Have inherited an E-200C, the manual and schematic for which I happily obtained from this site. Seems to have a rather leaky power supply cap (the AC ripple looks atrocious when first turned on, but reduces after some time) and the output voltage looks a little weird.

1. What sort of ripple should be expected at the capacitors in this sort of circuit? I'm sure it's not as tight as today's designs, but what percentage is acceptable?

2. For this signal generator, what sort of magnitude should I expect at the RF output? Right now, the output is less than 2V maximum, and the waveform looks like a half-rectified sine wave. If it's supposed to be a full-sine, I'd guess a biasing problem on the RF tube.....?

thanks for any help getting used to the old stuff. It's great to work on something you can SEE.
Glen

Hi,

If you are going to be using the unit for serious amounts of work, save yourself some grief and just replace the filter caps. Generally you are going to have a rounded sawtooth (approx.), and some tubes are a little more tollerant of strong ripple than others. I would have to puruse a few theory books to find a tidy simple equation, but for the sake of long term reliability, it is easier to start out with fresh caps.

Your output should be a modulated sine wave. If you are getting only the half wave, check B+ first. You may have a resistor that is going/gone out of value to the point where one of the tubes is operating near cut-off. You may have a bad or shorted tube also.

2 Volts is usually more than adequate.

: Have inherited an E-200C, the manual and schematic for which I happily obtained from this site. Seems to have a rather leaky power supply cap (the AC ripple looks atrocious when first turned on, but reduces after some time) and the output voltage looks a little weird.

: 1. What sort of ripple should be expected at the capacitors in this sort of circuit? I'm sure it's not as tight as today's designs, but what percentage is acceptable?

: 2. For this signal generator, what sort of magnitude should I expect at the RF output? Right now, the output is less than 2V maximum, and the waveform looks like a half-rectified sine wave. If it's supposed to be a full-sine, I'd guess a biasing problem on the RF tube.....?

: thanks for any help getting used to the old stuff. It's great to work on something you can SEE.
: Glen