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Please Support Our Advertisers Product Review MFJ-1020B Indoor Active SWL Antenna I've been into HF monitoring since 1976 and love it. When living at my parents in Bedford County, PA we had the room for a nice longwire. I had a 180' longwire antenna tied to my radios and boy was it great. When I moved to Reading, PA (this town sucks!, I'm sorry, I call them as I see them!) I lived in a one bed room apartment. The only good thing was it was on the third floor. Using a random wire along the baseboard did pretty nicely, but it wasn't like my 180' wire back home. Well now I live in a townhome in Lancaster, PA and the same story, can't have an outdoor antenna! And no attic! So once again I took 30 gauge wire and taped it to the wall around my radio room. I had the room to do a 40 and 20 meter dipoles (ok there is a bend in each leg, but it works!). This setup has been working good, but one day I thought I would try an active antenna. Everytime I asked on the Newsgroups which one to buy I would get a million different answers. MOST answers where (I'm paraphrasing here)"don't do it they just pick up noise". Well after surfing the net I found the MFJ-1020B. I remember many years ago seeing this in catalogs and magazines.  I looked on the on-line auctions but couldn't find one (oh, by the way, please check out my eBay & Scanners editorial when you're done reading here. Ok, back to my story....Here's what their manual say's: The MFJ-1020B Active Antenna provides reception of radio signals without an outside antenna. The MFJ-1020B receives from 300KHz to 30MHz which includes all international short-wave and HF bands. This antenna also functions as a pre-selector for inside and outside wire antennas through the use of FET and bipolar circuitry with a tuned input section. The tuned circuit in the Active Antenna gives RF selectivity and reduces noise outside the tuned band. This circuit can be bypassed without disconnecting the unit by using the On/Off Bypass switch. Use a 9V battery and the telescoping antenna for portable operation. That's what the manual says..... Ok, to sum up my feelings....I love the thing! It comes in a nice metal case. SO-239 and RCA phone jacks are provided for both antenna inputs and output to the receiver. Also on the back panel is a heavy duty grounding post. I haven't used mine with a 9V battery, I simply bought a RadioShack 9V power supply which works fine and doesn't produce any noise. At first I used the included telecoping antenna which produced fine results. To my surprise, the unit didn't produce any noise, a problem that many people told me I would have with nearly all active antennas. I was pulling in stations with the telescoping antenna which I could not receive on my 20 or 40 meter dipoles. So, I liked what I saw so far. Then I started feeding my dipoles through the Active Antenna by using the SO-239 connectors. WOW! Now the unit works as an amp/pre-selector. On the font panel there is a calibrated dial to set the tuner as a starting point. It is pretty accurate as I've found. Also including is a gain control. Fully counter-clock wise it appears to attenuate the signal to almost nothing. I haven't found a time where I would normally run the gain control anywhere but "full-on" (full clock-wise). I have not had any problems with oscillation with the gain set high (the manual advises this might happen). Also I have not noticed any overloading problems. I use my MFJ-1020B on an Icom R71A receiver. Also, I have not noticed any noise problems and our home is filled with light dimmers and "touch" lamps which are known RFI sources. Another strong point, in my radio room I have two computers, both Pentium 350MHz machines, and once again zero noise! (I know I'm luck about that!) In summary, I feel the MFJ-1020B Active Antenna is a great product and I wish I bought one long ago. Even if you have good antennas I feel this can act as a great pre-selector and/or amp for the weak signals. You can't go wrong for only $79.95 price tag. Have fun and happy listening.
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