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#41
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how do I measure S/N?
Don wrote:
In article 6Rsnc.57945$Ik.4388638@attbi_s53, says... "Don" wrote in message news:Fbinc.8757$iF6.981550@attbi_s02... I'm the original poster. Thanks to every responder for all your help. I don't have a VTVM, but I do have a Fluke 8600a DVM with an input impedance of 1000 megohms. : ) in the 200 millivolt range. -Don That's on the DC ranges. On the AC ranges the input impedance is 2 Megohms. Norm Strong See, I really am a newbie. Or sleep deprived. Anyways, I assume the Fluke is ok to measure these voltages, lacking a VTVM. YES! VTVMs were the logical predecessors of the DVM. At least I knew the issue was one of impedance. Actually, not. It's a matter of voltage. |
#42
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how do I measure S/N?
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it?
Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Arny Krueger" wrote in message ... Don wrote: In article 6Rsnc.57945$Ik.4388638@attbi_s53, says... "Don" wrote in message news:Fbinc.8757$iF6.981550@attbi_s02... I'm the original poster. Thanks to every responder for all your help. I don't have a VTVM, but I do have a Fluke 8600a DVM with an input impedance of 1000 megohms. : ) in the 200 millivolt range. -Don That's on the DC ranges. On the AC ranges the input impedance is 2 Megohms. Norm Strong See, I really am a newbie. Or sleep deprived. Anyways, I assume the Fluke is ok to measure these voltages, lacking a VTVM. YES! VTVMs were the logical predecessors of the DVM. At least I knew the issue was one of impedance. Actually, not. It's a matter of voltage. |
#43
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how do I measure S/N?
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it?
Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Arny Krueger" wrote in message ... Don wrote: In article 6Rsnc.57945$Ik.4388638@attbi_s53, says... "Don" wrote in message news:Fbinc.8757$iF6.981550@attbi_s02... I'm the original poster. Thanks to every responder for all your help. I don't have a VTVM, but I do have a Fluke 8600a DVM with an input impedance of 1000 megohms. : ) in the 200 millivolt range. -Don That's on the DC ranges. On the AC ranges the input impedance is 2 Megohms. Norm Strong See, I really am a newbie. Or sleep deprived. Anyways, I assume the Fluke is ok to measure these voltages, lacking a VTVM. YES! VTVMs were the logical predecessors of the DVM. At least I knew the issue was one of impedance. Actually, not. It's a matter of voltage. |
#44
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how do I measure S/N?
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it?
Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Arny Krueger" wrote in message ... Don wrote: In article 6Rsnc.57945$Ik.4388638@attbi_s53, says... "Don" wrote in message news:Fbinc.8757$iF6.981550@attbi_s02... I'm the original poster. Thanks to every responder for all your help. I don't have a VTVM, but I do have a Fluke 8600a DVM with an input impedance of 1000 megohms. : ) in the 200 millivolt range. -Don That's on the DC ranges. On the AC ranges the input impedance is 2 Megohms. Norm Strong See, I really am a newbie. Or sleep deprived. Anyways, I assume the Fluke is ok to measure these voltages, lacking a VTVM. YES! VTVMs were the logical predecessors of the DVM. At least I knew the issue was one of impedance. Actually, not. It's a matter of voltage. |
#45
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how do I measure S/N?
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it?
Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Arny Krueger" wrote in message ... Don wrote: In article 6Rsnc.57945$Ik.4388638@attbi_s53, says... "Don" wrote in message news:Fbinc.8757$iF6.981550@attbi_s02... I'm the original poster. Thanks to every responder for all your help. I don't have a VTVM, but I do have a Fluke 8600a DVM with an input impedance of 1000 megohms. : ) in the 200 millivolt range. -Don That's on the DC ranges. On the AC ranges the input impedance is 2 Megohms. Norm Strong See, I really am a newbie. Or sleep deprived. Anyways, I assume the Fluke is ok to measure these voltages, lacking a VTVM. YES! VTVMs were the logical predecessors of the DVM. At least I knew the issue was one of impedance. Actually, not. It's a matter of voltage. |
#46
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how do I measure S/N?
Mark D. Zacharias wrote:
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. |
#47
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how do I measure S/N?
Mark D. Zacharias wrote:
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. |
#48
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how do I measure S/N?
Mark D. Zacharias wrote:
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. |
#49
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how do I measure S/N?
