Sony Trinitron service menu reset.

[TetsuoXLI]

I was interested in seeing what resetting my TV to factory default settings would do. (Don't worry I wrote down all the values beforehand). I'm not sure why, but the convergence was messed up in parts of the screen and the image is tilted to a point where yolk adjustment would be needed. Why would this be? How could changing these values adjust things that seem so physical?

Any thoughts?

Thanks!

[ASDR]

It would potentially/likely brick your TV. The service menu contains all kinds of settings about the configuration of your particular model, everything from available inputs, tuner region, mono, stereo, presence of a rotation coil or other features like that, etc. etc. Real bad idea, won't help you.

[vol.2]

Why would this be? How could changing these values adjust things that seem so physical?

It's done electrically on newer, more expensive sets. The yoke is controlled by electromagnetism, and the service menu can change the values applied to the yoke components. There is still often magnetic strips applied to the tube for fine tuning.

Same with HSTAT and VSTAT, but those have been electrically controlled for a long time. I have Sony sets from the 70s with electrical HSTAT pots. It's trivial to automate these processes with modern ICs.

[TetsuoXLI]

I guess I got lucky. The normal menu has a rotation adjustment. The image looks better than it ever did before! I still don't understand how resetting could potentially brick my tv. Wouldn't these settings be the factory settings that were adjusted specifically for this set already? Surely they are intended to be ideal. Obviously since it's all analogue, I'm sure things change over time. Is there any way to learn the knowledge of a CRT technician nowadays? I've been watching Randy Fromm's CRT workshop on YouTube, but so much remains a mystery.
'

[vol.2]

I still don't understand how resetting could potentially brick my tv.'

I don't think it will, but you'd have to be very sure what kind of a reset you're doing. Are you using a TV or a PC monitor? I don't think I've seen yoke adjustment in the user menu on a consumer TV before, but my Sony PC monitors do have that.

Pretty sure it's not an option on my Sony HDCRT in the regular menu.

[Bassa-Bassa]

Do you mean this adjustment?



That's definitely a thing on some TV sets as well. That pic's from the A2-F2 chassis service manual, for instance.

[vol.2]

Do you mean this adjustment?

That's what I meant. I'm not sure I recall seeing it on a consumer TV before, though I may be forgetting.

[matt]

I guess I got lucky. The normal menu has a rotation adjustment. The image looks better than it ever did before! I still don't understand how resetting could potentially brick my tv. Wouldn't these settings be the factory settings that were adjusted specifically for this set already? Surely they are intended to be ideal. Obviously since it's all analogue, I'm sure things change over time. Is there any way to learn the knowledge of a CRT technician nowadays? I've been watching Randy Fromm's CRT workshop on YouTube, but so much remains a mystery.
'

No. The factory settings will put it into a state before it was set up at the factory. That includes stuff like what AV inputs are enabled, what features work or not, and all the geometry & color balance settings. Sony used the same hardware for multiple TVs and if you reset it, the TV won't know what model it's supposed to be any more. Also, tube electronics are naturally variable and every TV is set up differently.

The best you can do is to look up the default setting in the service manual and work from there. That's a better starting point than a total reset.

[matt]

That's what I meant. I'm not sure I recall seeing it on a consumer TV before, though I may be forgetting.

All of Sony's flat tube consumer CRTs have a rotation coil. It's not a common feature with other brands, though.

[vol.2]

All of Sony's flat tube consumer CRTs have a rotation coil. It's not a common feature with other brands, though.

What I said was that I don't remember seeing it in the user settings, only in the service menu.

[ASDR]

No. The factory settings will put it into a state before it was set up at the factory. That includes stuff like what AV inputs are enabled, what features work or not, and all the geometry & color balance settings. Sony used the same hardware for multiple TVs and if you reset it, the TV won't know what model it's supposed to be any more. Also, tube electronics are naturally variable and every TV is set up differently.

Yes, this. Resetting all settings has a good chance of your TV not turning on or at least not displaying anything. Even taking pictures of all the settings won't help you. You'd basically have to get an NVRAM dump from the same model to recover from this. Terrible idea, never do this.

All of Sony's flat tube consumer CRTs have a rotation coil. It's not a common feature with other brands, though.

Omitted on <21" models, though.

[matt]

All of Sony's flat tube consumer CRTs have a rotation coil. It's not a common feature with other brands, though.

Omitted on <21" models, though.

The US 13" and 20" models do have a rotation coil, except in their very last year of production. I'm sure it was omitted in some regions.