Help with a Variable frequency oscillator design

[Ow@i$]

Need to generate 9.545MHz stable sine wave.... i had gone for crystal oscillator but couldn't find 9.545Mhz crystal...
can u suggest something possibly a stable VFO or DDS chip, preferably not programmable controlled rather voltage controlled ( i don't need to interface uc on for this purpose)

 

[barry]

There are a lot of solutions; how much money do you have? How accurate/stable do you need to be? How pure does your sinewave have to be? If you don't want it to be programmable, that eliminates a number of solutions. A DDS would be a good solution, but they generally need to be programmed. You could build your own fixed-frequency DDS with an FPGA and DAC,

 

[Tunelabguy]

If the only thing preventing you from using a crystal oscillator was the fact that you could not find a standard crystal of this frequency, then just have one made custom. There are many companies that will make custom crystals at whatever frequency you need. Sure, they cost more than a standard frequency, but not so much more that you would be forced into a DDS design. Three that I found on-line are:

https://www.foxonline.com
https://www.icmfg.com/crystals.html
https://www.frequencymanagement.com/html/crystals.html

There are many others. Just Google quartz crystals custom frequency

 

[E-design]

I suppose it depends where you are but in the US, it is easy obtainable.

**broken link removed**
https://www.mouser.com/ProductDetail/ECS/ECS-95-S-4X/?qs=CNVyLAqdhH2fsf4dgCcjDw==
https://www.digikey.com/product-detail/en/ECS-95.4-S-4/X420-ND/79307

 

[goldsmith]

Need to generate 9.545MHz stable sine wave.... i had gone for crystal oscillator but couldn't find 9.545Mhz crystal...
can u suggest something possibly a stable VFO or DDS chip, preferably not programmable controlled rather voltage controlled ( i don't need to interface uc on for this purpose)

Hi Ow@i$

it is easy to obtain !
There are too many ways for this aim . all depends on you and your place and your required specifications .
For example an LF oscillator with pretty pure and stable shape ( like bubba or wien bridge oscillator perhaps ) and then a frequency multiplier ( like something based on gilbert cell ) !
designing a pretty stable square wave and then take it's fundamental harmonic . or .... etc

Best Wishes
Goldsmith

 

[elecbaba]

I can guess from the numbers, you are making a 10 MHz reciever. 9.545 + 0.455 = 10.00. If this is the case, a 10.7 MHz crystal which is very common and is used in FM radio receievers can work after changing intermediate frequeny TO 0.7 MHz.

 

[Ow@i$]

thank you all for your suggestions..!!
not so expensive... yeah pretty stable.... and FPGA and DAC surely is out of approach.... regarding that available on digikey... they are specified with load capacitance as series... not 8pf or etc.... can a series load capacitance crystal be used in cohn crystal oscillator or else where we are suppose to use parallel load capacitance???
moreover i was looking for a tested stable circuit that you guys might have tried and i can than customize it for 9.545Mhz...
@ elecbaba
it can be done but the filter for IF 455Khz is narrow i didn't find 0.7Mhz narrow filter