Frequency counter. - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Various and Sundry Categories (https://philcoradio.com/phorum/forumdisplay.php?fid=37)
+--- Forum: Test Equipment (https://philcoradio.com/phorum/forumdisplay.php?fid=31)
+--- Thread: Frequency counter. (/showthread.php?tid=9964)

---

Frequency counter. - fields 100 - 07-07-2014

On my Heath Zenith SM 2420 counter there is a "Trigger" knob. When I switch bands on my signal generator, it has to be reajdusted every time to display correct frequency.I do not trust completely my sig. gen., however it is within 100HZ accuracy. As an example, after aligning IF at 260 K.C. I switched to the different band for 1400 K.C. and set the dial on the generator accordingly. The meter displayed 1800.After playing with a "Trigger " knob the screen on the meter indicated 1400. Is that normal? I do not recall such issues in the past. Thanks.

---

RE: Frequency counter. - Mondial - 07-07-2014

The situation you describe is pretty normal. The waveshape of the output signal changes on each band, so the trigger level may have to be adjusted to compensate for the difference in the waveform symmetry.

The triggering is more critical when the output signal is low. Try to increase the generator output when you have the counter connected to set the freq, then reduce it to the required level for alignment.

The best way to minimize the problem is to add an extra output to the generator, connected before its internal atrtenuator. That way you can continuously monitor the freq while simultaneously generating the attenuated lower lever signal for alignment.

---