开云体育Wrong thread? ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? ? email:? bill@... ? From: [email protected] [mailto:[email protected]] On Behalf Of Leland Lannoye
Sent: Monday, January 22, 2018 10:30 PM To: [email protected] Subject: Re: [BITX20] #ubitx and 6 meters ? Bill: Why not use a bridge rectifier to keep the correct polarity regardless of input polarity hook up?? I realize this causes a volt drop of up to 1.4 volts. The relay circuit I saw might be better in that regard, however, I? don't? like relays always on. ? ? ? Sent from my Verizon, Samsung Galaxy smartphone ? -------- Original message -------- From: K9HZ <bill@...> Date: 1/22/18 21:20 (GMT-05:00) Subject: Re: [BITX20] #ubitx and 6 meters ? Yeah yeah everyone and their brother makes a converter from X to 50 MHz but I think the idea is to use something that works without a converter.? Let the experimentation begin! ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? ? email:? bill@... ? From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan ? 50 MHz is a problem simply because the IF is at 45 MHz, very close to 50 MHz. Instead, you can try a converter. An ADE-1 (or a diode mixer made with 1N4148s) fed by a single 2N3904 as an oscillator at 27 or MHz should bring in a lot of local signals. The converter will output at 50-27 = 23 MHz. You can make do with a doubly tuned circuit in the front-end. A pair of bidirectional RF amplfiers, exactly similar to what the ubtix uses will prop up the noise figure and over come the? band pass filter losses. ? - f ? ? On Sun, Jan 21, 2018 at 11:51 PM, Tom Christian <tmchristian@...> wrote:
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