AMRAD LF Active Antenna Question

[Andre Kesteloot]

Hello Mark,

yes indeed, as Rob wrote, the part you need is a Neon bulb type NE-2.
You will find it at Digi-Key for 54 cents.
Digi Key does not have a minimum order and will mail small items First Mail
in a small envelope.

*http://www.digikey.com/product-detail/en/A1A/A1A-ND/4176016
<http://www.digikey.com/product-detail/en/A1A/A1A-ND/4176016>*

​This neon bulb looks like a high impedance (open circuit) until you apply
between 70 and 90v across it, as which time, the neon gas in the envelope
starts conducting. It then presents an extremely low resistance
(essentially a short-circuit) between the two electrodes.

As it is connected, if a high static voltage (thunderstorms, ...) were to
appear at the antenna, the bulb would strike and the static voltage would
be shorted to ground. Upon disappearance of that high volagte spike, the
neon tube would stop conducting, and the signal fro the antenna would again
be amplified by the received.



On Sun, Nov 2, 2014 at 4:53 PM, Robert Seastrom <rs at seastrom.com> wrote:

>
> On Nov 2, 2014, at 4:37 PM, Mark Fancher <mark.fancher at twc.com> wrote:
>
> > Looks like the LED specified for the antenna (not the power supply)
> isn’t offered by Radioshack anymore.  Will this thing work without that LED
> or is it required?
>
> Hi Mark,
>
> I just looked at the schematic and I don't see an LED in the antenna
> amplifier schematic.
>
> Attention to
> http://www.arrl.org/files/file/Technology/tis/info/pdf/0109031.pdf
>
> Are you perchance referring to "DS1NE-2 neon lamp (272-1102)" in the
> schematic on page 34?
>
> If so, that's actually a neon indicator bulb and at a guess it's there to
> provide a static discharge path so that the first thunderstorm within 10
> miles doesn't send Q1 to the great parts bin in the sky.
>
> There seem to be NOS NE-2 neon bulbs on eBay.  Guess those are one of
> those things that used to be super common and are now hard to find.
>
> The original authors are around and subscribed to the list; perhaps they
> will chime in.
>
> 73,
>
> de AI4UC
>
>
>
> _______________________________________________
> Tacos mailing list
> Tacos at amrad.org
> https://amrad.org/mailman/listinfo/tacos
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://amrad.org/pipermail/tacos/attachments/20141102/b404ceb9/attachment.html>