[time-nuts] Z3815A Antenna Pad Query
Hello, I am new to the group. Recently got a Z3815A (module type) and was looking at ZL1BPU's User Guide. Don't ask me why but before I soldered a BNC coax to the bottom antenna pads I checked them with an ohmmeter and found 2.5K across the signal pad and ground. I was surprised since there will be a 5VDC across them when powered. I don't have a schematic . is this correct? Perhaps someone with a ZA3815A can put an ohmmeter across their antenna connector and confirm if normal finding? I am reluctant to power it up if a potential problem exists that I could make worse. Much appreciated TIA Jerry K1JOS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Z3815A Antenna Pad Query
Which type of ohmmeter have you used? What voltage does it use to make the measure? What polarity? If the voltage is greater than 700mV and the positive was put on ground maybe some diode has turned on... anyway 2.5K on 5V is 2mA. I have never made such a test on a GPS receiver. I can try on a TBolt since it is off now. On Mon, Aug 13, 2012 at 11:40 PM, Jerry jster...@att.net wrote: Hello, I am new to the group. Recently got a Z3815A (module type) and was looking at ZL1BPU's User Guide. Don't ask me why but before I soldered a BNC coax to the bottom antenna pads I checked them with an ohmmeter and found 2.5K across the signal pad and ground. I was surprised since there will be a 5VDC across them when powered. I don't have a schematic . is this correct? Perhaps someone with a ZA3815A can put an ohmmeter across their antenna connector and confirm if normal finding? I am reluctant to power it up if a potential problem exists that I could make worse. Much appreciated TIA Jerry K1JOS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Z3815A Antenna Pad Query
Well, the TBolt measures 1086OHM on the antenna connector with a test voltage of 3V (2K range on the multimeter) and open circuit when switching to 20K range with 800mV test voltage, positive on antenna and negative on GND. The Motorola M12 has 1940OHM (2K) and open on 20K. The uBlox LEA-5T is open (2K and 20K) and the Navsync CW12 is the same. On Tue, Aug 14, 2012 at 12:17 AM, Azelio Boriani azelio.bori...@screen.itwrote: Which type of ohmmeter have you used? What voltage does it use to make the measure? What polarity? If the voltage is greater than 700mV and the positive was put on ground maybe some diode has turned on... anyway 2.5K on 5V is 2mA. I have never made such a test on a GPS receiver. I can try on a TBolt since it is off now. On Mon, Aug 13, 2012 at 11:40 PM, Jerry jster...@att.net wrote: Hello, I am new to the group. Recently got a Z3815A (module type) and was looking at ZL1BPU's User Guide. Don't ask me why but before I soldered a BNC coax to the bottom antenna pads I checked them with an ohmmeter and found 2.5K across the signal pad and ground. I was surprised since there will be a 5VDC across them when powered. I don't have a schematic . is this correct? Perhaps someone with a ZA3815A can put an ohmmeter across their antenna connector and confirm if normal finding? I am reluctant to power it up if a potential problem exists that I could make worse. Much appreciated TIA Jerry K1JOS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
