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Skipper 300

Tweetybird

Well-Known Member
Jun 23, 2019
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I have a skipper that squeals when key watts normal at first then climbs to 900 watts putting 4 watts in about 10 seconds after keying squeals right away any ideas
 

Bad parasitic filters
I ordered a tube conversion schematic I hope it's on there I dont know what a parasitic filter looks like is it on the output part by the tubes? I'm new to this had electronics in high school 45 years ago thank you for responding
 
The parasitic chokes/filters are resistors with wires wound around them. Look at some pictures of old tube amps they are in line with the B+ line going to the tube.
 
The one I think is bad is the one before the driver tube on inlet it has a crack it's not the wire wound one in the center of the three power ones itsthe one on back nob
 
The parasitic chokes/filters are resistors with wires wound around them. Look at some pictures of old tube amps they are in line with the B+ line going to the tube.
I bought two watt 47 ohm axial resistors is the red band end the plus end?
 
The parasitic chokes/filters are resistors with wires wound around them. Look at some pictures of old tube amps they are in line with the B+ line going to the tube.
The wires coils dont just bypass the resistor? There is an old linear on ebay with like 8 tubes it had pictures! I am trying to grasp the coil bypass does the resistor absorb the oscillations as they pass by it?
 
The wires coils dont just bypass the resistor? There is an old linear on ebay with like 8 tubes it had pictures! I am trying to grasp the coil bypass does the resistor absorb the oscillations as they pass by it?
The resistor and the coil "Swamp" out some of the parasitic oscillations and keeps the B+ clean for the other tubes. Do not underestimate a few turns of wire in RF Circuits.
Read the article that Shadetree Mechanic and some of the mystery's will be answered, Or even more questions formulated.
 
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The resistor and the coil "Swamp" out some of the parasitic oscillations and keeps the B+ clean for the other tubes. Do not underestimate a few turns of wire in RF Circuits.
Read the article that Shadetree Mechanic and some of the mystery's will be answered, Or even more questions formulated.
Ok I made six one for each tube I will read shadetreesarticle thank you again
 

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