I have OY from Mouser.
Someone said the interested value was out of stock. If you are going to
ship to Spain, then get the right type (OY) and just pick a higher value
where the parallel combo will give you the value you want. Easy solution
for the incremental cost over what would be a high shipping bill is
essentially zero.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message-----
From: Tom W8JI
Sent: Monday, December 28, 2015 4:13 PM
To: Jeff AC0C ; Jorge Diez CX6VM
Cc: 'topband'
Subject: Re: Topband: beverage resistors at Mouser.com
If you are going to make the order, consider using several in parallel to
improve the surge handling capability. I use 6x 2700 ohms here.
73/jeff/ac0c
Be real careful with the resistor choice.
A metal oxide or film resistor handles many times less surge than an OX or
OY resistor. OX and OY resistors are 14kV and 20 kV pulse rated respectively
without damage, and handle (OX) 40 and (OY) 70 watt-seconds for 100 pulses
of 1 second at 50% duty.
A standard metal oxide is not remotely close, and paralleling 10 will not
get them close. Even better MOX are only 10 watt-seconds, and not remotely
close to the peak pulse voltage (which will not increase when they are
parallel).
I've never actually had a single OY resistor used in a termination burn out
from lightning, despite some pretty hard hits. MOX are a different story
entirely.
Either type works fine so far as reactance goes, unless the application is
reactance critical. For a Beverage, reactance of either is not an issue.
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