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#ubitx and 6 meters
#ubitx
M Garza
I have not tried it, but I am pretty sure receive will work.? Since I only get about one watt on 10 meters, transmitting might not. Give it a try and let us know. Marco - KG5PRT? On Jan 16, 2018 6:10 PM, "Tom Christian" <tmchristian@...> wrote: Has anyone modified the ubitx to work on 6 meters?? Or would the mods be too extensive for the existing components? |
Perhaps with rd16HVF1 and with proper pinout,? one could manage. Regards MVS Sarma ? On Wed, Jan 17, 2018 at 8:57 AM, M Garza <mgarza896@...> wrote:
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M Garza
If I get some time this evening, I will give it a test.? I will also get to see how the radio handles 30 degree temps (it's in the garage). Marco - KG5PRT? On Jan 17, 2018 9:34 AM, "Tom Christian" <tmchristian@...> wrote: Thank you, Sarma! (and Marco).? Once my ubitx finally arrives, I'll follow up. |
M Garza
Hi Tom, I didn't get a chance to try it out.? It might not be until the weekend, but I will report back. Marco - KG5PRT? On Jan 17, 2018 9:07 PM, "Tom Christian" <tmchristian@...> wrote: Thanks, Marco! I'll be curious to see what you find. |
M Garza
Tom, I did some tests.? As the board is, it will not transmit much above 30mhz.? There is a 30mhz low pass filter that would have to be bypassed.? I tried 35mhz and I got 1/2 watt.? I get nothing @ 40mhz. Hope this helps Marco - KG5PRT? On Jan 18, 2018 8:31 AM, "M Garza" <mgarza896@...> wrote:
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开云体育The bigger question is why? ?Is there a constant level of drive from the two stages ahead of the PA? ?If not, there are a lot of changes needed to make it work well above 20 MHz.?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: email:??bill@... ? On Jan 20, 2018, at 10:16 PM, M Garza <mgarza896@...> wrote:
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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: Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up. |
开云体育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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开云体育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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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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Check out the Murata PX1002, a very nice 86.85mhz saw filter from Murata. On Mon, Jan 22, 2018 at 06:20 pm, K9HZ wrote: 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! |
the murata filter might leak some FM bc qrm. do you have a specsheet for it? - f On 23 Jan 2018 9:17 am, "Tom Christian" <tmchristian@...> wrote: Thanks, Jerry!? Will check out the Murata PX1002. |
开云体育Should be below the FM band in most (but not all) countries. Mike K5ESS ? From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan ? the murata filter might leak some FM bc qrm. do you have a specsheet for it? - f ? On 23 Jan 2018 9:17 am, "Tom Christian" <tmchristian@...> wrote: Thanks, Jerry!? Will check out the Murata PX1002. |
Datasheet for 86.85mhz SAW filter:??
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Here in the US, our FM broadcast band starts at 87.9mhz, at which point that SAW has 60 or 70dB of attenuation. However, if you are unlucky, there might be a local channel 6 broadcast TV station dumping on 82-88mhz,?in which case some shielding would be in order. On Tue, Jan 23, 2018 at 06:01 pm, Ashhar Farhan wrote: he murata filter might leak some FM bc qrm. do you have a specsheet for it? |