Frequency divider

[rodnro]

Can any one help.I need to build a simple frequency divider,a square wave input to about half the frequency out,adjustable,say 10% either side.I have tried a couple circuits using a 555 or 4001.They work but the output is not linear to the input as the frequency goes up and down.If adjusted for 1Khz in,500hz out but 2khz in about 1200 out etc.Is there a circuit to get over this?

[Meat-Head]

Caution advertisement

look at price first. Adjustable cures all evils work down to 3volt

https://www.ebay.co.uk/itm/HT-SH-V4-Speed-signal-modulator-unit-HealTech-Speedo-Healer-/202665179375

[gabrieleb]

It is a strange behaviour, you could also try with an Arduino or a small cheap microcontroller like PIC12F629, setting an interrupt and to the trick in the same way. Are you sure you are measuring the frequencies correctly?