Force 300csm PTP mode

Hi all, would a Force 300csm with Canadian country code be able to go into PTP mode? Not finding much info…

Yes it will work. Just set one of them as AP and secound as SM. Thats all.

PTP mode or are you talking TDD mode?

U can use TDD or ePTP mode. Just choose it on AP. SM will choose it directly from AP.

Oh okay, Im being told by my regional cambium dealer that it is not able to be used in ptp mode.

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I found an issue in 4.6 that the force300csm does not connect to ptp-tdd until the AP is set to just tdd mode. to make it a ptp link, set the single valid SM mac on the AP and the preferred AP in the SM.

I am posting this issue to the 4.6-known-issues too

Oh I see, what kind of distance would I be able to get if both ends are 2ft 30db dish? I was told by cambium and regional rep that the force 300csm does not have ptp mode, which you have confimed can relatively be done. Thank you!

The force300csm does not have ptp mode (which is odd since thats one of the best uses of it)
Regarding your link distance question(warning, long!):

It is less the physical antenna but more the link budget and the losses which determines the distance.
Using a 3000L and a force300csm on 5825Mhz max tx power Canada is 23dBm and both recievers are -90 sensitive and your 30db antennas you will have 23+90+30+30=286dB of budget. The question is the losses. I have a 7.8mile link with excessive losses of 113dB and another that is only 85dB losses with similar link distance. Path makes everything!

What this comes down to is if your asking how far can I get with this setup then you haven’t engineered the link and are guessing, which is going to make either expensive, poor performing or both links.

What I start with is I figure out the link distance required and the heights available on both ends. Then I figure out the minimal height needed on each end to support the link above the curve of the earth plus some vegetation growth room. Once this is done, I select the radios that I will be using based on capacity required, growth of link capacity, RX sensitivity and TX power per region in this order. This will also set the base budget requirements as now your software (Link planner does good for this, just use whatever antenna you want as it is not important at this stage) can pull a profile and show you how much gain is needed for that link to meet your throughput requirements at the determined RX levels. Some software will show you the one-way link gain required (Link planner) and some will show you the total system gain required. If you find you need an additional 12dB of gain to meet your throughput requirements using Link Planner and you have the force300-25 selected, then add 25 to 12 and that is the antenna gain you need to look at. And in this example, 39dB dish would be about 5ft in diameter and heavy, so now you need to calc the wind loading and determine if you need to re-enforce the support structure, use a wind deflecting cover, if a mesh dish (with poor f/b ratio) is acceptable and even if the aesthetics of such antenna is acceptable. And remember that IF you can go higher, which you can do to reduce the amount of losses due to ground skimming the path, your support structure may limit your size of antenna without re-enforcement.
Remember that you can also add another hop (and no it doesnt have to be a direct path) to get a better path and thus better speeds. Yes it will cost more, but is usually less than the excessive antenna sizes required for some links.

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Thank you for your reply… I will get a link planner done on this. Appreciate your answer, with the max tx being at 23, what is the max eirp? Link planner lets me know that correct?

Max EIRP is determined by your regulatory board. In Canada (where I am) for PTP links, according to RSS-210, Annex 8 and 9, the limit is what it takes to make the link with in mind safety code 6 and respecting the conducted power limit for the frequency used. Link Planner will NOT show you this as you are supposed to be conversant with the regulations.

The 23dB limit is Cambium applying FCC rules and limits to Canada (which for the most part are the same however there are important differences with respect to PTP links) and thus it is what most of us will see as the TX power limit. ETSI regions are on their own, sorry but I gave up trying to figure that mess out!

Okay, thank you… I just remember reading for canada the max eirp for ptp in, ie 5825, is 53. I apologize if I am misinformed.

That is the old (very old) rules for 802.11a systems.

Sign up for the Gazette on the ised website. It will let you know when things change. Else follow rss-210 and the annex list. Also you can safely ignore channel/power lists off the internet unless you fall into the specific use categories that they are for. Eg. Inside vs outside, ptp vs pmp, conducted power vs eirp limited bands.

It can be a maze to sort out but if you know the rss, it will tell you what you need to know and the annexs tell you what changes have been made.