BCD325P2/BCD996P2: Question for the Uniden experts or well-informed

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neilbell

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Concerning scan speeds: If you have a large large phase 1 trunked system and would like to break it into three selectable scan groups it seems like I have two choices. First put them under one system quick key with three group quick keys , or secondly, simply have them under three separate system quick keys.

The advantage of having them under one SQK means only one set of tower sites is needed but three GQKs are needed. Having them under 3 SQKs means three sets of tower sites will need to be programmed and no GQKs are needed.

Operationally separate SQKs are nicer since I find GQKs can frequently be a pain to use. So the issue: Is scanning somewhat or significantly slower with the separate SQK approach? The system I am referring to is the SF Bay Area East Bay Regional Communications System (EBRCS). There are nearly 500 talk groups and multiple towers, of which 5 or 6 can be heard from my location. A number of these are simulcast

Informed opinions and suggestions are most welcome!

Neil Bell, KJ6FBA
 

ofd8001

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Using the system quick key method is less efficient. The scanner dwells on a site for about 1-2 seconds. If no activity is present for a programmed talkgroup, it moves on to another site again dwelling for 1-2 seconds and so on until all sites are monitored. Then the process repeats.

Thus to cycle through one system with 5 sites, you are looking at 5-10 seconds. So if you break this up into three systems each having its own system quick key, you are extending the total scan cycle by an additional 10-20 seconds (that 5-10 seconds times the two additional systems). That's probably enough to cause missed traffic.

Using group key quick keys is your best option to reduce the opportunities for missed traffic. This might be one of those things where the more you do something, the less complicated it becomes.

(Hopefully I've explained this so you can make heads and tails out of it).
 

Voyager

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+1 on the Group Quick Keys for the reasons mentioned - you would cut your scan speed on 1/3rd if you separated them into 3 Systems.
 

Voyager

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Not true. The order of TGs have no impact on scan speed. In fact, if there isn't a channel grant, the scanner doesn't even look at the list.

You may be thinking of sorting conventional frequencies which in theory could increase scan speed.
 

XTS3000

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You can set the dwell time (Hold Time) to 0. I do this and scan 4 TRS towers. If there is no activity on all 4 towers, it only takes 1.5 seconds to scan all 4 towers.
 

ofd8001

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If you sort the talkgroups in numerical order it will save time too.

I agree with Voyager.

I believe the only functional value of sorting talkgroups in numerical order is to help find them (either for editing or to confirm their existence).
 
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