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Quantar Astro/Analog Smartzone Omnilink Downtime???

Posted: Tue Jul 25, 2006 10:31 pm
by DES-AJ
Ok this is an Australian Government Radio Network question but it would be the same with any Quantar SZ Omni system including those in the US.

My question is regarding downtime on the system - is it possable for a SZ Omnilink system such as the NSW GRN to re route the base control channel data on a smartzone system between multiple Quantars to share the stress of 50W 24/7 365 days?

I'm aware that theirs several Control Channels for each site (Alternative/Backup CC's) But the main one for this site is used 99% of the time.

I'm quoting my friend Mike who discribed the paticular site to me and how sometime he gets better signal than other times...
I've heard that the antenna on this paticular site is made up of 4 or 5 dipole arrays with 5 channels feeding into each array. When the CC gets switched to a different base, and therefore a different antenna array, the signal path changes and that's why I get the change in reception.
So anyone in the know here that could tell me if they do reroute and a few quantars share the load of 24/7 Control Channel data TX?

Also anyone know how much downtime is supposed to be provided to a Quantar running 50watts?

Thanks all :wink:

AJ

Posted: Tue Jul 25, 2006 11:11 pm
by mr.syntrx
Yep, the system most certainly can do that.

Posted: Wed Jul 26, 2006 3:01 am
by RocketNJ
In SmartZone operation the prime site controller codeplugs are set to not do a midnight rollover of control channels. Channel 1 is usually set as first priority, channel 2 as second, and so forth.

The system manager can elect to have another control channel set as first priority if they desire.

Posted: Wed Jul 26, 2006 3:33 am
by Bruce1807
The base stations are made for this type of abuse, I'v not had a PA failure for over 2 years on a control channel and mine are all running 100W or 150W. (Quantar/Quantro) but then thats why your sitelink is connected to channel 2 in case channel 1 fails.
I think NSW has a SZ 4.1 system and RocketNJ is correct in stating that rollover is no longer used.

I don't know if there is simulcast sites in that system but that could help explain the reception Mike has.
It may also be as simple as garbage in --> garbage out.
Is he outback where he would only pick up one site?

I know a system I used to look after in London, we had the channels 1&3 on one antenna and 2&4 on another. But that was a Smartnet.

Posted: Wed Jul 26, 2006 7:09 am
by RFguy
but then thats why your sitelink is connected to channel 2 in case channel 1 fails
This is not correct. The site link is not effected if the PA in the channel that has the site link fails. The only time that the site link is effected is if the station is turned off, reset or if the station control module fails.

Posted: Wed Jul 26, 2006 11:36 am
by Bruce1807
I guess I should have clarified.
A PA can take down the complete station (I have seen one blow the fuses)
The sitelink is in channel 2 in case of catasrophic failure of channel 1

Posted: Fri Jul 28, 2006 9:05 pm
by SZ$DEF
Quantars are designed for 100% duty cycle, so operating the CC on the same Quantar should not increase the failure rate of the box above any other. You also must take into account the CC list in the portable and mobile radios. If they do not all have the primary CC AND alternate CCs programmed into their trunking CC lists, they may be slower at finding CCs that are not in the list and may cause some perceived problems by the users if the unit has to go to the full spectrum CC scan to find the site.