View Single Post
Old 7th Feb 2019, 11:56 am   #10
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: Identifying resistor types?

Quote:
Originally Posted by G6Tanuki
Carbon-film resistors do, however, generally produce less thermal noise which is why they're popular in low-signal-level amplification.
No, carbon film resistors generate exactly the same thermal noise as any other resistor (including CC). What is different is the excess noise. CC are worst, CF better, metal film and wirewound best.

Quote:
Originally Posted by SteveCG
IF stages, centred on 45 Mc/s, used in Radio Astronomy in the 1970s always used CC resistors for just the low inductance point G8HQP mentioned.
The inductance of a film resistor is rarely a problem below VHF. I could imagine that at 45MHz you might not want to put a film resistor as an unbypassed cathode/emitter resistor as it might increase input impedance but for most purpose they would be fine.
G8HQP Dave is offline