While they kind of worked with a hockey-puck antenna, they are

If the antenna is open or shorted you will get an alarm. Manual is on line.

IIRC, using the down-converter option for long feedlines was

Dick, I have had a couple of the XL-AK receivers here for several years. They both do not have the down converter option and do put out 5 volts to the antenna jack. It is simple to measure with a volt meter into the antenna jack. While they kind of worked with a hockey-puck antenna, they are much happier with a bullet type of amplified antenna. They would loose satellite lock from time to time with the hockey-puck but are rock steady with the bullet. If the antenna is open or shorted you will get an alarm. Manual is on line. IIRC, using the down-converter option for long feedlines was paired with an up- converter in the receiver. If you have the up-converter in your receiver you may be able to just bypass it. Al > Hi > > The older GPS units had a downconverter in the antenna and passed an IF > frequency > back to the receiver. There also was an era when the standard antenna was > fed 12V > (rather than 5V) and had 50 db of gain (rather than 20 to 30 db). Most > modern hockey > pucks will be unhappy with 12V. > > Bob > >> On Aug 25, 2017, at 6:13 PM, Richard Solomon <w1ksz@outlook.com> wrote: >> >> I was given two of these about 20 some years ago. At that time they both >> worked >> >> fine, except the "keep-alive" batteries were quite low. But they did lock >> up to the >> >> GPS Satellites. >> >> >> I pulled one out today to try out (slow day !!) but I had this nagging >> feeling that >> >> they required a different antenna than the run of the mill GPSDO. I have >> one of >> >> the e-Bay "hockey puck" antennas hooked up to it and the status window >> says >> >> ..."looking for satellites"... . >> >> >> Do the TrueTimes require something special in an antenna ? >> >> >> Thanks, Dick, W1KSZ