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As mentioned in one of the earlier post the SI4432 RX module has only limited mirror suppression. The purpose of the 434MHz IF filter is to remove this unwanted mirror. But how do you know if removing

The architecture of that part looks an awful lot like an Si5351. A reference clock into a PLL with VCO, the VCO drives three output dividers, just like the Si5351 The article you pointed to states: "

Very interesting read indeed, when the parts arrive I will check his post about phase noise measurements to see if he updated the tests with out of spec clock. Here's my source, Hans of QRP-Labs:

Stability.

What about the use of a “jitter cleaner” chip whos output clock is equal to the imput cluck but uses a pll to reduce jitter. Then perhaps the Neo-7M could drive the jitter cleraner whose output,

I agree, I'm planning to try a tinySA with a stock Si4432 module once I get the parts in. But it's been a fun discussion, I learned a bunch. And accurate frequency standards do have their uses. Jerry,

As the minimum frequency step for the SI4432 is above 100Hz why would you care anyway? Calibrate from time to time against a known frequency using a calculated compensation and forget about it. But

The NEO-7M output is not great, but PLL's can be surprisingly forgiving. Due to the divide ratio in the PLL, the phase detector is not getting updated very often. And the low pass filter between the

Eric, Excellent! Thanks for looking into this. Some of the other GPS receivers do give a clean reference clock of perhaps 10mhz.? But not the NEO-7M. Getting back to the Si4432, it seems the best way

Some further analysis on high frequency the output of the NEO-7M The NEO-7M creates its high frequency output by setting the count of the high and the low output in 48MHz ticks. The first divider can

To be fair, while Hans did say the 9mhz reference into an Si5351A "did indeed degrade various aspects, including phase noise and spectral purity" he also said that was at VHF.? ? And that at very

Dragan, Yes, the Si5351A sort of works outside the spec'd 25 or 27 mhz, as per post 704 Your reference is mostly pushing the reference frequency around until the Si5351 loses lock. He doesn't quantify

Si5351 can work with clocks far away from the 25-27Mhz range so lower clocks like 12MHz should not be an issue:

Does the NEO-7M work at all when dividing 48mhz by two, giving a clean 24mhz? Even if at a moderately low level? If so, the NEO-7M could drive a 24mhz reference into a cheap SI5351A directly, since

There's a video here which shows the jitter clearly. Also, the way to program the output.

The NEO-7M has a dual modulus divider to deal with the non-integer ratio of 48/10. It sometimes divides by one number, sometimes divides by a value one less than that number. This will almost

There is some talk around other forums and with other experimenters that what you are saying is the case about jitter on the output. Staying with even divisor ratio's gives the cleanest output, but I

The NEO-7M calims to be able to output GPS locked frequencies till 10MHz. But is this usable??? As measured using an external 30dB attenuator. Here is the 10MHz output 10MHz is there but 2,6 and 18MHz

Wow, a dirty divide like that to get a 10mhz reference is really nasty! I had come to expect 10mhz as pretty much standard, and expected it to be clean. It's possible everything would just work with a

It's funny that the topic is going to GPS..?? I haven't gotten to my tinySA yet because I have been finishing up my last project. I built a GPS corrected VFO basically from a QEX article. I am using