Quantar Question as backup

[FMROB]

Hello all,

Here is what I am thinking, and have some questions.

Two quantars with sam boards and enhanced wildcards. One is a primary location, the other is back-up location. Both go through microwave to a dispatch point and is hooked to a sepctra tac voter and then to a console.

Both obviously get set as base stations, as thy need to act as voting rx'rs. I would like the dispatcher to be able to switch between the two stations for TX in case of failure. I would also like the back-up location to automatically switch to repeater upon loss of guard tone to that unit, hence if the voter or link goes down the backup sight would work as a repeater, and the main site would shut down completely. The main sight is more susceptible to damage due to weather, so this is my concern.

Any thoughts, comments, questions. I am really looking for someone to give me detailed programming instructions. If you think that you would be able to help, you could certainly post here and you have my great thanks. If you feel that it will be very detailed please PM so we can work something out, I will gladly compensate you for your time. I just need to get this done quickly. Thanks, Rob

[d119]

The way to set this up is to obviously configure everything as 4-wire operation and link to your voter on the receive side.

You didn't mention what type of dispatch console you're using. I'll assume it's some flavor of Centracom.

Using an Aux IO, you will want to switch the TX side of the wireline between the two sites. Default = main site, switched = backup site.

Using fallback in-cabinet repeat, you could accomplish what you want as far as a "failsafe" is concerned, but the issue arises when the wireline to the main site goes away and the dispatcher switches to the backup site, the main site goes into fallback repeat, and the units cannot hear each other as there will be two transmitters up at one time (main in fallback, backup in voted repeat, single-site).

[FMROB]

Thank you for the reply. We are using an orbacom console system.

You have hit the nail on the head. How do I accomplish a stand alone back up repeater system with two sites. I guess that I could only set one site for in cabinet fall back repeat. Any other thoughts, I do have SAM modules in both boxes.

Many on here know that the SAM is my arch enemy. I still can't figure out how to program the stupid thing, even following the manuals to the tee.

Any other toughts or ideas are appreciated. Thanks, Rob

[Q2222A]

The SAM board will only turn on/off "repeat" when the Quantar is programmed as a Repeater. It will not work if programmed as a BASE. You can however, install an external DTMF decoder or use some other method to get a closure on the 50 pin connector between pins 7 (Ground) & 16 (In-Cabinet Repeat). This only works when the Wildcard function is disabled.

Dennis

[Jim202]

Have you thought about using a different PL tone on the input with a common tone on the output
for both radios. This way you wouldn't have to worry about any auto system. Just let the users
do the selecting. You could have both radios set up for repeat and not have to do anything.

Jim

[FMROB]

The two PL will not work as there are tomany surrounding departments that will not be very happy on mutual aid calls.

Quick question, When the Quantar is programmed as a base, the RX section can be set to send out the 2175 tone on the wireline and independantly TX at the same time?

Thanks, Rob

[d119]

Program the quantars like this. Lets assume your RX frequency is 160.0 and your TX frequency is 150.0

MAIN QUANTAR:

F1: TX 150.000 RX 160.000
F2: TX 000.000 RX 160.000

BACKUP QUANTAR:

F1: TX 000.000 RX 160.000
F2: TX 150.000 RX 160.000

Set your Orbacom up for multifreq operation.

When the console keys up on F1, main comes up.
When the console keys up on F2, backup comes up.

You can still vote using the comparator, since receive is always active. The only issue would be that undoubtedly the comparator keys the stations for repeat operation, so you'd have to figure out a way to bypass the comparator in the event of a failure so your F2 function tones could make it to the repeater. Perhaps a separate wireline?

I know this works very well with AstroTAC comparators and DIU's since the ATAC passes the frequency data along to the station... Here ya go folks, main/standby ASTRO voting!

[RKG]

You cannot use the Quantar FBICR feature in a voted system. The standby machine does not normally see a key-up command, and so it would immediately default into FBICR mode, which you don't want. Likewise the main, if you switched the Tx line from main to standby.

What some folks do is this:

Program both machines as repeaters (even though wired as voted transmitters).

