Help me selecet L&C and N for IF amplifier design
时间：04-08
整理：3721RD
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Hello All,
I'm trying to build a multistage (3 stages) 455KHz IF amplifier. The circuit is a common emitter with primary tuned transformer on the collector. I can not get IF transformers so I have to build them by my self. I have a big problem to design the transformer as follows:
1) What L & C should I use for the primary side for 455KHz?
2) What L should I use for the secandary side?if the next stage input impedance is 3.3K for example.
3) What is the turns ratio should I use? if the next stage input impedance is 3.3K for example.
I realy have seriose problem with selection of L&C and N. Any help is greatly appreciated.
I'm trying to build a multistage (3 stages) 455KHz IF amplifier. The circuit is a common emitter with primary tuned transformer on the collector. I can not get IF transformers so I have to build them by my self. I have a big problem to design the transformer as follows:
1) What L & C should I use for the primary side for 455KHz?
2) What L should I use for the secandary side?if the next stage input impedance is 3.3K for example.
3) What is the turns ratio should I use? if the next stage input impedance is 3.3K for example.
I realy have seriose problem with selection of L&C and N. Any help is greatly appreciated.
http://www.lulu.com/items/volume_65/...nt/7219361.pdf
If you get an old 8x8x12 mm ferrite can from Toko or Murata, use 70 turns and 1nF capacitor to resonate on 455 kHz. Secondary generally is 1/10 of primary (7 turns in this case).