[time-nuts] 5V GPS antenna on 3.3V device?

[jmfranke]

Bias T yes, but also a light load on the receiver antenna jack to let the 
receiver know there is an external antenna and thus switch from the internal 
patch antenna to the external antenna jack. I determined the required load 
resistance by using a resistance box coupled to the antenna and starting at 
50K, lowering the resistance until the receiver switched - at which time all 
of the signals disappeared. DO NOT GO BELOW ABOUT 200 OHMS.

John  WA4WDL
--------------------------------------------------
From: "David McGaw" <n1hac at Alum.Dartmouth.ORG>
Sent: Tuesday, April 10, 2012 12:29 AM
To: "Discussion of precise time and frequency measurement" 
<time-nuts at febo.com>
Subject: Re: [time-nuts] 5V GPS antenna on 3.3V device?

> Yes, a bias T is needed.  The same is true for some hand-helds like the 
> Garmin GPS-60CSx which also only put out 3V.  5V antennas like the Synergy 
> VIC-100 have very low gain at 3V.
>
> 73,
>
> David N1HAC
>
> On 4/9/12 11:29 PM, lstoskopf at cox.net wrote:
>> How's the best way to run an older 5V antenna with the new 3.3V GPS 
>> engines?  Bias T?
>>
>> N0UU
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at 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 at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>