Composite Black and White monitor dead

[tezza]

Just waiting on the replacement transistor Ian. Will check the PO Box tomorrow.

Tez

 

[tezza]

I checked but nothing there. Seems it's still on its way.

Tez

 

[harry]

"I checked but nothing there. Seems it's still on its way."

Damn post!! I,m on the edge of my seat here ..... doing great stuff Tez... .......harry

 

[tezza]

Transistor arrived.

Earlier today I screwed it in....connected everything up.....switched on....held my breath as I hear the odd crackle of components that hadn't had significant voltage through them for at least 25 years.

Then voila!

I left it going for about 25 mins. Seems fine. A slight hum from the power transformer and the faintest suggestion of a screen ripple if I stare hard enough at it but no more than most of my other monitors of this vintage.

I deem it fixed!

Many thanks to those who helped, especially Chuck who took the time to step me through the checks, and also sourced a replacement transistor. I owe you a beer or two if you ever make it to New Zealand Chuck.

All I need now are some TRS-80 badged stand-alone drives (actually just the badged drive cases..as I have full height drives), and I'll have an authentic disk-based TRS-80 Model 1 to show off.

Tez

 

[Chuck(G)]

Looks nice, Tez. Congratulations!

Oh, did you put some heatsink compound on that transistor flange before you bolted it down? It might help extend the life a bit more.

 

[tezza]

Oh, did you put some heatsink compound on that transistor flange before you bolted it down? It might help extend the life a bit more.

No, I didn't but thanks for the tip. Seeing the largest cost was postage, I got two transistors. Always good to have a spare.

Yes, I'm pleased. I got the screen for $1NZ and as you know the transistor wasn't much. So overall I now have a working TRS-80 M1 monitor without spending too much. They are ultra-rare here in NZ.

Tez

 

[MikeS]

Adding my congratulations for another job well done (and no doubt well documented ;-) )

Considering the voltages and stress on the HO transistor it is one of the most common parts to fail; you were lucky that it didn't take any other components with it when it did.

 

[angel_grig]

Congratulations Tez to you and Chuck who helped!

 

[tezza]

Adding my congratulations for another job well done (and no doubt well documented ;-) )

Considering the voltages and stress on the HO transistor it is one of the most common parts to fail; you were lucky that it didn't take any other components with it when it did.

Thanks Mike,

Yes, everything else seems to have survived. As usual there will be a blog post on the whole episode appearing soon...although a blow-by-blow account is pretty detailed in this forum so it will largely be a summary with some reflection. It will include a nice picture of my Model 1 setup anyway.

I just have to find the time to write it. As well as home life I'm involved in another big project at the moment (non-computer related). This cuts into time left for all other hobbies/interests and I feel I'm missing not connecting as much with the VC community.

Roll on retirement! (probably about 10 years to go on that score though).

Tez

 

[harry]

Great result for you Tez, you and chuck have made another interesting repair, I find these sort of things a great way to learn, and a little humor makes it good to follow!
well done..... Harry

 

[tezza]

Thanks Harry.

As usual I've written about the experience on my website.

Tez