KR-8050 Resistors

rbspop

rbs55pop
I shall take a chance and presume that Kenwood installed the resistors on the Preamp board in a vertical orientation to save space and/or shorten the signal path. At-any-rate: I have two questions. What is the coating they used on the exposed part of the legs? And what are the good/best resistors to use as replacements? BTW: I just placed the resistor in C25 to get a pic.

Resistor.JPG
 
Pic of a low noise resistor. The leeds act as antenna picking up stray fields.
To combat this, the resistor is mounted on one side/butt so no exposed leed.
The other leed is coated with "dunno" to shield the fields. You could use some
stripped wire insulation.

Plenty of choices, metal film preferred. Look for lower thermal drift. I'm
currently using Yageo MFR, 1% +/-50ppM/C. Vishay make some good resistors also.
 
Pic of a low noise resistor. The leeds act as antenna picking up stray fields.
To combat this, the resistor is mounted on one side/butt so no exposed leed.
The other leed is coated with "dunno" to shield the fields. You could use some
stripped wire insulation.

Plenty of choices, metal film preferred. Look for lower thermal drift. I'm
currently using Yageo MFR, 1% +/-50ppM/C. Vishay make some good resistors also.

Interesting ... Those are the resistors I just ordered. There are several bare wire jumpers on the board; however, I think that I will just use the "stripped wire insulation" method. Thanks
 
My guess is that it is done to conserve space. Other circuits might do that to provide additional cooling.

Principled engineering doctrine would indicate that 4" of copper foil on the board being terminated by a connection at a right angle constitutes a dipole antenna. If noise rejection was the goal, they selected a rather poor method of accomplishing that. And MBZ is correct - A metal foil or carbon would be more suitable than a wirewound, since a wirewound (even non-inductive) would tend to act as a loading coil for that miniature dipole antenna.
 
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