[time-nuts] GPS simulator,

J. Forster jfor at quik.com
Thu Nov 25 14:39:21 UTC 2010


Agreed. The trick is to properly partition what is done in hardware ane
what is done in software. This could eliminate a lot of logic hardware.

Clearly, the RF stuff and modulator are hardware.
Ditto PR code generation.
Everything else in SW, I think.

FWIW,

-John

===============


> Hi
>
> One bit serial at 16 MHz isn't all that fancy any more. Sounds like a
> shift register feeding a couple filters.
>
> The money must be in the receive side.
>
> Bob
>
> On Nov 24, 2010, at 5:14 PM, ernieperes at aol.com wrote:
>
>>
>>
>>
>> Hi,
>>
>>   found an interesting unit. I think it is not for the usual pocket
>> money for a time-nuts.
>>   have a look...
>>
>>       http://www.chronos.co.uk/pdfs/rac/labsat.pdf
>>
>> Rgds Ernie.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: John Green <wpxs472 at gmail.com>
>> To: time-nuts at febo.com
>> Sent: Mon, Nov 22, 2010 6:43 pm
>> Subject: [time-nuts] GPS jamming susceptibility
>>
>>
>> Given that this is an extremely sensitive topic and completely illegal
>> lso, let me just state at the outset that I have no interest in
>> amming anyone's GPS. A while back, I was looking at one of those
>> hinese discount electronics websites, I'm sure we all have, and
>> oticed a GPS jammer for sale. I had been wanting to do some jamming
>> usceptibility testing for quite some time but had never got around to
>> uilding a generator to test with. The thing was cheap so I ordered
>> t. After it arrived, I opened it up, first thing, to see how it was
>> ade. It has a dual 555 oscillator, a couple of analog switches, a 1.9
>> Hz VCO, a single amplifier. It doesn't look capable of putting out
>> ore than 50 milliwatts or so into a 2 inch antenna. I was somewhat
>> ubious that it would do anything, so I took it to the bench where the
>> 3801 lives and turned it on. Within 2 seconds, the holdover LED lit.
>> immediately turned it off and within a few more seconds, the
>> oldover LED was back off. The GPS antenna is perhaps 35 feet away
>> ith a cinder block wall, a brick wall, and a metal roof in between. I
>> lso put a 15 Db attenuator between it and the antenna with almost the
>> ame result. I am going to do more testing with it wired into the GPS
>> ownfeed an an adjustable attenuator in line just to see how much
>> ignal it takes. That way, there will be little danger of messing with
>> nyone's reception. It is just a simple sweeper so it must do its job
>> y brute force. I am amazed that it took so little to shut my Z3801
>> own. Has anyone here had any actual experience testing GPS receivers
>> or susceptibility?
>> _______________________________________________
>> ime-nuts mailing list -- time-nuts at febo.com
>> o unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> nd 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.
>
>
> _______________________________________________
> 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.
>
>






More information about the Time-nuts_lists.febo.com mailing list