Those ancient carbon resistors go well out of tolerance from age and RF.
Try your MOX as not all brands are created equal. If they smoke then get the
modern Ohmite OY series stocked at Mouser and others.
The easiest solution for WARC smoking the plate choke is to unwind 3-4 turns
from the top but it does nothing to preserve parasitic suppressors.
Carl
----- Original Message -----
From: "K2CB" <k2cb@comcast.net>
To: <Amps@contesting.com>
Sent: Sunday, March 08, 2015 12:24 PM
Subject: [Amps] Clipperton L parasitic suppressor a
I am working on a Clipperton L. It seems to work fine on all bands.
However, on 10m the parasitic suppressor resistors seem to be overheating.
One or two of the four resistors looked like they've been overheated
before, thus I was not surprised when I tested it myself on 10m and began
to smell the familiar odor of burning resistors.
The manual calls for 100 ohm 2 watt resistors. Can I use metal oxide
flame proof resistors, or do they need to be carbon composition resistors?
For some reason I seem to recall reading that the mox resistors cause
issues, but I could be wrong.
I have a bunch of mox 100 ohm 2w resistors in my parts bins, but no carbon
resistors. Can you still get larger size carbon comp resistors?
If so, does anyone have a recommended Mouser or DigiKey part number, or
series type, suitable for suppressor usage?
Also, in regards to the 10m heating issue, would it be worth it to go to a
5w resistor, or double up and use two 200 ohm 2w resistors in parallel?
Thanks,
Eric
K2CB
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