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The TRS-80 Model III experience - Getting this working???

Frank S

Experienced Member
Joined
Mar 31, 2013
Messages
271
Location
Germany
Today i get my TRS-80 Model III shipped from the US via the international trading program from eBay.
No good noises comes out of the closed box, when i give it a little shake.
After opening the box and remove the few "cushion elements", the complete harm is to see.
What does the seller think, when he packed the box with the Model III?
Frank
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I carry all the parts to get this computer going. Shipping a CRT is going to be costly. Although your power supply is damaged, you will probably want to convert to a 240V one anyway.

The question is, of the 4 posts which retain the CRT to the black bezel, how many are ok? I have managed to JB Weld 3 out of 4 and got a CRT to mount successfully... 4 out of 4 I would be worried.

Ian.
 
For the benefit of ALL of us...

please

submit a report/complaint to Ebay, IMMEDIATELY!!!

This is tantamount to fraud, IMO. :(

... and good luck!
 
If by "international trading program" he means the eBay Global Shipping Program, good luck! When items are shipped via the GSP, Pitney Bowes (who eBay contracted to run it) reserves the right to open, inspect, and repackage items at their shipping center in Kentucky. If that is what happened, the seller would say "that's not my packaging!" and then the fight to get the refund would be between the buyer and Pitney Bowes.

Here's an explanation of how it works, and the potential problems:
http://www.youtube.com/watch?v=HLLrqz1Esj4#t=5m50s
 
...The question is, of the 4 posts which retain the CRT to the black bezel, how many are ok? I have managed to JB Weld 3 out of 4 and got a CRT to mount successfully... 4 out of 4 I would be worried. Ian.
Hello Ian,
all posts are damaged. But i am sure, that i get it fixed. A new tube i order in the near of me.
Also the cage for the mainboard is slighly bended. A 230V power supply i have already, so is no need for the damaged 115V power supply.
I report, when the picture tube is here and mounted.

Frank
 
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Sorry to hear about your machine Frank.

Having just changed the tube in my TRS-80 model 4 I have a bit of info which might help you. I believe the tube used in the model 3 is a 12VCMP4. I believe however you can install a 12VCMP31 as used in the model 4 if you replace the electrolytic capacitors on the video board to bring the signals back into spec. The 12VCMP31 monitor is fully interchangeable with various tubes around including the Orion 310GNB31 which is used in the GT-65 monochrome monitor for the Amstrad CPC6128 (which I think was badged as a Schneider in Germany). This info was sourced from a really good PDF I found on the net called "TRS8BIT".

I hope this info helps.
 
Hello Chris,
The CRT tube i ordered for 16€ is a M28-12W.
So, i think it is a 12" size. Yesterday i get it. No...., it measures 28cm in diagonal.
I am looking forward for a new CRT tube.
Frank
 
Ugh! I hate to see an old classic treated with such disrespect. I hope you bring her back to life Frank! Good luck!
 
The next few steps.
Three of the posts for CRT tube are broken directly at the end of the threat of the studs.
So only about 6mm broke away. One post is broken near the monitor frame.
I glue it with epoxy and fabric. Then i cut all posts even and to the same length.
The studs are long enough to hold the new CRT tube.
I also make the mainboard cage even and give it a new power supply (100-240V)
and a power distributor like the old one on the power supply.
I removed the fixed power cord and add a IEC C14 plug into the bracket.
Up to now, i doesn't know, if the TRS-80 Model 3 mainboard works, but i am hopeful.
Frank
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Success....
Today i get a Amstrad GT65 monitor from the UK.
The CRT tube is the ORION 310GNB31, which is also a tube with 90° deflection.
It fits very well in the TRS-80 Model III case.
The original tube socket from the TRS-80 is totally destroyed, so i use the GT65 one.
I cut the PCB around the socket to an round shape, drill some holes for the neon lamp and the resistors.
I power it up and it works at once. Only two key switches does not work (space and letter "G").
After opening and cleaning the contacts also they works fine.
Loading some cassette games, all works fine.
Frank
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That is excellent news Frank! Having just imported a model 4 from the US to Europe I think you went through my worst nightmare. I was lucky, and I guess you weren't however you have done a great job of this and I'm really pleased for you that it is now working!

Well done!
 
Thanks Chris,
i also buy an ATARI SM124 monitor, which uses the Goldstar 310KAB4k tube.
But the GT65 arrived earlier. I take a look of the SM124 tube, if it also works.
Then we have some compatible tubes for TRS-80's sending from the US.:cool:
Frank
 
No matter what I have personally tried (and those who dealt with me on ebay know this), the Model III and IV are extremely hard to ship. You literally have to remove the CRT and package it separate or else rough handling will cause the mounts to break and...well yeah.
 
No matter what I have personally tried (and those who dealt with me on ebay know this), the Model III and IV are extremely hard to ship. You literally have to remove the CRT and package it separate or else rough handling will cause the mounts to break and...well yeah.

That's kind of what I was thinking. The packing job is bad, yes, but it must have had a pretty good rough handling and no amount of packing outside of the computer case would have prevented that. You'd have to remove the tube as you said or brace it internally before shipping I would think. I know mine looked pretty flimsy inside.
 
It's something in particular with those models and their supports crumbling. My Model II was shipped in similar conditions (mind you I didn't care because it WAS pulled out of a ditch) but the tube was fine.
 
No matter what I have personally tried (and those who dealt with me on ebay know this), the Model III and IV are extremely hard to ship. You literally have to remove the CRT and package it separate or else rough handling will cause the mounts to break and...well yeah.
I agree with that. When the parcel carrier drops the TRS-80 on the back, the tube must get lose.
The threats of the mounting studs that goes into the plastic posts are very short to withstand the force of the CRT tube, when dropping.
I add two pictures from the socket.
Frank
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