[time-nuts] Active antennas for a Thunderbolt...
Didier Juges
shalimr9 at gmail.com
Tue Jul 31 00:01:12 UTC 2012
The coax is actually 50 feet of good quality 75 ohm cable that I bought for this (rated for satellite TV). I have not measured the loss accurately but I did check it at 2GHz when I bought it and it was good.
Didier
Tom Knox <actast at hotmail.com> wrote:
>
>Hi;
>Is your coax 50 or 75 ohm? Is it microwave rated? and have you tried
>changing coax length? None of these should be a major factor but could
>make a difference.
>Best Wishes;
>Thomas Knox
>
>
>
>> From: shalimr9 at gmail.com
>> Date: Mon, 30 Jul 2012 13:46:40 -0500
>> To: time-nuts at febo.com
>> Subject: Re: [time-nuts] Active antennas for a Thunderbolt...
>>
>> Chuck,
>>
>> I have one of the original red box TB. It came with the Trimble
>Bullet antenna that is specified in the TB datasheet.
>>
>> The antenna works but gives extremely poor results. The TB works
>much better with the Symmetricom antenna that is sometimes available on
>eBay.
>>
>> The Bullet antenna is usable with other GPS receivers, so I know it
>is not bad. Its just a poor match for the TB.
>>
>> Didier KO4BB
>>
>>
>> Chuck Harris <cfharris at erols.com> wrote:
>>
>> >Ok, I'm getting a little puzzled. I have a TB that came from one of
>> >the early groups sold by John Ackermann and TVB as part of the TAPR
>> >buy.
>> >It works nicely, but like all TB's, it is deaf as a post, and needs
>a
>> >high gain antenna.... When I first got the TB, I tried it with a
>> >Motorola
>> >hockey puck antenna, with about 17db gain, and if it is outside in
>the
>> >clear, it works nicely... but LH shows the satellites signals are
>all
>> >down in the mud.
>> >
>> >...So...
>> >
>> >I bought the active antenna that the TB data sheet said belonged
>with
>> >the TB, a 24045-10 bullet antenna, and *NO* satellites are visible..
>> >the antenna is dead.
>> >
>> >I'm no stranger to getting cheated on things I buy, so I chalked it
>up
>> >to bad luck, and put my Motorola hockey puck antenna back on my TB.
>> >
>> >...Then....
>> >
>> >A couple of days ago another active antenna became available, a
>> >Micro Pulse 1934NW/C 50db antenna from a DATUM INC GPSDO. I checked
>> >its data sheet, and it powers off of +5V @ 38ma, so I bought it,
>> >hooked it up to my TB, and again *NO* satellites are visible... the
>> >antenna is dead.
>> >
>> >I put a "T" in the line, and the voltage heading up to the antenna
>is
>> >around +4.5V... The spec sheet says it will work down to +3V.
>> >
>> >Am I doing something wrong here? Or am I just unlucky?
>> >
>> >-Chuck Harris
>> >
>> >_______________________________________________
>> >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.
>>
>> --
>> Sent from my Motorola Droid Razr phone with K-9 Mail. Please excuse
>my brevity.
>> _______________________________________________
>> 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.
--
Sent from my Motorola Droid Razr phone with K-9 Mail. Please excuse my brevity.
More information about the Time-nuts_lists.febo.com
mailing list