UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Pin-out for SEI Quartz Oscillator

Brian of Romsey · 12th Jul 2018, 10:20 pm

Hi,

I finally got round to testing and sorting this oscillator. It does work (which is always a worry for second hand stuff from a radio rally).

At 9.0 Volts it draws between 3 mA and 8 mA on the pin diagonally opposite the ground pin. The output is a sinewave, centred on ground, with an amplitude of 2.9 Volts peak-to-peak when loaded only with the 'scope and 1.8 Volts peak-to-peak when loaded with 50 Ohms.

The pin-out, viewed from above (like normal chips are):

+------------------------+
| 4 = Ground ... Out = 3 |
| 1 = N/C .. 9 Volts = 2 |
+------------------------+

Strangely my bench PSU seemed unable to deliver a solid supply, loads of ripple - 840 mVolts! Even with a 47 nF polyester & a 470 pF polystyrene right across the pins the ripple only got down to 530 mVolts. Ah well, the output looked like a clean sinewave no matter what.

Cheers, Brian.

12th Jul 2018, 10:20 pm	#8
Brian of Romsey Triode Join Date: Jul 2017 Location: Fairfield, Melbourne, Australia Posts: 48	Re: Pin-out for SEI Quartz Oscillator Hi, I finally got round to testing and sorting this oscillator. It does work (which is always a worry for second hand stuff from a radio rally). At 9.0 Volts it draws between 3 mA and 8 mA on the pin diagonally opposite the ground pin. The output is a sinewave, centred on ground, with an amplitude of 2.9 Volts peak-to-peak when loaded only with the 'scope and 1.8 Volts peak-to-peak when loaded with 50 Ohms. The pin-out, viewed from above (like normal chips are): +------------------------+ \| 4 = Ground ... Out = 3 \| \| 1 = N/C .. 9 Volts = 2 \| +------------------------+ Strangely my bench PSU seemed unable to deliver a solid supply, loads of ripple - 840 mVolts! Even with a 47 nF polyester & a 470 pF polystyrene right across the pins the ripple only got down to 530 mVolts. Ah well, the output looked like a clean sinewave no matter what. Cheers, Brian.