# PTP 650 Single Polarity operation **URL:** \ **Category:** PTP\ **Created:** [November 24, 2015, 6:08pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718 "2015-11-24T18:08:28Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![RayS](https://d10gw3vjmzyp8.cloudfront.net/user_avatar/community.cambiumnetworks.com/rays/32/11680_2.png) [@RayS](https://community.cambiumnetworks.com/u/RayS)\ **Post date:** [November 24, 2015, 6:08pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/1 "2015-11-24T18:08:28Z")
The next firmware release (1-41) for the 650 will expose “channel control” in the GUI allowing you to easily disable either transmit port/polarity to tie into existing single polarity antennas and feedline. If you are currently using single polarity equipment and looking to upgrade  to PTP 650, now you can without replacing the antenna or feedline. This also provides a less expensive migration path allowing customers to swap out equipment now and take advantage of higher speeds and tx power and in the future, either add or replace antennas to get the maximum possible throughput using both polarities.  Check out the [Knowledge Base post HERE](https://community.cambiumnetworks.com/t/operate-ptp-650-with-single-polarity/42712). ---
**Author:** ![CambiumMike](https://d10gw3vjmzyp8.cloudfront.net/letter_avatar_proxy/v4/letter/c/7ba0ec/32.png) [@CambiumMike](https://community.cambiumnetworks.com/u/CambiumMike)\ **Post date:** [November 24, 2015, 6:51pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/2 "2015-11-24T18:51:21Z")
I have attached two slides to illustrate how easy it is to enable this functionality. **650 Single Pole operation (1-41 feature) - ** Enable Transmitter channel controls in web properties (this will expose the functionality) ![Picture1.jpg](https://d1okf4ta8xniw3.cloudfront.net/original/2X/a/af2e809f580a9740114e8b82fbe2206e761770bb.jpeg "Picture1.jpg") **Under System/configuration Activate transmitter channel(s) to be used** Once changes are submitted, they are immediately executed and do not require a reboot ![Picture2.jpg](https://d1okf4ta8xniw3.cloudfront.net/original/2X/b/b08c3e5045d50f7a29efbf5891b57db8e4e04675.jpeg "Picture2.jpg") ---
**Author:** ![Randy\_Armour](https://d10gw3vjmzyp8.cloudfront.net/letter_avatar_proxy/v4/letter/r/f9ae1b/32.png) [@Randy\_Armour](https://community.cambiumnetworks.com/u/Randy_Armour)\ **Post date:** [November 25, 2015, 7:38pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/3 "2015-11-25T19:38:00Z")
I have some PTP-650 links running in single polarity configuration now.  Also have two PTP-500 links in the same setup.  We are replacing single polarity feedhorns with dual polarity models as it is convienent to do so.   This new configuration parameter implies that connecting to a single polarity feedhorn and placing a cap over the unused PTP-650 connector may be unwise.  Does the radio firmware behave in a way that limits throughput, or create some other caveat?  Possibly splitting available transmit power between H and V connections??   I am curious how the new firmware will behave differently in our existing single polarity links. Thanks in advance... Randy Armour  ---
**Author:** ![Bruce\_Collins](https://d10gw3vjmzyp8.cloudfront.net/user_avatar/community.cambiumnetworks.com/bruce_collins/32/11547_2.png) [@Bruce\_Collins](https://community.cambiumnetworks.com/u/Bruce_Collins)\ **Post date:** [December 2, 2015, 12:40am UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/4 "2015-12-02T00:40:31Z")
We've always recommended disabling the unused transmitter when operating in a single polarity mode.  This new firmware just makes it easier to switch off the unused Tx polarity. ---
**Author:** ![ireddy](https://d10gw3vjmzyp8.cloudfront.net/letter_avatar_proxy/v4/letter/i/ce7236/32.png) [@ireddy](https://community.cambiumnetworks.com/u/ireddy)\ **Post date:** [March 8, 2018, 8:57pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/5 "2018-03-08T20:57:24Z")
Does this functionality also work with the PTP450i?  Basically is it possible to run the PTP450i in single polarity mode and, if so, is there any special configuration needed? ---
**Author:** ![CambiumMatt](https://d10gw3vjmzyp8.cloudfront.net/user_avatar/community.cambiumnetworks.com/cambiummatt/32/19821_2.png) [@CambiumMatt](https://community.cambiumnetworks.com/u/CambiumMatt)\ **Post date:** [March 12, 2018, 2:53pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/6 "2018-03-12T14:53:23Z")
Yes, this is possible on PTP 450i.  Connecting a single polarity will result in the radio operating at MIMO-A (or redundnant) modulation levels.  This results in half the throughput compared to the same modulation level in MIMO-B (or dual payload), but it will work. ---
**Author:** ![CambiumMatt](https://d10gw3vjmzyp8.cloudfront.net/user_avatar/community.cambiumnetworks.com/cambiummatt/32/19821_2.png) [@CambiumMatt](https://community.cambiumnetworks.com/u/CambiumMatt)\ **Post date:** [March 12, 2018, 2:54pm UTC](https://community.cambiumnetworks.com/t/ptp-650-single-polarity-operation/42718/7 "2018-03-12T14:54:30Z")
Note there is no "switching off" of any polarity.  The software in PTP 450i accommodates this automatically, and will adjust to the best throughput possible based on rf conditions.