMT, Gregg wrote:
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. So helpful! |
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