My obscure interest: Vacuum Fluorescent Displays

[ChopperChas]

Hey, since you're the VFD master, maybe you can help me with my Pioneer CT-F850. My VFD is completely blank. It was working before the cassette deck was shipped to me, but is not working now. Here's the service manual: http://www.hifiengine.com/manual_lib.../ct-f850.shtml


I've taken some readings from the chips, board, and fluoroscan meter itself.

First off, there are two wires marked 3v AC on the board. Those measure at 1.3v AC between them. They are fed from the power supply board, and measure 1.3v there as well.

The display reads 1.3v AC between pins 1 and 33.
I'm also getting 15v DC (B+) at pins 3, 5, 18, and 32. (measured to the pin marked ground on the board that the display is soldered to)

On the chips, I'm getting 1.25v DC on pin 1, and 15v DC on pin 9. Everything except pin 18 is zero. Pin 18 is roughly 2.4v DC. (The voltage to this pin is adjusted via the VU meter level trimpots)

Any idea what's wrong with this thing? Something took a hit during shipping, but what could cause this?

Basically, if it's an easy fix, I'd like to keep the deck. If the VFD is toast, I'll return it.

Charles.