--- David VanHorn <microbrix@gmail.com> wrote:

> So I tried varying the operating voltage.
> 12 batteries is what I've been using, the old lamps
> glow weakly, new
> ones flash nicely.
> 11 batteries, new lamps flash very slowly, old lamps
> glow weaker.
> 10 batteries, only one or two of the new lamps
> flash, old lamps are off.

To me it seems clear that the old bulbs are worn out,
albeit prematurely.

> I have never, EVER
> seen one of these
> circuits use a limiting resistor in series with the
> lamp. 

Until recently, all the circuits I have ever seen(and
built) have ALWAYS had limiting resistors. I think
this is the reason for the premature wear on the
bulbs.

Cheerful regards,

Bob

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