Program the SAMS for a DTMF sequence to put both into Repeater Disable mode.

Now, when the comparator goes down, someone takes a portable radio and sends the DTMF sequence for one or the other Quantar to put it in Repeater Enable mode.

Note that you'll also need a Wildcard table to put the machines into Repeater Disable mode on Cold start or Warm start.

And, of course, when the rare event happens, you'll need an operator who remembers that the feature is available and what the damn DTMF code is.

[FMROB]

RKG,

So if I have a voting system and only one quantar programmed as a base with ICFBR it will work properly? Mybe I am missing what ICFBR is really used for. I have not played with the feature much.

[RKG]

Yes, if you have only one full Quantar.

No, if you have two Quantars (one Main and one Standby).

What FBICR does is as follows:

If local receiver becomes "qualified," and

If local transmitter does not receive external key signal over the wireline within X ms, then

Local transmitter keys and repeats audio received over local receiver.

It was designed for SpectraTac voted systems with a single transmitter.

It doesn't work with a two (or more) transmitter voted system, because by definition one (or more) of the stations will be have its (or their) receivers become qualified without its (or their) transmitter receiving a key signal over the wireline.

[xmo]

Don't worry about FBICR.

A little effort in system configuration and programming up front can result in a very reliable system that's easy for everyone to use with automatic main / standby operation.

Configure the console and voter to send their transmit audio & TRC keying through the microwave to BOTH stations.

At the main station configure a wildcard output contact to close every time the station receives a wireline PTT. At the console/voter site cross-connect the incoming E lead closure from the main site to the M lead going toward the standby site. At the standby site connect the incoming contact closure to a wildcard input. Program the wildcard configuration so that every time a wireline PTT is received the station will wait a few milliseconds, then if the the wildcard input does NOT become active, the station will key.

In this way the standby site transmitter will automatically be activated if the main site is lost, if the main quantar fails, if power is off, or if the microwave to the main site is disrupted. The standby activation decision is made on every transmission. If the failure [e.g. power outage] self-corrects, the system will automatically revert to normal use of the main site.

It's also safe in that, if connectivity is lost to the backup site, it sits idle and does not interfere with the main site.

If connectivity is lost to BOTH sites - or if the console / voter is lost - that is where the SAM option comes in.

Provide dispatch with a backup radio - a control station, a console mounted mobile, or even a portable - so long as it can talk to both the main and standby sites. This radio would only be used in the event of one of those serious outages where the system can't repeat.

Put two modes into that radio - one for main and one for standby. Create two MDC RAC codes. The radio mode named "MAIN REPEAT" will send RAC code one on every PTT. The radio mode named "STANDBY REPEAT" will send RAC code two.

Program each Quantar's SAM with a decoder target for each of the two RAC codes. The main Quantar will enable repeat on receipt of code one and disable repeat on receipt of code two. The standby Quantar will do the reverse.

You should also implement some alarms so the dispatcher can notify a support person when something is not right.

Set up alarms from the voter 'line fail' outputs, from the microwave, and in addition, you could program the backup Quantar to generate a wildcard output any time it keys up from wireline because it didn't see that the main was active. Bring that back to the dispatch center with the other half of the E&M.

If you don't have E&M on the microwave path, then implement the automatic site selection by installing a receiver at the standby site. Configure that receiver to watch the main site repeater output and connect its 'COR' to the Quantar wildcard input.

[WB5ITT]

FBICR is what I am planning to use on one ham rptr setup...I have a repeater on one tower 10 miles from the controller (RLC-DSP404) which sits at a "hub" site with remote bases, other links and repeaters (a 220 rptr is on the RLC site; the UHF rptr is on a 600ft tower and we havent been able to get the 220 antenna up there...and this is a building top with NO feedline loss for the links!!!..., VoIP connection (OC48 Fiber), etc. The system is linked to the RLC using full duplex 430MHz links....IF the RLC fails or the link fails, the FBICR takes over and connnects the local rcvr to the local xmtr with its own local controller...and it is on the air! Of course this means no P25 unless the FBICR is active...eehh Im the only one with P25 anyway!