SO2R on 6700 vs 6600M

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  • Updated 2 months ago
As far as I understand that  6700 doesn't need additional filters for SO2R. All filters are inside 6700.
What about 6600M? Is it configured like 6700 or do we need provide external filter?
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Wlodzimierz Tomczyk

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Posted 2 months ago

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Steven Linley

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Includes all filters for contesting bands
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Bill English

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I understand the 6600's also have the filters for SO2R. I understand that with higher power, SO2R was only possible the AG amp from Flex without additional filters, They also mentioned that if your antennas are close together you may have to use external filters anyway, even with the Flex amp. Like they said, every situation is different.
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Chris Tate - N6WM, Elmer

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Well, this really depends on your antenna separation and power levels.  For instance, the 6600 and its 7th order preselectors helped some remove their in line bpf's and achieve adequate isolation as compared to the 6700.  but if your antenna proximity and power levels are enough to overload the ports still, you will still need to use filters in (low power in the feeds to the amp, including PG, and/or high power filters on the outputs to the antennas in an SO2R(TX while listening) environment.  also worth noting, no bpf will protect from phase noise on the fundamental..  

In summary, the 6600 7th order preselectors help, but with both the 6700 and 6600, you still may need to plan to use external filter methods for additional isolation depending on your particular environment.
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Mack McCormick, Elmer

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I have the 6600 and 6700 in my shack. The 6600 has great filtering and I do not need to use external filters. With the 6700 I DO need to use external contest filters for isolation. The internal 6700 filters are not as brickwall as the 6600.

Mack
W4AX
Alpha Team
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Chris Tate - N6WM, Elmer

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Right.  As I said, some (including you ;-))were able to achieve the needed isolation with the 6600 7th order isolation filters.  It really depends on the environment, antenna separation etc.
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Ria - N2RJ, Elmer

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Mack - how far apart are your antennas? I have two on one tower and the others are about 80-150ft apart. Btw polarization matters. It’s the most understated thing about SO2R isolation.
(Edited)
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Chris DL5NAM

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... i have 3 monobander on one boom (3 coax cable) - bring me a 6600 i will do a test ;-)
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Ria - N2RJ, Elmer

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External filters or stubs are beneficial. K9CT ran some tests and with his antenna separation he was able to remove his BPFs. But others in close proximity won’t be able to, so BPFs are a must. They also help on transmit, which the 6600’s or 6700’s do not do.
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Chris Tate - N6WM, Elmer

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correct.
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Ria - N2RJ, Elmer

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I strongly recommend W2JVN’s book.

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