Page 1 of 1

XPR4550 / XPR5550 - Analog Mode Squelch Adjustment?

Posted: Tue Aug 05, 2014 3:51 am
by g8tzl2004
How do you adjust the analog squelch level in an XPR4550 or XPR5550?

The user can toggle between Normal and Tight SQ levels but I can find no SQ softpot adjustment in the Tuner software.

Hopefully its not a fixed factory "Normal" level which will probably be set too high for weak signal working?

On my MCS and CDM radios you can adjust the SQ softpots in the tuner software so that the SQ opens on a really weak signal. On XTL radios, there is a User Adjustable 0 - 15 SQ setting and level 1 is set just right to RX more or less unreadable signals...so you really need to set the XTL SQ level at say 2 or 3 but at least you have the option to set the SQ at the absolute noise threshold!!

There is an RSSI dBm adjustment with the XPR radios but I'm thinking that is only used to restrict TX based on the strength of the RX signal??

Hope someone can help.

Re: XPR4550 / XPR5550 - Analog Mode Squelch Adjustment?

Posted: Sun Aug 10, 2014 12:39 pm
by g8tzl2004
Any ideas?

Re: XPR4550 / XPR5550 - Analog Mode Squelch Adjustment?

Posted: Thu Aug 21, 2014 12:11 pm
by g8tzl2004
Any thoughts?

Re: XPR4550 / XPR5550 - Analog Mode Squelch Adjustment?

Posted: Wed Jan 07, 2015 11:28 pm
by com501
There is no squelch pot adjustment. The DSP sets the squelch level according to the algorithm flashed into the firmware, either normal or tight. Mine opens on carrier squelch on UHF at around -123dbm. VHF both of my mobiles open around -124to -125dbm. I optimized my radios using autotune on the Aeroflex, but I could not tell any appreciable difference.

Re: XPR4550 / XPR5550 - Analog Mode Squelch Adjustment?

Posted: Fri Jan 16, 2015 9:10 am
by g8tzl2004
Thanks com501.

I wonder if you have checked how RX sensitivity compares for 12dB SINAD between the XPR4550 and XPR5550 for both UHF and VHF?

Is an XPR5550 more sensitive than a XPR4550? The portable XPR7550 is regarded as being significantly more sensitive than the earlier XPR6550...and official specs, as usual, are not a true guide to actual sensitivity..only a worst case scenario.