Thanks for the feedback on the Si5351 as a replacement for crystals.
It would appear that a low cost micro-controller has to be put alongside the Si5351 synthesiser. I wonder if anyone has a complete solution designed and tested. Also, what about programming?
It would seem that there is a real need for a simple KISS way to replace crystals, so I'd be surprised if someone has not already done this. According to Peter Marks the controller should only be a few dollars. This feedback (that you have to tell the Si5351 the frequency every time) is also what Jay told me.
It looks like a total solution that also replaces the oscillator should be possible for under $10.
Please let me know of any links.
The qrplabs progroc is worth looking at -
ReplyDeletehttps://www.qrp-labs.com/progrock.html
"It would seem that there is a real need for a simple KISS way to replace crystals..."
ReplyDeleteA 3D PRINTER!
Thanks for bringng my attention to the QRp-Labs Progrock. Fine, but I would need a solution at half this price!
ReplyDeleteA 3D printer? It might look like a crystal, but that's all!!
Hi Roger,
ReplyDeleteI had a bit to do with the qrpLABS Prog Rock ( programmable xtal) I don't know how you think £13 is a lot for eight programmable banks of three independent frequencies, one or two cut to order crystals cost more and you can't change the frequencies either!
The synth chip is driven with an internal 27MHz xtal. There are three squarewave outputs that are independent . An external switch input then allows which of eight banks are selected, the frequencies are non volatile stored in an AVR processor in the module. You get a >3V output from 3.5KHz to well over 300MHz typically.
If you have a GPS RX module with a 1PPS output you can lock the module to GPS but that does cost one output so two independent outputs.
The set frequencies are set by using a BCD coded DIP switch to input each wanted frequency- no additional gear needed.
I have had a few modules for a few years, they are extremly useful in any Lab. One of the original applications was for PMR conversions, you can even rip out multiplier strips if you want. I would advise that you think again Roger, you don't have to fiddle around for crystals, you just program what you need whilst being quickly able to alter the Fx when you want.
73, Alan G8LCO
Thanks Alan. I am sure the Progrock is good, but at $0.35 for the crystal and 3p for the 2N3904 takes some beating. For obscure frequencies the Progrock is a good solution.
ReplyDelete