Emerson Clock Radios

[old_coot88]

Originally Posted by old_tv_nut

Later electronic clocks followed the 60 cycle power (many still do), but were (are) subject to counting occasional transient spikes as additional cycles, and therfore run fast.

He's had two Emerson units show the same problem (running slow). Assuming they're synced to the powerline*, and it's 'dirty' with transients, would the spikes necessarily show as additive (positive-going), or could they induce negative-going dropouts? I dunno, just wonderin'.

* EDIT. That's assuming both units to be digital.

[old_tv_nut]

Originally Posted by old_coot88

He's had two Emerson units show the same problem (running slow). Assuming they're synced to the powerline*, and it's 'dirty' with transients, would the spikes necessarily show as additive (positive-going), or could they induce negative-going dropouts? I dunno, just wonderin'.

* EDIT. That's assuming both units to be digital.

I suppose it's possible for a circuit to be filtered heavily to avoid spikes and then miss a cycle if there is an occasional reduced amplitude one. I can only say I haven't seen slow running, only fast, on the cheap units I have owned.

In either case it seems to be a basic failing of something that counts pulses rather than something with inertia (a motor) that coasts through transients.