Stevens R. Miller
Well-Known Member
Well, once again I am baffled by something I thought would be easy to understand. My company has eight Shure SLX4 receivers, and eight SLX1 transmitters. Six of the SLXs are in band H5 and two of them are in band J3. When I got the system (on loan so I can learn how it works), all eight were already configured and synced to group/channel settings the company regularly uses without problems.
Now, Shure's User's Guide suggests that all receivers should be set to the same group within a band. As you might expect, that's not how whoever set this up did it. Only two of the H5s are in the same group and both of the J3s are in different groups.
First question I have is, why is it a good idea to put them into the same group? (Guess: the specific frequencies in a group are chosen to create intermod products that don't land on frequencies in the same group.)
Now, one needs a clear channel, of course. When I use the automatic channel finder on my second J3 when it is set to Group 3, it happily chooses Channel 5, which works fine. But, I recently discovered Shure's Wireless Frequency Finder Web site, which tells me that J3's Group 3, Channel 5, is not available. Apparently, that's because its 577.750 MHz frequency is smack in the middle of WETA-TV's television channel 31 band segment of 572-578 MHz, and that they are only ten miles away. Except that WETA is on Channel 27 (virtual channel 26), which is 548-554 MHz.
Second question, then, is why is Shure claiming I can't use Band J3, Group 3, Channel 5 when, as far as I can tell, it's in the clear?
Next, Shure's Web site lists six bands that it says are recommended for use in my area, one of which is J3. For each recommended band, it lists the number of mics I can use on the available groups and channels. For H5, for example, it says I can use Channels 8 through 12 of Group 6. I actually am using a Channel in Group 6, but it is Channel 2, which Shure says I can't use (because it is used by WMDO-LD on Channel 22). None of the rest of my H5 SLX4s are using Group 6 at all, yet all work fine. For J3, Shure says I can have zero mics on that band.
Third question: why is Shure recommending band J3 when, at the same time, it says there are no available channels for me to use in that band?
Fourth question: why is Shure telling me that WETA is on television channel 31?
All answers gratefully received, with dubious and uninsured legal advice available as compensation.
Now, Shure's User's Guide suggests that all receivers should be set to the same group within a band. As you might expect, that's not how whoever set this up did it. Only two of the H5s are in the same group and both of the J3s are in different groups.
First question I have is, why is it a good idea to put them into the same group? (Guess: the specific frequencies in a group are chosen to create intermod products that don't land on frequencies in the same group.)
Now, one needs a clear channel, of course. When I use the automatic channel finder on my second J3 when it is set to Group 3, it happily chooses Channel 5, which works fine. But, I recently discovered Shure's Wireless Frequency Finder Web site, which tells me that J3's Group 3, Channel 5, is not available. Apparently, that's because its 577.750 MHz frequency is smack in the middle of WETA-TV's television channel 31 band segment of 572-578 MHz, and that they are only ten miles away. Except that WETA is on Channel 27 (virtual channel 26), which is 548-554 MHz.
Second question, then, is why is Shure claiming I can't use Band J3, Group 3, Channel 5 when, as far as I can tell, it's in the clear?
Next, Shure's Web site lists six bands that it says are recommended for use in my area, one of which is J3. For each recommended band, it lists the number of mics I can use on the available groups and channels. For H5, for example, it says I can use Channels 8 through 12 of Group 6. I actually am using a Channel in Group 6, but it is Channel 2, which Shure says I can't use (because it is used by WMDO-LD on Channel 22). None of the rest of my H5 SLX4s are using Group 6 at all, yet all work fine. For J3, Shure says I can have zero mics on that band.
Third question: why is Shure recommending band J3 when, at the same time, it says there are no available channels for me to use in that band?
Fourth question: why is Shure telling me that WETA is on television channel 31?
All answers gratefully received, with dubious and uninsured legal advice available as compensation.