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No QRM?
I recently moved and it was an emergency (family)
move. To fund the move, I had to sell my 2 mo old FT-857D. :-( Last week, I saw a possible temporary replacement. A 9/95 issue Yaesu FT-840 with FM board & original manual. Nice wouldn't do justice to this rig. Heck even the power cord still had the factory kinks in it. 99.995% mint. $250. Yoink! Got it home and I'm really impressed with the reciever except in AM mode. There, it needs the optional filter. Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! I just tuned in to 3.579 and switched my TV on - I barely heard a bit of QRM. At first I thought I might be off freq so I checked the whole rig out - AM BCB, 3.922, 3.950, CHU, WWV, Gander ATC - even CB channel 19 were dead on with maybe a 30 hz differance between AM/USB/LSB modes. Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Ken KG0WX |
Maybe it's your new QTH...I've never experienced the problems you cite.
Van, KL7TDZ "Ken Bessler" wrote in message ... I recently moved and it was an emergency (family) move. To fund the move, I had to sell my 2 mo old FT-857D. :-( Last week, I saw a possible temporary replacement. A 9/95 issue Yaesu FT-840 with FM board & original manual. Nice wouldn't do justice to this rig. Heck even the power cord still had the factory kinks in it. 99.995% mint. $250. Yoink! Got it home and I'm really impressed with the reciever except in AM mode. There, it needs the optional filter. Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! I just tuned in to 3.579 and switched my TV on - I barely heard a bit of QRM. At first I thought I might be off freq so I checked the whole rig out - AM BCB, 3.922, 3.950, CHU, WWV, Gander ATC - even CB channel 19 were dead on with maybe a 30 hz differance between AM/USB/LSB modes. Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Ken KG0WX |
Maybe it's your new QTH...I've never experienced the problems you cite.
Van, KL7TDZ "Ken Bessler" wrote in message ... I recently moved and it was an emergency (family) move. To fund the move, I had to sell my 2 mo old FT-857D. :-( Last week, I saw a possible temporary replacement. A 9/95 issue Yaesu FT-840 with FM board & original manual. Nice wouldn't do justice to this rig. Heck even the power cord still had the factory kinks in it. 99.995% mint. $250. Yoink! Got it home and I'm really impressed with the reciever except in AM mode. There, it needs the optional filter. Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! I just tuned in to 3.579 and switched my TV on - I barely heard a bit of QRM. At first I thought I might be off freq so I checked the whole rig out - AM BCB, 3.922, 3.950, CHU, WWV, Gander ATC - even CB channel 19 were dead on with maybe a 30 hz differance between AM/USB/LSB modes. Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Ken KG0WX |
Maybe it's your new QTH...I've never experienced the problems you cite.
Van, KL7TDZ "Ken Bessler" wrote in message ... I recently moved and it was an emergency (family) move. To fund the move, I had to sell my 2 mo old FT-857D. :-( Last week, I saw a possible temporary replacement. A 9/95 issue Yaesu FT-840 with FM board & original manual. Nice wouldn't do justice to this rig. Heck even the power cord still had the factory kinks in it. 99.995% mint. $250. Yoink! Got it home and I'm really impressed with the reciever except in AM mode. There, it needs the optional filter. Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! I just tuned in to 3.579 and switched my TV on - I barely heard a bit of QRM. At first I thought I might be off freq so I checked the whole rig out - AM BCB, 3.922, 3.950, CHU, WWV, Gander ATC - even CB channel 19 were dead on with maybe a 30 hz differance between AM/USB/LSB modes. Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Ken KG0WX |
Now I'll get to the point - I've had many rigs over the
years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Maybe it's your new QTH...I've never experienced the problems you cite. I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Now I'll get to the point - I've had many rigs over the
years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Maybe it's your new QTH...I've never experienced the problems you cite. I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Now I'll get to the point - I've had many rigs over the
years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Is it me or does this rig have something differant in it's design? 14.318 is absolutly quiet where with my FT-857D it was unuseable +/- 1.5kc. Maybe it's your new QTH...I've never experienced the problems you cite. I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
All of that is probably true...I was only going by his statement:
"Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM" Sounds like some type of physical change. I personally have a Panasonic 13" color tv less than 2' from my rigs, with no similar problems. Van "Dave Platt" wrote in message ... Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Keith V wrote: Maybe it's your new QTH...I've never experienced the problems you cite. Dave Platt wrote: I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). |
All of that is probably true...I was only going by his statement:
"Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM" Sounds like some type of physical change. I personally have a Panasonic 13" color tv less than 2' from my rigs, with no similar problems. Van "Dave Platt" wrote in message ... Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Keith V wrote: Maybe it's your new QTH...I've never experienced the problems you cite. Dave Platt wrote: I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). |
All of that is probably true...I was only going by his statement:
"Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM" Sounds like some type of physical change. I personally have a Panasonic 13" color tv less than 2' from my rigs, with no similar problems. Van "Dave Platt" wrote in message ... Now I'll get to the point - I've had many rigs over the years and ALL have recieved the TV colorburst QRM on 3.579 & harmonics. - All except this radio! Keith V wrote: Maybe it's your new QTH...I've never experienced the problems you cite. Dave Platt wrote: I suspect that it may have to do with shielding of the radio itself, perhaps. A radio with poor chassis shielding might tend to pick up near-field emissions directly from the TV, or colorburst leakage coupled back through the AC power lines. A radio whose chassis has good shielding, and which has good filtering on its power wiring and circuitry, would be less prone to near-field pickup and would detect only the colorburst harmonics which actually reach the antenna. I just ran a quick check here at my home QTH, and noticed something similar (and interesting). Last year, after I bought a used Ten-Tec Scout, I hooked it up to my wire dipole and used the 20-meter colorburst harmonic as a standard for trimming the frequency-display reference oscillator. The colorburst harmonic was clearly audible. However, today, when I looked for the harmonics with my Kenwood TS-2000 (on the same antenna, with the same power supply) they were rather difficult to hear, even with my color TV 15 feet away turned on. So, there may be both pickup-path differences between radios (direct pickup vs. antenna-only pickup) and QTH differences (well-shielded TVs versus leaky ones). |
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