It does seem a very temperamental frequency to generate for some weird reason i have never had these problems with any other frequency i have tried different online calculators and brought more accurate components (with expense of long delivery times) i think however i may have found a circuit which seems to fit the criteria perfectly its a modified 555 circuit for 50% duty cycle.

i tested with the transistor to make sure it worked then removed as i will replace that part of the circuit with a constant current driver, i modified the values using the formula given on the website...

"Theoretical frequency can be calculated by:

f=1/(1.4 RC)

where f is frequency in kilohertz, R is resistance in kilohms, and C is capacitance in microfarads.

38 kilohertz = 1/(1.4 * 18.7969 kilohms * 0.001 microfarads)"

so 56.24 kilohertz = 1/(1.4 * 12.7 kilohms * 0.001microfarads) i used a 8.2 kilohm resistor with a 5k pot and once again i could tune it to 55.56 and it then jumps to 57.14 completly skipping 56 i tried adding a 1k pot in and using that to further tune it and it still functioned the same, i added a 500pf capacitor nope still missing then tried dozens of combinations, am i not using this formula correctly?

I do realise the bandwidth on a infrared receiver is 1khz so it can be off by that amount however 55.56 could drift down below the 1khz threshold through thermal drift and other factors so i would like to get it atleast 55.90 or 56.50 that way i dont have to worry about this.

the website with this information is:

Infrared555