There's a quad in the not-too-distance future here - might be a few
months because of the remodelling going on right now, but looking for
parts. Need quad spreaders and a remote switch. Have Cubex spiders and
a set homebuilt from long ago that are aluminum but that hold the
poles at an angle like the Gem quad.
Anyone have poles or a source of good poles (beside Cubex)? Ever use
Calcutta poles? Antenna switch lying around?
Michael Goins, k5wmg
Professor, Writing
University of Texas at San Antonio
Please do not print this e-mail unless it is completely necessary
On Wed, Jan 28, 2009 at 4:55 PM, Jim Lux <jimlux@earthlink.net> wrote:
>
>
> -----Original Message-----
>>From: Kipton Moravec <kip@kdream.com>
>>Sent: Jan 28, 2009 2:29 PM
>>
>>I can answer the diode question.
>>
>>It is generally good practice to put a diode across the relay because of
>>the inductive spike when turning it off. I have seen the spike go 3-4X
>>the input voltage. If you may have a very long line to the relay the
>>spike may be more.
>>
>
> Actually, the relay manufacturers (e.g. Tyco, P&B, etc.) recommend NOT using
> the diode across the coil, because it reduces relay life and changes
> actuation speed. Depending on whether you're suppressing across the coil or
> load, the approaches are different.
>
> http://relays.tycoelectronics.com/appnotes/app_pdfs/13c3311.pdf
>
> as they say:
> "Many engineers use a rectifier diode alone to provide the transient
> suppression for relay coils. While this is cost effective and fully
> eliminates the transient voltage, its impact on relay performance can be
> devastating."
>
> Jim, W6RMK
>
>
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