Believe an oscillator isn't operating. When you switch on the crystal calibrator it's makes up for an oscillator which isn't operating.
Norm
:I Recently bought a Hallicrafters SX-100 Mark 2 on eBay. I’ve replaced all electrolytics and the paper caps except the ones in the 2nd osc/mixer sub chassis. I replaced the RF amp, 1st osc & 1st mixer tubes. With my signal generator connected to the antenna terminal & set to appropriate freq., I get signal on all 3 shortwave bands but nothing on broadcast. With an antenna hooked up, I get nothing on BC. I get a few stations on the SW bands but weirdly, only when it’s set to CW-SSB and with the xtal calibrator on. Anybody have any ideas what could be wrong? Thanks, Mark