Mark D. Zacharias wrote:
Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. |
#50
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how do I measure S/N?
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? TonyP. |
#51
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how do I measure S/N?
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? TonyP. |
#52
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how do I measure S/N?
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? TonyP. |
#53
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how do I measure S/N?
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? TonyP. |
#54
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. http://www.atecorp.com/Equipment/Fluke/8600A.htm I suppose that is something like the residual it reads when driven with a low impedance source. This seems sufficient to make SNR measurements that would show progress made on a phono preamp design. The fact that it is not true rms says that any measurements made are going to be nonstandard, but it seems like they could be helpful to a home constructor. |
#55
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. http://www.atecorp.com/Equipment/Fluke/8600A.htm I suppose that is something like the residual it reads when driven with a low impedance source. This seems sufficient to make SNR measurements that would show progress made on a phono preamp design. The fact that it is not true rms says that any measurements made are going to be nonstandard, but it seems like they could be helpful to a home constructor. |
#56
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. http://www.atecorp.com/Equipment/Fluke/8600A.htm I suppose that is something like the residual it reads when driven with a low impedance source. This seems sufficient to make SNR measurements that would show progress made on a phono preamp design. The fact that it is not true rms says that any measurements made are going to be nonstandard, but it seems like they could be helpful to a home constructor. |
#57
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. http://www.atecorp.com/Equipment/Fluke/8600A.htm I suppose that is something like the residual it reads when driven with a low impedance source. This seems sufficient to make SNR measurements that would show progress made on a phono preamp design. The fact that it is not true rms says that any measurements made are going to be nonstandard, but it seems like they could be helpful to a home constructor. |
#58
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how do I measure S/N?
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#59
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how do I measure S/N?
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#61
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how do I measure S/N?
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#62
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how do I measure S/N?
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. Rectifier linearity is an issue. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. TonyP. |
#63
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how do I measure S/N?
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. Rectifier linearity is an issue. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. TonyP. |
#64
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how do I measure S/N?
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. Rectifier linearity is an issue. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. TonyP. |
#65
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how do I measure S/N?
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. Rectifier linearity is an issue. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. TonyP. |
#66
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. True in general, but modern meters use precision rectifiers that are IME really quite good. Rectifier linearity is an issue. These multimeters also have amplfiiers that front-end the AC converters. These meters are usually quite linear, with internal noise being more of a problem at the low end. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. Agreed. |
#67
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. True in general, but modern meters use precision rectifiers that are IME really quite good. Rectifier linearity is an issue. These multimeters also have amplfiiers that front-end the AC converters. These meters are usually quite linear, with internal noise being more of a problem at the low end. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. Agreed. |
#68
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. True in general, but modern meters use precision rectifiers that are IME really quite good. Rectifier linearity is an issue. These multimeters also have amplfiiers that front-end the AC converters. These meters are usually quite linear, with internal noise being more of a problem at the low end. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. Agreed. |
#69
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how do I measure S/N?
TonyP wrote:
"Arny Krueger" wrote in message news TonyP wrote: "Arny Krueger" wrote in message ... Mark D. Zacharias wrote: Not an expert on Fluke's, but the 77 anyway wasn't a true RMS meter, was it? No, the Fluke 77 series was/is not a true RMS meter. I think that you have to go up into Fluke's 80 series to get that feature. It really doesn't matter whether it's true RMS or not considering few DVM's, including Fluke 70 or 80 series, can measure AC signals below 1 mV anyway (or a *long* way above 1mV with any precision for that matter). Just *HOW* noisy is that pre-amp????????? Right. Most audio gear has maximum useful output between 1 and 2 volts. The OPs Fluke 8600 spec says that it resolves 10uV on the 200 mv range. I imagine that is the least signficiant digit on the most sensitive range. It's a 4 1/2 digit meter. Yes, the 8600 will be much more useful than the 70 or 80 series hand helds mentioned by Mark. However the resolution at higher values is not the same as the precision at low values. True in general, but modern meters use precision rectifiers that are IME really quite good. Rectifier linearity is an issue. These multimeters also have amplfiiers that front-end the AC converters. These meters are usually quite linear, with internal noise being more of a problem at the low end. Having said that, for the simple better or worse comparison needed, it doesn't matter about RMS vs Average responding or the actual measurement uncertainty, provided the input is similar in both cases. Agreed. |
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