HF SIGNALS MBITX

µBITX HF SSB and CW Transceiver Kit

The µBITX is a general coverage HF SSB/CW transceiver kit with features you NEED for operating ease, convenience and versatility. It works from 3 MHz to 30 MHz, with up to 10 watts on SSB and CW with a very sensitive receiver. It features digital tuning, dual VFOs, RIT, CW Keyer and more. The µBITX is a general coverage HF SSB/CW transceiver kit with features you demand for operating ease, convenience and versatility. It features digital tuning, dual VFOs, RIT, CW Keyer and more.

It is a joy to operate. Press the tuning control to access all the features. Dual VFOs, RIT, CW speed, sideband selection. etc. are all accessible from a single menu. The transceiver automatically selects the proper sideband for you (you can override it, too).

The µBITX is an understandable radio and, hence, can also be a learning experience. The complexity is kept to a minimum so you can always repair and make changes if you so desire.

The µBITX has a carefully thought-out operator interface. The tuning knob features many menu options available with a simple push on the tuning knob. From RIT, to dual VFOs, to the keyer, and many other features are all accessible from the tuning knob by simply pushing on it. There are intelligent defaults everywhere (these are easily overridden). Example : below 10 MHz, it auto-selects LSB and vice versa. To operate CW, you just press the morse key.

Architecture The µBITX uses upconversion to the first IF of 45 MHz. This eliminates the need for a large number of band pass filters, keeping the design simple and virtually image free. The roofing filter at 45 MHz is 15 KHz wide. The signal is then down-converted to 12 MHz where a low ripple SSB filter with 8 crystals is used to provide a sparkling audio.

The transmitter has push-pull PA using two IRF510s for a clean output. The low cost IRF510s are simple and inexpensive to replace should the need ever arise.

Receiver :

• Sensitivity: a 0.2uv signal is clearly audible
• Selectivity: 2.4 KHz, low ripple SSB filter with 8 crystals
• RIT (Receiver Incremental Tuning)
• Continuous coverage from 500 KHz to 30 MHz
• Sideband selection
• Detent-less encoder tuning. Tunes with larger step rates when tuned quickly

Transmitter:

• More than 10 watts up to 10 MHz, 7 watts up to 21 MHz, 2 watts on 28 MHz
• CW transmit with the built-in keyer
• Uses IRF510s x 2 as PA and 2N3904 x 4 drivers in push-pull mode for low distortion transmission.