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#31
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![]() "Ralph Mowery" wrote in message k.net... Chances are there is nothing wrong with either system. Operating 15 kcs is really too close for repeaters. Many of them are converted comercial rigs and the selectivity is not that good in many cases as they were designed for 30 KC spacings. When the repeater keys up and you are 15 kc away from it , will it break the squelch of your rig ? No. As a matter of fact, I tried to hear several VERY close repeaters when +/- 15kc of their outputs. I heard none of them. You're telling me a repeater is *supposed* to be *less* selective than a Kenwood TM-271A? P.S. Happy Thanksgiving. 73's es gd trky de Ken KG0WX |
#32
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In article t,
Ralph Mowery wrote: Chances are there is nothing wrong with either system. Operating 15 kcs is really too close for repeaters. Many of them are converted comercial rigs and the selectivity is not that good in many cases as they were designed for 30 KC spacings. Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. It'd be nice to be able to count on 30 kHz repeater spacing, but in many areas of the country the 2-meter repeater subbands are just too crowded to permit this. -- 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! |
#33
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In article t,
Ralph Mowery wrote: Chances are there is nothing wrong with either system. Operating 15 kcs is really too close for repeaters. Many of them are converted comercial rigs and the selectivity is not that good in many cases as they were designed for 30 KC spacings. Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. It'd be nice to be able to count on 30 kHz repeater spacing, but in many areas of the country the 2-meter repeater subbands are just too crowded to permit this. -- 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! |
#34
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In article t,
Ralph Mowery wrote: Chances are there is nothing wrong with either system. Operating 15 kcs is really too close for repeaters. Many of them are converted comercial rigs and the selectivity is not that good in many cases as they were designed for 30 KC spacings. Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. It'd be nice to be able to count on 30 kHz repeater spacing, but in many areas of the country the 2-meter repeater subbands are just too crowded to permit this. -- 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! |
#35
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![]() No. As a matter of fact, I tried to hear several VERY close repeaters when +/- 15kc of their outputs. I heard none of them. You're telling me a repeater is *supposed* to be *less* selective than a Kenwood TM-271A? I am not saying the repeater is suspost to be less slective, just that many are. Some (maybe alot ) of repeaters are converted from older comercial gear such as the GE Mastr ll series. They probably are not as selective. They met the comercial standards from 20 or so years ago. While there are probably not very many if any of the old VHF Enginering units in use today, they were fine repeaters for the money and for what was out about 25 or so years ago. I still put one on about 2 years ago while I took the other repeater off the air to do some work for a week or so. While your Kenwood may be more selective than the repeater , try keying the thing for an hour or two in a shack that is about 100 deg F . The repeater has to be built to a differant enviroment than the rigs at home operate in. It might also have a 20 db preamp on it and the deviation may be lower. I am not defending the repeater over your rig, just mentioning some things that the repeater owners have to compete with. Also look at the overall cost of the repeater, including the antenna and controler and duplexer. By the time some of the other items have been bought it may leave little money for the actual receiver and transmitter. |
#36
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![]() No. As a matter of fact, I tried to hear several VERY close repeaters when +/- 15kc of their outputs. I heard none of them. You're telling me a repeater is *supposed* to be *less* selective than a Kenwood TM-271A? I am not saying the repeater is suspost to be less slective, just that many are. Some (maybe alot ) of repeaters are converted from older comercial gear such as the GE Mastr ll series. They probably are not as selective. They met the comercial standards from 20 or so years ago. While there are probably not very many if any of the old VHF Enginering units in use today, they were fine repeaters for the money and for what was out about 25 or so years ago. I still put one on about 2 years ago while I took the other repeater off the air to do some work for a week or so. While your Kenwood may be more selective than the repeater , try keying the thing for an hour or two in a shack that is about 100 deg F . The repeater has to be built to a differant enviroment than the rigs at home operate in. It might also have a 20 db preamp on it and the deviation may be lower. I am not defending the repeater over your rig, just mentioning some things that the repeater owners have to compete with. Also look at the overall cost of the repeater, including the antenna and controler and duplexer. By the time some of the other items have been bought it may leave little money for the actual receiver and transmitter. |
#37
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![]() No. As a matter of fact, I tried to hear several VERY close repeaters when +/- 15kc of their outputs. I heard none of them. You're telling me a repeater is *supposed* to be *less* selective than a Kenwood TM-271A? I am not saying the repeater is suspost to be less slective, just that many are. Some (maybe alot ) of repeaters are converted from older comercial gear such as the GE Mastr ll series. They probably are not as selective. They met the comercial standards from 20 or so years ago. While there are probably not very many if any of the old VHF Enginering units in use today, they were fine repeaters for the money and for what was out about 25 or so years ago. I still put one on about 2 years ago while I took the other repeater off the air to do some work for a week or so. While your Kenwood may be more selective than the repeater , try keying the thing for an hour or two in a shack that is about 100 deg F . The repeater has to be built to a differant enviroment than the rigs at home operate in. It might also have a 20 db preamp on it and the deviation may be lower. I am not defending the repeater over your rig, just mentioning some things that the repeater owners have to compete with. Also look at the overall cost of the repeater, including the antenna and controler and duplexer. By the time some of the other items have been bought it may leave little money for the actual receiver and transmitter. |
#38
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![]() Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. That's nice that your group can put the Kendecom repeaters on the air. In some areas there is not that much money for the whole system let alone just for the repeater. |
#39
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![]() Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. That's nice that your group can put the Kendecom repeaters on the air. In some areas there is not that much money for the whole system let alone just for the repeater. |
#40
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![]() Here in northern California, repeater spacings in the 2-meter band seem to be about evenly divided between 15 kHz and 20 kHz, depending on which portion of the band one is taking about. The local repeater coordination council (NARCC) mandates the use of narrow-selectivity RF and IF stages, and peak transmit deviations not to exceed 4 kHz. The new Kendecom repeaters my group is in the process of putting on the air, have an IF response which falls off of a cliff at 7.5 khz... in fact these rigs are very prone to pop or squelch if somebody's radio is tuned up too hot and is over-deviating past this point. That's nice that your group can put the Kendecom repeaters on the air. In some areas there is not that much money for the whole system let alone just for the repeater. |
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