>
>
>On Mon, 21 Sep 1998 11:28:38 EDT TOMK5RC@aol.com writes:
>>
>>I have an Ameritron AL1200. The parasitc suppressor flashed a number of
times,
>>only on 20 meters, and finally burned up. I replaced the resistor with
>>two 120 ohm 2 watt carbon resistors in parallel. I also widened the diameter
>>of the coil. The parasitic has now moved up to 10 meters.
>>
>>Anyone with similar experiences?
>
>There have been several iterations of the AL-1200 stability problem Tom.
>Get the latest parts and info from Ameritron.
I hear that the "neutralization" mod decreases VHF stability.
>Also carefully inspect the bandswitch for arcs.
amen
>There is also a 1N4007 diode that is used to protect the B minus rail
>from rising. This diode will often short and cause high idling current
>which will add to stability problems. Replace with a 1N4008.. ...
1N5408? The 1N5400 series of diodes has a much higher peak current
rating than the the 1N4000 series.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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