I've read that 90% of VHF/UHF receiver noise is generated by it's own electronics. You can test this by pulling the ariel out of an analogue TV and noting that the noise drops only very slightly. Are you familiar with the noise that I'm talking about Dave - I mean from TVs, FM stereo tuners...
Thanks for that Dave. My experience of VHF and UHF is that, unlike longer wavelengths, you always get a massive burst of noise from the electronics when there is no carrier; hence the need for the squelch that ramussons mentioned. This applies to everything from television sets and quality...
Thanks ramussons, I was beginning to think that no-one was going to reply! That makes sense and if anyone has a mathematical explanation then that would be gratefully received.
Hi, Does anyone know why the circuit noise in a VHF or UHF receiver is so high when compared with a short wave or lower frequency receiver? Also, why does a carrier quieten the noise - is it just because the automatic level control kicks in, or is there real noise reduction in the circuits...