Astro Spectra keeps changing sites: Smartzone

[motorolaaustralia]

Hi all,
I am working on a W4 Astro Spectra. For some reason it keeps trying to affiliate for longer than normal.

It's like it is going through every possible channel to find the best signal or something. I have copied every parameter from another working radio and it's still doing the same thing.

I have tried base antennas and mobile antennas. Radio specs are fine.

When it eventually affiliates, TX and RX are fine. After a few minutes it will start searching again.

Any ideas what else I may have to configure?

Regards
Dom.

[mr.syntrx]

Check the RSSI thresholds under SmartZone Environment, under Trunking Wide Options. (In RSS at least. I don't know where this information lives under CPS, but I expect it has a similar name.)

It sounds like the radio is unhappy with the CCs it's detecting, and continuing to vote because it believes the RSSI is below its minimum acceptable level.

[bellersley]

It's like it is going through every possible channel to find the best signal or something.

What's wrong with that? That's exactly what it's supposed to do.

Assuming it has "last site" information, it will look at the last used control channel then check it's RSSI with the sites in the neighbour list. If it finds a neighbour that's got a better RSSI, it will affiliate over to that neighbour, then begin searching it's neighbour list. If it can't find a control channel on the last used site, or if the last site information isn't present it will begin at the first control channel and go through them all until it finds the control channel with the best RSSI and go through the above neighbour list procedure.

You can set the RSSI threshold in the RSS/CPS so the radio will either begin searching sooner or hang on to a particular tower until it's pretty well not there.

In the city over from me, Toronto is on a 4 site SmartZone system. Their RSSI values have been messed with slightly to make the radios bounce around trying to find a better site more often than the defaults. This results in clearer communications as the 4 sites have a LOT of overlap (so much so that you can almost always get at least 2 sites without an antenna anywhere in the city).

Edit:

I forgot to answer your question all together! I'd go with what Mr. Syntrx is suggesting. Check to make sure your radio's RSSI levels aren't set too high as it would result in your radio trying to seek out new life and new civilizations, aka a better site (it's been a long night). I had a radio whos RSSI values were all peaked at maximum, the radio would take forever to be happy with a site but it would always miss comms as it tried to find a new best friend. Setting the values to the exact same as another radio that is known to be working fine SHOULD remedy that problem so I'm not too sure what is up. It could be possible that something in your radio isn't happy and it's giving a false RSSI reading.

[tvsjr]

It should look for better sites, but his hysteresis to too low. If the radio votes up a -70dBm site, it shouldn't abandon it for a -68dBm site. If it finds a -50dBm site, then, potentially yes.

Like Syntrx said, check the SmartZone Environment settings.

[motorolaaustralia]

I'll try playing with the RSSI settings.

There is 32 sites and I really don't want it searching all of them for each talkgroup I change to.

I'm going to check the VCO. I reckon I saw Fail 001 flash up on the screen. I'll put some test conventional channels in.

Thanks all!

Dom

[Bruce1807]

leave it powered on for 20 minutes. If you have full spectrum scan for the control channels enabled (which I believe you do) it needs to learn the system.
This is common with a new radio added to the system as well as a reflashed radio.

after 20 or so minutes(depends how many sites it can see) switch it off and back on .
It should go straight into action.

[RKG]

I'd also check the sensitivity of the receiver.

[wavetar]

What is the serial number of the unit? If it falls between xxxxDCxxxx (FEB 2003) and xxxxEVxxxx (Oct 2004), then it requires a firmware patch for it to "see" the RSSI levels properly. That's nearly 2 years worth of Astro Spectras out there which have this issue.

For the above issue, if you compare it to another unit of a different serial range, you'll see it measures the signal as approx 20 units lower when the RSSI button is pressed.

This was covered on a Service Bulletin, although I'd have to dig around a bit to tell you which one. Motorola made a small program available called "FIX_RSSI.exe" which repaired the problem. It's sort of like a mini Flashport upgrade. You require a SmartRIB for it, but it only takes a few seconds to do.

