Canadian Marconi TV 102T17

[irext]

With resistors in older gear I tend to go double the wattage since a 1/2 watt resistor nowadays is about half the physical size of the original 1/2 watt. Metal film resistors seem fine. I know some have concerns about breakdown with high voltages but I've not had any failures (yet).

[maxhifi]

Originally Posted by irext

With resistors in older gear I tend to go double the wattage since a 1/2 watt resistor nowadays is about half the physical size of the original 1/2 watt. Metal film resistors seem fine. I know some have concerns about breakdown with high voltages but I've not had any failures (yet).

I'm changing them out one by one with metal films. I never realized how tedious it is to change resistors and maintain original lead dress... There's just so many of them! Very few are within tolerance, the good ones are 10% off, but some are double in value and even worse.

[Penthode]

By saying the resistors are far off, how far off are they? The resistor values are generally not too critical except for some circuits. You may find changing all the resistors a wasted effort if it doesn't make any noticeable difference.

Note most are likely +/-20%. Even outside that it often Doesn't matter. It would be better to focus on the capacitors and only attack the resistors if there is a specific problem.

[maxhifi]

Originally Posted by Penthode

By saying the resistors are far off, how far off are they? The resistor values are generally not too critical except for some circuits. You may find changing all the resistors a wasted effort if it doesn't make any noticeable difference.

Note most are likely +/-20%. Even outside that it often Doesn't matter. It would be better to focus on the capacitors and only attack the resistors if there is a specific problem.

Most are between 20%-100% off. On average 30-50% high, with cathode resistors reading up to 250% of marked value. This specific TV has the most off resistors I've ever encountered in on TV during a restoration, so I decided to change them all, usually I only replace parts which cause a specific malfunction, as you say.