Just a thought, but a couple of dollars (less than $20 IIRC) buys a battery
operated doorbell that uses a couple of alkaline C-cells that last for many
years. Makes it very easy to add a second bell in a basement shop or garage
that also rings, if needed.
Been decades since I had a doorbell trans
--- On Sat, 10/23/10, Phil Kane wrote:
> If you mean the doorbell transformer, the insulation dries out
> and turns start shorting, leading to excessive heating and
> internal arcing. They usually have an internal thermostat to
> cut it off when hot, and after it cools down it starts all
On 10/22/2010 7:49 PM, Jim Miller wrote:
> What is there about a transformer that causes so much grief? Curious...
If you mean the doorbell transformer, the insulation dries out
and turns start shorting, leading to excessive heating and
internal arcing. They usually have an internal thermo
They are cheaply built with little insulation. A good power
surge or lightning strike will puncture the insulation and
the primary will arc to the frame/core on peaks of the wave.
Door bell transformer failure will have a marked 120 Hz rough
note. The homeowner should consider themselves lucky
What is there about a transformer that causes so much grief? Curious...
73
jim ab3cv
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On 10/22/2010 4:08 PM, Dick Williams wrote:
> After a little "detective work", I traced the source of the
> interference to the doorbell transformer. Disconnected it, and
> told him to go buy a new one.
When I was doing residential RFI-hunting in the 1970s-1990s,
doorbell transformers were t
Quite a coincidence.
In 1978 I had horrible RFI that blanketed HF and 2 meters and also
affected TVs and even people's stereo systems. Naturally, my neighbor
asked if it could be my ham radio. At one point I looked out and saw
another guy walking up and down the street with a portable radio, t
told him to go buy a new
one. Of course we were both "happy campers".
Dick K8ZTT
-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Lou Kolb
Sent: Friday, October 22, 2010 4:24 PM
To: elecraft
Subject: Re: [Elecraf
ed generating a
terrible hash. When I pulled it the problem was immediately solved. 73,
Lou WA3MIX
- Original Message -
From: "Ron D'Eau Claire"
To: "'Mike Weir'" ;
Sent: Friday, October 22, 2010 5:10 PM
Subject: Re: [Elecraft] QRM and filtering
&
That sounds like arcing somewhere Mike (BTW, it's QRN - N - noise instead of
QRM -M for interference from other stations).
It could be a power line insulator. Sometimes a fluorescent bulb dying
sounds like that as the starter keeps re-engaging. I've heard that sort of
thing from some street light
Over the last 2 weeks some QRM has shown up and I have tried some of the NR and
NB filtering options to get rid of it and it's not really working to well. I am
not sure if I am using the proper filtering or the settings I am using are off.
I have an audio example of the QRM or even RFI on my bl
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