N/2+2 is a pretty standard spec on 860 mhz and up. N represents the number in cascade from your reference. N is divided by 2 so that you get 0.5 db tolerance between actives. +2 is a constant for 860 mhz and up. The +2 part of the equation is determined by the type of equipment. With motorola it might be +1.5 on 860 and +2.0 for 1 ghz. Make sure to have pooch pads with 1 ghz motorola. They are a life saver. There is nothing wrong with adjusting the BDR boards. Thats what they are there. With Gainmaker it might be +2 for 860 and +2.5 for 1 Ghz. It is pretty common to use +2 if you have the trim equipment. If you dont then +2 will have to be adjusted.
The other specs I usually use is: no more than 2db difference between any 50 mhz span, and I make sure there is no reflection.
The return spec is usually 1.0 at first in cascade and .3 for each additional. That means you would use a reference from the node and the node would have to be an 1.0 reference to itself. At the first active it would be 1.3 and the second would be 1.6 db peak to valley.
Depending on where you are at, they might want you to rereference at the first actives on the forward, and use the node reference for the return. If this happens and your spec is N/2 +2, you would sweep the forward on the first active with your node reference. You might have to use tilt comp because of the signal difference. You know, 12db tilt at active and 8 at node. This usually happends when the system doesnt balance the nodes first or if there are trunk levels and feeder levels. If this is the case then you would be 1 over 2 on your cascade. 1 represents the forward and 2 represents the return. That would be second amp out but since you re referenced the forward, it will always be one less. If you find bad cable and you are gonna sweep past it, your cascade might look like this. 1/5. This would mean that you are one amp past the re reference amp that had bad cable feeding it. If the spec is N/2 +2, you should have 2.5 on forward and 2.2 on return. I always write the cascade like that on my sticker and paperwork. This way they know you had bad cable and they look for corresponding PDR.
I hope this helps. This is the typical guidelines that are usually established.
Re: Sweeping & BDR boards
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