PowerFlarm and Mode C

Wondering if someone here might be able to answer this question.

Does PowerFlarm need to have a good GPS fix before it will respond to a Mode C alert?

I have been flying with a Zaon MRX PCAS for years now. Many of those years I used the ZAON in parallel with PowerFlarm. My experience has been that the Zaon completely out performs the PowerFlarm in picking up Mode C signals.

This past weekend, with the glider in the hanger, the Zaon alerted to every single towplane departure. PowerFlarm scored a zero. Nothing.

So, while I know the ADSB antenna on the PowerFlarm does receive (ADSB targets and other Mode C targets) it should have had no trouble receiving the towplane signals with respect to signal strength as the towplane was only 300' away laterally.

As a result, I'm wondering if the PowerFlarm simply ignores all Mode C info if it has not been able to lock on to satelites OR if this has to do with the towplane being at the same altitude as my glider in the hanger. Is it the issue of "same altitude" that's been mentioned many times before where the PowerFlarm may ignore same altitude alerts.

This is the relevant portion of my config file...

$PFLAC,S,ADSBRANGE,65535
$PFLAC,S,ADSBVRANGE,1500
$PFLAC,S,PCASRANGE,7000
$PFLAC,S,PCASVRANGE,600
$PFLAC,S,MODEC,1
$PFLAC,S,OWNMODEC,1
$PFLAC,S,PCASCALIBRATION,30
$PFLAC,S,XPDR,2
$PFLAC,S,MODESALT,0

Either way, I will not be giving up my Zaon any time soon and I even went on ebay and picked up a backup since they are no longer in production. Fantastic little units.

Mark