16 August 2007

Cheap eBay XTALs

In April 2006 I bought a batch of XTALs via eBay from a Chinese shop. The shop is still open (16 August 2007) but currently does not list XTALs.

I took 2x7030, 4x14060 and 4x14020 kHz: 10 XTALs for 18 US$ shipped. Good deal! Not so...

I recently planned to use those XTALs for my homebrew 4m TX , which started to come to life on August 14th, 2007.

On a Colpitts test oscillator, the 14060k XTALs was resonating on 14020k. OPS! The 14020k was close to 14060kHz. I tested a couple more crystals and the mis-marking was confirmed. The 7030k rock went on at 7028kHz, which is reasonably close to the marked frequency, and perhaps my oscillator was pulling it a bit.

Lesson learned? Be careful with cheap components on eBay!