A friend brought his Heathkit W7-M a while back for a look at D%, Etc. While we had the Spec'A hooked up I figured, why not a look at the PS sidebands on the signal. Refer to the attached.
I was surprised at the size of the 120 Hz, Etc sidebands on the One KHz test tone. The PS is a SS FWDoubler running into a pair of 150 microF Caps. No choke, but they have used a simple trick cct we resorted too at times, another 100 microF across the result.
The PT utilization is good in a FWD, so no problem there. But the other surprise was a rather large 60 Hz (power frequency), component greater than the 120 Hz. One would think symmetry would hold the 60 Hz down. Must be a problem with one cap in the doubler I think. But we had to cut it short, so don't know.
This all done using a PicoScope ADC-216 & Differential Probe set to x1000.
Information only.
I was surprised at the size of the 120 Hz, Etc sidebands on the One KHz test tone. The PS is a SS FWDoubler running into a pair of 150 microF Caps. No choke, but they have used a simple trick cct we resorted too at times, another 100 microF across the result.
The PT utilization is good in a FWD, so no problem there. But the other surprise was a rather large 60 Hz (power frequency), component greater than the 120 Hz. One would think symmetry would hold the 60 Hz down. Must be a problem with one cap in the doubler I think. But we had to cut it short, so don't know.
This all done using a PicoScope ADC-216 & Differential Probe set to x1000.
Information only.