1.if i change the varriable cap in an fm trnasmiter circuit to a pema cap will i maintain a single frequenciy?
2.doe's anyone has a diagram for an fm Transciver?
im sorry for my bad english
I've seen numerous FM transceiver projects described in amateur radio publications over the years. The ARRL Handbook is published annually - check 1960s and 1970s editions. I'll state what might be obvious to some - that these projects are aimed at licensed radio amateurs. You will find that transmitter characteristics and frequencies can be different for each country.
I've seen numerous FM transceiver projects described in amateur radio publications over the years. The ARRL Handbook is published annually - check 1960s and 1970s editions. I'll state what might be obvious to some - that these projects are aimed at licensed radio amateurs. You will find that transmitter characteristics and frequencies can be different for each country.
It was a typo-- i meant, when a satation is tuned, the antenna coil is also tuned by a section of the capacitor.
now when you want to used a fixed cap, and try for a stastion, the antenna coil is also to be tuned by some way by another fixed coil-
perhaps it is made more clear than simply saying antenna to be optimized.
A tuned circuit consisting of a capacitor and an inductor is often employed to determine the operating frequency of a transmitter, receiver or transceiver. Quite often the inductor is fixed and the capacitor is variable allowing for small or large adjustments in operating frequency. It is also common to fix the capacitor then vary the inductor with a slug of metal or ceramic. The inductor is often wound on a form - with the slug passing thru the center. As the slug is inserted or withdrawn from the center the inductance changes.
Some stages including the final connections to the antenna are set up to cover a range of frequencies. An example might be an AM radio designed to receive 530 to 1700 kHz. If the operator chooses to fix the frequency of operation one might choose to adjust or modify the various stages for optimum performance on that single frequency. In the case of the antenna one might modify or adjust it for maximum on that fixed frequency to provide better performance.
Permeability Tuned Oscillator (PTO) was employed by a number of amateur radio equipment manufacturers - in addition to the car radios mentioned. I do not recall what the benefits were over a variable capacitor except that it might have simplified the mechanical construction.
Permeability Tuned Oscillator (PTO) was employed by a number of amateur radio equipment manufacturers - in addition to the car radios mentioned. I do not recall what the benefits were over a variable capacitor except that it might have simplified the mechanical construction.
Permeability Tuned Oscillator (PTO) was employed by a number of amateur radio equipment manufacturers - in addition to the car radios mentioned. I do not recall what the benefits were over a variable capacitor except that it might have simplified the mechanical construction.
It is a issue of the past-- the reason appears to me is -- effect of vibration while car is sinmotion, can be prevented by permeability tuning- while the variable capacitor resonates.