[time-nuts] Frequency Comparator Ideas needed

[Chris Albertson]

 Seems to me like an HP 5335A is well suited to this task.  It measures
frequency in the required range and has adjustable gate times so you can get
updates at the rate you need.   These sell on eBay for as low as $200 and
from other placed for $600.  They have signal conditioning, and a computer
interface all in one rack mount box.  Accuracy is better then you say you
need.

On Thu, Aug 11, 2011 at 1:10 PM, Dan Kemppainen <dan at irtelemetrics.com>wrote:

> Hi All,
>
> I could clairify things a little. My event of interest is basically a fast
> frequency shift of a signal that drifts between 1800 and 2600Mhz. There is
> slow drift of this signal of many hundreds of Mhz, with fast frequency
> shifts of approximatley +/- 150Khz. I believe that the 150Khz shifts are
> nearly instantaneous, but currently have no way to measure exactly how fast
> they occur. Slow drifts are corrected for by a loop in the down converter.
>
> Currently there is a first down conversion stage to ~900Mhz. This is then
> down converted again to an arbitrary frequency band (50Mhz in this example,
> but this could be moved from ~10Mhz  to 200Mhz or greater).
>
> Obviously it would be advantageous to keep the low frequency band as high
> as possible, at least when trying to determine when the frequency shifts
> occur with any digital detectors. Probably for any analog detectors also.
>
>
>
Chris Albertson
Redondo Beach, California