Todd

[Pj]

SRN - 1477A
APC - 412, 494, 526
December 2004 (Up Issued Apr 2005)

Distribution: MOL / Resources / Service / Two-Way Mobiles Informational Only

From: ASTRO Spectra, ASTRO Spectra Plus Product Group

Subject: ASTRO Spectra and ASTRO Spectra Plus stays in poor audio quality while in range of better site(s).

Symptoms:
ASTRO Spectra and ASTRO Spectra Plus mobile radio stays on a site receiving poor audio quality while in range of better site(s). The mobile radio transmissions have poor audio quality even when the system is providing acceptable inbound coverage from one or more sites in the transmit location.

This problem is present in the radio in SmartZone and OmniLink trunking systems in the 800, UHF and VHF bands.

Potential Problem Radios:
ASTRO Spectra and ASTRO Spectra Plus radios manufactured between February 2003 and October 2004, denoted by serial numbers xxxxDCxxxx through xxxxEVxxxx.

Cause: Hardware change not coordinated with appropriate codeplug value change.

Corrective Action:
Run CPFix FIX_RSSI.exe to correct RSSI DSP offset on potential ASTRO Spectra problem radios or run CPFix 05003 to correct RSSI DSP offset on potential ASTRO Spectra Plus problem radios See below for a description of CPFixes.

FIX_RSSI.exe and CPFix 05003 enable the user to program a new value (146) to the RSSI DSP Offset field. Recovery.exe and CPFix 05005 enable the user to recover the original value (168) of the RSSI DSP Offset field.
Important Information – When to Use the CPfix If unsure – TEST
FIX_RSSI.exe CPFix or CPFix 05003 are only needed for radios with serial numbers between xxxxDCxxxx (Feb 2003) and xxxxEVxxxx (Oct 2004).
If the serial number of the radio is between xxxxDCxxxx (Feb 2003) xxxxDHxxxx (April 2003), close to xxxxDCxxxx (Feb 2003) or xxxxEVxxxx (Oct 2004), or if the radio in question has a repair history that makes it unclear whether the change is needed, then and only then use “TEST” method to verify.

For example, the radio's original VOCON board has been replaced with a new VOCON board, which might be built between Feb 2003 and Oct 2004 time period.

Test methods to verify the need to change the RSSI Offset value:
1. Compare RSSI readings at the same input signal strength between the radio under test and a known good radio; if RSSI reading
is about 20 points lower than the known good radio, the radio needs FIX_RSSI.exe CPfix or CPFix 05003.

a. Both radios will need the Site button programmed via CPS. A short press of the Site button will display the Site ID and
the current RSSI.

b. Both radios must be the same hardware model (excluding control head differences) and have the same hardware
enhancements. e.g. a pre-Amp that is available in VHF and UHF models should not be compared with a non-pre-Amp model.

c. The measurements must be taken in the same good coverage location.

d. The location should not be an area of simulcast overlap coverage because signal from each different site transmitter will
be received at a different RSSI even though the Site ID will be the same.

OR

2. Inject a signal of -100 dBm using a trunking service monitor; if the RSSI reading is below a value of 30 then the radio needs
FIX_RSSI.exe CPfix or CPFix 05003

a. The radio will need the Site button programmed via CPS. A short press of this button will display the Site ID and the
current RSSI.

Note: If a radio has been incorrectly modified using the FIX_RSSI.exe CPFix or CPFix 05003, then use the recovery.exe CPFix
or CPFix 05005 to restore the original RSSI offset (168) value. Refer to CPFix Readme file for execution instructions.

To obtain this RSSI Offset CPfix tool, contact 1-888-567-7347 follow prompts to subscriber support and submit a request.

[bellersley]

The OPP up here in Ontario had all of their radios re-flashed with new firmware a year or so ago to fix an RSSI problem. I assume it is the same issue that PJ posted an SRN for. I hadn't thought of that, but it's probably a good bet that's your problem.