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#1
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hi,
i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? thanks in advance, john |
#2
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No it won't. Short of ergonomics you have the best one IMO.
Frank K3YAZ john wrote: hi, i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? thanks in advance, john |
#3
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In article . com,
"john" wrote: hi, i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? The R8B is a much better upgrade than the R8A. The B version has sideband selectable sync. Mike |
#4
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Would some of you receiver experts that lurk here please explain to me
why the selectable SYNC on the R8B is any differient than using the PBT while in SYNC on the R8A. Now a receiver that had a limited PBT range ie.. JRC I can see that it would not give true USB/LSB shift. But on the R8A the PBT will cover more than the 3khz bandwith on each side band. Take 5.070 mhz now at 02:18 utc. There is a a pinging sound on the USB side but not on the LSB. I engage the SYNC in AM mode 6khz filter & I hear the ping with the PBT set to 12:00 oclock setting. If I slide it slowly to the Left or the LSB I do not hear the Ping. If I shift the PBT to the right or the USB & the ping is there. Is this not the same as selecting USB or LSB on the R8B SYNC ????? 73, Ken Mike wrote: In article . com, "john" wrote: hi, i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? The R8B is a much better upgrade than the R8A. The B version has sideband selectable sync. Mike |
#5
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The R8A (like the B model) has more memory and MUCH better computer control
capability than the older R8. In fact, some control programs do not support the R8, just the A or B. -- Brian Denley http://home.comcast.net/~b.denley/index.html "john" wrote in message ups.com... hi, i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? thanks in advance, john |
#6
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Ken Wilson wrote:
Would some of you receiver experts that lurk here please explain to me why the selectable SYNC on the R8B is any differient than using the PBT while in SYNC on the R8A. Now a receiver that had a limited PBT range ie.. JRC I can see that it would not give true USB/LSB shift. But on the R8A the PBT will cover more than the 3khz bandwith on each side band. Take 5.070 mhz now at 02:18 utc. There is a a pinging sound on the USB side but not on the LSB. I engage the SYNC in AM mode 6khz filter & I hear the ping with the PBT set to 12:00 oclock setting. If I slide it slowly to the Left or the LSB I do not hear the Ping. If I shift the PBT to the right or the USB & the ping is there. Is this not the same as selecting USB or LSB on the R8B SYNC ????? 73, Ken With PBT, the ability to attenuate the unwanted sideband is limited by the skirt selectivity characteristics of the filter. With selectable sideband sync detectors, the unwanted sideband is cancelled by the circuitry. This can be significant if the detector is well tuned. The two are not the same. |
#7
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craigm ) writes:
With PBT, the ability to attenuate the unwanted sideband is limited by the skirt selectivity characteristics of the filter. With selectable sideband sync detectors, the unwanted sideband is cancelled by the circuitry. This can be significant if the detector is well tuned. But of course, how much a phasing type circuit attenuates the unwanted sideband is a reflection of how precise the components are, and how well balanced the circuit is. And one reality is that "sync detectors" came into common use in relatively low end receivers. Before the Sony 2010, I can't think of any receiver that had a built in sync detector. The advantage in that and other low end receivers is that it does allow "narrowing" the selectivity without the cost of a filter. It is cheaper to use some passive components and an IC than to add a good IF filter. To make a fair comparison, one actually has to compare the receivers, rather than compare techniques. Because while passband tuning does indeed reflect on the skirts of the filters used, phasing-based selectible sideband depends on the components and circuitry used. Once you start paying for a receiver out of the portable category, chances go up that the filters are better than run of the mill ceramic filters, which means their passband tuning may be fine. (And I actually can't think of an instance of passband tuning in a cheap receiver.) On the other hand, there are lots of relatively inexpensive receivers with not so great ceramic filters that do use the phasing method to get selectible sideband, and since those are lower cost receivers, one might wonder how good the phasing networks are. Fifty years ago, people would buy phasing type SSB adaptors for their receivers. They wanted an actual product detector, rather than the "envelope detector" that came in their receiver, because SSB was coming in and they wanted to adapt. The selectivity of the receivers were often limited, because they'd been intended for AM reception. So an ssb adaptor with the phasing method allowed for improved selectivity with relatively low cast and no need to modify the receiver (other than adding a point to connect the adaptor). But nobody claimed this was better than a good IF filter in the receiver. Michael |
#8
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In article . com,
"Ken Wilson" wrote: Mike wrote: In article . com, "john" wrote: hi, i recently purchased an very nice drake r8 my choice over the icom r75 - i don't regret my decision one bit - a great radio and along with my palstar one of the best i have owned and i have owned a few. my question is will an r8a buy me much more in terms of better DX and audio, sync detection etc. i have heard the build quality is a bit better on the r8 and also uses the original drake decoder that was used in the R7. besides these things, will the r8a buy me much more? The R8B is a much better upgrade than the R8A. The B version has sideband selectable sync. Would some of you receiver experts that lurk here please explain to me why the selectable SYNC on the R8B is any differient than using the PBT while in SYNC on the R8A. Now a receiver that had a limited PBT range ie.. JRC I can see that it would not give true USB/LSB shift. But on the R8A the PBT will cover more than the 3khz bandwith on each side band. Take 5.070 mhz now at 02:18 utc. There is a a pinging sound on the USB side but not on the LSB. I engage the SYNC in AM mode 6khz filter & I hear the ping with the PBT set to 12:00 oclock setting. If I slide it slowly to the Left or the LSB I do not hear the Ping. If I shift the PBT to the right or the USB & the ping is there. Is this not the same as selecting USB or LSB on the R8B SYNC ????? PBT is similar in result to using side band selectable sync but the sync is generally more effective. -- Telamon Ventura, California |
#9
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OK Thanks for the Info.
When the unwanted sideband is cancelled by the circuitry how do you get the 6khz bandwidth instead of 3khz.Or maybe you don't ???? I am talking/asking about the Drake R8A vs R8B receivers only... with the bandwidth set to 6khz & AM SYNC mode. Learning all the time. 73, Ken craigm wrote: With PBT, the ability to attenuate the unwanted sideband is limited by the skirt selectivity characteristics of the filter. With selectable sideband sync detectors, the unwanted sideband is cancelled by the circuitry. This can be significant if the detector is well tuned. The two are not the same. |
#10
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In article . com,
"Ken Wilson" wrote: With PBT, the ability to attenuate the unwanted sideband is limited by the skirt selectivity characteristics of the filter. With selectable sideband sync detectors, the unwanted sideband is cancelled by the circuitry. This can be significant if the detector is well tuned. The two are not the same. OK Thanks for the Info. When the unwanted sideband is cancelled by the circuitry how do you get the 6khz bandwidth instead of 3khz.Or maybe you don't ???? I am talking/asking about the Drake R8A vs R8B receivers only... with the bandwidth set to 6khz & AM SYNC mode. Learning all the time. In AM mode, listening to an AM station and with the PBT control at 12 o'clock using the 6KHz filter you have 3 KHz of the lower and 3KHz of the upper side bands. Rotate the PBT control to 3 o'clock and you have 6 KHz of the upper side band and none of the lower side band. You get the reverse situation when you turn the PBT to 9 o'clock. The high modulated frequencies are farther from the carrier so you will hear an improvement in the audio high end when the PBT control is turned either way from the 12 o'clock position. -- Telamon Ventura, California |