Tinman said: i am using a 10 watt 1 ohm resistor as my CVR,and only a 1 watt carbon resistor as the second resistor. FWIW Most power resistors of the consumer equipment type are wire wound and higher ohm types will have noticeable impedance at 3MHz, so are not reliable as a CSR at these frequencies. Add to that the fact that the cement block types absorb moisture which can act as a capacitance between the wire turns. Vitreous enamel types are not prone to moisture absorption, but may still have enough inductance to skew readings if used as a CSR at higher frequencies. Carbon film and metal film types may be spiral cut to final value, which adds a wee bit of inductance, carbon slug types would be better. Highly recommended is a quality CSR, which need not be expensive. I have fabricated my own at times from a chunk of carbon rod, although low inductance, it is not a high quality method. Also, I can wind low value low inductance, CSR's from Manganin wire, when needed, usually 0.1 ohm or less. I always use a Kelvin 4 wire measurement technique when grading my resistors in the lower ohm range.
---------------------------
"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
|
Author
Topic: Partnered Output Coils (Read 384976 times)
