2006年4月14日 · Tuning the BFO frequency and using a spectrum analyzer or a selective receiver on pin 4 of U2, verify the rejection of the unwanted sideband (SSB signal). Ideal rejections for carrier and for unwanted sideband should be better than 40dB. MC1496 can get up to 60dB carrier suppression when NE612 can get maximum 30dB.

30 m Band Direct Conversion Receiver. The direct conversion receiver described consists of only a bandpass filter, mixer IC, VFO and audio filter. With only 22 parts, this simple circuit should take a few hours at the weekend to construct. For extra simplicity, eliminate L1 & C1 and connect C2 to the slider of P1. Fig. 1: Schematic of the receiver.

2014年1月27日 · This time I investigated the properties of direct conversion receivers using the cheap and widely available NE612 balanced mixer IC. There are four different versions of this c...

2020年1月22日 · Thus a low valued capacitor has been inserted prior to the SSB filter, sited on the RX board. After that we see an amplifier with limited gain due to high emitter degeneration and the NE612 as TX mixer.

2020年1月13日 · The NE612 is an integrated circuit which contains a balanced mixer with its own on-board local oscillator and voltage regulator. The mixer can provide up to 18dB of gain at 45 Mhz, and the local oscillator will operate up to 200 Mhz.

The concept of the RX converter is quite simple and nothing really new. The local oscillator is a standard colpitts crystal oscillator producing the 22MHz LO signal. This signal is fed into the traditional NE612 double balanced mixer from Philips. …

2019年4月5日 · You know neophyte receiver on QST ham radio rx: mini,using ne612. The details are on my site, "RADIO KITS IN JA"

Receiver description a single conversion super heterodyne reeiver. The RF front end section comprising TR1,TR2,C31,C32, & C33 forming a three element Pi band pass filter impedance matched to both the antenna and first mixer IC2 (NE612). Although there is no RF pre-amplifier, the mixer IC2 does provide around 8db conversion of gain.

2008年10月2日 · The NE612 is an integrated circuit which contains a balanced mixer with its own on-board local oscillator and voltage regulator. The mixer can provide up to 18dB of gain at 45 Mhz, and the local oscillator will operate up to 200 Mhz.

The NE/SA612A is a low-power VHF monolithic double-balanced mixer with on-board oscillator and voltage regulator. It is intended for low cost, low power communication systems with signal frequencies to 500MHz and local oscillator frequencies as high as 200MHz.